#1153 Drawings that are pure annotation now do not generate references

#1153 New markers and patterns for insulation batting, steel, and wood grain
#1153 Predefined type is now also included in CSS classes for drawings.
2026-08-09 09:21:46 +00:00 · 2022-04-17 12:29:34 +10:00 · 2022-04-17 12:19:20 +10:00 · 2022-04-16 18:32:17 +10:00 · 2022-04-15 19:45:59 +10:00 · 2022-04-15 11:45:23 +10:00
957 changed files with 50922 additions and 12509 deletions
@@ -28,7 +28,7 @@ jobs:
        sudo apt update
        sudo apt-get install --no-install-recommends \
        git cmake gcc g++ libboost-all-dev python3-all-dev swig libpcre3-dev libxml2-dev \
-        liboce-foundation-dev liboce-modeling-dev liboce-ocaf-dev liboce-visualization-dev liboce-ocaf-lite-dev \
+        libocct-foundation-dev libocct-modeling-algorithms-dev libocct-modeling-data-dev libocct-ocaf-dev libocct-visualization-dev libocct-data-exchange-dev \
        libhdf5-dev libcgal-dev

    -
@@ -47,7 +47,7 @@ jobs:
         -DCMAKE_PREFIX_PATH=/usr \
         -DCMAKE_SYSTEM_PREFIX_PATH=/usr \
         -DBUILD_PACKAGE=On \
-         -DOCC_INCLUDE_DIR=/usr/include/oce \
+         -DOCC_INCLUDE_DIR=/usr/include/opencascade \
         -DOCC_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu \
         -DPYTHON_EXECUTABLE:FILEPATH=/usr/bin/python3 \
         -DPYTHON_INCLUDE_DIR:PATH=/usr/include/python3.8 \
@@ -23,12 +23,13 @@ jobs:
      run: echo ok go

  build:
+    needs: activate
    name: ${{ matrix.config.name }}-${{ matrix.pyver }}
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
-        pyver: [py37, py39]
+        pyver: [py37, py39, py310]
        config:
          - {
            name: "Windows Build",
@@ -41,7 +41,7 @@ jobs:
          python3-all-dev python3-pip \
          swig libpcre3-dev libxml2-dev \
          libtbb-dev nlohmann-json3-dev \
-          liboce-foundation-dev liboce-modeling-dev liboce-ocaf-dev liboce-visualization-dev liboce-ocaf-lite-dev \
+          libocct-foundation-dev libocct-modeling-algorithms-dev libocct-modeling-data-dev libocct-ocaf-dev libocct-visualization-dev libocct-data-exchange-dev \
          libhdf5-dev libcgal-dev
          
      - name: ccache
@@ -53,11 +53,10 @@ jobs:
          cmake \
               -DCMAKE_C_COMPILER_LAUNCHER=ccache \
               -DCMAKE_CXX_COMPILER_LAUNCHER=ccache \
-               -DCMAKE_INSTALL_PREFIX=$PWD/install/ \
               -DCMAKE_BUILD_TYPE=Release \
               -DCMAKE_PREFIX_PATH=/usr \
               -DCMAKE_SYSTEM_PREFIX_PATH=/usr \
-               -DOCC_INCLUDE_DIR=/usr/include/oce \
+               -DOCC_INCLUDE_DIR=/usr/include/opencascade \
               -DOCC_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu \
               -DPYTHON_EXECUTABLE:FILEPATH=/usr/bin/python3 \
               -DPYTHON_INCLUDE_DIR:PATH=/usr/include/python3.8 \
@@ -83,6 +82,8 @@ jobs:
          sudo /usr/bin/python -m pip install src/bcf
          sudo /usr/bin/python -m pip install pytest
          sudo /usr/bin/python -m pip install isodate
+          sudo /usr/bin/python -m pip install lark
+          sudo /usr/bin/python -m pip install networkx

      - name: Test
        run: |
@@ -18,14 +18,14 @@ jobs:
      - name: Checkout
        uses: actions/checkout@v2
        with:
-          lfs: true
+          submodules: recursive
      - 
        name: Update ubuntu
        run: |
          sudo apt update
          sudo apt-get install git cmake gcc g++ libboost1.67-all-dev python3-all-dev swig libpcre3-dev libxml2-dev
-          sudo apt-get install liboce-foundation-dev liboce-modeling-dev liboce-ocaf-dev liboce-visualization-dev liboce-ocaf-lite-dev \
-          libhdf5-dev
+          sudo apt-get install libocct-foundation-dev libocct-modeling-algorithms-dev libocct-modeling-data-dev libocct-ocaf-dev libocct-visualization-dev libocct-data-exchange-dev \
+          libhdf5-dev libcgal-dev
          
      - name: Build
        env:
@@ -39,7 +39,7 @@ jobs:
           -DCMAKE_PREFIX_PATH=/usr \
           -DCMAKE_SYSTEM_PREFIX_PATH=/usr \
           -DBUILD_PACKAGE=On \
-           -DOCC_INCLUDE_DIR=/usr/include/oce \
+           -DOCC_INCLUDE_DIR=/usr/include/opencascade \
           -DOCC_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu \
           -DPYTHON_EXECUTABLE:FILEPATH=/usr/bin/python3 \
           -DPYTHON_INCLUDE_DIR:PATH=/usr/include/python3.8 \
@@ -8,3 +8,9 @@
 [submodule "src/svgfill"]
 	path = src/svgfill
 	url = https://github.com/IfcOpenShell/svgfill
+[submodule "src/ifcopenshell-python/ifcopenshell/Sample-BIM-Files"]
+	path = src/ifcopenshell-python/ifcopenshell/Sample-BIM-Files
+	url = https://github.com/atomczak/Sample-BIM-Files
+[submodule "src/ifcopenshell-python/test/Sample-BIM-Files"]
+	path = src/ifcopenshell-python/test/Sample-BIM-Files
+	url = https://github.com/atomczak/Sample-BIM-Files
@@ -1,7 +1,9 @@
 IfcOpenShell 
 ============
 IfcOpenShell is an open source ([LGPL]) software library for working with the Industry Foundation Classes ([IFC]) 
-file format. Currently supported IFC releases are [IFC2x3 TC1] and [IFC4 Add2 TC1].
+file format. Extensive geometric support is implemented for the IFC releases [IFC2x3 TC1] and [IFC4 Add2 TC1].
+Support for parsing is provided for IFC4x1, IFC4x2, and the IFC4x3 release candidates. Extending with support for
+arbitrary IFC schemas is possible at compile-time when using C++ and at run-time when using Python.

 For more information, see
 * [http://ifcopenshell.org](http://ifcopenshell.org)  
@@ -13,7 +15,7 @@ Prerequisites
 -------------
 * Git
 * CMake (2.6 or newer)
-* Windows: [Visual Studio] 2008 or newer with C++ toolset (or [Visual C++ Build Tools]) or [MSYS2] + MinGW
+* Windows: [Visual Studio] 2008 to 2019 (2022 not yet supported by dependency CMake) with C++ toolset (or [Visual C++ Build Tools]) or [MSYS2] + MinGW
 * *nix: GCC 4.7 or newer, or Clang (any version)

 Dependencies
@@ -33,7 +35,11 @@ Dependencies
 Building IfcOpenShell
 ---------------------

-**Note:** The path where the source code is cloned to can contain spaces but non-ASCII characters are very likely to cause problems with the build.
+Note 1: The path where the source code is cloned to can contain spaces but non-ASCII characters are very likely to cause problems with the build.
+
+Note 2: If you had not used `git clone --recursive https://github.com/IfcOpenShell/IfcOpenshell.git`, update the submodules by running `git submodule init & git submodule update`.
+
+Note 3: Be careful with special characters is the path when using the nix or win build scripts, because the OpenCASCADE build will fail on paths containing ++ and likely other situations.

 ### Compiling on Windows
 The preferred way to fetch and build this project's dependencies is to use the build scripts
@@ -81,17 +87,26 @@ The following instructions are for Ubuntu, modify as required for other operatin
 can be experimented with and studied for pointers for other operating systems, but note that this script is not currently
 meant to be used for a typical IfcOpenShell workspace setup.

-Note: where `make -j` is written, add a number roughly equal to the amount of CPU cores + 1.
+Note 1: It is recommeded to use OCCT for IfcOpenShell. You could use OCE as well, but sometimes it may lag behind OCCT and 
+therefore not compile with the latest IfcOpenShell.
+
+Note 2: where `make -j` is written, add a number roughly equal to the amount of CPU cores + 1.

 **1)** Install most of the prerequisites and dependencies:

-    $ sudo apt-get install git cmake gcc g++ libboost-all-dev
+    $ sudo apt-get install git cmake gcc g++ libboost-all-dev libcgal-dev

-**2a)** Either use an OCE package from your operating system's software repository
+**2a)** Either use an OCCT package from your operating system's software repository
+
+    $ sudo apt-get install libocct-data-exchange-dev libocct-draw-dev libocct-foundation-dev libocct-modeling-algorithms-dev libocct-modeling-data-dev libocct-ocaf-dev libocct-visualization-dev
+
+**2b)** or, if OCCT is not available or the latest code is wanted, obtain and compile OCCT from https://dev.opencascade.org/release
+
+**2c)** or, if you'd like to try using OCE, use the package from your operating system's software repository

    $ sudo apt-get install liboce-foundation-dev liboce-modeling-dev liboce-ocaf-dev liboce-visualization-dev liboce-ocaf-lite-dev

-**2b)** or (if not available, or the latest code is wanted) compile OCE yourself (note that the build takes a long time):
+**2d)** or if OCE is not available, or the latest code is wanted, compile OCE yourself (note that the build takes a long time)

    $ sudo apt-get install libftgl-dev libtbb2 libtbb-dev libgl1-mesa-dev libfreetype6-dev
    $ git clone https://github.com/tpaviot/oce.git
@@ -101,8 +116,6 @@ Note: where `make -j` is written, add a number roughly equal to the amount of CP
    $ make -j
    $ sudo make install

-**2c)** or obtain and compile OCCT from https://dev.opencascade.org/release
-
 **3)** For building IfcConvert with COLLADA (.dae) support (on by default), OpenCOLLADA is needed:

    $ sudo apt-get install libpcre3-dev libxml2-dev
@@ -128,7 +141,13 @@ dependencies' paths. `OCC_INCLUDE_DIR` might be needed to set also. `OPENCOLLADA
    $ cmake ../cmake -DOCC_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu/ \
          -DOPENCOLLADA_INCLUDE_DIR="/usr/local/include/opencollada" \
          -DOPENCOLLADA_LIBRARY_DIR="/usr/local/lib/opencollada"  \
-          -DPCRE_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu/
+          -DPCRE_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu/ \
+          -DCGAL_INCLUDE_DIR=/usr/include \
+          -DGMP_INCLUDE_DIR=/usr/include \
+          -DMPFR_INCLUDE_DIR=/usr/include \
+          -DGMP_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu \
+          -DMPFR_LIBRARY_DIR=/usr/lib/x86_64-linux-gnu \
+          -DHDF5_SUPPORT=Off
    $ make -j

 If all worked out correctly you can now use IfcOpenShell. See the examples below.
@@ -60,6 +60,11 @@ if (${BUILD_CONVERT})
 OPTION(GLTF_SUPPORT "Build IfcConvert with glTF support (requires json.hpp)." OFF)
 endif()
 OPTION(USERSPACE_PYTHON_PREFIX "Installs IfcPython for the current user only instead of system-wide." OFF)
+OPTION(ADD_COMMIT_SHA "Add commit sha and branch in version number, warning results in many rebuilds, requires git" OFF)
+
+IF(NOT CMAKE_BUILD_TYPE)
+	SET(CMAKE_BUILD_TYPE "Release")
+ENDIF()

 # TODO QtViewer is deprecated ATM as it uses the 0.4 API
 # OPTION(BUILD_QTVIEWER "Build IfcOpenShell Qt GUI Viewer (requires Qt 4 framework)." OFF)
@@ -144,6 +149,7 @@ ELSE()
 	MESSAGE(FATAL_ERROR "Unable to find JSON for Modern C++ header file, aborting")
 ENDIF()
 add_definitions(-DWITH_GLTF)
+set(SWIG_DEFINES ${SWIG_DEFINES} -DWITH_GLTF)
 endif()

 # Set INSTALL_RPATH for target
@@ -200,6 +206,7 @@ find_package(LibXml2 REQUIRED)

 if (IFCXML_SUPPORT)
    add_definitions(-DWITH_IFCXML)
+	set(SWIG_DEFINES ${SWIG_DEFINES} -DWITH_IFCXML)
 endif()

 FIND_PACKAGE(Boost REQUIRED COMPONENTS ${BOOST_COMPONENTS})
@@ -371,6 +378,8 @@ IF(COLLADA_SUPPORT)
 	IF(COLLADASWStreamWriter_h)
 		MESSAGE(STATUS "OpenCOLLADA header files found")
 		ADD_DEFINITIONS(-DWITH_OPENCOLLADA)
+		set(SWIG_DEFINES ${SWIG_DEFINES} -DWITH_OPENCOLLADA)
+
 		SET(OPENCOLLADA_LIBRARY_NAMES
 			GeneratedSaxParser MathMLSolver OpenCOLLADABaseUtils OpenCOLLADAFramework OpenCOLLADASaxFrameworkLoader
 			OpenCOLLADAStreamWriter UTF buffer ftoa
@@ -439,13 +448,17 @@ if(HDF5_SUPPORT)
        else()
        	set(lib_ext a)
        endif()
+
+	if ("${CMAKE_BUILD_TYPE}" STREQUAL "Debug")
+		set(debug_postfix "_debug")
+	endif() 
        
        SET(HDF5_LIBRARIES 
-            "${HDF5_LIBRARY_DIR}/libhdf5_cpp.${lib_ext}"
-            "${HDF5_LIBRARY_DIR}/libhdf5.${lib_ext}"
-            "${HDF5_LIBRARY_DIR}/libz${zlib_post}.${lib_ext}"
-            "${HDF5_LIBRARY_DIR}/libsz.${lib_ext}"
-            "${HDF5_LIBRARY_DIR}/libaec.${lib_ext}"
+            "${HDF5_LIBRARY_DIR}/libhdf5_cpp${debug_postfix}.${lib_ext}"
+            "${HDF5_LIBRARY_DIR}/libhdf5${debug_postfix}.${lib_ext}"
+            "${HDF5_LIBRARY_DIR}/libz${zlib_post}${debug_postfix}.${lib_ext}"
+            "${HDF5_LIBRARY_DIR}/libsz${debug_postfix}.${lib_ext}"
+            "${HDF5_LIBRARY_DIR}/libaec${debug_postfix}.${lib_ext}"
        )
    endif()
    
@@ -462,12 +475,9 @@ if(HDF5_SUPPORT)
    endif()
    
    add_definitions(-DWITH_HDF5)
+	set(SWIG_DEFINES ${SWIG_DEFINES} -DWITH_HDF5)
 endif()

-IF(NOT CMAKE_BUILD_TYPE)
-	SET(CMAKE_BUILD_TYPE "Release")
-ENDIF()
-
 if(ENABLE_BUILD_OPTIMIZATIONS)
 	if(MSVC)
        # NOTE: RelWithDebInfo and Release use O2 (= /Ox /Gl /Gy/ = Og /Oi /Ot /Oy /Ob2 /Gs /GF /Gy) by default,
@@ -692,7 +702,7 @@ TARGET_LINK_LIBRARIES(IfcParse ${Boost_LIBRARIES} ${BCRYPT_LIBRARIES} ${LIBXML2_
 if (BUILD_IFCGEOM)

 # IfcGeom
-file(GLOB IFCGEOM_H_FILES ../src/ifcgeom/*.h)
+file(GLOB IFCGEOM_H_FILES ../src/ifcgeom/*.h ../src/ifcgeom/*.i)
 file(GLOB IFCGEOM_CPP_FILES ../src/ifcgeom/*.cpp)
 set(IFCGEOM_FILES ${IFCGEOM_CPP_FILES} ${IFCGEOM_H_FILES})

@@ -784,21 +794,20 @@ INSTALL(TARGETS IfcGeomServer

 endif()

+if (ADD_COMMIT_SHA)
 find_package (Git)
 if (GIT_FOUND)
 	message("git found: ${GIT_EXECUTABLE} with version ${GIT_VERSION_STRING}")
 	execute_process(
-		COMMAND ${GIT_EXECUTABLE} show -s --pretty=%D HEAD
+		COMMAND ${GIT_EXECUTABLE} branch --contains HEAD
 		OUTPUT_VARIABLE git_branches
 		OUTPUT_STRIP_TRAILING_WHITESPACE
 	)
-	string(REPLACE ", " ";" git_branch_list "${git_branches}")
-	string(REPLACE " -> " ";" git_branch_list "${git_branch_list}")
+	string(REPLACE "\n" ";" git_branch_list "${git_branches}")
 	foreach(git_branch_candidate IN ITEMS ${git_branch_list})
-		if (NOT git_branch_candidate MATCHES "/")
-			if (NOT git_branch_candidate MATCHES "^HEAD$")
-				set(git_branch ${git_branch_candidate})
-			endif()
+		string(STRIP "${git_branch_candidate}" git_branch_candidate_2)
+		if (NOT git_branch_candidate_2 MATCHES "^HEAD$")
+			set(git_branch ${git_branch_candidate_2})
 		endif()
 	endforeach()
 	execute_process(
@@ -806,11 +815,12 @@ if (GIT_FOUND)
 		OUTPUT_VARIABLE git_sha
 		OUTPUT_STRIP_TRAILING_WHITESPACE
 	)
-	message(STATUS "IfcOpenShell branch ${git_branch}")
-	message(STATUS "IfcOpenShell commit ${git_sha}")
+	message(STATUS "IfcOpenShell branch: \"${git_branch}\"")
+	message(STATUS "IfcOpenShell commit: \"${git_sha}\"")
 	add_definitions(-DIFCOPENSHELL_BRANCH=${git_branch})
 	add_definitions(-DIFCOPENSHELL_COMMIT=${git_sha})
 endif()
+endif()

 # Documentation
 IF(BUILD_DOCUMENTATION)
@@ -24,13 +24,19 @@ requirements:
    - swig >=3.0.9
    - libboost
    - icu
+    - xmlschema
+    - lxml
+    - numpy
  run:
    - libgcc  # [osx]
    - python
    - oce ==0.18.3
    - libboost
    - icu
-
+    - xmlschema
+    - lxml
+    - numpy
+    
 about:
  home: http://ifcopenshell.org
  license: LGPL
@@ -70,6 +70,7 @@ logger.addHandler(ch)

 PROJECT_NAME = "IfcOpenShell"
 USE_CURRENT_PYTHON_VERSION = os.getenv("USE_CURRENT_PYTHON_VERSION")
+ADD_COMMIT_SHA = os.getenv("ADD_COMMIT_SHA")

 PYTHON_VERSIONS = ["3.6.14", "3.7.12", "3.8.12", "3.9.7", "3.10.0"]
 JSON_VERSION = "v3.6.1"
@@ -664,13 +665,12 @@ if "cgal" in targets:
 cecho("Building IfcOpenShell:", GREEN)

 IFCOS_DIR = os.path.join(DEPS_DIR, "build", "ifcopenshell")
-if os.path.exists(IFCOS_DIR):
-    shutil.rmtree(IFCOS_DIR)
-os.makedirs(IFCOS_DIR)
-
+if os.environ.get("NO_CLEAN", "").lower() not in {"1", "on", "true"}:
+    if os.path.exists(IFCOS_DIR):
+        shutil.rmtree(IFCOS_DIR)
+os.makedirs(IFCOS_DIR, exist_ok=True)
 executables_dir = os.path.join(IFCOS_DIR, "executables")
-if not os.path.exists(executables_dir):
-    os.makedirs(executables_dir)
+os.makedirs(executables_dir, exist_ok=True)

 logger.info("\rConfiguring executables...")

@@ -692,6 +692,7 @@ cmake_args = [
    "-DGLTF_SUPPORT="                  "ON",
    "-DJSON_INCLUDE_DIR="              f"{DEPS_DIR}/install/json",
    "-DBoost_NO_BOOST_CMAKE="          "On",
+    "-DADD_COMMIT_SHA="              +("On" if ADD_COMMIT_SHA else "Off")
 ]

 if "cgal" in targets:
@@ -782,6 +783,7 @@ if "IfcOpenShell-Python" in targets:
                "-DPYTHON_INCLUDE_DIR="      +python_include,
                "-DSWIG_EXECUTABLE="         f"{DEPS_DIR}/install/swig/bin/swig",
                "-DCMAKE_INSTALL_PREFIX="    f"{DEPS_DIR}/install/ifcopenshell/tmp",
+                "-DUSERSPACE_PYTHON_PREFIX=" +["Off", "On"][os.environ.get("PYTHON_USER_SITE", "").lower() in {"1", "on", "true"}]
            ], cmake_dir=CMAKE_DIR, cwd=python_dir)

        logger.info(f"\rBuilding python {python_version} wrapper...   ")
@@ -799,7 +801,12 @@ if "IfcOpenShell-Python" in targets:

    if USE_CURRENT_PYTHON_VERSION:
        python_info = sysconfig.get_paths()
-        compile_python_wrapper(platform.python_version(), python_info["purelib"], python_info["include"], sys.executable)
+        python_lib = os.path.join(
+            sysconfig.get_config_var('LIBDIR'), 
+            sysconfig.get_config_var('multiarchsubdir').replace("/", ""), 
+            sysconfig.get_config_var("INSTSONAME")
+        )
+        compile_python_wrapper(platform.python_version(), python_lib, python_info["include"], sys.executable)
    else:
        for python_version in PYTHON_VERSIONS:
            python_library = run([bash, "-c", f"ls    {DEPS_DIR}/install/python-{python_version}/lib/libpython*.*"])
@@ -46,7 +46,7 @@ class RelatedTopic:

 class HeaderFile:
    def __init__(self):
-        self.file_name = ""
+        self.filename = ""
        self.date = None
        self.reference = ""
        self.ifc_project = None
@@ -27,6 +27,10 @@ ifeq ($(PYVERSION), py39)
 PYLIBDIR:=python3.9
 PYNUMBER:=39
 endif
+ifeq ($(PYVERSION), py310)
+PYLIBDIR:=python3.10
+PYNUMBER:=31
+endif

 ifeq ($(PLATFORM), linux)
 ifeq ($(PYVERSION), py37)
@@ -41,6 +45,12 @@ EIGENPY_URL:=https://anaconda.org/conda-forge/eigenpy/2.6.5/download/linux-64/ei
 BOOST_URL:=https://anaconda.org/conda-forge/boost/1.74.0/download/linux-64/boost-1.74.0-py39h5472131_3.tar.bz2
 LXML_URL:=https://files.pythonhosted.org/packages/19/d9/a69c6aff5673554df48120565a14a50eaa41d29ae03b02faa0b023666318/lxml-4.6.3-cp39-cp39-manylinux2014_x86_64.whl
 endif
+ifeq ($(PYVERSION), py310)
+HPPFCL_URL:=https://anaconda.org/conda-forge/hpp-fcl/1.8.0/download/linux-64/hpp-fcl-1.8.0-py310hdaf7e41_1.tar.bz2
+EIGENPY_URL:=https://anaconda.org/conda-forge/eigenpy/2.6.11/download/linux-64/eigenpy-2.6.11-py310hf3e5c9c_0.tar.bz2
+BOOST_URL:=https://anaconda.org/conda-forge/boost/1.74.0/download/linux-64/boost-1.74.0-py310h7c3ba0c_5.tar.bz2
+LXML_URL:=https://files.pythonhosted.org/packages/25/1e/19b46d8e8881fe0df2e20945d51919eeb1817836d62a90efa8506530e45c/lxml-4.8.0-cp310-cp310-manylinux_2_17_x86_64.manylinux2014_x86_64.manylinux_2_24_x86_64.whl
+endif
 ASSIMP_URL:=https://anaconda.org/conda-forge/assimp/5.0.1/download/linux-64/assimp-5.0.1-hedfc422_6.tar.bz2
 OCTOMAP_URL:=https://anaconda.org/conda-forge/octomap/1.9.7/download/linux-64/octomap-1.9.7-h4bd325d_0.tar.bz2
 ZLIB_URL:=https://anaconda.org/conda-forge/zlib/1.2.11/download/linux-64/zlib-1.2.11-h516909a_1010.tar.bz2
@@ -59,6 +69,12 @@ EIGENPY_URL:=https://anaconda.org/conda-forge/eigenpy/2.6.5/download/osx-64/eige
 BOOST_URL:=https://anaconda.org/conda-forge/boost/1.74.0/download/osx-64/boost-1.74.0-py39ha641261_3.tar.bz2
 LXML_URL:=https://files.pythonhosted.org/packages/b8/74/a71f7ad72e8db54ce899efab84507b801660750cbbfa6a39e6717557d36a/lxml-4.6.3-cp39-cp39-macosx_10_9_x86_64.whl
 endif
+ifeq ($(PYVERSION), py310)
+HPPFCL_URL:=https://anaconda.org/conda-forge/hpp-fcl/1.8.0/download/osx-64/hpp-fcl-1.8.0-py310h651ac30_1.tar.bz2
+EIGENPY_URL:=https://anaconda.org/conda-forge/eigenpy/2.6.11/download/osx-64/eigenpy-2.6.11-py310hc03097c_0.tar.bz2
+BOOST_URL:=https://anaconda.org/conda-forge/boost/1.74.0/download/osx-64/boost-1.74.0-py310h509978a_5.tar.bz2
+LXML_URL:=https://files.pythonhosted.org/packages/a1/44/17b7dac7a18807d30e2fe10c3328c152808f5464565e230bfd0e77f178c6/lxml-4.8.0-cp310-cp310-macosx_10_15_x86_64.whl
+endif
 ASSIMP_URL:=https://anaconda.org/conda-forge/assimp/5.0.1/download/osx-64/assimp-5.0.1-h1224e73_6.tar.bz2
 OCTOMAP_URL:=https://anaconda.org/conda-forge/octomap/1.9.7/download/osx-64/octomap-1.9.7-h940c156_0.tar.bz2
 ZLIB_URL:=https://anaconda.org/conda-forge/zlib/1.2.11/download/osx-64/zlib-1.2.11-h7795811_1010.tar.bz2
@@ -77,6 +93,12 @@ EIGENPY_URL:=https://anaconda.org/conda-forge/eigenpy/2.6.5/download/win-64/eige
 BOOST_URL:=https://anaconda.org/conda-forge/boost/1.74.0/download/win-64/boost-1.74.0-py39hefe7e4c_3.tar.bz2
 LXML_URL:=https://files.pythonhosted.org/packages/72/d4/426ecb8849c47c3e370c87aa0ac05d85768df917ffea27fcd6686a5e6495/lxml-4.6.3-cp39-cp39-win_amd64.whl
 endif
+ifeq ($(PYVERSION), py310)
+HPPFCL_URL:=https://anaconda.org/conda-forge/hpp-fcl/1.8.0/download/win-64/hpp-fcl-1.8.0-py310hc5a3c62_1.tar.bz2
+EIGENPY_URL:=https://anaconda.org/conda-forge/eigenpy/2.6.11/download/win-64/eigenpy-2.6.11-py310hbd43d28_0.tar.bz2
+BOOST_URL:=https://anaconda.org/conda-forge/boost/1.74.0/download/win-64/boost-1.74.0-py310hc781a3c_5.tar.bz2
+LXML_URL:=https://files.pythonhosted.org/packages/f6/71/65c80a4caa1617a4c6e8fe1500cebb179db96232e2f623bfe6a1f4294e39/lxml-4.8.0-cp310-cp310-win_amd64.whl
+endif
 ASSIMP_URL:=https://anaconda.org/conda-forge/assimp/5.0.1/download/win-64/assimp-5.0.1-hc2aa0de_6.tar.bz2
 OCTOMAP_URL:=https://anaconda.org/conda-forge/octomap/1.9.7/download/win-64/octomap-1.9.7-h5362a0b_0.tar.bz2
 ZLIB_URL:=https://anaconda.org/conda-forge/zlib/1.2.11/download/win-64/zlib-1.2.11-h62dcd97_1010.tar.bz2
@@ -93,9 +115,9 @@ endif
 	cp -r blenderbim/* dist/blenderbim/

 	# Provides IfcOpenShell Python functionality
-	cd dist/working && wget https://s3.amazonaws.com/ifcopenshell-builds/ifcblender-python-$(PYNUMBER)-v0.7.0-58ee049-$(PLATFORM)64.zip
-	cd dist/working && unzip ifcblender*
-	cp -r dist/working/io_import_scene_ifc/ifcopenshell dist/blenderbim/libs/site/packages/
+	cd dist/working && wget https://s3.amazonaws.com/ifcopenshell-builds/ifcopenshell-python-$(PYNUMBER)-v0.7.0-2985bba-$(PLATFORM)64.zip
+	cd dist/working && unzip ifcopenshell-python*
+	cp -r dist/working/ifcopenshell dist/blenderbim/libs/site/packages/

 	# See bug #812
 	cd dist/working && wget https://raw.githubusercontent.com/IfcOpenShell/IfcOpenShell/v0.7.0/src/blenderbim/occ_utils.py
@@ -133,6 +155,8 @@ endif
 	cp -r dist/working/IfcOpenShell-0.7.0/src/ifc4d/ifc4d dist/blenderbim/libs/site/packages/
 	# Provides IFC5D functionality
 	cp -r dist/working/IfcOpenShell-0.7.0/src/ifc5d/ifc5d dist/blenderbim/libs/site/packages/
+	# Provides IFCCityJSON functionality
+	cp -r dist/working/IfcOpenShell-0.7.0/src/ifccityjson dist/blenderbim/libs/site/packages/
 	rm -rf dist/working

 	# Provides Mustache templating in construction documentation
@@ -255,6 +279,15 @@ endif
 	cp -r dist/working/tqdm-4.50.0/tqdm dist/blenderbim/libs/site/packages/
 	rm -rf dist/working

+	# Required by IFCCityJSON
+	mkdir dist/working
+	cd dist/working && python -m venv env
+	cd dist/working && mkdir site-packages
+	cd dist/working && . env/bin/activate && pip install cjio --target=./site-packages
+	cd dist/working/site-packages/ && rm -r *dist-info*
+	cp -r dist/working/site-packages/* dist/blenderbim/libs/site/packages/
+	rm -rf dist/working
+
 	# Required by IFCClash
 	mkdir dist/working
 	cd dist/working && wget $(HPPFCL_URL)
@@ -360,7 +393,7 @@ endif
 	cd dist/working/ && patch ../blenderbim/libs/site/packages/behave/runner_util.py < runner_util.patch
 	rm -rf dist/working

-	# Required by ids
+	# Required by ids - uh, not any more, but I'm trying it out in the drawing module
 	mkdir dist/working
 	cd dist/working && wget $(LXML_URL)
 	cd dist/working && cp *.whl lxml.zip && unzip lxml.zip
@@ -444,6 +477,47 @@ endif
 	cd dist/working/olca-ipc-0.0.10/ && cp -r olca ../../blenderbim/libs/site/packages/
 	rm -rf dist/working

+	# Provides Brickschema fucntionality
+	mkdir dist/working
+	cd dist/working && wget https://files.pythonhosted.org/packages/ca/37/8309da9a72407d2f5eb5489c197ac3cfe96ee3ccba1902d2a0ecc7843f92/brickschema-0.5.1.tar.gz
+	cd dist/working && tar -xzvf brickschema*
+	# This is an evil hack because we don't want to bundle flask
+	echo "" > dist/working/brickschema-0.5.1/brickschema/web.py
+	cd dist/working/brickschema-0.5.1/ && cp -r brickschema ../../blenderbim/libs/site/packages/
+	# For now lets bundle the latest nightly schema
+	cd dist/working && wget https://github.com/BrickSchema/Brick/releases/download/nightly/Brick.ttl
+	cd dist/working && cp Brick.ttl ../../blenderbim/bim/schema/Brick.ttl
+	rm -rf dist/working
+
+	# Required by brickschema
+	mkdir dist/working
+	cd dist/working && wget https://files.pythonhosted.org/packages/c7/22/37bb938be8e5c20d443b0c9ba0a243573b671b01739efb0a19f81bc5b470/pyshacl-0.17.2.tar.gz
+	cd dist/working && tar -xzvf pyshacl*
+	cd dist/working/pyshacl-0.17.2/ && cp -r pyshacl ../../blenderbim/libs/site/packages/
+	rm -rf dist/working
+
+	# Required by brickschema
+	mkdir dist/working
+	cd dist/working && wget https://files.pythonhosted.org/packages/d2/a7/be8244688bfcee37c23733ab4fe8e6afa6d4403bd2674a3ae7bd2cecc77b/rdflib-6.0.2.tar.gz
+	cd dist/working && tar -xzvf rdflib*
+	cd dist/working/rdflib-6.0.2/ && cp -r rdflib ../../blenderbim/libs/site/packages/
+	rm -rf dist/working
+
+	# Required by brickschema
+	mkdir dist/working
+	cd dist/working && wget https://files.pythonhosted.org/packages/7d/c7/208aece36279e4f1236e437119358786e39530ecc1719d4e1afeddba5288/owlrl-6.0.2.tar.gz
+	cd dist/working && tar -xzvf owlrl*
+	cd dist/working/owlrl-6.0.2/ && cp -r owlrl ../../blenderbim/libs/site/packages/
+	rm -rf dist/working
+
+	# Required by brickschema
+	# This is a bit of a dodgy one, it should be provided by setuptools which Blender doesn't ship.
+	mkdir dist/working
+	cd dist/working && wget https://blenderbim.org/builds/pkg_resources.tar.gz
+	cd dist/working && tar -xzvf pkg_resources*
+	cd dist/working/ && cp -r pkg_resources ../blenderbim/libs/site/packages/
+	rm -rf dist/working
+
 	cd dist/blenderbim && sed -i "s/999999/$(VERSION)/" __init__.py
 	cd dist && zip -r blenderbim-$(VERSION)-$(PYVERSION)-$(PLATFORM).zip ./*
 	rm -rf dist/blenderbim
@@ -479,7 +553,7 @@ coverage:

 .PHONY: license
 license:
-	copyright-header --license GPL3 --copyright-holder "Dion Moult <dion@thinkmoult.com>" --copyright-year "2021" --copyright-software "BlenderBIM Add-on" --copyright-software-description "OpenBIM Blender Add-on" -a ./ -o ./
+	copyright-header --license GPL3 --copyright-holder "Dion Moult <dion@thinkmoult.com>" --copyright-year "2022" --copyright-software "BlenderBIM Add-on" --copyright-software-description "OpenBIM Blender Add-on" -a ./ -o ./

 .PHONY: clean
 clean:
@@ -1,127 +1,5 @@
-# Blender BIM IFC
+# BlenderBIM Add-on

-_Under heavy development!_
+An add-on to Blender to allow BIM functionality.

-Let's use Blender to create BIM models, because why not?
-
-## Features
-
- - IFC4 is a first-class citizen. IFC4 has been an ISO standard since 2013, with
-   the latest published in 2018. It contains many more features than IFC2X3,
-   published back in 2005.
- - Available for Windows, Mac, and Linux!
- - Use open-source Blender 2.8 to do digital modeling! Used by NASA, Hollywood,
-   and Ubisoft, Blender allows real-time modeling in rendered view, animations,
-   file linking, proxy objects, Blender Cloud collaboration, lighting analysis,
-   CFD, energy modeling, and a huge ecosystem of add-ons with a thriving
-   community. No licensing, and with a strong Python API to integrate into your
-   custom workflow.
- - Create complex spatial structures with multiple sites, buildings, facilities,
-   bridges, and building parts. Sites can be broken down into sub-sites and
-   multiple buildings per site. You can categorise different floors to different
-   buildings.
- - Classify any geometry as any IFC type. Just because it is a wall doesn't
-   mean you should be limited to modeling it in a certain way. Easily change
-   from one type to another, switch relationships and aggregations, reuse or
-   even remove geometry altogether, without damaging your geometry or breaking
-   your BIM model.
- - Use collections to create element compositions and decompositions with full
-   control over the classifications of their parts. Most BIM programs don't give
-   this flexibility. Create collection instances to efficiently duplicate
-   composite objects.
- - Allow BIM objects to instance a shared geometric representations. This allows
-   you to place the same shape in multiple objects without drastically
-   increasing your filesize.
- - Provide a custom value to any simple IFC attribute of an IFC product.
- - Create product types that regular IFC products can inherit attributes from.
- - Define your own property sets with control over exactly how the data in the
-   property sets are stored using property set template definitions which you
-   can download or create yourself. Property sets can apply to both types and
-   objects, and object property sets can selectively override type property
-   sets.
- - Applies array modifiers to create instances.
- - Basic quantity take-off support for costing.
- - Settings to toggle export of quantities or geometric representations.
-   Exporting IFC data without geometric representations is much faster and a
-   fraction of the filesize.
- - Maintain `GlobalId` between exports, so that you can manipulate the IFC
-   reliably in other software while making changes.
- - Not all objects need full solid geometry. Create representations as 2D or 3D
-   curves / wireframes for rapid and lightweight BIM development.
- - Create map conversions and coordinate reference system definitions to link
-   BIM to GIS.
- - Export basic materials with surface and diffuse colours for representation.
-   You can also link materials to an externally defined file, such as a `.blend`
-   Cycles material, V-Ray material, or even Radiance material for lighting
-   simulation.
- - Switch between different types of metric units when modeling.
- - Model multiple representations for different purposes for a single BIM
-   object or type, such as footprints, axis, reference, or clearance geometry.
-   You can export just the type of representation required for your usecase, or
-   export multiple for the user to choose from.
- - Record qualitative objectives such as design intentions, health and safety
-   strategies, or code compliance, performance solutions, and more, in the BIM
-   model and directly associate them to objects or types.
- - Classify objects and types to different classification systems such as
-   Uniclass, Omniclass, or your custom system.
- - Associate external document files such as plans, brochures, specifications,
-   warranties, or anything to objects and types.
- - Specify swept solid geometries, allowing you to round-trip geometry
-   manipulation with other BIM software which have more limited geometric tools,
-   like Revit.
- - Create material layer sets, for objects which have materials in predefined
-   layers with thicknesses.
- - Create material constituent sets, for objects which are made up of
-   arbitrarily mixed ingredients.
- - Specify nested and hosted element relationships.
- - Specify predefined door attributes as defined in the IFC4 specification.
- - Specify predefined window attributes as defined in the IFC4 specification.
- - Specify surface styles either defined as part of a material or assigned
-   directly to an object's representation.
- - Colour coding by IFC class to visually spot mistakes
-
-Some more experimental features:
-
- - Cut sections for documentation with OpenCascade
- - Export gbXML files that are linked to your IFC file to do energy analysis
- - QA module to generate Gherkin unit tests to validate your BIM models
- - HTML formatter to generate reports from QA results
- - COBie spreadsheet extraction to import into CAFM systems
-
-## Demo
-
-[See demo video](https://www.youtube.com/watch?v=iD3v3eu2AjY)
-
-It's only just started, so everything can and will change. But if you want to
-check it out:
-
- 1. Install [Blender](https://www.blender.org/) 64-bit version.
- 2. Download the latest packaged version of Blender BIM from
-    [here](https://blenderbim.org/builds/).
- 3. Launch Blender. Go to `Edit->Preferences->Add-ons->Install...`. Browse to
-    the downloaded `.zip` file from step 2.
- 4. Enable the checkbox next to the Import-Export IFC Blender plugin which will
-    show up.
- 5. All done! You will find an import and export IFC option in the `File` menu.
-
-By default, Blender BIM will export whatever you have selected. The objects you
-have selected _must_ belong in an `IfcProject` and spatially contained, such as
-witihn an `IfcBuilding`. It must also follow the naming convention. Please see
-the screenshot below for an example scene.
-
-A naming convention of `IfcClass/IfcName` is enforced. If you name your object
-`IfcWall/Foo`, it will turn into an `IfcWall` with the name attribute set to
-`Foo`. You can override object attributes using Blender's `Custom Properties`.
-Your objects must live in a top level `Collection` defined as a context class,
-usually something like `IfcProject/Foo`. You can then nest spatial structures
-underneath to create a hierarchy.
-
-## Pictures
-
-![UI](https://aws1.discourse-cdn.com/business6/uploads/buildingsmart1/original/1X/ce820c3ee22adcffae59b40f98ff23379f7e3547.png)
-
-![Blender screenshot](blender-screenshot.png)
-
-... this Blender files creates this IFC file ...
-
-![IfcOpenShell screenshot](ifcopenshell-screenshot.png)
+More information on the [BlenderBIM Add-on website](https://blenderbim.org).
@@ -43,6 +43,7 @@ modules = {
    "sequence": None,
    "group": None,
    "system": None,
+    "brick": None,
    "structural": None,
    "boundary": None,
    "profile": None,
@@ -53,6 +54,7 @@ modules = {
    "pset": None,
    "qto": None,
    "classification": None,
+    "library": None,
    "constraint": None,
    "document": None,
    "pset_template": None,
@@ -62,9 +64,13 @@ modules = {
    "bimtester": None,
    "diff": None,
    "patch": None,
+    "gis": None,
    "covetool": None,
    "augin": None,
    "debug": None,
+    # Uncomment this line to enable loading of the demo module. Happy hacking!
+    # The name "demo" must correlate to a folder name in `bim/module/`.
+    # "demo": None,
 }


@@ -73,17 +79,18 @@ for name in modules.keys():


 classes = [
-    operator.OpenUri,
-    operator.SelectDataDir,
-    operator.SelectSchemaDir,
-    operator.SelectIfcFile,
-    operator.OpenUpstream,
-    operator.AddSectionPlane,
-    operator.RemoveSectionPlane,
-    operator.ReloadIfcFile,
    operator.AddIfcFile,
-    operator.RemoveIfcFile,
+    operator.BIM_OT_add_section_plane,
+    operator.BIM_OT_remove_section_plane,
    operator.ConfigureVisibility,
+    operator.OpenUpstream,
+    operator.OpenUri,
+    operator.ReloadIfcFile,
+    operator.RemoveIfcFile,
+    operator.SelectDataDir,
+    operator.SelectIfcFile,
+    operator.SelectSchemaDir,
+    operator.SelectURIAttribute,
    prop.StrProperty,
    prop.ObjProperty,
    prop.Attribute,
@@ -99,6 +106,22 @@ classes = [
    ui.BIM_UL_generic,
    ui.BIM_UL_topics,
    ui.BIM_ADDON_preferences,
+    # Scene panel groups
+    ui.BIM_PT_project_info,
+    ui.BIM_PT_project_setup,
+    ui.BIM_PT_collaboration,
+    ui.BIM_PT_geometry,
+    ui.BIM_PT_services,
+    ui.BIM_PT_structural,
+    ui.BIM_PT_4D5D,
+    ui.BIM_PT_quality_control,
+    ui.BIM_PT_integrations,
+    # Object panel groups
+    ui.BIM_PT_object_metadata,
+    ui.BIM_PT_geometry_object,
+    ui.BIM_PT_services_object,
+    ui.BIM_PT_utilities_object,
+    ui.BIM_PT_misc_object,
 ]

 for mod in modules.values():
@@ -1,10 +1,44 @@
 <link href="jsgantt.css" rel="stylesheet" type="text/css"/>
 <script src="jsgantt.js" type="text/javascript"></script>
+<style>
+.gtaskcellwkend,
+.gtaskcellcurrent,
+.gminorheadingwkend {
+  background-color: #e1e1e1;
+}
+
+.gitemhighlight td {
+  background-color: #ffdaaa;
+}
+
+.gtaskblue {
+  background: #4281A4;
+}
+
+.gtaskred {
+  background: #C1666B;
+}
+
+.gtaskgreen {
+  background: #48A9A6;
+}
+
+.gtaskyellow {
+  background: #D4B483;
+}
+
+.gmainleft {
+  overflow: visible;
+  flex: 0 1 auto;
+}
+
+</style>
+<a href="#print" id="print">Print Mode</a>
 <div style="position:relative" class="gantt" id="GanttChartDIV"></div>
 <script type="text/javascript">
 var g = new JSGantt.GanttChart(document.getElementById('GanttChartDIV'), 'day');
 g.setOptions({
-    vCaptionType: 'Complete',  // Set to Show Caption : None,Caption,Resource,Duration,Complete,
+    vCaptionType: 'Caption',  // Set to Show Caption : None,Caption,Resource,Duration,Complete,
    vQuarterColWidth: 36,
    vDateTaskDisplayFormat: 'day dd month yyyy', // Shown in tool tip box
    vDayMajorDateDisplayFormat: 'mon yyyy - Week ww',// Set format to dates in the "Major" header of the "Day" view
@@ -14,7 +48,16 @@ g.setOptions({
    vShowEndWeekDate: 0,  // Show/Hide the date for the last day of the week in header for daily
    vUseSingleCell: 10000, // Set the threshold cell per table row (Helps performance for large data.
    vFormatArr: ['Day', 'Week', 'Month', 'Quarter'], // Even with setUseSingleCell using Hour format on such a large chart can cause issues in some browsers,
-    vTotalHeight: 1000,
+    vShowRes: false, // Disable the resource column.
+    vShowComp: false, // Disable the completion column.
+    vShowDur: false, // Disable the duration column, because jsgantt doesn't calculate durations the way we want.
+    vAdditionalHeaders: {ifcduration: {title: 'Duration'}},
+    vUseToolTip: false, // Disable tooltips.
+    vTotalHeight: 900,
+});
+document.getElementById('print').addEventListener('click', function() {
+    g.setTotalHeight("");
+    g.Draw();
 });
 var json_data = `
 {{{json_data}}}
@@ -0,0 +1,16 @@
+ISO-10303-21;
+HEADER;
+FILE_DESCRIPTION((),'2;1');
+FILE_NAME('EPset_Drawing.ifc','2020-01-01T00:00:00',(),(),'EPset_Drawing','EPset_Drawing',$);
+FILE_SCHEMA(('IFC4'));
+ENDSEC;
+DATA;
+#1=IFCPROPERTYSETTEMPLATE('2JhNIvqZrFnAgxfhK0XVQX',$,'EPset_Drawing','',.PSET_OCCURRENCEDRIVEN.,'IfcAnnotation',(#2,#3,#4,#5,#6,#7));
+#2=IFCSIMPLEPROPERTYTEMPLATE('23JavTMk98ZxXhrUEnjAcf',$,'TargetView','',.P_SINGLEVALUE.,'IfcLabel',$,$,$,$,$,.READWRITE.);
+#3=IFCSIMPLEPROPERTYTEMPLATE('1yVWUt5H9DAOuu0OaMMLpe',$,'Scale','',.P_SINGLEVALUE.,'IfcLabel',$,$,$,$,$,.READWRITE.);
+#4=IFCSIMPLEPROPERTYTEMPLATE('3gsuPBtU93b8f0gg1pjkq6',$,'HumanScale','',.P_SINGLEVALUE.,'IfcLabel',$,$,$,$,$,.READWRITE.);
+#5=IFCSIMPLEPROPERTYTEMPLATE('0AK5C2UpL4$eaac2LszAx$',$,'HasUnderlay','',.P_SINGLEVALUE.,'IfcBoolean',$,$,$,$,$,.READWRITE.);
+#6=IFCSIMPLEPROPERTYTEMPLATE('2j2ZEZR8X5tONm7kli5hM6',$,'HasLinework','',.P_SINGLEVALUE.,'IfcBoolean',$,$,$,$,$,.READWRITE.);
+#7=IFCSIMPLEPROPERTYTEMPLATE('1ttChRysH9UuEX2FeMj5Hu',$,'HasAnnotation','',.P_SINGLEVALUE.,'IfcBoolean',$,$,$,$,$,.READWRITE.);
+ENDSEC;
+END-ISO-10303-21;
@@ -19,14 +19,26 @@
 */

 * { stroke-linecap: round; stroke-linejoin: round; }
-*[id] { fill: black; stroke: black; stroke-linecap: 'round'; stroke-width: 0.35; }
 text { fill: black; stroke: none; }
+.cut { fill: black; stroke: black; stroke-linecap: 'round'; stroke-width: 0.35; fill-rule: evenodd; }
 .projection { fill: white; stroke: black; stroke-linecap: 'round'; stroke-width: 0.25; }
 .annotation { fill: none; stroke: black; stroke-linecap: 'round'; stroke-width: 0.25; }
-.hidden { stroke-dasharray: 3, 2; }
 .solid {}
-.leader { marker-end: url(#leader-marker); }
-.stair { marker-start: url(#stair-marker-start); marker-end: url(#stair-marker-end); }
+.IfcAnnotation { fill: none; stroke: black; stroke-linecap: 'round'; stroke-width: 0.25; }
+.PredefinedType-MISC { stroke: black; stroke-width: 0.25; }
+.PredefinedType-BACKGROUND { stroke: black; stroke-width: 0.18; }
+.PredefinedType-GRID { marker-start: url(#grid-marker); marker-end: url(#grid-marker); }
+.PredefinedType-SECTIONLEVEL { marker-start: url(#section-level-marker); stroke-dasharray: 12.5, 3, 3, 3; }
+.PredefinedType-PLANLEVEL { marker-end: url(#plan-level-marker); }
+.PredefinedType-DIMENSION { marker-start: url(#dimension-marker-start); marker-end: url(#dimension-marker-end); }
+.PredefinedType-HIDDENLINE { stroke-dasharray: 3, 2; }
+.PredefinedType-STAIR { marker-start: url(#stair-marker-start); marker-end: url(#stair-marker-end); }
+.PredefinedType-BOUNDARY { fill: none; stroke: red; stroke-width: 1; stroke-dasharray: 12, 4, 3, 4, 3, 4; }
+.PredefinedType-BATTING { marker-start: url(#batting); stroke: none; }
+.PredefinedType-SEALANT { fill: url(#crosshatch1); stroke-width: 0.25; }
+.PredefinedType-TEXT { fill: black; stroke: none; }
+path.PredefinedType-TEXTLEADER { marker-end: url(#leader-marker); }
+text.PredefinedType-TEXTLEADER { fill: black; stroke: none; }
 .break { fill: white; }
 .breakline { fill: none; stroke: black; stroke-linecap: 'round'; stroke-width: 0.25; marker-mid: url(#breakline-marker); }
 .material-blank { fill: white; }
@@ -44,5 +56,9 @@ text { fill: black; stroke: none; }
 .material-honeycomb { fill: url(#honeycomb); }
 .material-sand { fill: url(#sand); }
 .material-concrete { fill: url(#concrete); stroke-width: 0.5; }
-.material-boundary { fill: none; stroke: red; stroke-width: 1; stroke-dasharray: 12,4,3,4,3,4; }
 .IfcSpace { fill: none; stroke: none; }
+.PredefinedType-STUD { stroke: black; stroke-width: 1; }
+.PredefinedType-WOOD { fill: url(#wood); stroke: black; stroke-width: 0.5; }
+.PredefinedType-STEEL { fill: url(#steel); stroke: black; stroke-width: 0.5; }
+.PredefinedType-CONCRETE { fill: url(#concrete); stroke: black; stroke-width: 0.5; }
+.PredefinedType-PLASTERBOARD { fill: url(#sand); stroke: black; stroke-width: 0.25; }
@@ -1,5 +1,9 @@
 <?xml version="1.0" encoding="utf-8" ?>
 <svg baseProfile="full" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:ev="http://www.w3.org/2001/xml-events" xmlns:xlink="http://www.w3.org/1999/xlink">
+    <marker id="batting" markerHeight="10" markerWidth="4" orient="auto" refX="0" refY="5" markerUnits="userSpaceOnUse">
+        <!-- Tip: https://svg-path-visualizer.netlify.app/ -->
+        <path style="fill: none; stroke:black; stroke-width:0.18" d="M 0 2 A 2 2 0 0 1 4 2 L 2 8 M 0 2 L 2 8 A 2 2 0 0 0 4 10 M 2 8 A 2 2 0 0 1 0 10" />
+    </marker>
    <marker id="eng-dimension-marker-start" markerHeight="14" markerWidth="11" orient="auto" refX="1" refY="7">
        <g>
            <path d="M 11 3.5 L 11 10.5 L 1 7" class="annotation" style="fill:black;" />
@@ -3,6 +3,10 @@
 <pattern id="demolish" width="1" height="1" patternTransform="rotate(45 0 0)" patternUnits="userSpaceOnUse">
    <line x1="0" y1="0" x2="0" y2="1" style="stroke:red; stroke-width:0.25" />
 </pattern>
+<pattern id="steel" width="3" height="1" patternTransform="rotate(45 0 0)" patternUnits="userSpaceOnUse">
+    <line x1="0" y1="0" x2="0" y2="1" style="stroke:black; stroke-width:0.25" />
+    <line x1="1" y1="0" x2="1" y2="1" style="stroke:black; stroke-width:0.25" />
+</pattern>
 <pattern id="diagonal1" width="1" height="1" patternTransform="rotate(45 0 0)" patternUnits="userSpaceOnUse">
    <line x1="0" y1="0" x2="0" y2="1" style="stroke:black; stroke-width:0.25" />
 </pattern>
@@ -80,6 +84,9 @@
    <path d="M 1.25,2.165 L 2.5,4.33 L 5,4.33 L 6.25,2.165 L 5,0 L 2.5,0 L 1.25,2.165" style="stroke:black;stroke-width:0.25;stroke-linecap:round;fill:none" />
    <path d="M 6.25,2.165 L 7.5,2.165" style="stroke:black;stroke-width:0.25;stroke-linecap:round" />
 </pattern>
+<pattern id="wood" width="50" height="50" patternUnits="userSpaceOnUse">
+    <path style="fill:none; stroke: black; stroke-width:0.25;" d="M 49.649999,1.3460737 A 69.019995,69.019995 0 0 0 48.653938,0.34999949 M 49.649999,4.9389583 A 66.554994,66.554994 0 0 0 45.06105,0.34999949 M 49.649999,8.6983527 A 64.089999,64.089999 0 0 0 41.301656,0.34999949 M 49.649999,12.675003 A 61.624998,61.624998 0 0 0 37.325,0.34999949 M 49.649999,16.948067 A 59.159997,59.159997 0 0 0 33.05192,0.34999949 M 49.649999,21.652972 A 56.694997,56.694997 0 0 0 28.347017,0.34999949 M 49.649999,27.057906 A 54.229999,54.229999 0 0 0 22.942096,0.34999949 M 49.649999,33.866298 A 51.764998,51.764998 0 0 0 16.1337,0.34999949 M 49.649999,49.649989 A 49.299997,49.299997 0 0 0 0.34999949,0.34999949 M 47.185,49.649989 A 46.834999,46.834999 0 0 0 0.34999949,2.8149951 M 44.72,49.649989 A 44.369998,44.369998 0 0 0 0.34999949,5.2799906 M 42.254999,49.649989 A 41.904997,41.904997 0 0 0 0.34999949,7.7450123 M 39.790001,49.649989 A 39.439999,39.439999 0 0 0 0.34999949,10.210008 M 37.325,49.649989 A 36.974998,36.974998 0 0 0 0.34999949,12.675003 M 34.859999,49.649989 A 34.509998,34.509998 0 0 0 0.34999949,15.139998 M 32.395001,49.649989 A 32.044999,32.044999 0 0 0 0.34999949,17.604994 M 29.93,49.649989 A 29.579999,29.579999 0 0 0 0.34999949,20.069989 M 27.465,49.649989 A 27.114998,27.114998 0 0 0 0.34999949,22.535011 M 24.999997,49.649989 A 24.649999,24.649999 0 0 0 0.34999949,25.000007 M 22.534998,49.649989 A 22.184999,22.184999 0 0 0 0.34999949,27.465003 M 20.069998,49.649989 A 19.719999,19.719999 0 0 0 0.34999949,29.929999 M 17.604998,49.649989 A 17.254999,17.254999 0 0 0 0.34999949,32.394994 M 15.139998,49.649989 A 14.789999,14.789999 0 0 0 0.34999949,34.85999 M 12.674999,49.649989 A 12.325,12.325 0 0 0 0.34999949,37.325011 M 10.209999,49.649989 A 9.8599994,9.8599994 0 0 0 0.34999949,39.790007 M 7.7449994,49.649989 A 7.3949999,7.3949999 0 0 0 0.34999949,42.255002 M 5.2799992,49.649989 A 4.9299997,4.9299997 0 0 0 0.34999949,44.719998 M 2.8149995,49.649989 A 2.4649999,2.4649999 0 0 0 0.34999949,47.184993 M 0.34999949,49.649989 H 3.8010003 M 0.34999949,49.649989 H 3.8010003 M 0.34999949,49.649989 H 3.8010003" />
+</pattern>
 <pattern id="sand" width="50" height="50" patternUnits="userSpaceOnUse">
    <path style="fill: white;" d="M 0 0 50 0 50 50 0 50" />
    <path
@@ -5,6 +5,20 @@
    </g>
    <g id="door-tag">
        <circle cy="1.75" r="5" fill="white" stroke="black" style="stroke-width: 0.25;" />
-        <line x1="-5" y1="1.75" x2="5" y2="1.75" style="stroke:black; stroke-width: 0.25;" />
+        <line x1="-5" y1="1.75" x2="5" y2="1.75" style="stroke: black; stroke-width: 0.25;" />
+    </g>
+    <g id="elevation-arrow">
+        <path style="fill: black;" d="M -7.07106 0 0 -7.07106 7.07106 0" />
+    </g>
+    <g id="elevation-tag">
+        <circle r="5" fill="white" stroke="black" style="stroke-width: 0.25;" />
+        <line x1="-5" y1="0" x2="5" y2="0" style="stroke: black; stroke-width: 0.25;" />
+    </g>
+    <g id="section-arrow">
+        <path style="fill: black;" d="M -7.07106 0 0 -7.07106 7.07106 0" />
+    </g>
+    <g id="section-tag">
+        <circle r="5" fill="white" stroke="black" style="stroke-width: 0.25;" />
+        <line x1="-5" y1="0" x2="5" y2="0" style="stroke: black; stroke-width: 0.25;" />
    </g>
 </svg>
@@ -173,7 +173,7 @@
         style="stroke-width:0.999999px"
         y="1036.1166"
         x="3030.9653"
-         id="tspan2527">{{revision}}</tspan></text>
+         id="tspan2527">{{Revision}}</tspan></text>
    <text
       xml:space="preserve"
       style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:13.3918px;line-height:125%;font-family:'OpenGost Type B TT';-inkscape-font-specification:'OpenGost Type B TT';font-variant-ligatures:normal;font-variant-caps:normal;font-variant-numeric:normal;font-feature-settings:normal;text-align:start;letter-spacing:0px;word-spacing:0px;writing-mode:lr-tb;text-anchor:start;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.999999px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1"
@@ -183,7 +183,7 @@
         id="tspan2531"
         x="2804.7021"
         y="1036.1166"
-         style="stroke-width:0.999999px">{{number}}</tspan></text>
+         style="stroke-width:0.999999px">{{Identification}} - {{Name}}</tspan></text>
  </g>
  <g
     transform="matrix(0.26458333,0,0,0.26458334,-3.180917e-5,297.00003)"
@@ -169,7 +169,7 @@
       style="stroke-width:0.264583px"
       y="397.13919"
       x="554.94287"
-       id="tspan2527">{{revision}}</tspan></text>
+       id="tspan2527">{{Revision}}</tspan></text>
  <text
     xml:space="preserve"
     style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:3.54325px;line-height:125%;font-family:'OpenGost Type B TT';-inkscape-font-specification:'OpenGost Type B TT';font-variant-ligatures:normal;font-variant-caps:normal;font-variant-numeric:normal;font-feature-settings:normal;text-align:start;letter-spacing:0px;word-spacing:0px;writing-mode:lr-tb;text-anchor:start;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.264583px;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dasharray:none;stroke-opacity:1"
@@ -179,7 +179,7 @@
       id="tspan2531"
       x="495.07742"
       y="397.13919"
-       style="stroke-width:0.264583px">{{number}}</tspan></text>
+       style="stroke-width:0.264583px">{{Identification}} - {{Name}}</tspan></text>
  <g
     style="stroke-width:3.77953"
     id="g90669"
@@ -172,7 +172,7 @@
         id="tspan2527"
         x="544.94287"
         y="284.13919"
-         style="stroke-width:0.264583px">{{revision}}</tspan></text>
+         style="stroke-width:0.264583px">{{Revision}}</tspan></text>
    <text
       id="text2533"
       y="284.13919"
@@ -182,7 +182,7 @@
         style="stroke-width:0.264583px"
         y="284.13919"
         x="485.07742"
-         id="tspan2531">{{number}}</tspan></text>
+         id="tspan2531">{{Identification}} - {{Name}}</tspan></text>
  </g>
  <g
     style="stroke-width:3.77953"
@@ -70,7 +70,7 @@
         style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:4.96055365px;font-family:'OpenGost Type B TT';-inkscape-font-specification:'OpenGost Type B TT';text-align:center;text-anchor:middle;stroke-width:0.26458332px"
         y="103.10933"
         x="32.822662"
-         id="tspan857">{{no}}</tspan></text>
+         id="tspan857">{{Identification}}</tspan></text>
    <text
       xml:space="preserve"
       style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:17.71626091px;line-height:125%;font-family:Arial;-inkscape-font-specification:Arial;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.26458329px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1"
@@ -80,7 +80,7 @@
         id="tspan861"
         x="39.12896"
         y="100.19173"
-         style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:3.54325247px;font-family:'OpenGost Type B TT';-inkscape-font-specification:'OpenGost Type B TT';text-align:start;text-anchor:start;stroke-width:0.26458329px">{{name}}</tspan></text>
+         style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:3.54325247px;font-family:'OpenGost Type B TT';-inkscape-font-specification:'OpenGost Type B TT';text-align:start;text-anchor:start;stroke-width:0.26458329px">{{Name}}</tspan></text>
    <text
       id="text867"
       y="105.0553"
@@ -90,6 +90,6 @@
         style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:3.54325247px;font-family:'OpenGost Type B TT';-inkscape-font-specification:'OpenGost Type B TT';text-align:start;text-anchor:start;stroke-width:0.26458332px"
         y="105.0553"
         x="39.285267"
-         id="tspan865">{{scale}}</tspan></text>
+         id="tspan865">{{Scale}}</tspan></text>
  </g>
 </svg>
@@ -28,10 +28,12 @@ import ifcopenshell
 import ifcopenshell.api
 import ifcopenshell.util.placement
 import blenderbim.tool as tool
+import blenderbim.core.geometry
 import blenderbim.core.aggregate
 import blenderbim.core.spatial
 import blenderbim.core.style
 from blenderbim.bim.ifc import IfcStore
+from mathutils import Vector


 class IfcExporter:
@@ -41,20 +43,22 @@ class IfcExporter:
    def export(self):
        self.file = IfcStore.get_file()
        self.set_header()
+        IfcStore.update_cache()
        if bpy.context.scene.BIMProjectProperties.is_authoring:
-            self.sync_object_placements_and_deletions()
+            self.sync_deletions()
+            self.sync_all_objects()
            self.sync_edited_objects()
-        extension = self.ifc_export_settings.output_file.split(".")[-1]
+        extension = self.ifc_export_settings.output_file.split(".")[-1].lower()
        if extension == "ifczip":
            with tempfile.TemporaryDirectory() as unzipped_path:
                filename, ext = os.path.splitext(os.path.basename(self.ifc_export_settings.output_file))
-                tmp_name = "{}.ifc".format(filename)
-                tmp_file = os.path.join(unzipped_path, tmp_name)
+                tmp_filename = f"{filename}.ifc"
+                tmp_file = os.path.join(unzipped_path, tmp_filename)
                self.file.write(tmp_file)
                with zipfile.ZipFile(
                    self.ifc_export_settings.output_file, mode="w", compression=zipfile.ZIP_DEFLATED, compresslevel=9
                ) as zf:
-                    zf.write(tmp_file)
+                    zf.write(tmp_file, arcname=tmp_filename)
        elif extension == "ifc":
            self.file.write(self.ifc_export_settings.output_file)
        elif extension == "ifcjson":
@@ -83,27 +87,39 @@ class IfcExporter:
            self.get_application_name(), self.get_application_version()
        )

-    def sync_object_placements_and_deletions(self):
-        self.unit_scale = ifcopenshell.util.unit.calculate_unit_scale(self.file)
-        to_delete = []
+    def sync_deletions(self):
+        results = []
+        for ifc_definition_id in IfcStore.deleted_ids:
+            try:
+                product = self.file.by_id(ifc_definition_id)
+                if hasattr(product, "GlobalId"):
+                    results.append(product.GlobalId)
+            except:
+                continue
+            ifcopenshell.api.run("root.remove_product", self.file, **{"product": product})
+        return results

-        for ifc_definition_id, obj in IfcStore.id_map.items():
+    def sync_all_objects(self):
+        results = []
+        self.unit_scale = ifcopenshell.util.unit.calculate_unit_scale(self.file)
+        for ifc_definition_id in list(IfcStore.id_map.keys()):
+            obj = IfcStore.id_map[ifc_definition_id]
            try:
                if isinstance(obj, bpy.types.Material):
                    continue
                tool.Collector.sync(obj)
-                self.sync_object_placement(obj)
+                result = self.sync_object_placement(obj)
+                if result:
+                    results.append(result)
+                result = self.sync_object_material(obj)
+                if result:
+                    results.append(result)
            except ReferenceError:
                pass  # The object is likely deleted
-            if self.should_delete(obj):
-                to_delete.append(ifc_definition_id)
-
-        for ifc_definition_id in to_delete:
-            product = self.file.by_id(ifc_definition_id)
-            IfcStore.unlink_element(product)
-            ifcopenshell.api.run("root.remove_product", self.file, **{"product": product})
+        return results

    def sync_edited_objects(self):
+        results = []
        for obj in IfcStore.edited_objs.copy():
            if not obj:
                continue
@@ -111,35 +127,51 @@ class IfcExporter:
                if isinstance(obj, bpy.types.Material):
                    blenderbim.core.style.update_style_colours(tool.Ifc, tool.Style, obj=obj)
                else:
+                    element = tool.Ifc.get_entity(obj)
+                    if element:
+                        results.append(element)
                    bpy.ops.bim.update_representation(obj=obj.name)
            except ReferenceError:
                pass  # The object is likely deleted
        IfcStore.edited_objs.clear()
+        return results
+
+    def sync_object_material(self, obj):
+        if not obj.data or not isinstance(obj.data, bpy.types.Mesh):
+            return
+        if not self.has_changed_materials(obj):
+            return
+        bpy.ops.bim.update_representation(obj=obj.name)
+
+    def has_changed_materials(self, obj):
+        checksum = obj.data.BIMMeshProperties.material_checksum
+        return checksum != str([s.id() for s in tool.Geometry.get_styles(obj) if s])

    def sync_object_placement(self, obj):
+        if not self.has_object_moved(obj):
+            return
        blender_matrix = np.array(obj.matrix_world)
        element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        if (obj.scale - Vector((1.0, 1.0, 1.0))).length > 1e-4:
+            bpy.ops.bim.update_representation(obj=obj.name)
+            return element
        if element.is_a("IfcGridAxis"):
            return self.sync_grid_axis_object_placement(obj, element)
        if not hasattr(element, "ObjectPlacement"):
            return
-        ifc_matrix = ifcopenshell.util.placement.get_local_placement(element.ObjectPlacement)
-        ifc_matrix[0][3] *= self.unit_scale
-        ifc_matrix[1][3] *= self.unit_scale
-        ifc_matrix[2][3] *= self.unit_scale
+        blenderbim.core.geometry.edit_object_placement(tool.Ifc, tool.Geometry, tool.Surveyor, obj=obj)
+        return element

-        props = bpy.context.scene.BIMGeoreferenceProperties
-        if props.has_blender_offset and obj.BIMObjectProperties.blender_offset_type == "OBJECT_PLACEMENT":
-            ifc_matrix = ifcopenshell.util.geolocation.global2local(
-                ifc_matrix,
-                float(props.blender_eastings) * self.unit_scale,
-                float(props.blender_northings) * self.unit_scale,
-                float(props.blender_orthogonal_height) * self.unit_scale,
-                float(props.blender_x_axis_abscissa),
-                float(props.blender_x_axis_ordinate),
-            )
-        if not np.allclose(ifc_matrix, blender_matrix, atol=0.0001):
-            blenderbim.core.geometry.edit_object_placement(tool.Ifc, tool.Surveyor, obj=obj)
+    def has_object_moved(self, obj):
+        if not obj.BIMObjectProperties.location_checksum:
+            return True  # Let's be conservative
+        loc_check = np.frombuffer(eval(obj.BIMObjectProperties.location_checksum))
+        rot_check = np.frombuffer(eval(obj.BIMObjectProperties.rotation_checksum))
+        loc_real = np.array(obj.matrix_world.translation).flatten()
+        rot_real = np.array(obj.matrix_world.to_3x3()).flatten()
+        if np.allclose(loc_check, loc_real, atol=1e-4) and np.allclose(rot_check, rot_real, atol=1e-2):
+            return False
+        return True

    def sync_grid_axis_object_placement(self, obj, element):
        grid = (element.PartOfU or element.PartOfV or element.PartOfW)[0]
@@ -148,15 +180,7 @@ class IfcExporter:
            self.sync_object_placement(grid_obj)
            if grid_obj.matrix_world != obj.matrix_world:
                bpy.ops.bim.update_representation(obj=obj.name)
-
-    def should_delete(self, obj):
-        try:
-            # This will throw an exception if the Blender object no longer exists
-            foo = obj.name
-            foo
-            return False
-        except:
-            return True
+        tool.Geometry.record_object_position(obj)

    def get_application_name(self):
        return "BlenderBIM"
@@ -26,9 +26,7 @@ from blenderbim.bim.module.drawing.prop import RasterStyleProperty
 from bpy.app.handlers import persistent
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.module.owner.prop import get_user_person, get_user_organisation
-from ifcopenshell.api.attribute.data import Data as AttributeData
 from ifcopenshell.api.material.data import Data as MaterialData
-from ifcopenshell.api.style.data import Data as StyleData
 from ifcopenshell.api.type.data import Data as TypeData


@@ -68,11 +66,10 @@ def name_callback(obj, data):
    if isinstance(obj, bpy.types.Material):
        if obj.BIMObjectProperties.ifc_definition_id:
            IfcStore.get_file().by_id(obj.BIMObjectProperties.ifc_definition_id).Name = obj.name
-            AttributeData.load(IfcStore.get_file(), obj.BIMObjectProperties.ifc_definition_id)
            MaterialData.load_materials()
        if obj.BIMMaterialProperties.ifc_style_id:
            IfcStore.get_file().by_id(obj.BIMMaterialProperties.ifc_style_id).Name = obj.name
-            StyleData.load(IfcStore.get_file(), obj.BIMMaterialProperties.ifc_style_id)
+        refresh_ui_data()
        return

    if not obj.BIMObjectProperties.ifc_definition_id or "/" not in obj.name:
@@ -96,7 +93,7 @@ def name_callback(obj, data):
    if element.is_a("IfcTypeProduct"):
        TypeData.purge()
    element.Name = "/".join(obj.name.split("/")[1:])
-    AttributeData.load(IfcStore.get_file(), obj.BIMObjectProperties.ifc_definition_id)
+    refresh_ui_data()


 def color_callback(obj, data):
@@ -160,12 +157,12 @@ def loadIfcStore(scene):
    if not IfcStore.get_file():
        return
    IfcStore.get_schema()
-    IfcStore.reload_linked_elements()
+    IfcStore.relink_all_objects()


@persistent
 def undo_pre(scene):
-    IfcStore.update_undo_redo_stack_objects()
+    IfcStore.track_undo_redo_stack_object_map()


@persistent
@@ -174,13 +171,13 @@ def undo_post(scene):
        IfcStore.last_transaction = bpy.context.scene.BIMProperties.last_transaction
        IfcStore.undo()
        purge_module_data()
-    IfcStore.update_undo_redo_stack_objects()
-    IfcStore.reload_linked_elements(objects=[bpy.data.objects.get(o) for o in IfcStore.undo_redo_stack_objects])
+    IfcStore.track_undo_redo_stack_selected_objects()
+    IfcStore.reload_undo_redo_stack_objects()


@persistent
 def redo_pre(scene):
-    IfcStore.update_undo_redo_stack_objects()
+    IfcStore.track_undo_redo_stack_object_map()


@persistent
@@ -189,8 +186,8 @@ def redo_post(scene):
        IfcStore.last_transaction = bpy.context.scene.BIMProperties.last_transaction
        IfcStore.redo()
        purge_module_data()
-    IfcStore.update_undo_redo_stack_objects()
-    IfcStore.reload_linked_elements(objects=[bpy.data.objects.get(o) for o in IfcStore.undo_redo_stack_objects])
+    IfcStore.track_undo_redo_stack_selected_objects()
+    IfcStore.reload_undo_redo_stack_objects()


@persistent
@@ -236,6 +233,7 @@ def setDefaultProperties(scene):
    )
    ifcopenshell.api.owner.settings.get_user = lambda ifc: core_owner.get_user(tool.Owner)
    ifcopenshell.api.owner.settings.get_application = get_application
+    # TODO: Move to drawing module
    if len(bpy.context.scene.DocProperties.drawing_styles) == 0:
        drawing_style = bpy.context.scene.DocProperties.drawing_styles.add()
        drawing_style.name = "Technical"
@@ -289,7 +287,7 @@ def setDefaultProperties(scene):
                RasterStyleProperty.SHADING_SHADOW_INTENSITY.value: 0.5,
                RasterStyleProperty.DISPLAY_LIGHT_DIRECTION.value: (0.5, 0.5, 0.5),
                RasterStyleProperty.VIEW_USE_CURVE_MAPPING.value: False,
-                RasterStyleProperty.OVERLAY_SHOW_WIREFRAMES.value: True,
+                RasterStyleProperty.OVERLAY_SHOW_WIREFRAMES.value: False,
                RasterStyleProperty.OVERLAY_WIREFRAME_THRESHOLD.value: 0,
                RasterStyleProperty.OVERLAY_SHOW_FLOOR.value: False,
                RasterStyleProperty.OVERLAY_SHOW_AXIS_X.value: False,
@@ -19,6 +19,7 @@
 import bpy
 import json
 import math
+import zipfile
 import ifcopenshell
 import ifcopenshell.util.attribute
 from mathutils import geometry
@@ -47,6 +48,9 @@ def draw_attribute(attribute, layout, copy_operator=None):
    if copy_operator:
        op = layout.operator(f"{copy_operator}", text="", icon="COPYDOWN")
        op.name = attribute.name
+    if attribute.is_uri:
+        op = layout.operator("bim.select_uri_attribute", text="", icon="FILE_FOLDER")
+        op.data_path = attribute.path_from_id("string_value")


 def import_attributes(ifc_class, props, data, callback=None):
@@ -77,6 +81,8 @@ def import_attribute(attribute, props, data, callback=None):
        props.remove(len(props) - 1)
    elif data_type == "string":
        new.string_value = "" if new.is_null else data[attribute.name()]
+        if attribute.type_of_attribute().declared_type().name() == "IfcURIReference":
+            new.is_uri = True
    elif data_type == "boolean":
        new.bool_value = False if new.is_null else data[attribute.name()]
    elif data_type == "integer":
@@ -97,3 +103,45 @@ def export_attributes(props, callback=None):
            continue  # Our job is done
        attributes[prop.name] = prop.get_value()
    return attributes
+
+
+class IfcHeaderExtractor:
+    def __init__(self, filepath: str):
+        self.filepath = filepath
+
+    def extract(self):
+        extension = self.filepath.split(".")[-1]
+        if extension.lower() == "ifc":
+            with open(self.filepath) as ifc_file:
+                return self.extract_ifc_spf(ifc_file)
+        elif extension.lower() == "ifczip":
+            return self.extract_ifc_zip()
+
+    def extract_ifc_spf(self, ifc_file):
+        # https://www.steptools.com/stds/step/IS_final_p21e3.html#clause-8
+        data = {}
+        max_lines_to_parse = 50
+        for _ in range(max_lines_to_parse):
+            line = next(ifc_file)
+            if isinstance(line, bytes):
+                line = line.decode("utf-8")
+            if line.startswith("FILE_DESCRIPTION"):
+                for i, part in enumerate(line.split("'")):
+                    if i == 1:
+                        data["description"] = part
+                    elif i == 3:
+                        data["implementation_level"] = part
+            elif line.startswith("FILE_NAME"):
+                for i, part in enumerate(line.split("'")):
+                    if i == 1:
+                        data["name"] = part
+                    elif i == 3:
+                        data["time_stamp"] = part
+            elif line.startswith("FILE_SCHEMA"):
+                data["schema_name"] = line.split("'")[1]
+                break
+        return data
+
+    def extract_ifc_zip(self):
+        archive = zipfile.ZipFile(self.filepath, "r")
+        return self.extract_ifc_spf(archive.open(archive.filelist[0]))
@@ -1,5 +1,5 @@
 # BlenderBIM Add-on - OpenBIM Blender Add-on
-# Copyright (C) 2020, 2021 Dion Moult <dion@thinkmoult.com>
+# Copyright (C) 2020, 2021, 2022 Dion Moult <dion@thinkmoult.com>
 #
 # This file is part of BlenderBIM Add-on.
 #
@@ -16,8 +16,10 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

+import os
 import bpy
 import uuid
+import hashlib
 import zipfile
 import tempfile
 import ifcopenshell
@@ -29,8 +31,11 @@ class IfcStore:
    path = ""
    file = None
    schema = None
+    cache = None
+    cache_path = None
    id_map = {}
    guid_map = {}
+    deleted_ids = set()
    edited_objs = set()
    pset_template_path = ""
    pset_template_file = None
@@ -38,28 +43,36 @@ class IfcStore:
    library_file = None
    element_listeners = set()
    undo_redo_stack_objects = set()
+    undo_redo_stack_object_names = {}
    current_transaction = ""
    last_transaction = ""
    history = []
    future = []
+    schema_identifiers = ["IFC4", "IFC2X3"]

    @staticmethod
    def purge():
        IfcStore.path = ""
        IfcStore.file = None
        IfcStore.schema = None
+        IfcStore.cache = None
+        IfcStore.cache_path = None
        IfcStore.id_map = {}
        IfcStore.guid_map = {}
+        IfcStore.deleted_ids = set()
        IfcStore.edited_objs = set()
        IfcStore.pset_template_path = ""
        IfcStore.pset_template_file = None
        IfcStore.library_path = ""
        IfcStore.library_file = None
+        IfcStore.schema_identifiers = ["IFC4", "IFC2X3"]

    @staticmethod
    def get_file():
        if IfcStore.file is None:
            IfcStore.path = bpy.context.scene.BIMProperties.ifc_file
+            if not os.path.isabs(IfcStore.path):
+                IfcStore.path = os.path.abspath(os.path.join(bpy.path.abspath("//"), IfcStore.path))
            if IfcStore.path:
                try:
                    IfcStore.load_file(IfcStore.path)
@@ -67,6 +80,31 @@ class IfcStore:
                    pass
        return IfcStore.file

+    @staticmethod
+    def get_cache():
+        if IfcStore.cache is None and IfcStore.path:
+            ifc_key = IfcStore.path + IfcStore.file.wrapped_data.header.file_name.time_stamp
+            ifc_hash = hashlib.md5(ifc_key.encode("utf-8")).hexdigest()
+            IfcStore.cache_path = os.path.join(bpy.context.scene.BIMProperties.data_dir, "cache", f"{ifc_hash}.h5")
+            cache_settings = ifcopenshell.geom.settings()
+            cache_settings.set(cache_settings.STRICT_TOLERANCE, True)
+            try:
+                IfcStore.cache = ifcopenshell.geom.serializers.hdf5(IfcStore.cache_path, cache_settings)
+            except:
+                return
+        return IfcStore.cache
+
+    @staticmethod
+    def update_cache():
+        if not IfcStore.cache:
+            return
+        ifc_key = IfcStore.path + IfcStore.file.wrapped_data.header.file_name.time_stamp
+        ifc_hash = hashlib.md5(ifc_key.encode("utf-8")).hexdigest()
+        new_cache_path = os.path.join(bpy.context.scene.BIMProperties.data_dir, "cache", f"{ifc_hash}.h5")
+        IfcStore.cache = None
+        os.replace(IfcStore.cache_path, new_cache_path)
+        IfcStore.get_cache()
+
    @staticmethod
    def load_file(path):
        extension = path.split(".")[-1]
@@ -85,7 +123,9 @@ class IfcStore:
    @staticmethod
    def get_schema():
        if IfcStore.file is None:
-            return
+            IfcStore.schema = ifcopenshell.ifcopenshell_wrapper.schema_by_name(
+                bpy.context.scene.BIMProjectProperties.export_schema
+            )
        elif IfcStore.schema is None:
            IfcStore.schema = ifcopenshell.ifcopenshell_wrapper.schema_by_name(IfcStore.file.schema)
        return IfcStore.schema
@@ -108,14 +148,32 @@ class IfcStore:
        IfcStore.element_listeners.add(callback)

    @staticmethod
-    def update_undo_redo_stack_objects():
+    def track_undo_redo_stack_object_map():
+        """Keeps track of currently mapped object names, typically during undo and redo
+
+        When any Blender object is stored outside a Blender PointerProperty, such as
+        in a regular Python list, there is the likely probability that the object
+        will be invalidated when undo or redo occurs. Object invalidation seems to
+        occur whenever an object is affected during an operation.
+
+        For example, if an operator deletes a modifier on o1, then o1 will be invalidated.
+        """
+        for key, value in IfcStore.id_map.items():
+            try:
+                IfcStore.undo_redo_stack_object_names[key] = value.name
+            except:
+                continue
+
+    @staticmethod
+    def track_undo_redo_stack_selected_objects():
        """Keeps track of selected object names, typically during undo and redo

        When any Blender object is stored outside a Blender PointerProperty, such as
        in a regular Python list, there is the likely probability that the object
        will be invalidated when undo or redo occurs. Object invalidation seems to
-        only occur for selected objects either pre/post undo/redo event, including
-        selected objects for consecutive undo/redos, and all children.
+        occur for selected objects either pre/post undo/redo event, including
+        selected objects for consecutive undo/redos, and all children. This is
+        important because selected objects are often deleted from the scene.

        So if I first select o1, then o2, then o3, then press undo, o3 will be
        invalidated. If instead I press undo twice, o3 and o2 will be invalidated.
@@ -130,14 +188,23 @@ class IfcStore:
        IfcStore.undo_redo_stack_objects |= objects

    @staticmethod
-    def reload_linked_elements(objects=None):
+    def reload_undo_redo_stack_objects():
+        """Reloads any invalidated objects after undo or redo
+
+        After an undo or redo operation, objects may have been invalidated in
+        our id_map and guid_map. Invalidated objects are typically those that
+        have been manipulated or deleted. This checks the cache of mapped and
+        selected objects prior to the operation and ensures that if the object
+        is invalidated, they are reloaded based on the object name that was
+        tracked prior to the undo / redo.
+        """
        file = IfcStore.get_file()
        if not file:
            return
-        if objects is None:
-            objects = bpy.data.objects

-        for obj in objects:
+        # First, reload objects that were selected or active
+        for name in IfcStore.undo_redo_stack_objects:
+            obj = bpy.data.objects.get(name)
            if not obj:
                continue
            if not obj.BIMObjectProperties.ifc_definition_id:
@@ -148,6 +215,55 @@ class IfcStore:
                data["guid"] = element.GlobalId
            IfcStore.commit_link_element(data)

+        # Scan for any straggling invalidated objects which were indirectly affected and reload them too.
+        for key, value in IfcStore.id_map.items():
+            try:
+                value.name
+            except:
+                obj = bpy.data.objects.get(IfcStore.undo_redo_stack_object_names[key])
+                if not obj or not obj.BIMObjectProperties.ifc_definition_id:
+                    continue
+                element = file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+                data = {"id": element.id(), "obj": obj.name}
+                if hasattr(element, "GlobalId"):
+                    data["guid"] = element.GlobalId
+                IfcStore.commit_link_element(data)
+
+
+    @staticmethod
+    def relink_all_objects():
+        file = IfcStore.get_file()
+        if not file:
+            return
+        for obj in bpy.data.objects:
+            if not obj:
+                continue
+            if not obj.BIMObjectProperties.ifc_definition_id:
+                continue
+            element = file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+            data = {"id": element.id(), "obj": obj.name}
+            if hasattr(element, "GlobalId"):
+                data["guid"] = element.GlobalId
+            IfcStore.commit_link_element(data)
+
+
+    @staticmethod
+    def delete_element(element):
+        IfcStore.deleted_ids.add(element.id())
+        if IfcStore.history:
+            data = {"id": element.id()}
+            IfcStore.history[-1]["operations"].append(
+                {"rollback": IfcStore.rollback_delete_element, "commit": IfcStore.commit_delete_element, "data": data}
+            )
+
+    @staticmethod
+    def rollback_delete_element(data):
+        IfcStore.deleted_ids.remove(data["id"])
+
+    @staticmethod
+    def commit_delete_element(data):
+        IfcStore.deleted_ids.add(data["id"])
+
    @staticmethod
    def link_element(element, obj):
        IfcStore.id_map[element.id()] = obj
@@ -224,7 +340,9 @@ class IfcStore:
        except:
            pass

-        if obj:
+        if element and element.is_a("IfcSurfaceStyle"):
+            obj.BIMMaterialProperties.ifc_style_id = 0
+        elif obj:
            obj.BIMObjectProperties.ifc_definition_id = 0

    @staticmethod
@@ -232,7 +350,6 @@ class IfcStore:
        is_top_level_operator = not bool(IfcStore.current_transaction)

        if is_top_level_operator:
-            active_object = context.active_object
            IfcStore.begin_transaction(operator)
            IfcStore.get_file().begin_transaction()
            # This empty transaction ensures that each operator has at least one transaction
@@ -248,17 +365,14 @@ class IfcStore:
                operator, rollback=lambda d: IfcStore.get_file().undo(), commit=lambda d: IfcStore.get_file().redo()
            )
            IfcStore.end_transaction(operator)
-            try:
-                active_object.name
-                context.view_layer.objects.active = active_object
-            except:
-                pass
+            blenderbim.bim.handler.refresh_ui_data()

        return result

    @staticmethod
    def begin_transaction(operator):
        IfcStore.undo_redo_stack_objects = set()
+        IfcStore.undo_redo_stack_object_names = {}
        IfcStore.current_transaction = str(uuid.uuid4())
        operator.transaction_key = IfcStore.current_transaction

@@ -16,11 +16,13 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

+import os
 import re
 import bpy
 import time
 import bmesh
 import shutil
+import logging
 import threading
 import mathutils
 import numpy as np
@@ -31,6 +33,8 @@ import ifcopenshell.util.unit
 import ifcopenshell.util.element
 import ifcopenshell.util.selector
 import ifcopenshell.util.geolocation
+import blenderbim.tool as tool
+from itertools import chain, accumulate
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.module.drawing.prop import get_diagram_scales

@@ -67,6 +71,7 @@ class MaterialCreator:
        self.add_default_material(element)
        if self.parse_representations(element):
            self.assign_material_slots_to_faces()
+        tool.Geometry.record_object_materials(obj)

    def add_default_material(self, element):
        element_material = ifcopenshell.util.element.get_material(element)
@@ -107,7 +112,7 @@ class MaterialCreator:

    def parse_representation(self, representation):
        has_parsed = False
-        representation_items = self.resolve_mapped_representation_items(representation)
+        representation_items = self.resolve_all_representation_items(representation)
        for item in representation_items:
            if self.parse_representation_item(item):
                has_parsed = True
@@ -141,13 +146,12 @@ class MaterialCreator:
            ]
            self.mesh.polygons.foreach_set("material_index", material_index)

-    def resolve_mapped_representation_items(self, representation):
+    def resolve_all_representation_items(self, representation):
        items = []
        for item in representation.Items:
            if item.is_a("IfcMappedItem"):
                items.extend(item.MappingSource.MappedRepresentation.Items)
-            else:
-                items.append(item)
+            items.append(item)
        return items


@@ -159,6 +163,7 @@ class IfcImporter:
        self.settings = ifcopenshell.geom.settings()
        self.settings.set_deflection_tolerance(self.ifc_import_settings.deflection_tolerance)
        self.settings.set_angular_tolerance(self.ifc_import_settings.angular_tolerance)
+        self.settings.set(self.settings.STRICT_TOLERANCE, True)
        self.settings_native = ifcopenshell.geom.settings()
        self.settings_native.set(self.settings_native.INCLUDE_CURVES, True)
        self.settings_2d = ifcopenshell.geom.settings()
@@ -217,7 +222,7 @@ class IfcImporter:
        self.profile_code("Create materials")
        self.create_styles()
        self.profile_code("Create styles")
-        self.create_annotation()
+        self.create_annotations()
        self.profile_code("Create annotation")
        self.parse_native_elements()
        self.profile_code("Parsing native elements")
@@ -278,10 +283,22 @@ class IfcImporter:
            for c in self.file.by_type("IfcGeometricRepresentationSubContext")
            if c.ContextIdentifier in ["Body", "Facetation"]
        ]
+        # Ideally, all representations should be in a subcontext, but some BIM programs don't do this correctly
+        self.body_contexts.extend(
+            [
+                c.id()
+                for c in self.file.by_type("IfcGeometricRepresentationContext", include_subtypes=False)
+                if c.ContextType == "Model"
+            ]
+        )
        if self.body_contexts:
            self.settings.set_context_ids(self.body_contexts)
+        # Annotation is to accommodate broken Revit files
+        # See https://github.com/Autodesk/revit-ifc/issues/187
        self.plan_contexts = [
-            c.id() for c in self.file.by_type("IfcGeometricRepresentationContext") if c.ContextType == "Plan"
+            c.id()
+            for c in self.file.by_type("IfcGeometricRepresentationContext")
+            if c.ContextType in ["Plan", "Annotation"]
        ]
        if self.plan_contexts:
            self.settings_2d.set_context_ids(self.plan_contexts)
@@ -289,8 +306,11 @@ class IfcImporter:
    def process_element_filter(self):
        if self.ifc_import_settings.has_filter:
            self.elements = set(self.ifc_import_settings.elements)
+            # TODO: enable filtering for annotations
+            self.annotations = set(self.file.by_type("IfcAnnotation"))
        else:
            self.elements = set(self.file.by_type("IfcElement"))
+            self.annotations = set(self.file.by_type("IfcAnnotation"))

        if self.ifc_import_settings.has_filter and self.ifc_import_settings.should_filter_spatial_elements:
            self.spatial_elements = self.get_spatial_elements_filtered_by_elements(self.elements)
@@ -337,16 +357,17 @@ class IfcImporter:
        # FacetedBreps (without voids) are meshes. See #841.
        # Commented out as seems currently too slow.
        # if self.is_native_faceted_brep(representations):
-        #     self.native_data[element.GlobalId] = {
-        #         "representations": representations,
-        #         "representation": self.get_body_representation(element.Representation.Representations),
-        #         "type": "IfcFacetedBrep",
-        #     }
-        #     return True
+        #    self.native_data[element.GlobalId] = {
+        #        "representations": representations,
+        #        "representation": self.get_body_representation(element.Representation.Representations),
+        #        "type": "IfcFacetedBrep",
+        #    }
+        #    return True

    def is_native_swept_disk_solid(self, representations):
        for representation in representations:
-            if len(representation["raw"].Items) == 1 and representation["raw"].Items[0].is_a("IfcSweptDiskSolid"):
+            items = representation["raw"].Items or []  # Be forgiving of invalid IFCs because Revit :(
+            if len(items) == 1 and items[0].is_a("IfcSweptDiskSolid"):
                return True
        return False

@@ -443,7 +464,9 @@ class IfcImporter:
    def apply_blender_offset_to_matrix_world(self, obj, matrix):
        props = bpy.context.scene.BIMGeoreferenceProperties
        if props.has_blender_offset:
-            if self.is_point_far_away((matrix[0, 3], matrix[1, 3], matrix[2, 3])):
+            if obj.data and obj.data.get("has_cartesian_point_offset", None):
+                obj.BIMObjectProperties.blender_offset_type = "CARTESIAN_POINT"
+            elif self.is_point_far_away((matrix[0, 3], matrix[1, 3], matrix[2, 3])):
                obj.BIMObjectProperties.blender_offset_type = "OBJECT_PLACEMENT"
                matrix = ifcopenshell.util.geolocation.global2local(
                    matrix,
@@ -453,8 +476,6 @@ class IfcImporter:
                    float(props.blender_x_axis_abscissa),
                    float(props.blender_x_axis_ordinate),
                )
-            else:
-                obj.BIMObjectProperties.blender_offset_type = "CARTESIAN_POINT"

        if self.ifc_import_settings.should_offset_model:
            matrix[0, 3] += self.ifc_import_settings.model_offset_coordinates[0]
@@ -502,7 +523,7 @@ class IfcImporter:
            mesh = self.create_mesh(axis, shape)
            obj = bpy.data.objects.new(f"IfcGridAxis/{axis.AxisTag}", mesh)
            self.link_element(axis, obj)
-            obj.matrix_world = grid_obj.matrix_world
+            self.set_matrix_world(obj, grid_obj.matrix_world)
            grid_collection.objects.link(obj)

    def create_type_products(self):
@@ -553,7 +574,6 @@ class IfcImporter:
    def create_native_elements(self):
        total = 0
        checkpoint = time.time()
-        bm = bmesh.new()
        for element in self.native_elements:
            total += 1
            if total % 250 == 0:
@@ -575,19 +595,14 @@ class IfcImporter:
                mesh.name = mesh_name
                self.meshes[mesh_name] = mesh
            self.create_product(element, mesh=mesh)
-            if native_data["type"] == "IfcFacetedBrep":
-                # The current implementation doesn't reuse vertices, so we weld it after assigning materials.
-                # This welding isn't true to the representation, but is easy and seems inexpensive.
-                bm.from_mesh(mesh)
-                bmesh.ops.remove_doubles(bm, verts=bm.verts, dist=0.001)
-                bm.to_mesh(mesh)
-                bm.clear()
-        bm.free()
        print("Done creating geometry")

    def create_spatial_elements(self):
        self.create_generic_elements(self.spatial_elements)

+    def create_annotations(self):
+        self.create_generic_elements(self.annotations)
+
    def create_elements(self):
        self.create_generic_elements(self.elements)

@@ -615,6 +630,9 @@ class IfcImporter:
            )
        else:
            iterator = ifcopenshell.geom.iterator(self.settings, self.file, include=products)
+        cache = IfcStore.get_cache()
+        if cache:
+            iterator.set_cache(cache)
        valid_file = iterator.initialize()
        if not valid_file:
            return results
@@ -631,7 +649,7 @@ class IfcImporter:
                    )
                )
                checkpoint = time.time()
-                # self.update_progress(((total / approx_total_products) * progress_range) + start_progress)
+                self.update_progress((iterator.progress() / 100 * progress_range) + start_progress)
            shape = iterator.get()
            if shape:
                product = self.file.by_id(shape.guid)
@@ -650,9 +668,6 @@ class IfcImporter:
        print("Done creating geometry")
        return results

-    def create_annotation(self):
-        self.create_curve_products(self.file.by_type("IfcAnnotation"))
-
    def create_structural_items(self):
        # Create structural collections
        self.structural_member_collection = bpy.data.collections.new("Members")
@@ -690,7 +705,7 @@ class IfcImporter:
            mesh.from_pydata([mathutils.Vector(vertex) * self.unit_scale], [], [])

            obj = bpy.data.objects.new("{}/{}".format(product.is_a(), product.Name), mesh)
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, placement_matrix)
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, placement_matrix))
            self.link_element(product, obj)

    def get_pointcloud_representation(self, product):
@@ -749,7 +764,7 @@ class IfcImporter:
        mesh.from_pydata(vertex_list, [], [])

        obj = bpy.data.objects.new("{}/{}".format(product.is_a(), product.Name), mesh)
-        obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, placement_matrix)
+        self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, placement_matrix))
        self.link_element(product, obj)
        return product

@@ -763,6 +778,9 @@ class IfcImporter:
            )
        else:
            iterator = ifcopenshell.geom.iterator(self.settings_2d, self.file, include=products)
+        cache = IfcStore.get_cache()
+        if cache:
+            iterator.set_cache(cache)
        valid_file = iterator.initialize()
        if not valid_file:
            return results
@@ -793,6 +811,10 @@ class IfcImporter:
            pass
        elif element.is_a("IfcAnnotation") and element.ObjectType == "DRAWING":
            mesh = self.create_camera(element, shape)
+            self.link_mesh(shape, mesh)
+        elif element.is_a("IfcAnnotation") and self.is_curve_annotation(element):
+            mesh = self.create_curve(element, shape)
+            self.link_mesh(shape, mesh)
        elif shape:
            mesh_name = self.get_mesh_name(shape.geometry)
            mesh = self.meshes.get(mesh_name)
@@ -812,13 +834,13 @@ class IfcImporter:
            mat = np.array(
                ([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1])
            )
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, mat)
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, mat))
            self.material_creator.create(element, obj, mesh)
        elif mesh:
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element))
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element)))
            self.material_creator.create(element, obj, mesh)
        elif hasattr(element, "ObjectPlacement"):
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element))
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element)))

        self.add_opening_relation(element, obj)

@@ -834,79 +856,167 @@ class IfcImporter:

    def create_native_faceted_brep(self, element, mesh_name):
        # TODO: georeferencing?
-        # Note: to make this algorithm simpler (it's already confusing) we don't reuse / weld verts
        # co [x y z x y z x y z ...]
        # vertex_index [i i i i i ...]
        # loop_start [0 3 6 9 ...] (for tris)
        # loop_total [3 3 3 3 ...] (for tris)
-        co = []
-        vertex_index = []
-        loop_start = []
-        loop_total = []
-        total_verts = 0
-        total_polygons = 0
-        materials = []
-        material_ids = []
-        item_index = 0
+        self.mesh_data = {
+            "co": [],
+            "vertex_index": [],
+            "loop_start": [],
+            "loop_total": [],
+            "total_verts": 0,
+            "total_polygons": 0,
+            "materials": [],
+            "material_ids": [],
+        }
+
+        for representation in element.Representation.Representations:
+            if representation.ContextOfItems.id() not in self.body_contexts:
+                continue
+            self.convert_representation(representation)
+
+        mesh = bpy.data.meshes.new("Native")
+        mesh.vertices.add(self.mesh_data["total_verts"])
+        mesh.vertices.foreach_set("co", [c * self.unit_scale for c in self.mesh_data["co"]])
+        # mesh.vertices.foreach_set("co", self.mesh_data["co"])
+        mesh.loops.add(len(self.mesh_data["vertex_index"]))
+        mesh.loops.foreach_set("vertex_index", self.mesh_data["vertex_index"])
+        mesh.polygons.add(self.mesh_data["total_polygons"])
+        mesh.polygons.foreach_set("loop_start", self.mesh_data["loop_start"])
+        mesh.polygons.foreach_set("loop_total", self.mesh_data["loop_total"])
+        mesh.update()
+
+        mesh["ios_materials"] = self.mesh_data["materials"]
+        mesh["ios_material_ids"] = self.mesh_data["material_ids"]
+        return mesh
+
+    def convert_representation(self, representation):
+        for item in representation.Items:
+            self.convert_representation_item(item)
+
+    def convert_representation_item(self, item):
+        if item.is_a("IfcMappedItem"):
+            # mapping_target = matrix
+            self.convert_representation(item.MappingSource.MappedRepresentation)
+        elif item.is_a() == "IfcFacetedBrep":
+            self.convert_representation_item_faceted_brep(item)
+
+    def convert_representation_item_faceted_brep(self, item):
+        # On a few occasions, we flatten a list. This seems to be the most efficient way to do it.
+        # https://stackoverflow.com/questions/20112776/how-do-i-flatten-a-list-of-lists-nested-lists
+        mesh = item.get_info_2(recursive=True)
+
+        # For huge face sets it might be better to do a "flatmap" instead of sum()
+        # bounds = sum((f["Bounds"] for f in mesh["Outer"]["CfsFaces"] if len(f["Bounds"]) == 1), ())
+        bounds = tuple(chain.from_iterable(f["Bounds"] for f in mesh["Outer"]["CfsFaces"] if len(f["Bounds"]) == 1))
+        # Here are some untested alternatives, are they faster?
+        # bounds = tuple((f["Bounds"] for f in mesh["Outer"]["CfsFaces"] if len(f["Bounds"]) == 1))[0]
+        # bounds = chain.from_iterable(f["Bounds"] for f in mesh["Outer"]["CfsFaces"] if len(f["Bounds"]) == 1)
+
+        polygons = [[(p["id"], p["Coordinates"]) for p in b["Bound"]["Polygon"]] for b in bounds]
+
+        for face in mesh["Outer"]["CfsFaces"]:
+            # Blender cannot handle faces with holes.
+            if len(face["Bounds"]) > 1:
+                inner_bounds = []
+                inner_bound_point_ids = []
+                for bound in face["Bounds"]:
+                    if bound["type"] == "IfcFaceOuterBound":
+                        outer_bound = [[p["Coordinates"] for p in bound["Bound"]["Polygon"]]]
+                        outer_bound_point_ids = [[p["id"] for p in bound["Bound"]["Polygon"]]]
+                    else:
+                        inner_bounds.append([p["Coordinates"] for p in bound["Bound"]["Polygon"]])
+                        inner_bound_point_ids.append([p["id"] for p in bound["Bound"]["Polygon"]])
+                points = outer_bound[0].copy()
+                [points.extend(p) for p in inner_bounds]
+                point_ids = outer_bound_point_ids[0].copy()
+                [point_ids.extend(p) for p in inner_bound_point_ids]
+
+                tessellated_polygons = mathutils.geometry.tessellate_polygon(outer_bound + inner_bounds)
+                polygons.extend([[(point_ids[pi], points[pi]) for pi in t] for t in tessellated_polygons])
+
+        # Clever vertex welding algorithm by Thomas Krijnen. See #841.
+
+        # by id
+        di0 = {}
+        # by coords
+        di1 = {}
+
+        vertex_index_offset = self.mesh_data["total_verts"]
+
+        def lookup(id_coords):
+            idx = di0.get(id_coords[0])
+            if idx is None:
+                idx = di1.get(id_coords[1])
+                if idx is None:
+                    l = len(di0)
+                    di0[id_coords[0]] = l
+                    di1[id_coords[1]] = l
+                    return l + vertex_index_offset
+                else:
+                    return idx + vertex_index_offset
+            else:
+                return idx + vertex_index_offset
+
+        mapped_polygons = [list(map(lookup, p)) for p in polygons]
+
+        self.mesh_data["vertex_index"].extend(chain.from_iterable(mapped_polygons))
+
+        # Flattened vertex coords
+        self.mesh_data["co"].extend(chain.from_iterable(di1.keys()))
+        self.mesh_data["total_verts"] += len(di1.keys())
+        loop_total = [len(p) for p in mapped_polygons]
+        total_polygons = len(mapped_polygons)
+        self.mesh_data["total_polygons"] += total_polygons
+
+        self.mesh_data["materials"].append(self.get_representation_item_material_name(item) or "NULLMAT")
+        material_index = len(self.mesh_data["materials"]) - 1
+        if self.mesh_data["materials"][material_index] == "NULLMAT":
+            # Magic number -1 represents no material, until this has a better approach
+            self.mesh_data["material_ids"] += [-1] * total_polygons
+        else:
+            self.mesh_data["material_ids"] += [material_index] * total_polygons
+
+        if self.mesh_data["loop_start"]:
+            loop_start_offset = self.mesh_data["loop_start"][-1] + self.mesh_data["loop_total"][-1]
+        else:
+            loop_start_offset = 0
+
+        loop_start = [loop_start_offset] + [loop_start_offset + i for i in list(accumulate(loop_total[0:-1]))]
+        self.mesh_data["loop_total"].extend(loop_total)
+        self.mesh_data["loop_start"].extend(loop_start)
+        # list(di1.keys())
+
+    def create_native_swept_disk_solid(self, element, mesh_name):
+        # TODO: georeferencing?
+        curve = bpy.data.curves.new(mesh_name, type="CURVE")
+        curve.dimensions = "3D"
+        curve.resolution_u = 2
+        polyline = curve.splines.new("POLY")

        for representation in self.native_data[element.GlobalId]["representations"]:
            for item in representation["raw"].Items:
-                # TODO: if I reimplement native faceted breps, recheck this material implementation
-                materials.append(self.get_representation_item_material_name(item) or "NULLMAT")
-                mesh = item.get_info_2(recursive=True)  # See bug #841
-                total_item_polygons = 0
-                for face in mesh["Outer"]["CfsFaces"]:
-                    # Blender cannot handle faces with holes.
-                    if len(face["Bounds"]) > 1:
-                        inner_bounds = []
-                        for bound in face["Bounds"]:
-                            if bound["type"] == "IfcFaceOuterBound":
-                                outer_bound = [[p["Coordinates"] for p in bound["Bound"]["Polygon"]]]
-                            else:
-                                inner_bounds.append([p["Coordinates"] for p in bound["Bound"]["Polygon"]])
-                        points = outer_bound[0].copy()
-                        [points.extend(p) for p in inner_bounds]
-                        tessellated_polygons = mathutils.geometry.tessellate_polygon(outer_bound + inner_bounds)
-                        tessellated_faces = [({"Coordinates": points[pi]} for pi in t) for t in tessellated_polygons]
-                    else:
-                        tessellated_faces = [face["Bounds"][0]["Bound"]["Polygon"]]
+                # TODO: support inner radius, start param, and end param
+                geometry = ifcopenshell.geom.create_shape(self.settings_native, item.Directrix)
+                e = geometry.edges
+                v = geometry.verts
+                vertices = [[v[i], v[i + 1], v[i + 2], 1] for i in range(0, len(v), 3)]
+                edges = [[e[i], e[i + 1]] for i in range(0, len(e), 2)]
+                v2 = None
+                for edge in edges:
+                    v1 = vertices[edge[0]]
+                    if v1 != v2:
+                        polyline = curve.splines.new("POLY")
+                        polyline.points[-1].co = representation["matrix"] @ mathutils.Vector(v1)
+                    v2 = vertices[edge[1]]
+                    polyline.points.add(1)
+                    polyline.points[-1].co = representation["matrix"] @ mathutils.Vector(v2)

-                    for tessellated_face in tessellated_faces:
-                        loop_start.append(total_verts)
-                        loop_count = 0
-                        total_polygons += 1
-                        total_item_polygons += 1
-                        for point in tessellated_face:
-                            co.extend(
-                                representation["matrix"]
-                                @ mathutils.Vector((c * self.unit_scale for c in point["Coordinates"]))
-                            )
-                            total_verts += 1
-                            loop_count += 1
-                        loop_total.append(loop_count)
-                vertex_index = range(0, total_verts)
-                if materials[item_index] == "NULLMAT":
-                    # Magic number -1 represents no material, until this has a better approach
-                    material_ids += [-1] * total_item_polygons
-                else:
-                    material_ids += [item_index] * total_item_polygons
-                item_index += 1
-        mesh = bpy.data.meshes.new("Tester")
+        curve.bevel_depth = self.unit_scale * item.Radius
+        return curve

-        mesh.vertices.add(total_verts)
-        mesh.vertices.foreach_set("co", co)
-        mesh.loops.add(total_verts)
-        mesh.loops.foreach_set("vertex_index", vertex_index)
-        mesh.polygons.add(total_polygons)
-        mesh.polygons.foreach_set("loop_start", loop_start)
-        mesh.polygons.foreach_set("loop_total", loop_total)
-        mesh.update()
-
-        mesh["ios_materials"] = materials
-        mesh["ios_material_ids"] = material_ids
-        return mesh
-
-    def create_native_swept_disk_solid(self, element, mesh_name):
+    def create_native_annotation(self, element, mesh_name):
        # TODO: georeferencing?
        curve = bpy.data.curves.new(mesh_name, type="CURVE")
        curve.dimensions = "3D"
@@ -1082,6 +1192,7 @@ class IfcImporter:
    def create_spatial_decomposition_collections(self):
        for rel_aggregate in self.project["ifc"].IsDecomposedBy or []:
            self.create_spatial_decomposition_collection(self.project["blender"], rel_aggregate.RelatedObjects)
+        self.create_views_collection()
        self.create_type_collection()

    def create_type_collection(self):
@@ -1093,6 +1204,22 @@ class IfcImporter:
            self.type_collection = bpy.data.collections.new("Types")
            self.project["blender"].children.link(self.type_collection)

+    def create_views_collection(self):
+        view_collection = None
+        for collection in self.project["blender"].children:
+            if collection.name == "Views":
+                view_collection = collection
+                break
+        if not view_collection:
+            view_collection = bpy.data.collections.new("Views")
+            self.project["blender"].children.link(view_collection)
+        for element in self.file.by_type("IfcAnnotation"):
+            if element.ObjectType == "DRAWING":
+                group = [r for r in element.HasAssignments if r.is_a("IfcRelAssignsToGroup")][0].RelatingGroup
+                collection = bpy.data.collections.new("IfcGroup/" + group.Name)
+                self.collections[group.GlobalId] = collection
+                view_collection.children.link(collection)
+
    def create_spatial_decomposition_collection(self, parent, related_objects):
        for element in related_objects:
            if element not in self.spatial_elements:
@@ -1171,25 +1298,172 @@ class IfcImporter:
            name = style.Name or str(style.id())
            blender_material = bpy.data.materials.new(name)

-        old_definition_id = blender_material.BIMObjectProperties.ifc_definition_id
-        if not old_definition_id:
-            self.link_element(style, blender_material)
-        blender_material.BIMObjectProperties.ifc_definition_id = old_definition_id
+        self.link_element(style, blender_material)

        blender_material.BIMMaterialProperties.ifc_style_id = style.id()
        self.material_creator.styles[style.id()] = blender_material
+
+        rendering_style = None
+        texture_style = None
+
        for surface_style in style.Styles:
-            if surface_style.is_a("IfcSurfaceStyleShading"):
-                alpha = 1.0
-                # Transparency was added in IFC4
-                if hasattr(surface_style, "Transparency") and surface_style.Transparency:
-                    alpha = 1 - surface_style.Transparency
-                blender_material.diffuse_color = (
-                    surface_style.SurfaceColour.Red,
-                    surface_style.SurfaceColour.Green,
-                    surface_style.SurfaceColour.Blue,
-                    alpha,
+            if surface_style.is_a() == "IfcSurfaceStyleShading":
+                self.create_surface_style_shading(blender_material, surface_style)
+            elif surface_style.is_a("IfcSurfaceStyleRendering"):
+                rendering_style = surface_style
+                self.create_surface_style_rendering(blender_material, surface_style)
+            elif surface_style.is_a("IfcSurfaceStyleWithTextures"):
+                texture_style = surface_style
+
+        if rendering_style and texture_style:
+            self.create_surface_style_with_textures(blender_material, rendering_style, texture_style)
+
+    def create_surface_style_shading(self, blender_material, surface_style):
+        alpha = 1.0
+        # Transparency was added in IFC4
+        if hasattr(surface_style, "Transparency") and surface_style.Transparency:
+            alpha = 1 - surface_style.Transparency
+        blender_material.diffuse_color = (
+            surface_style.SurfaceColour.Red,
+            surface_style.SurfaceColour.Green,
+            surface_style.SurfaceColour.Blue,
+            alpha,
+        )
+
+    def create_surface_style_rendering(self, blender_material, surface_style):
+        self.create_surface_style_shading(blender_material, surface_style)
+        if surface_style.ReflectanceMethod in ["PHYSICAL", "NOTDEFINED"]:
+            blender_material.use_nodes = True
+            bsdf = blender_material.node_tree.nodes["Principled BSDF"]
+            if surface_style.DiffuseColour and surface_style.DiffuseColour.is_a("IfcColourRgb"):
+                bsdf.inputs["Base Color"].default_value = (
+                    surface_style.DiffuseColour.Red,
+                    surface_style.DiffuseColour.Green,
+                    surface_style.DiffuseColour.Blue,
+                    1,
                )
+            if surface_style.SpecularColour and surface_style.SpecularColour.is_a("IfcNormalisedRatioMeasure"):
+                bsdf.inputs["Metallic"].default_value = surface_style.SpecularColour.wrappedValue
+            if surface_style.SpecularHighlight and surface_style.SpecularHighlight.is_a("IfcSpecularRoughness"):
+                bsdf.inputs["Roughness"].default_value = surface_style.SpecularHighlight.wrappedValue
+            if hasattr(surface_style, "Transparency") and surface_style.Transparency:
+                bsdf.inputs["Alpha"].default_value = 1 - surface_style.Transparency
+                blender_material.blend_method = "BLEND"
+        elif surface_style.ReflectanceMethod == "FLAT":
+            blender_material.use_nodes = True
+
+            output = {n.type: n for n in blender_material.node_tree.nodes}.get("OUTPUT_MATERIAL", None)
+            bsdf = blender_material.node_tree.nodes["Principled BSDF"]
+
+            mix = blender_material.node_tree.nodes.new(type="ShaderNodeMixShader")
+            mix.location = bsdf.location
+            blender_material.node_tree.links.new(mix.outputs[0], output.inputs["Surface"])
+
+            blender_material.node_tree.nodes.remove(bsdf)
+
+            lightpath = blender_material.node_tree.nodes.new(type="ShaderNodeLightPath")
+            lightpath.location = mix.location - mathutils.Vector((200, -200))
+            blender_material.node_tree.links.new(lightpath.outputs[0], mix.inputs[0])
+
+            bsdf = blender_material.node_tree.nodes.new(type="ShaderNodeBsdfTransparent")
+            bsdf.location = mix.location - mathutils.Vector((200, 0))
+            blender_material.node_tree.links.new(bsdf.outputs[0], mix.inputs[1])
+
+            rgb = blender_material.node_tree.nodes.new(type="ShaderNodeRGB")
+            rgb.location = mix.location - mathutils.Vector((200, 200))
+            blender_material.node_tree.links.new(rgb.outputs[0], mix.inputs[2])
+
+            if surface_style.DiffuseColour and surface_style.DiffuseColour.is_a("IfcColourRgb"):
+                rgb.outputs[0].default_value = (
+                    surface_style.DiffuseColour.Red,
+                    surface_style.DiffuseColour.Green,
+                    surface_style.DiffuseColour.Blue,
+                    1,
+                )
+
+    def create_surface_style_with_textures(self, blender_material, rendering_style, texture_style):
+        for texture in texture_style.Textures:
+            mode = getattr(texture, "Mode", None)
+            node = None
+
+            if texture.is_a("IfcImageTexture"):
+                image_url = texture.URLReference
+                if not os.path.abspath(texture.URLReference) and tool.Ifc.get_path():
+                    image_url = os.path.join(os.path.dirname(tool.Ifc.get_path()), texture.URLReference)
+
+            if rendering_style.ReflectanceMethod in ["PHYSICAL", "NOTDEFINED"]:
+                bsdf = blender_material.node_tree.nodes["Principled BSDF"]
+                if mode == "NORMAL":
+                    normalmap = blender_material.node_tree.nodes.new(type="ShaderNodeNormalMap")
+                    normalmap.location = bsdf.location - mathutils.Vector((200, 0))
+                    blender_material.node_tree.links.new(normalmap.outputs[0], bsdf.inputs["Normal"])
+
+                    node = blender_material.node_tree.nodes.new(type="ShaderNodeTexImage")
+                    node.location = normalmap.location - mathutils.Vector((200, 0))
+                    image = bpy.data.images.load(image_url)
+                    image.colorspace_settings.name = "Non-Color"
+                    node.image = image
+                    blender_material.node_tree.links.new(node.outputs[0], normalmap.inputs["Color"])
+                elif mode == "EMISSIVE":
+                    output = {n.type: n for n in blender_material.node_tree.nodes}.get("OUTPUT_MATERIAL", None)
+
+                    add = blender_material.node_tree.nodes.new(type="ShaderNodeAddShader")
+                    add.location = bsdf.location + mathutils.Vector((200, 0))
+                    blender_material.node_tree.links.new(bsdf.outputs[0], add.inputs[1])
+                    blender_material.node_tree.links.new(add.outputs[0], output.inputs[0])
+
+                    emission = blender_material.node_tree.nodes.new(type="ShaderNodeEmission")
+                    emission.location = add.location - mathutils.Vector((200, 0))
+                    blender_material.node_tree.links.new(emission.outputs[0], add.inputs[0])
+
+                    node = blender_material.node_tree.nodes.new(type="ShaderNodeTexImage")
+                    node.location = emission.location - mathutils.Vector((200, 0))
+                    image = bpy.data.images.load(image_url)
+                    node.image = image
+                    blender_material.node_tree.links.new(node.outputs[0], emission.inputs[0])
+                elif mode == "METALLICROUGHNESS":
+                    separate = blender_material.node_tree.nodes.new(type="ShaderNodeSeparateRGB")
+                    separate.location = bsdf.location - mathutils.Vector((200, 0))
+                    blender_material.node_tree.links.new(separate.outputs[1], bsdf.inputs["Roughness"])
+                    blender_material.node_tree.links.new(separate.outputs[2], bsdf.inputs["Metallic"])
+
+                    node = blender_material.node_tree.nodes.new(type="ShaderNodeTexImage")
+                    node.location = separate.location - mathutils.Vector((200, 0))
+                    image = bpy.data.images.load(image_url)
+                    image.colorspace_settings.name = "Non-Color"
+                    node.image = image
+                    blender_material.node_tree.links.new(node.outputs[0], separate.inputs[0])
+                elif mode == "OCCLUSION":
+                    # TODO work out how to implement glTF settings here
+                    # https://docs.blender.org/manual/en/dev/addons/import_export/scene_gltf2.html
+                    pass
+                elif mode == "DIFFUSE":
+                    node = blender_material.node_tree.nodes.new(type="ShaderNodeTexImage")
+                    node.location = bsdf.location - mathutils.Vector((400, 0))
+                    image = bpy.data.images.load(image_url)
+                    node.image = image
+                    blender_material.node_tree.links.new(node.outputs[0], bsdf.inputs["Base Color"])
+                    blender_material.node_tree.links.new(node.outputs[1], bsdf.inputs["Alpha"])
+                    blender_material.blend_method = "BLEND"
+            elif rendering_style.ReflectanceMethod == "FLAT":
+                bsdf = blender_material.node_tree.nodes["Mix Shader"]
+                if mode == "EMISSIVE":
+                    node = blender_material.node_tree.nodes.new(type="ShaderNodeTexImage")
+                    node.location = bsdf.location - mathutils.Vector((200, 0))
+                    image = bpy.data.images.load(image_url)
+                    node.image = image
+                    blender_material.node_tree.links.new(node.outputs[0], bsdf.inputs[2])
+
+            if node and getattr(texture, "IsMappedBy", None):
+                coordinates = texture.IsMappedBy[0]
+                coord = blender_material.node_tree.nodes.new(type="ShaderNodeTexCoord")
+                coord.location = node.location - mathutils.Vector((200, 0))
+                if coordinates.is_a("IfcTextureCoordinateGenerator") and coordinates.Mode == "COORD":
+                    blender_material.node_tree.links.new(coord.outputs["Generated"], node.inputs["Vector"])
+                elif coordinates.is_a("IfcTextureCoordinateGenerator") and coordinates.Mode == "COORD-EYE":
+                    blender_material.node_tree.links.new(coord.outputs["Camera"], node.inputs["Vector"])
+                else:
+                    blender_material.node_tree.links.new(coord.outputs["UV"], node.inputs["Vector"])

    def get_name(self, element):
        return "{}/{}".format(element.is_a(), element.Name)
@@ -1235,16 +1509,9 @@ class IfcImporter:
            return self.structural_member_collection.objects.link(obj)
        elif element.is_a("IfcStructuralConnection"):
            return self.structural_connection_collection.objects.link(obj)
-        elif element.is_a("IfcAnnotation") and element.ObjectType == "DRAWING":
-            view_collection = bpy.data.collections.get("Views")
-            if not view_collection:
-                view_collection = bpy.data.collections.new("Views")
-                bpy.context.scene.collection.children.link(view_collection)
+        elif element.is_a("IfcAnnotation") and self.is_drawing_annotation(element):
            group = [r for r in element.HasAssignments if r.is_a("IfcRelAssignsToGroup")][0].RelatingGroup
-            drawing_collection = bpy.data.collections.new("IfcGroup/" + group.Name)
-            view_collection.children.link(drawing_collection)
-            drawing_collection.objects.link(obj)
-            return
+            return self.collections[group.GlobalId].objects.link(obj)

        container = ifcopenshell.util.element.get_container(element)
        if container:
@@ -1260,6 +1527,37 @@ class IfcImporter:
            self.ifc_import_settings.logger.warning("Warning: this object is outside the spatial hierarchy %s", element)
            bpy.context.scene.collection.objects.link(obj)

+    def is_curve_annotation(self, element):
+        return element.ObjectType in [
+            "DIMENSION",
+            "EQUAL_DIMENSION",
+            "MISC",
+            "PLAN_LEVEL",
+            "SECTION_LEVEL",
+            "STAIR_ARROW",
+            "TEXT_LEADER",
+        ]
+
+    def is_drawing_annotation(self, element):
+        return element.ObjectType in [
+            "BREAKLINE",
+            "DIMENSION",
+            "DRAWING",
+            "EQUAL_DIMENSION",
+            "GRID",
+            "HIDDEN_LINE",
+            "MISC",
+            "PLAN_LEVEL",
+            "SECTION_LEVEL",
+            "STAIR_ARROW",
+            "TEXT",
+            "TEXT_LEADER",
+            "LEADER",
+            "HATCH",
+            "LINEWORK",
+            "AREA",
+        ]
+
    def get_element_matrix(self, element):
        result = ifcopenshell.util.placement.get_local_placement(element.ObjectPlacement)
        result[0][3] *= self.unit_scale
@@ -1384,8 +1682,39 @@ class IfcImporter:
                else:
                    camera.BIMCameraProperties.diagram_scale = "CUSTOM"
                    camera.BIMCameraProperties.custom_diagram_scale = pset["Scale"]
+            if "HasUnderlay" in pset:
+                camera.BIMCameraProperties.has_underlay = pset["HasUnderlay"]
+            if "HasLinework" in pset:
+                camera.BIMCameraProperties.has_linework = pset["HasLinework"]
+            if "HasAnnotation" in pset:
+                camera.BIMCameraProperties.has_annotation = pset["HasAnnotation"]
        return camera

+    def create_curve(self, element, shape):
+        if hasattr(shape, "geometry"):
+            geometry = shape.geometry
+        else:
+            geometry = shape
+
+        curve = bpy.data.curves.new(self.get_mesh_name(geometry), type="CURVE")
+        curve.dimensions = "3D"
+        curve.resolution_u = 2
+
+        e = geometry.edges
+        v = geometry.verts
+        vertices = [[v[i], v[i + 1], v[i + 2], 1] for i in range(0, len(v), 3)]
+        edges = [[e[i], e[i + 1]] for i in range(0, len(e), 2)]
+        v2 = None
+        for edge in edges:
+            v1 = vertices[edge[0]]
+            if v1 != v2:
+                polyline = curve.splines.new("POLY")
+                polyline.points[-1].co = mathutils.Vector(v1)
+            v2 = vertices[edge[1]]
+            polyline.points.add(1)
+            polyline.points[-1].co = mathutils.Vector(v2)
+        return curve
+
    def create_mesh(self, element, shape):
        try:
            if hasattr(shape, "geometry"):
@@ -1401,20 +1730,22 @@ class IfcImporter:
                and geometry.verts
                and self.is_point_far_away((geometry.verts[0], geometry.verts[1], geometry.verts[2]))
            ):
-                ordinate_index = 0
                verts = [None] * len(geometry.verts)
-                offset_point = (
-                    float(props.blender_eastings) * self.unit_scale,
-                    float(props.blender_northings) * self.unit_scale,
-                    float(props.blender_orthogonal_height) * self.unit_scale,
-                )
-                for i, vert in enumerate(geometry.verts):
-                    if ordinate_index > 2:
-                        ordinate_index = 0
-                    verts[i] = vert - offset_point[ordinate_index]
-                    ordinate_index += 1
+                for i in range(0, len(geometry.verts), 3):
+                    verts[i], verts[i + 1], verts[i + 2] = ifcopenshell.util.geolocation.enh2xyz(
+                        geometry.verts[i],
+                        geometry.verts[i + 1],
+                        geometry.verts[i + 2],
+                        float(props.blender_eastings) * self.unit_scale,
+                        float(props.blender_northings) * self.unit_scale,
+                        float(props.blender_orthogonal_height) * self.unit_scale,
+                        float(props.blender_x_axis_abscissa),
+                        float(props.blender_x_axis_ordinate),
+                    )
+                mesh["has_cartesian_point_offset"] = True
            else:
                verts = geometry.verts
+                mesh["has_cartesian_point_offset"] = False

            if geometry.faces:
                num_vertices = len(verts) // 3
@@ -1502,7 +1833,12 @@ class IfcImporter:
        if "-" in geometry.id:
            mesh.BIMMeshProperties.ifc_definition_id = int(geometry.id.split("-")[0])
        else:
-            mesh.BIMMeshProperties.ifc_definition_id = int(geometry.id)
+            # TODO: See #2002
+            mesh.BIMMeshProperties.ifc_definition_id = int(geometry.id.replace(",", ""))
+
+    def set_matrix_world(self, obj, matrix_world):
+        obj.matrix_world = matrix_world
+        tool.Geometry.record_object_position(obj)


 class IfcImportSettings:
@@ -1525,11 +1861,13 @@ class IfcImportSettings:
        self.collection_mode = "DECOMPOSITION"

    @staticmethod
-    def factory(context, input_file, logger):
-        scene_diff = context.scene.DiffProperties
-        props = context.scene.BIMProjectProperties
+    def factory(context=None, input_file=None, logger=None):
+        scene_diff = bpy.context.scene.DiffProperties
+        props = bpy.context.scene.BIMProjectProperties
        settings = IfcImportSettings()
        settings.input_file = input_file
+        if logger is None:
+            logger = logging.getLogger("ImportIFC")
        settings.logger = logger
        settings.diff_file = scene_diff.diff_json_file
        settings.collection_mode = props.collection_mode
@@ -20,11 +20,14 @@ import bpy
 from . import ui, prop, operator

 classes = (
-    operator.AssignObject,
-    operator.UnassignObject,
-    operator.EnableEditingAggregate,
-    operator.DisableEditingAggregate,
-    operator.AddAggregate,
+    operator.BIM_OT_assign_object,
+    operator.BIM_OT_unassign_object,
+    operator.BIM_OT_enable_editing_aggregate,
+    operator.BIM_OT_disable_editing_aggregate,
+    operator.BIM_OT_add_aggregate,
+    operator.BIM_OT_select_parts,
+    operator.BIM_OT_select_aggregate,
+    operator.BIM_OT_add_part_to_object,
    prop.BIMObjectAggregateProperties,
    ui.BIM_PT_aggregate,
 )
@@ -32,24 +32,50 @@ class AggregateData:
    @classmethod
    def load(cls):
        cls.data = {
-            "has_aggregate": cls.has_aggregate(),
-            "label": cls.get_label(),
+            "has_relating_object": cls.has_relating_object(),
+            "relating_object_label": cls.get_relating_object_label(),
            "relating_object_id": cls.get_relating_object_id(),
+            "has_related_objects": cls.has_related_objects(),
+            "related_objects_amount": cls.get_related_objects_amount(),
+            "ifc_class": cls.ifc_class(),
        }
        cls.is_loaded = True

    @classmethod
-    def has_aggregate(cls):
+    def get_relating_object(cls):
        return ifcopenshell.util.element.get_aggregate(tool.Ifc.get_entity(bpy.context.active_object))

    @classmethod
-    def get_label(cls):
-        aggregate = ifcopenshell.util.element.get_aggregate(tool.Ifc.get_entity(bpy.context.active_object))
+    def has_relating_object(cls) -> bool:
+        return cls.get_relating_object() is not None
+
+    @classmethod
+    def get_relating_object_label(cls) -> str:
+        aggregate = cls.get_relating_object()
        if aggregate:
            return f"{aggregate.is_a()}/{aggregate.Name or ''}"

    @classmethod
-    def get_relating_object_id(cls):
-        aggregate = ifcopenshell.util.element.get_aggregate(tool.Ifc.get_entity(bpy.context.active_object))
+    def get_relating_object_id(cls) -> int:
+        aggregate = cls.get_relating_object()
        if aggregate:
            return aggregate.id()
+
+    @classmethod
+    def get_related_objects(cls):
+        return ifcopenshell.util.element.get_parts(tool.Ifc.get_entity(bpy.context.active_object))
+
+    @classmethod
+    def get_related_objects_amount(cls):
+        parts = cls.get_related_objects()
+        return len(parts) if parts else 0
+
+    @classmethod
+    def has_related_objects(cls) -> bool:
+        return bool(cls.get_related_objects())
+
+    @classmethod
+    def ifc_class(cls) -> str:
+        element = tool.Ifc.get_entity(bpy.context.active_object)
+        if element:
+            return element.is_a()
@@ -17,8 +17,11 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

 import bpy
+import ifcopenshell
+import ifcopenshell.util.element
 import blenderbim.tool as tool
 import blenderbim.core.aggregate as core
+import blenderbim.core.spatial
 import blenderbim.bim.handler
 from blenderbim.bim.ifc import IfcStore

@@ -30,7 +33,9 @@ class Operator:
        return {"FINISHED"}


-class AssignObject(bpy.types.Operator, Operator):
+class BIM_OT_assign_object(bpy.types.Operator, Operator):
+    """Create aggregation relationship between two ifc elements"""
+
    bl_idname = "bim.assign_object"
    bl_label = "Assign Object"
    bl_options = {"REGISTER", "UNDO"}
@@ -47,7 +52,9 @@ class AssignObject(bpy.types.Operator, Operator):
        )


-class UnassignObject(bpy.types.Operator, Operator):
+class BIM_OT_unassign_object(bpy.types.Operator, Operator):
+    """Remove aggregation relationship between two ifc elements"""
+
    bl_idname = "bim.unassign_object"
    bl_label = "Unassign Object"
    bl_options = {"REGISTER", "UNDO"}
@@ -63,7 +70,9 @@ class UnassignObject(bpy.types.Operator, Operator):
        )


-class EnableEditingAggregate(bpy.types.Operator, Operator):
+class BIM_OT_enable_editing_aggregate(bpy.types.Operator, Operator):
+    """Enable editing aggregation relationship"""
+
    bl_idname = "bim.enable_editing_aggregate"
    bl_label = "Enable Editing Aggregate"
    bl_options = {"REGISTER", "UNDO"}
@@ -72,7 +81,9 @@ class EnableEditingAggregate(bpy.types.Operator, Operator):
        core.enable_editing_aggregate(tool.Aggregate, obj=context.active_object)


-class DisableEditingAggregate(bpy.types.Operator, Operator):
+class BIM_OT_disable_editing_aggregate(bpy.types.Operator, Operator):
+    """Disable editing aggregation relationship"""
+
    bl_idname = "bim.disable_editing_aggregate"
    bl_label = "Disable Editing Aggregate"
    bl_options = {"REGISTER", "UNDO"}
@@ -81,7 +92,9 @@ class DisableEditingAggregate(bpy.types.Operator, Operator):
        core.disable_editing_aggregate(tool.Aggregate, obj=context.active_object)


-class AddAggregate(bpy.types.Operator):
+class BIM_OT_add_aggregate(bpy.types.Operator):
+    """Add aggregate to IFC element"""
+
    bl_idname = "bim.add_aggregate"
    bl_label = "Add Aggregate"
    bl_options = {"REGISTER", "UNDO"}
@@ -92,10 +105,99 @@ class AddAggregate(bpy.types.Operator):

    def _execute(self, context):
        obj = bpy.data.objects.get(self.obj) if self.obj else context.active_object
+        element = tool.Ifc.get_entity(obj)
+        if not element:
+            return {"FINISHED"}
+
+        aggregate = self.create_aggregate(context)
+        tool.Collector.sync(obj)
+        current_aggregate = ifcopenshell.util.element.get_aggregate(element)
+        current_container = ifcopenshell.util.element.get_container(element)
+        if current_aggregate:
+            core.assign_object(
+                tool.Ifc,
+                tool.Aggregate,
+                tool.Collector,
+                relating_obj=tool.Ifc.get_object(current_aggregate),
+                related_obj=aggregate,
+            )
+        elif current_container:
+            blenderbim.core.spatial.assign_container(
+                tool.Ifc,
+                tool.Collector,
+                tool.Spatial,
+                structure_obj=tool.Ifc.get_object(current_container),
+                element_obj=aggregate,
+            )
+        core.assign_object(tool.Ifc, tool.Aggregate, tool.Collector, relating_obj=aggregate, related_obj=obj)
+        return {"FINISHED"}
+
+    def create_aggregate(self, context):
        aggregate_collection = bpy.data.collections.new("IfcElementAssembly/Assembly")
        context.scene.collection.children.link(aggregate_collection)
        aggregate = bpy.data.objects.new("Assembly", None)
        aggregate_collection.objects.link(aggregate)
        bpy.ops.bim.assign_class(obj=aggregate.name, ifc_class="IfcElementAssembly")
-        core.assign_object(tool.Ifc, tool.Aggregate, tool.Collector, relating_obj=aggregate, related_obj=obj)
+        return aggregate
+
+
+class BIM_OT_select_parts(bpy.types.Operator):
+    """Select Parts"""
+
+    bl_idname = "bim.select_parts"
+    bl_label = "Select Parts"
+    bl_options = {"REGISTER", "UNDO"}
+    obj: bpy.props.StringProperty()
+
+    def execute(self, context):
+        self.file = IfcStore.get_file()
+        obj = bpy.data.objects.get(self.obj) or context.active_object
+        parts = ifcopenshell.util.element.get_parts(tool.Ifc.get_entity(obj))
+        parts_objs = set(tool.Ifc.get_object(part) for part in parts)
+        selectable_parts_objs = set(context.selectable_objects).intersection(parts_objs)
+        for selectable_part_obj in selectable_parts_objs:
+            selectable_part_obj.select_set(True)
        return {"FINISHED"}
+
+
+class BIM_OT_select_aggregate(bpy.types.Operator):
+    """Select Aggregate"""
+
+    bl_idname = "bim.select_aggregate"
+    bl_label = "Select Aggregate"
+    bl_options = {"REGISTER", "UNDO"}
+    obj: bpy.props.StringProperty()
+
+    def execute(self, context):
+        self.file = IfcStore.get_file()
+        obj = bpy.data.objects.get(self.obj) or context.active_object
+        aggregate = ifcopenshell.util.element.get_aggregate(tool.Ifc.get_entity(obj))
+        aggregate_obj = tool.Ifc.get_object(aggregate)
+        if aggregate_obj in context.selectable_objects:
+            aggregate_obj.select_set(True)
+        return {"FINISHED"}
+
+
+class BIM_OT_add_part_to_object(bpy.types.Operator, Operator):
+    bl_idname = "bim.add_part_to_object"
+    bl_label = "Add Part to Object"
+    bl_options = {"REGISTER", "UNDO"}
+    part_class: bpy.props.StringProperty(name="Class", options={"HIDDEN"})
+    part_name: bpy.props.StringProperty(name="Name")
+    obj: bpy.props.StringProperty(options={"HIDDEN"})
+
+    def invoke(self, context, event):
+        self.part_name = "My " + self.part_class.lstrip("Ifc")
+        return context.window_manager.invoke_props_dialog(self)
+
+    def _execute(self, context):
+        obj = bpy.data.objects.get(self.obj) or context.active_object
+        core.add_part_to_object(
+            tool.Ifc,
+            tool.Aggregate,
+            tool.Collector,
+            tool.Blender,
+            obj=obj,
+            part_class=self.part_class,
+            part_name=self.part_name,
+        )
@@ -32,6 +32,17 @@ from bpy.props import (
 )


+def update_relating_object(self, context):
+    def message(self, context):
+        self.layout.label(text="Please select a valid Ifc Element")
+
+    if self.relating_object is None:
+        return
+    if not self.relating_object.BIMObjectProperties.ifc_definition_id:
+        context.window_manager.popup_menu(message, title="Invalid Element Selected", icon="INFO")
+        self.relating_object = None
+
+
 class BIMObjectAggregateProperties(PropertyGroup):
    is_editing: BoolProperty(name="Is Editing")
-    relating_object: PointerProperty(name="Aggregate", type=bpy.types.Object)
+    relating_object: PointerProperty(name="Aggregate", type=bpy.types.Object, update=update_relating_object)
@@ -28,6 +28,7 @@ class BIM_PT_aggregate(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_object_metadata"

    @classmethod
    def poll(cls, context):
@@ -43,13 +44,14 @@ class BIM_PT_aggregate(Panel):
        return True

    def draw(self, context):
+        layout = self.layout
        if not AggregateData.is_loaded:
            AggregateData.load()

        props = context.active_object.BIMObjectAggregateProperties

        if props.is_editing:
-            row = self.layout.row(align=True)
+            row = layout.row(align=True)
            row.prop(props, "relating_object", text="")
            if props.relating_object:
                op = row.operator("bim.assign_object", icon="CHECKMARK", text="")
@@ -57,15 +59,37 @@ class BIM_PT_aggregate(Panel):
                op.related_object = context.active_object.BIMObjectProperties.ifc_definition_id
            row.operator("bim.disable_editing_aggregate", icon="CANCEL", text="")
        else:
-            row = self.layout.row(align=True)
-            if AggregateData.data["has_aggregate"]:
-                row.label(text=AggregateData.data["label"])
+            row = layout.row(align=True)
+            if AggregateData.data["has_relating_object"]:
+                row.label(text=AggregateData.data["relating_object_label"], icon="TRIA_UP")
+                op = row.operator("bim.select_aggregate", icon="RESTRICT_SELECT_OFF", text="")
+                op.obj = context.active_object.name
                row.operator("bim.enable_editing_aggregate", icon="GREASEPENCIL", text="")
                row.operator("bim.add_aggregate", icon="ADD", text="")
                op = row.operator("bim.unassign_object", icon="X", text="")
                op.relating_object = AggregateData.data["relating_object_id"]
                op.related_object = context.active_object.BIMObjectProperties.ifc_definition_id
            else:
-                row.label(text="No Aggregate Found")
+                row.label(text="No Aggregate", icon="TRIA_UP")
                row.operator("bim.enable_editing_aggregate", icon="GREASEPENCIL", text="")
                row.operator("bim.add_aggregate", icon="ADD", text="")
+
+        row = layout.row(align=True)
+        parts = AggregateData.data["related_objects_amount"]
+        row.label(text=f"{parts or 'No'} Part{'s' if parts > 1 else ''}", icon="TRIA_DOWN")
+        if AggregateData.data["has_related_objects"]:
+            op = row.operator("bim.select_parts", icon="RESTRICT_SELECT_OFF", text="")
+            op.obj = context.active_object.name
+
+        ifc_class = AggregateData.data["ifc_class"]
+        part_class = ""
+        if ifc_class == "IfcBuilding":
+            part_class = "IfcBuildingStorey"
+        elif ifc_class == "IfcSite":
+            part_class = "IfcBuilding"
+        elif ifc_class == "IfcProject":
+            part_class = "IfcSite"
+        if part_class != "":
+            op = layout.operator("bim.add_part_to_object", text="Add " + part_class.lstrip("Ifc"))
+            op.part_class = part_class
+            op.obj = context.active_object.name
@@ -59,6 +59,7 @@ class BIM_PT_object_attributes(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_object_metadata"

    @classmethod
    def poll(cls, context):
@@ -26,6 +26,7 @@ class BIM_PT_augin(bpy.types.Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_integrations"

    def draw(self, context):
        layout = self.layout
@@ -842,6 +842,8 @@ class ActivateBcfViewpoint(bpy.types.Operator):
                obj.data.angle = 2 * atan(
                    (0.5 * cam_height) / (0.5 * cam_width / tan(radians(camera.field_of_view) / 2))
                )
+        else:
+            return

        z_axis = Vector(
            (-camera.camera_direction.x, -camera.camera_direction.y, -camera.camera_direction.z)
@@ -29,6 +29,7 @@ class BIM_PT_bcf(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_collaboration"

    def draw(self, context):
        layout = self.layout
@@ -19,7 +19,7 @@
 import os
 from pathlib import Path
 from blenderbim.bim.prop import StrProperty
-from blenderbim.bim.module.root.prop import getIfcClasses
+from blenderbim.bim.module.root.prop import get_ifc_classes
 from bpy.types import PropertyGroup
 from bpy.props import (
    PointerProperty,
@@ -33,14 +33,11 @@ from bpy.props import (
 )

 scenarios_enum = []
-classes_enum = []


 def purge():
    global scenarios_enum
-    global classes_enum
    scenarios_enum = []
-    classes_enum = []


 def getScenarios(self, context):
@@ -68,7 +65,7 @@ class BimTesterProperties(PropertyGroup):
    feature: StringProperty(default="", name="Feature / IDS", update=refreshScenarios)
    steps: StringProperty(default="", name="Custom Steps")
    ifc_file: StringProperty(default="", name="IFC File")
-    audit_ifc_class: EnumProperty(items=getIfcClasses, name="Audit Class")
+    audit_ifc_class: EnumProperty(items=get_ifc_classes, name="Audit Class")
    qa_reject_element_reason: StringProperty(name="Element Rejection Reason")
    scenario: EnumProperty(items=getScenarios, name="Scenario")
    should_load_from_memory: BoolProperty(default=False, name="Load from Memory")
@@ -27,6 +27,7 @@ class BIM_PT_qa(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_quality_control"

    def draw(self, context):
        self.layout.use_property_split = True
@@ -17,14 +17,28 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

 import bpy
-from . import ui
+from . import ui, operator, prop

-classes = (ui.BIM_PT_boundary,)
+classes = (
+    operator.LoadProjectSpaceBoundaries,
+    operator.LoadSpaceBoundaries,
+    operator.LoadBoundary,
+    operator.SelectProjectBoundaries,
+    operator.ColourByRelatedBuildingElement,
+    operator.EnableEditingBoundary,
+    operator.DisableEditingBoundary,
+    operator.EditBoundaryAttributes,
+    operator.UpdateBoundaryGeometry,
+    ui.BIM_PT_Boundary,
+    ui.BIM_PT_SpaceBoundaries,
+    ui.BIM_PT_SceneBoundaries,
+    prop.BIMBoundaryProperties,
+)


 def register():
-    pass
+    bpy.types.Object.bim_boundary_properties = bpy.props.PointerProperty(type=prop.BIMBoundaryProperties)


 def unregister():
-    pass
+    del bpy.types.Object.bim_boundary_properties
@@ -0,0 +1,290 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2020, 2021, 2022 Cyril Waechter <cyril@biminsight.ch>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+import logging
+import ifcopenshell.api
+import blenderbim.tool as tool
+from blenderbim.bim.ifc import IfcStore
+from ifcopenshell.api.boundary.data import Data
+import blenderbim.bim.import_ifc as import_ifc
+
+
+def get_boundaries_collection(blender_space):
+    space_collection = bpy.data.collections.get(blender_space.name)
+    collection_name = f"Boundaries/{blender_space.BIMObjectProperties.ifc_definition_id}"
+    boundaries_collection = space_collection.children.get(collection_name)
+    if not boundaries_collection:
+        boundaries_collection = bpy.data.collections.new(collection_name)
+        space_collection.children.link(boundaries_collection)
+    return boundaries_collection
+
+
+class Loader:
+    def __init__(self):
+        self.ifc_file = None
+        self.logger = None
+        self.ifc_importer = None
+        self.settings = None
+        self.load_settings()
+        self.load_importer()
+
+    def create_mesh(self, boundary):
+        # ConnectionGeometry is optional in IFC schema for some reasons.
+        if not boundary.ConnectionGeometry:
+            return None
+        surface = boundary.ConnectionGeometry.SurfaceOnRelatingElement
+        # workaround for unvalid geometry provided by Revit. See https://github.com/IfcOpenShell/IfcOpenShell/issues/635#issuecomment-770366838
+        if surface.is_a("IfcCurveBoundedPlane") and not getattr(surface, "InnerBoundaries", None):
+            surface.InnerBoundaries = ()
+        shape = ifcopenshell.geom.create_shape(self.settings, surface)
+        mesh = self.ifc_importer.create_mesh(None, shape)
+        self.ifc_importer.link_mesh(shape, mesh)
+        return mesh
+
+    def load_settings(self):
+        self.settings = ifcopenshell.geom.settings()
+        self.settings.set(self.settings.EXCLUDE_SOLIDS_AND_SURFACES, False)
+        self.settings.set(self.settings.USE_BREP_DATA, False)
+
+    def load_importer(self):
+        self.ifc_file = tool.Ifc.get()
+        self.logger = logging.getLogger("ImportIFC")
+        ifc_import_settings = import_ifc.IfcImportSettings.factory(bpy.context, IfcStore.path, self.logger)
+        self.ifc_importer = import_ifc.IfcImporter(ifc_import_settings)
+        self.ifc_importer.file = self.ifc_file
+
+    def load_boundary(self, boundary_id, blender_space):
+        boundary = self.ifc_file.by_id(boundary_id)
+        obj = tool.Ifc.get_object(boundary)
+        if obj:
+            return obj
+        mesh = self.create_mesh(boundary)
+        obj = bpy.data.objects.new(f"{boundary.is_a()}/{boundary.Name}", mesh)
+        obj.matrix_world = blender_space.matrix_world
+        boundaries_collection = get_boundaries_collection(blender_space)
+        boundaries_collection.objects.link(obj)
+        tool.Ifc.link(boundary, obj)
+        return obj
+
+
+class LoadProjectSpaceBoundaries(bpy.types.Operator):
+    bl_idname = "bim.load_project_space_boundaries"
+    bl_label = "Load all project space boundaries"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        loader = Loader()
+        if not Data.is_loaded:
+            Data.load(tool.Ifc.get())
+        for space_id, boundaries_id in Data.spaces.items():
+            blender_space = tool.Ifc.get_object(tool.Ifc.get().by_id(space_id))
+            for boundary_id in boundaries_id:
+                loader.load_boundary(boundary_id, blender_space)
+        return {"FINISHED"}
+
+
+class LoadBoundary(bpy.types.Operator):
+    bl_idname = "bim.load_boundary"
+    bl_label = "Load boundary"
+    bl_options = {"REGISTER", "UNDO"}
+    boundary_id: bpy.props.IntProperty()
+
+    def execute(self, context):
+        loader = Loader()
+        blender_space = context.active_object
+        for obj in context.visible_objects:
+            obj.select_set(False)
+        obj = loader.load_boundary(self.boundary_id, blender_space)
+        obj.select_set(True)
+        bpy.context.view_layer.objects.active = obj
+        return {"FINISHED"}
+
+
+class LoadSpaceBoundaries(bpy.types.Operator):
+    bl_idname = "bim.load_space_boundaries"
+    bl_label = "Load selected space boundaries"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        blender_space = context.active_object
+        oprops = context.active_object.BIMObjectProperties
+        loader = Loader()
+        if not Data.is_loaded:
+            Data.load(tool.Ifc.get())
+        for boundary_id in Data.spaces.get(oprops.ifc_definition_id, []):
+            loader.load_boundary(boundary_id, blender_space)
+        return {"FINISHED"}
+
+
+class SelectProjectBoundaries(bpy.types.Operator):
+    bl_idname = "bim.select_project_space_boundaries"
+    bl_label = "Select all project space boundaries"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        for obj in context.visible_objects:
+            obj.select_set(False)
+        ifc_file = tool.Ifc.get()
+        for boundary_id in Data.boundaries:
+            boundary = ifc_file.by_id(boundary_id)
+            obj = tool.Ifc.get_object(boundary)
+            if obj:
+                obj.select_set(True)
+        return {"FINISHED"}
+
+
+def get_colour(ifc_boundary):
+    """Return a color depending on IfcClass given"""
+    product_colors = {
+        "IfcWall": (0.7, 0.3, 0, 1),
+        "IfcWindow": (0, 0.7, 1, 1),
+        "IfcSlab": (0.7, 0.7, 0.5, 1),
+        "IfcRoof": (0, 0.3, 0, 1),
+        "IfcDoor": (1, 1, 1, 1),
+    }
+    if ifc_boundary.PhysicalOrVirtualBoundary == "VIRTUAL":
+        return (1, 0, 1, 1)
+
+    element = ifc_boundary.RelatedBuildingElement
+    if not element:
+        return (1, 0, 0, 1)
+    for product, colour in product_colors.items():
+        if element.is_a(product):
+            return colour
+    return (0, 0, 0, 1)
+
+
+class ColourByRelatedBuildingElement(bpy.types.Operator):
+    bl_idname = "bim.colour_by_related_building_element"
+    bl_label = "Apply colour based on related building elements"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        IfcStore.begin_transaction(self)
+        self.store_state(context)
+        result = self._execute(context)
+        IfcStore.add_transaction_operation(self)
+        IfcStore.end_transaction(self)
+        return result
+
+    def _execute(self, context):
+        self.file = tool.Ifc.get()
+        for obj in context.visible_objects:
+            if not obj.BIMObjectProperties.ifc_definition_id:
+                continue
+            element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+            if not element.is_a("IfcRelSpaceBoundary"):
+                continue
+            obj.color = get_colour(element)
+        areas = [a for a in context.screen.areas if a.type == "VIEW_3D"]
+        if areas:
+            areas[0].spaces[0].shading.color_type = "OBJECT"
+        return {"FINISHED"}
+
+    def store_state(self, context):
+        areas = [a for a in context.screen.areas if a.type == "VIEW_3D"]
+        if areas:
+            self.transaction_data = {"area": areas[0], "color_type": areas[0].spaces[0].shading.color_type}
+
+    def rollback(self, data):
+        if data:
+            data["area"].spaces[0].shading.color_type = data["color_type"]
+
+    def commit(self, data):
+        if data:
+            data["area"].spaces[0].shading.color_type = "OBJECT"
+
+
+EDITABLE_ATTRIBUTES = {
+    "RelatingSpace": "relating_space",
+    "RelatedBuildingElement": "related_building_element",
+    "ParentBoundary": "parent_boundary",
+    "CorrespondingBoundary": "corresponding_boundary",
+}
+
+
+class EnableEditingBoundary(bpy.types.Operator):
+    bl_idname = "bim.enable_editing_boundary"
+    bl_label = "Edit boundary relations"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        bprops = context.active_object.bim_boundary_properties
+        bprops.is_editing = True
+        boundary = tool.Ifc.get_entity(context.active_object)
+        for ifc_attribute, blender_property in EDITABLE_ATTRIBUTES.items():
+            entity = getattr(boundary, ifc_attribute, None)
+            if not entity:
+                continue
+            obj = tool.Ifc.get_object(entity)
+            if entity and obj:
+                setattr(bprops, blender_property, obj)
+        return {"FINISHED"}
+
+
+class DisableEditingBoundary(bpy.types.Operator):
+    bl_idname = "bim.disable_editing_boundary"
+    bl_label = "Disable editing boundary relations"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        bprops = context.active_object.bim_boundary_properties
+        bprops.is_editing = False
+        for ifc_attribute, blender_property in EDITABLE_ATTRIBUTES.items():
+            setattr(bprops, blender_property, None)
+        return {"FINISHED"}
+
+
+class EditBoundaryAttributes(bpy.types.Operator):
+    bl_idname = "bim.edit_boundary_attributes"
+    bl_label = "Disable editing boundary relations"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        return IfcStore.execute_ifc_operator(self, context)
+
+    def _execute(self, context):
+        bprops = context.active_object.bim_boundary_properties
+        boundary = tool.Ifc.get_entity(context.active_object)
+        attributes = dict()
+        for ifc_attribute, blender_property in EDITABLE_ATTRIBUTES.items():
+            obj = getattr(bprops, blender_property, None)
+            entity = tool.Ifc.get_entity(obj)
+            attributes[blender_property] = entity
+        ifcopenshell.api.run("boundary.edit_attributes", tool.Ifc.get(), entity=boundary, **attributes)
+        bpy.ops.bim.disable_editing_boundary()
+        return {"FINISHED"}
+
+
+class UpdateBoundaryGeometry(bpy.types.Operator):
+    bl_idname = "bim.update_boundary_geometry"
+    bl_label = "Update boundary geometry"
+    bl_description = """
+    Update boundary connection geometry from mesh.
+    Mesh must lie on a single plane. It should look like a face or a face with holes.
+    """
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        return IfcStore.execute_ifc_operator(self, context)
+
+    def _execute(self, context):
+        settings = tool.Boundary.get_assign_connection_geometry_settings(context.active_object)
+        ifcopenshell.api.run("boundary.assign_connection_geometry", tool.Ifc.get(), **settings)
+        return {"FINISHED"}
@@ -0,0 +1,60 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+from bpy.types import PropertyGroup
+from bpy.props import (
+    PointerProperty,
+    StringProperty,
+    EnumProperty,
+    BoolProperty,
+    IntProperty,
+    FloatProperty,
+    FloatVectorProperty,
+    CollectionProperty,
+)
+import blenderbim.tool as tool
+
+
+def space_filter(self, object):
+    entity = tool.Ifc.get_entity(object)
+    if entity:
+        return entity.is_a("IfcSpace") or entity.is_a("IfcExternalSpatialElement")
+    return False
+
+
+def boundary_filter(self, object):
+    entity = tool.Ifc.get_entity(object)
+    if entity:
+        return entity.is_a("IfcRelSpaceBoundary")
+    return False
+
+
+def element_filter(self, object):
+    entity = tool.Ifc.get_entity(object)
+    if entity:
+        return entity.is_a("IfcElement")
+    return False
+
+
+class BIMBoundaryProperties(PropertyGroup):
+    is_editing: BoolProperty(name="Is Editing")
+    relating_space: PointerProperty(name="RelatingSpace", type=bpy.types.Object, poll=space_filter)
+    related_building_element: PointerProperty(name="RelatedBuildingElement", type=bpy.types.Object, poll=element_filter)
+    parent_boundary: PointerProperty(name="ParentBoundary", type=bpy.types.Object, poll=boundary_filter)
+    corresponding_boundary: PointerProperty(name="CorrespondingBoundary", type=bpy.types.Object, poll=boundary_filter)
@@ -20,16 +20,37 @@ import bpy
 import blenderbim.bim.helper
 from bpy.types import Panel, UIList
 from blenderbim.bim.ifc import IfcStore
+import blenderbim.tool as tool
 from ifcopenshell.api.boundary.data import Data


-class BIM_PT_boundary(Panel):
+class BIM_PT_SceneBoundaries(Panel):
    bl_label = "IFC Space Boundaries"
-    bl_idname = "BIM_PT_boundary"
+    bl_id_name = "BIM_PT_scene_boundaries"
    bl_options = {"DEFAULT_CLOSED"}
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
+    bl_context = "scene"
+    bl_parent_id = "BIM_PT_geometry"
+
+    @classmethod
+    def poll(cls, context):
+        return IfcStore.get_file()
+
+    def draw(self, context):
+        row = self.layout.row(align=True)
+        row.operator("bim.load_project_space_boundaries")
+        row.operator("bim.select_project_space_boundaries", text="", icon="RESTRICT_SELECT_OFF")
+        row.operator("bim.colour_by_related_building_element", text="", icon="BRUSH_DATA")
+
+
+class BIM_PT_Boundary(Panel):
+    bl_label = "IFC Space Boundary"
+    bl_idname = "BIM_PT_Boundary"
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_geometry_object"

    @classmethod
    def poll(cls, context):
@@ -40,15 +61,97 @@ class BIM_PT_boundary(Panel):
            return False
        if not IfcStore.get_element(props.ifc_definition_id):
            return False
-        if IfcStore.get_file().by_id(props.ifc_definition_id).is_a() not in ["IfcSpace", "IfcExternalSpatialElement"]:
-            return False
-        return True
+        entity = IfcStore.get_file().by_id(props.ifc_definition_id)
+        return entity.is_a("IfcRelSpaceBoundary")

    def draw(self, context):
-        self.oprops = context.active_object.BIMObjectProperties
-        if not Data.is_loaded:
-            Data.load(IfcStore.get_file())
-        for boundary_id in Data.spaces.get(self.oprops.ifc_definition_id, []):
-            boundary = Data.boundaries[boundary_id]
+        props = context.active_object.BIMObjectProperties
+        ifc_file = tool.Ifc.get()
+        element = ifc_file.by_id(props.ifc_definition_id)
+        boundary = ifc_file.by_id(props.ifc_definition_id)
+        self.bprops = context.active_object.bim_boundary_properties
+        if self.bprops.is_editing:
+            row = self.layout.row(align=True)
+            row.operator("bim.edit_boundary_attributes", icon="CHECKMARK", text="Save Attributes")
+            row.operator("bim.disable_editing_boundary", icon="CANCEL", text="")
+            self.draw_relation_editor(boundary, "RelatingSpace", "relating_space")
+            self.draw_relation_editor(boundary, "RelatedBuildingElement", "related_building_element")
+            self.draw_relation_editor(boundary, "ParentBoundary", "parent_boundary")
+            self.draw_relation_editor(boundary, "CorrespondingBoundary", "corresponding_boundary")
+        else:
            row = self.layout.row()
-            row.label(text=f"{boundary_id}", icon="GHOST_ENABLED")
+            row.operator("bim.enable_editing_boundary", icon="GREASEPENCIL", text="Edit")
+            self.draw_relation_data(boundary, "RelatingSpace")
+            self.draw_relation_data(boundary, "RelatedBuildingElement")
+            self.draw_relation_data(boundary, "ParentBoundary")
+            self.draw_relation_data(boundary, "CorrespondingBoundary")
+            if hasattr(boundary, "InnerBoundaries"):
+                for i, inner_boundary in enumerate(getattr(boundary, "InnerBoundaries", ())):
+                    row = self.layout.row(align=True)
+                    row.label(text="InnerBoundaries")
+                    row.label(text=f"[{i}]")
+                    row.label(text=f"{inner_boundary.is_a()}/{inner_boundary.Name}")
+        row = self.layout.row()
+        row.operator("bim.update_boundary_geometry")
+
+    def draw_relation_data(self, boundary, ifc_attribute: str):
+        row = self.layout.row(align=True)
+        if hasattr(boundary, ifc_attribute):
+            row.label(text=ifc_attribute)
+            entity = getattr(boundary, ifc_attribute)
+            if entity:
+                row.label(text=f"{entity.is_a()}/{entity.Name}")
+                op = row.operator("bim.select_global_id", text="", icon="TRACKER")
+                op.global_id = entity.GlobalId
+            else:
+                row.label(text="")
+
+    def draw_relation_editor(self, boundary, ifc_attribute: str, blender_property: str):
+        if hasattr(boundary, ifc_attribute):
+            row = self.layout.row(align=True)
+            row.prop(self.bprops, blender_property)
+
+
+class BIM_PT_SpaceBoundaries(Panel):
+    bl_label = "IFC Space Boundaries"
+    bl_idname = "BIM_PT_SpaceBoundaries"
+    bl_options = {"DEFAULT_CLOSED"}
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+    bl_context = "object"
+    bl_parent_id = "BIM_PT_geometry_object"
+
+    @classmethod
+    def poll(cls, context):
+        if not context.active_object:
+            return False
+        props = context.active_object.BIMObjectProperties
+        if not props.ifc_definition_id:
+            return False
+        if not IfcStore.get_element(props.ifc_definition_id):
+            return False
+        valid_classes = ("IfcSpace", "IfcExternalSpatialElement")
+        entity = IfcStore.get_file().by_id(props.ifc_definition_id)
+        for ifc_class in valid_classes:
+            if entity.is_a(ifc_class):
+                return True
+        return False
+
+    def draw(self, context):
+        self.props = context.active_object.BIMObjectProperties
+        self.ifc_file = tool.Ifc.get()
+        row = self.layout.row()
+        row.operator("bim.load_space_boundaries")
+        if not Data.is_loaded:
+            Data.load(self.ifc_file)
+        for boundary_id in Data.spaces.get(self.props.ifc_definition_id, []):
+            boundary_data = Data.boundaries[boundary_id]
+            building_element = self.ifc_file.by_id(boundary_data["RelatedBuildingElement"])
+            row = self.layout.row()
+            if building_element:
+                bld_el_description = f"{building_element.is_a()}/{building_element.Name}"
+            else:
+                bld_el_description = None
+            row.label(text=f"{boundary_id} > {bld_el_description}", icon="GHOST_ENABLED")
+            op = row.operator("bim.load_boundary", text="", icon="RESTRICT_SELECT_OFF")
+            op.boundary_id = boundary_id
@@ -0,0 +1,49 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+from . import ui, prop, operator
+
+classes = (
+    operator.AddBrick,
+    operator.AddBrickFeed,
+    operator.AssignBrickReference,
+    operator.CloseBrickProject,
+    operator.ConvertBrickProject,
+    operator.ConvertIfcToBrick,
+    operator.LoadBrickProject,
+    operator.NewBrickFile,
+    operator.RefreshBrickViewer,
+    operator.RemoveBrick,
+    operator.RewindBrickClass,
+    operator.ViewBrickClass,
+    operator.ViewBrickItem,
+    prop.Brick,
+    prop.BIMBrickProperties,
+    ui.BIM_PT_brickschema,
+    ui.BIM_PT_ifc_brickschema_references,
+    ui.BIM_UL_bricks,
+)
+
+
+def register():
+    bpy.types.Scene.BIMBrickProperties = bpy.props.PointerProperty(type=prop.BIMBrickProperties)
+
+
+def unregister():
+    del bpy.types.Scene.BIMBrickProperties
@@ -0,0 +1,180 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+import blenderbim.tool as tool
+from blenderbim.tool.brick import BrickStore
+
+try:
+    from rdflib import URIRef, BNode
+except:
+    # See #1860
+    print("Warning: brickschema not available.")
+
+
+def refresh():
+    BrickschemaData.is_loaded = False
+    BrickschemaReferencesData.is_loaded = False
+
+
+class BrickschemaData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.is_loaded = True
+        cls.data = {
+            "is_loaded": cls.get_is_loaded(),
+            "attributes": cls.attributes(),
+            "namespaces": cls.namespaces(),
+            "brick_equipment_classes": cls.brick_equipment_classes(),
+        }
+
+    @classmethod
+    def get_is_loaded(cls):
+        return BrickStore.graph is not None
+
+    @classmethod
+    def attributes(cls):
+        if BrickStore.graph is None:
+            return []
+        props = bpy.context.scene.BIMBrickProperties
+        try:
+            brick = props.bricks[props.active_brick_index]
+        except:
+            return []
+        results = []
+        uri = brick.uri
+        query = BrickStore.graph.query(
+            """
+            PREFIX brick: <https://brickschema.org/schema/Brick#>
+            PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
+            PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
+            SELECT DISTINCT ?name ?value ?sp ?sv WHERE {
+               <{uri}> ?name ?value .
+               OPTIONAL {
+               { ?name rdfs:range brick:TimeseriesReference . }
+                UNION
+               { ?name a brick:EntityProperty . }
+                ?value ?sp ?sv }
+            }
+        """.replace(
+                "{uri}", uri
+            )
+        )
+
+        for row in query:
+            name = row.get("name").toPython().split("#")[-1]
+            value = row.get("value")
+            results.append(
+                {
+                    "name": name,
+                    "value": value.toPython().split("#")[-1],
+                    "is_uri": isinstance(value, URIRef),
+                    "value_uri": value.toPython(),
+                    "is_globalid": name == "globalID",
+                }
+            )
+            if isinstance(row.get("value"), BNode):
+                for s, p, o in BrickStore.graph.triples((value, None, None)):
+                    results.append(
+                        {
+                            "name": name + ":" + p.toPython().split("#")[-1],
+                            "value": o.toPython().split("#")[-1],
+                            "is_uri": isinstance(o, URIRef),
+                            "value_uri": o.toPython(),
+                            "is_globalid": p.toPython().split("#")[-1] == "globalID",
+                        }
+                    )
+        return results
+
+    @classmethod
+    def namespaces(cls):
+        if BrickStore.graph is None:
+            return []
+        results = []
+        for alias, uri in BrickStore.graph.namespaces():
+            results.append((uri, f"{alias}: {uri}", ""))
+        return results
+
+    @classmethod
+    def brick_equipment_classes(cls):
+        if BrickStore.graph is None:
+            return []
+        results = []
+        query = BrickStore.graph.query(
+            """
+            PREFIX brick: <https://brickschema.org/schema/Brick#>
+            PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
+            SELECT ?class WHERE {
+                ?class rdfs:subClassOf* brick:Equipment .
+            }
+        """
+        )
+        for uri in sorted([x[0].toPython() for x in query]):
+            results.append((uri, uri.split("#")[-1], ""))
+        return results
+
+
+class BrickschemaReferencesData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.is_loaded = True
+        cls.data = {"is_loaded": cls.get_is_loaded(), "libraries": cls.libraries(), "references": cls.references()}
+
+    @classmethod
+    def get_is_loaded(cls):
+        return BrickStore.graph is not None
+
+    @classmethod
+    def libraries(cls):
+        results = []
+        ifc = tool.Ifc.get()
+        if not ifc:
+            return results
+        for library in ifc.by_type("IfcLibraryInformation"):
+            if tool.Ifc.get_schema() == "IFC2X3":
+                results.append((str(library.id()), library.Name or "Unnamed", ""))
+            elif ".ttl" in library.Location:
+                results.append((str(library.id()), library.Name or "Unnamed", ""))
+        return results
+
+    @classmethod
+    def references(cls):
+        results = []
+        for rel in getattr(tool.Ifc.get_entity(bpy.context.active_object), "HasAssociations", []):
+            if rel.is_a("IfcRelAssociatesLibrary"):
+                reference = rel.RelatingLibrary
+                if tool.Ifc.get_schema() == "IFC2X3" and "#" not in reference.ItemReference:
+                    continue
+                if tool.Ifc.get_schema() != "IFC2X3" and "#" not in reference.Identification:
+                    continue
+                results.append(
+                    {
+                        "id": reference.id(),
+                        "identification": reference.ItemReference
+                        if tool.Ifc.get_schema() == "IFC2X3"
+                        else reference.Identification,
+                        "name": reference.Name or "Unnamed",
+                    }
+                )
+        return results
@@ -0,0 +1,191 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+import ifcopenshell.api
+import blenderbim.tool as tool
+import blenderbim.core.brick as core
+import blenderbim.bim.handler
+from blenderbim.bim.ifc import IfcStore
+
+
+class Operator:
+    def execute(self, context):
+        self._execute(context)
+        blenderbim.bim.handler.refresh_ui_data()
+        return {"FINISHED"}
+
+
+class LoadBrickProject(bpy.types.Operator, Operator):
+    bl_idname = "bim.load_brick_project"
+    bl_label = "Load Brickschema Project"
+    bl_options = {"REGISTER", "UNDO"}
+    filepath: bpy.props.StringProperty(subtype="FILE_PATH")
+    filter_glob: bpy.props.StringProperty(default="*.ttl", options={"HIDDEN"})
+
+    def _execute(self, context):
+        core.load_brick_project(tool.Brick, filepath=self.filepath)
+
+    def invoke(self, context, event):
+        context.window_manager.fileselect_add(self)
+        return {"RUNNING_MODAL"}
+
+
+class ViewBrickClass(bpy.types.Operator, Operator):
+    bl_idname = "bim.view_brick_class"
+    bl_label = "View Brick Class"
+    bl_options = {"REGISTER", "UNDO"}
+    brick_class: bpy.props.StringProperty(name="Brick Class")
+
+    def _execute(self, context):
+        core.view_brick_class(tool.Brick, brick_class=self.brick_class)
+
+
+class ViewBrickItem(bpy.types.Operator, Operator):
+    bl_idname = "bim.view_brick_item"
+    bl_label = "View Brick Item"
+    bl_options = {"REGISTER", "UNDO"}
+    item: bpy.props.StringProperty(name="Brick Item")
+
+    def _execute(self, context):
+        core.view_brick_item(tool.Brick, item=self.item)
+
+
+class RewindBrickClass(bpy.types.Operator, Operator):
+    bl_idname = "bim.rewind_brick_class"
+    bl_label = "Rewind Brick Class"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.rewind_brick_class(tool.Brick)
+
+
+class CloseBrickProject(bpy.types.Operator, Operator):
+    bl_idname = "bim.close_brick_project"
+    bl_label = "Close Brick Project"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.close_brick_project(tool.Brick)
+
+
+class ConvertBrickProject(bpy.types.Operator, Operator):
+    bl_idname = "bim.convert_brick_project"
+    bl_label = "Convert Brick Project"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.convert_brick_project(tool.Ifc, tool.Brick)
+
+
+class AssignBrickReference(bpy.types.Operator, Operator):
+    bl_idname = "bim.assign_brick_reference"
+    bl_label = "Assign Brick Reference"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        props = context.scene.BIMBrickProperties
+        core.assign_brick_reference(
+            tool.Ifc,
+            tool.Brick,
+            element=tool.Ifc.get_entity(context.active_object),
+            library=tool.Ifc.get().by_id(int(props.libraries)),
+            brick_uri=props.bricks[props.active_brick_index].uri,
+        )
+
+
+class AddBrick(bpy.types.Operator, Operator):
+    bl_idname = "bim.add_brick"
+    bl_label = "Add Brick"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        props = context.scene.BIMBrickProperties
+        library = None
+        if props.libraries:
+            library = tool.Ifc.get().by_id(int(props.libraries))
+        core.add_brick(
+            tool.Ifc,
+            tool.Brick,
+            element=tool.Ifc.get_entity(context.active_object) if context.selected_objects else None,
+            namespace=props.namespace,
+            brick_class=props.brick_equipment_class,
+            library=library,
+        )
+
+
+class AddBrickFeed(bpy.types.Operator, Operator):
+    bl_idname = "bim.add_brick_feed"
+    bl_label = "Add Brick Feed"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        source = tool.Ifc.get_entity([o for o in context.selected_objects if o != context.active_object][0])
+        destination = tool.Ifc.get_entity(context.active_object)
+        core.add_brick_feed(
+            tool.Ifc,
+            tool.Brick,
+            source=source,
+            destination=destination,
+        )
+
+
+class ConvertIfcToBrick(bpy.types.Operator, Operator):
+    bl_idname = "bim.convert_ifc_to_brick"
+    bl_label = "Convert IFC To Brick"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        props = context.scene.BIMBrickProperties
+        library = None
+        if props.libraries:
+            library = tool.Ifc.get().by_id(int(props.libraries))
+        core.convert_ifc_to_brick(tool.Brick, namespace=props.namespace, library=library)
+
+
+class NewBrickFile(bpy.types.Operator, Operator):
+    bl_idname = "bim.new_brick_file"
+    bl_label = "New Brick File"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.new_brick_file(tool.Brick)
+
+
+class RefreshBrickViewer(bpy.types.Operator, Operator):
+    bl_idname = "bim.refresh_brick_viewer"
+    bl_label = "Refresh Brick Viewer"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.refresh_brick_viewer(tool.Brick)
+
+
+class RemoveBrick(bpy.types.Operator, Operator):
+    bl_idname = "bim.remove_brick"
+    bl_label = "Remove Brick"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        props = context.scene.BIMBrickProperties
+        core.remove_brick(
+            tool.Ifc,
+            tool.Brick,
+            library=tool.Ifc.get().by_id(int(props.libraries)) if props.libraries else None,
+            brick_uri=props.bricks[props.active_brick_index].uri,
+        )
@@ -0,0 +1,71 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+from blenderbim.bim.module.brick.data import BrickschemaData, BrickschemaReferencesData
+from blenderbim.bim.prop import StrProperty, Attribute
+from bpy.types import PropertyGroup
+from bpy.props import (
+    PointerProperty,
+    StringProperty,
+    EnumProperty,
+    BoolProperty,
+    IntProperty,
+    FloatProperty,
+    FloatVectorProperty,
+    CollectionProperty,
+)
+
+
+def update_active_brick_index(self, context):
+    BrickschemaData.is_loaded = False
+
+
+def get_libraries(self, context):
+    if not BrickschemaReferencesData.is_loaded:
+        BrickschemaReferencesData.load()
+    return BrickschemaReferencesData.data["libraries"]
+
+
+def get_namespaces(self, context):
+    if not BrickschemaData.is_loaded:
+        BrickschemaData.load()
+    return BrickschemaData.data["namespaces"]
+
+
+def get_brick_equipment_classes(self, context):
+    if not BrickschemaData.is_loaded:
+        BrickschemaData.load()
+    return BrickschemaData.data["brick_equipment_classes"]
+
+
+class Brick(PropertyGroup):
+    name: StringProperty(name="Name")
+    label: StringProperty(name="Label")
+    uri: StringProperty(name="URI")
+    total_items: IntProperty(name="Total Items")
+
+
+class BIMBrickProperties(PropertyGroup):
+    active_brick_class: StringProperty(name="Active Brick Class")
+    brick_breadcrumbs: CollectionProperty(name="Brick Breadcrumbs", type=StrProperty)
+    bricks: CollectionProperty(name="Bricks", type=Brick)
+    active_brick_index: IntProperty(name="Active Brick Index", update=update_active_brick_index)
+    libraries: EnumProperty(name="Libraries", items=get_libraries)
+    namespace: EnumProperty(name="Namespace", items=get_namespaces)
+    brick_equipment_class: EnumProperty(name="Brick Equipment Class", items=get_brick_equipment_classes)
@@ -0,0 +1,132 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import blenderbim.tool as tool
+from bpy.types import Panel, UIList
+from blenderbim.bim.module.brick.data import BrickschemaData, BrickschemaReferencesData
+
+
+class BIM_PT_brickschema(Panel):
+    bl_label = "Brickschema Project"
+    bl_idname = "BIM_PT_brickschema"
+    bl_options = {"DEFAULT_CLOSED"}
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+    bl_context = "scene"
+
+    def draw(self, context):
+        if not BrickschemaData.is_loaded:
+            BrickschemaData.load()
+        self.props = context.scene.BIMBrickProperties
+
+        if not BrickschemaData.data["is_loaded"]:
+            row = self.layout.row(align=True)
+            row.operator("bim.new_brick_file", text="Create Project")
+            row.operator("bim.load_brick_project", text="Load Project")
+            return
+
+        row = self.layout.row(align=True)
+        if len(self.props.brick_breadcrumbs):
+            row.operator("bim.rewind_brick_class", text="", icon="FRAME_PREV")
+        row.label(text=self.props.active_brick_class)
+        row.operator("bim.refresh_brick_viewer", text="", icon="FILE_REFRESH")
+        row.operator("bim.close_brick_project", text="", icon="CANCEL")
+
+        row = self.layout.row(align=True)
+        row.prop(self.props, "namespace", text="")
+        row.prop(self.props, "brick_equipment_class", text="")
+        row.operator("bim.add_brick", text="", icon="ADD")
+
+        row = self.layout.row(align=True)
+        row.alignment = "RIGHT"
+        row.operator("bim.add_brick_feed", text="", icon="PLUGIN")
+        row.operator("bim.remove_brick", text="", icon="X")
+
+        self.layout.template_list("BIM_UL_bricks", "", self.props, "bricks", self.props, "active_brick_index")
+
+        for attribute in BrickschemaData.data["attributes"]:
+            row = self.layout.row(align=True)
+            row.label(text=attribute["name"])
+            row.label(text=attribute["value"])
+            if attribute["is_uri"]:
+                op = row.operator("bim.view_brick_item", text="", icon="DISCLOSURE_TRI_RIGHT")
+                op.item = attribute["value_uri"]
+            if attribute["is_globalid"]:
+                op = row.operator("bim.select_global_id", icon="RESTRICT_SELECT_OFF", text="")
+                op.global_id = attribute["value"]
+
+
+class BIM_PT_ifc_brickschema_references(Panel):
+    bl_label = "IFC Brickschema References"
+    bl_idname = "BIM_PT_ifc_brickschema_references"
+    bl_options = {"DEFAULT_CLOSED"}
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+    bl_context = "scene"
+    bl_parent_id = "BIM_PT_brickschema"
+
+    @classmethod
+    def poll(cls, context):
+        return tool.Ifc.get()
+
+    def draw(self, context):
+        if not BrickschemaReferencesData.is_loaded:
+            BrickschemaReferencesData.load()
+        self.props = context.scene.BIMBrickProperties
+
+        if not BrickschemaReferencesData.data["is_loaded"]:
+            row = self.layout.row()
+            row.label(text="No Brickschema Project Loaded")
+            return
+
+        if not BrickschemaReferencesData.data["libraries"]:
+            row = self.layout.row(align=True)
+            row.label(text="No IFC Libraries")
+            row.operator("bim.convert_brick_project", text="", icon="ADD")
+            return
+
+        row = self.layout.row(align=True)
+        row.prop(self.props, "libraries")
+        row.operator("bim.convert_brick_project", text="", icon="ADD")
+
+        row = self.layout.row(align=True)
+        row.operator("bim.assign_brick_reference", icon="ADD")
+        row.operator("bim.convert_ifc_to_brick", icon="IMPORT")
+
+        if not BrickschemaReferencesData.data["references"]:
+            row = self.layout.row()
+            row.label(text="No References")
+
+        for reference in BrickschemaReferencesData.data["references"]:
+            row = self.layout.row(align=True)
+            row.label(text=reference["identification"], icon="ASSET_MANAGER")
+            row.label(text=reference["name"])
+            row.operator("bim.unassign_library_reference", text="", icon="X").reference = reference["id"]
+            row.operator("bim.view_brick_item", text="", icon="DISCLOSURE_TRI_RIGHT").item = reference["identification"]
+
+
+class BIM_UL_bricks(UIList):
+    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
+        if item:
+            row = layout.row(align=True)
+            if item.total_items:
+                op = row.operator("bim.view_brick_class", text="", icon="DISCLOSURE_TRI_RIGHT", emboss=False)
+                op.brick_class = item.name
+            row.label(text=item.label if item.label else item.name)
+            if item.total_items:
+                row.label(text=str(item.total_items))
@@ -34,9 +34,6 @@ classes = (
    operator.SmartClashGroup,
    operator.SelectSmartGroup,
    operator.LoadSmartGroupsForActiveClashSet,
-    operator.SetBlenderClashSetA,
-    operator.SetBlenderClashSetB,
-    operator.ExecuteBlenderClash,
    prop.ClashSource,
    prop.ClashSet,
    prop.SmartClashGroup,
@@ -411,82 +411,3 @@ class SelectSmartGroup(bpy.types.Operator):
                    obj.select_set(True)

        return {"FINISHED"}
-
-
-class BlenderClasher:
-    def process_clash_set(self, context):
-        import collision
-
-        a_cm = collision.CollisionManager()
-        b_cm = collision.CollisionManager()
-        self.add_to_cm(a_cm, context.scene.BIMClashProperties.blender_clash_set_a, context)
-        self.add_to_cm(b_cm, context.scene.BIMClashProperties.blender_clash_set_b, context)
-        results = a_cm.in_collision_other(b_cm, return_data=True)
-        if not results[0]:
-            print("No clashes")
-            return
-        for contact in results[1]:
-            if contact.raw.penetration_depth < 0.01:
-                continue
-            print("-----")
-            print(contact.names)
-            print(contact.raw.normal)
-            print(contact.raw.pos)
-
-    def add_to_cm(self, cm, object_names, context):
-        import ifcclash
-
-        for object_name in object_names:
-            name = object_name.name
-            obj = bpy.data.objects[name]
-            triangulated_mesh = self.triangulate_mesh(obj, context)
-            mesh = ifcclash.Mesh()
-            mesh.vertices = np.array([tuple(obj.matrix_world @ v.co) for v in triangulated_mesh.vertices])
-            mesh.faces = np.array([tuple(p.vertices) for p in triangulated_mesh.polygons])
-            cm.add_object(name, mesh)
-
-    def triangulate_mesh(self, obj, context):
-        mesh = obj.evaluated_get(context.evaluated_depsgraph_get()).to_mesh()
-        bm = bmesh.new()
-        bm.from_mesh(mesh)
-        bmesh.ops.triangulate(bm, faces=bm.faces)
-        bm.to_mesh(mesh)
-        bm.free()
-        del bm
-        return mesh
-
-
-class SetBlenderClashSetA(bpy.types.Operator):
-    bl_idname = "bim.set_blender_clash_set_a"
-    bl_label = "Set Blender Clash Set A"
-    bl_options = {"REGISTER", "UNDO"}
-
-    def execute(self, context):
-        context.scene.BIMClashProperties.blender_clash_set_a.clear()
-        for obj in context.selected_objects:
-            new = context.scene.BIMClashProperties.blender_clash_set_a.add()
-            new.name = obj.name
-        return {"FINISHED"}
-
-
-class SetBlenderClashSetB(bpy.types.Operator):
-    bl_idname = "bim.set_blender_clash_set_b"
-    bl_label = "Set Blender Clash Set B"
-    bl_options = {"REGISTER", "UNDO"}
-
-    def execute(self, context):
-        context.scene.BIMClashProperties.blender_clash_set_b.clear()
-        for obj in context.selected_objects:
-            new = context.scene.BIMClashProperties.blender_clash_set_b.add()
-            new.name = obj.name
-        return {"FINISHED"}
-
-
-class ExecuteBlenderClash(bpy.types.Operator):
-    bl_idname = "bim.execute_blender_clash"
-    bl_label = "Execute Blender Clash"
-
-    def execute(self, context):
-        blender_clasher = BlenderClasher()
-        blender_clasher.process_clash_set(context)
-        return {"FINISHED"}
@@ -27,6 +27,7 @@ class BIM_PT_ifcclash(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_quality_control"

    def draw(self, context):
        layout = self.layout
@@ -34,17 +35,6 @@ class BIM_PT_ifcclash(Panel):
        scene = context.scene
        props = scene.BIMClashProperties

-        layout.label(text="Blender Clash:")
-
-        row = layout.row(align=True)
-        row.operator("bim.set_blender_clash_set_a")
-        row.operator("bim.set_blender_clash_set_b")
-
-        row = layout.row(align=True)
-        row.operator("bim.execute_blender_clash")
-
-        layout.label(text="IFC Clash:")
-
        row = layout.row(align=True)
        row.operator("bim.add_clash_set")
        row.operator("bim.import_clash_sets", text="", icon="IMPORT")
@@ -29,6 +29,7 @@ class BIM_PT_classifications(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_project_setup"

    @classmethod
    def poll(cls, context):
@@ -86,6 +87,7 @@ class BIM_PT_classification_references(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_object_metadata"

    @classmethod
    def poll(cls, context):
@@ -27,6 +27,7 @@ class BIM_PT_cobie(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_collaboration"

    def draw(self, context):
        layout = self.layout
@@ -29,6 +29,7 @@ class BIM_PT_constraints(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_project_setup"

    @classmethod
    def poll(cls, context):
@@ -73,6 +74,7 @@ class BIM_PT_object_constraints(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_misc_object"

    @classmethod
    def poll(cls, context):
@@ -29,6 +29,7 @@ class BIM_PT_context(bpy.types.Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_geometry"

    @classmethod
    def poll(cls, context):
@@ -31,6 +31,7 @@ class BIM_PT_cost_schedules(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_4D5D"

    @classmethod
    def poll(cls, context):
@@ -26,6 +26,7 @@ class BIM_PT_covetool(bpy.types.Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_integrations"

    def draw(self, context):
        layout = self.layout
@@ -170,6 +170,8 @@ class ImportIfcCsv(bpy.types.Operator):
        else:
            ifc_csv.delimiter = props.csv_delimiter
        ifc_csv.Import(ifc_file)
+        if not props.should_load_from_memory:
+            ifc_file.write(props.csv_ifc_file)
        purge_module_data()
        return {"FINISHED"}

@@ -27,6 +27,7 @@ class BIM_PT_ifccsv(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_collaboration"

    def draw(self, context):
        layout = self.layout
@@ -20,17 +20,21 @@ import bpy
 from . import ui, prop, operator

 classes = (
-    operator.PrintIfcFile,
-    operator.PurgeIfcLinks,
-    operator.PrintObjectPlacement,
-    operator.ValidateIfcFile,
-    operator.ProfileImportIFC,
    operator.CreateAllShapes,
    operator.CreateShapeFromStepId,
-    operator.SelectHighPolygonMeshes,
-    operator.InspectFromStepId,
    operator.InspectFromObject,
+    operator.InspectFromStepId,
+    operator.ParseExpress,
+    operator.PrintIfcFile,
+    operator.PrintObjectPlacement,
+    operator.ProfileImportIFC,
+    operator.PurgeHdf5Cache,
+    operator.PurgeIfcLinks,
    operator.RewindInspector,
+    operator.SelectExpressFile,
+    operator.SelectHighPolygonMeshes,
+    operator.SelectHighestPolygonMeshes,
+    operator.ValidateIfcFile,
    prop.BIMDebugProperties,
    ui.BIM_PT_debug,
 )
@@ -16,20 +16,25 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

+import os
 import bpy
 import time
 import logging
 import ifcopenshell
 import ifcopenshell.util.placement
 import ifcopenshell.util.representation
+import blenderbim.tool as tool
+import blenderbim.core.debug as core
 import blenderbim.bim.handler
 import blenderbim.bim.import_ifc as import_ifc
+import blenderbim.tool as tool
 from blenderbim.bim.ifc import IfcStore


 class PrintIfcFile(bpy.types.Operator):
    bl_idname = "bim.print_ifc_file"
    bl_label = "Print IFC File"
+    bl_description = "Prints the file contents in the system console.\nAccess it with Window > Toggle System Console"

    @classmethod
    def poll(cls, context):
@@ -43,6 +48,7 @@ class PrintIfcFile(bpy.types.Operator):
 class PurgeIfcLinks(bpy.types.Operator):
    bl_idname = "bim.purge_ifc_links"
    bl_label = "Purge IFC Links"
+    bl_description = "Purge all definitions and references from the file.\nWarning : Cannot be undone."

    def execute(self, context):
        for obj in bpy.data.objects:
@@ -96,7 +102,8 @@ class ProfileImportIFC(bpy.types.Operator):

 class CreateAllShapes(bpy.types.Operator):
    bl_idname = "bim.create_all_shapes"
-    bl_label = "Create All Shapes"
+    bl_label = "Test All Shapes"
+    bl_description = "Look for errors in all the shapes contained in the file"

    @classmethod
    def poll(cls, context):
@@ -126,7 +133,7 @@ class CreateAllShapes(bpy.types.Operator):
            except:
                failures.append(element)
                print("***** FAILURE *****")
-        print("Failures:")
+        print(f"Failures: {len(failures)}")
        for failure in failures:
            print(failure)
        return {"FINISHED"}
@@ -135,6 +142,7 @@ class CreateAllShapes(bpy.types.Operator):
 class CreateShapeFromStepId(bpy.types.Operator):
    bl_idname = "bim.create_shape_from_step_id"
    bl_label = "Create Shape From STEP ID"
+    bl_description = "Recreate a mesh object from a STEP ID"
    bl_options = {"REGISTER", "UNDO"}
    should_include_curves: bpy.props.BoolProperty()

@@ -154,9 +162,12 @@ class CreateShapeFromStepId(bpy.types.Operator):
        if self.should_include_curves:
            settings.set(settings.INCLUDE_CURVES, True)
        shape = ifcopenshell.geom.create_shape(settings, element)
-        ifc_importer = import_ifc.IfcImporter(self.ifc_import_settings)
-        ifc_importer.file = self.file
-        mesh = ifc_importer.create_mesh(element, shape)
+        if shape:
+            ifc_importer = import_ifc.IfcImporter(self.ifc_import_settings)
+            ifc_importer.file = self.file
+            mesh = ifc_importer.create_mesh(element, shape)
+        else:
+            mesh = None
        obj = bpy.data.objects.new("Debug", mesh)
        context.scene.collection.objects.link(obj)
        return {"FINISHED"}
@@ -165,20 +176,37 @@ class CreateShapeFromStepId(bpy.types.Operator):
 class SelectHighPolygonMeshes(bpy.types.Operator):
    bl_idname = "bim.select_high_polygon_meshes"
    bl_label = "Select High Polygon Meshes"
+    bl_description = "Select objects containing more polygons than the specified number"
    bl_options = {"REGISTER", "UNDO"}
+    threshold: bpy.props.IntProperty()

    def execute(self, context):
-        [
-            o.select_set(True)
-            for o in context.view_layer.objects
-            if o.type == "MESH" and len(o.data.polygons) > context.scene.BIMDebugProperties.number_of_polygons
-        ]
+        for obj in context.view_layer.objects:
+            if obj.type == "MESH" and len(obj.data.polygons) > self.threshold:
+                obj.select_set(True)
+        return {"FINISHED"}
+
+
+class SelectHighestPolygonMeshes(bpy.types.Operator):
+    bl_idname = "bim.select_highest_polygon_meshes"
+    bl_label = "Select Highest Polygon Meshes"
+    bl_description = "Select objects with a number of polygons superior to the specified percentile"
+    bl_options = {"REGISTER", "UNDO"}
+    percentile: bpy.props.IntProperty()
+
+    def execute(self, context):
+        objects = [obj for obj in context.view_layer.objects if obj.type == "MESH"]
+        if objects:
+            percentile = len(max(objects, key=lambda o: len(o.data.polygons)).data.polygons) * self.percentile / 100
+            print(f"Selected all Meshes with more than {int(percentile)} polygons")
+            [obj.select_set(True) for obj in objects if len(obj.data.polygons) > percentile]
        return {"FINISHED"}


 class RewindInspector(bpy.types.Operator):
    bl_idname = "bim.rewind_inspector"
    bl_label = "Rewind Inspector"
+    bl_description = "Rewind the Inspector to the previously inspected element"

    def execute(self, context):
        props = context.scene.BIMDebugProperties
@@ -195,6 +223,7 @@ class RewindInspector(bpy.types.Operator):
 class InspectFromStepId(bpy.types.Operator):
    bl_idname = "bim.inspect_from_step_id"
    bl_label = "Inspect From STEP ID"
+    bl_description = "Inspect the attributes and references by looking up the specified STEP ID"
    step_id: bpy.props.IntProperty()

    @classmethod
@@ -245,12 +274,21 @@ class InspectFromStepId(bpy.types.Operator):
 class InspectFromObject(bpy.types.Operator):
    bl_idname = "bim.inspect_from_object"
    bl_label = "Inspect From Object"
+    bl_description = "Inspect the Active Object's attributes and references"
+
+    @classmethod
+    def poll(cls, context):
+        if not context.active_object:
+            if bpy.app.version >= (3, 0, 0):
+                cls.poll_message_set("No Active Object")
+        elif not context.active_object.BIMObjectProperties.ifc_definition_id:
+            if bpy.app.version >= (3, 0, 0):
+                cls.poll_message_set("Active Object doesn't have an IFC definition")
+        else:
+            return True

    def execute(self, context):
-        ifc_definition_id = context.active_object.BIMObjectProperties.ifc_definition_id
-        if not ifc_definition_id:
-            return {"FINISHED"}
-        bpy.ops.bim.inspect_from_step_id(step_id=ifc_definition_id)
+        bpy.ops.bim.inspect_from_step_id(step_id=context.active_object.BIMObjectProperties.ifc_definition_id)
        return {"FINISHED"}


@@ -262,3 +300,40 @@ class PrintObjectPlacement(bpy.types.Operator):
    def execute(self, context):
        print(ifcopenshell.util.placement.get_local_placement(IfcStore.get_file().by_id(self.step_id)))
        return {"FINISHED"}
+
+
+class ParseExpress(bpy.types.Operator):
+    bl_idname = "bim.parse_express"
+    bl_label = "Parse Express"
+
+    def execute(self, context):
+        core.parse_express(tool.Debug, context.scene.BIMDebugProperties.express_file)
+        blenderbim.bim.handler.refresh_ui_data()
+        return {"FINISHED"}
+
+
+class SelectExpressFile(bpy.types.Operator):
+    bl_idname = "bim.select_express_file"
+    bl_label = "Select Express File"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Select an IFC EXPRESS definition"
+    filepath: bpy.props.StringProperty(subtype="FILE_PATH")
+    filter_glob: bpy.props.StringProperty(default="*.exp", options={"HIDDEN"})
+
+    def execute(self, context):
+        if os.path.exists(self.filepath) and "exp" in os.path.splitext(self.filepath)[1]:
+            context.scene.BIMDebugProperties.express_file = self.filepath
+        return {"FINISHED"}
+
+    def invoke(self, context, event):
+        context.window_manager.fileselect_add(self)
+        return {"RUNNING_MODAL"}
+
+
+class PurgeHdf5Cache(bpy.types.Operator):
+    bl_idname = "bim.purge_hdf5_cache"
+    bl_label = "Purge HDF5 Cache"
+
+    def execute(self, context):
+        core.purge_hdf5_cache(tool.Debug)
+        return {"FINISHED"}
@@ -33,8 +33,10 @@ from bpy.props import (
 class BIMDebugProperties(PropertyGroup):
    step_id: IntProperty(name="STEP ID")
    number_of_polygons: IntProperty(name="Number of Polygons", min=0)
-    active_step_id: IntProperty(name="STEP ID")
+    percentile_of_polygons: IntProperty(name="Percentile of Polygons", min=0, max=100, default=90, subtype="PERCENTAGE")
+    active_step_id: IntProperty(name="STEP ID", default=1, soft_min=1)
    step_id_breadcrumb: CollectionProperty(name="STEP ID Breadcrumb", type=StrProperty)
    attributes: CollectionProperty(name="Attributes", type=Attribute)
    inverse_attributes: CollectionProperty(name="Inverse Attributes", type=Attribute)
    inverse_references: CollectionProperty(name="Inverse References", type=Attribute)
+    express_file: StringProperty(name="Express File")
@@ -27,6 +27,7 @@ class BIM_PT_debug(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_quality_control"

    def draw(self, context):
        layout = self.layout
@@ -38,9 +39,17 @@ class BIM_PT_debug(Panel):
        row.operator("bim.validate_ifc_file", icon="CHECKMARK", text="")
        row.operator("bim.select_ifc_file", icon="FILE_FOLDER", text="")

+        row = self.layout.row(align=True)
+        row.prop(props, "express_file", text="")
+        row.operator("bim.parse_express", icon="IMPORT", text="")
+        row.operator("bim.select_express_file", icon="FILE_FOLDER", text="")
+
        row = layout.row()
        row.operator("bim.print_ifc_file")

+        row = layout.row()
+        row.operator("bim.purge_hdf5_cache")
+
        row = layout.row()
        row.operator("bim.purge_ifc_links")

@@ -56,8 +65,13 @@ class BIM_PT_debug(Panel):
        row.prop(props, "step_id", text="")

        row = layout.split(factor=0.7, align=True)
-        row.operator("bim.select_high_polygon_meshes")
+        row.operator("bim.select_high_polygon_meshes").threshold = context.scene.BIMDebugProperties.number_of_polygons
        row.prop(props, "number_of_polygons", text="")
+        row = layout.split(factor=0.7, align=True)
+        row.operator(
+            "bim.select_highest_polygon_meshes"
+        ).percentile = context.scene.BIMDebugProperties.percentile_of_polygons
+        row.prop(props, "percentile_of_polygons", text="")

        layout.label(text="Inspector:")

@@ -0,0 +1,58 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+# ############################################################################ #
+
+# Hey there! Welcome to the BlenderBIM Add-on code. Please feel free to reach
+# out if you have any questions or need further guidance. Happy hacking!
+
+# ############################################################################ #
+
+# Every module has a __init__.py file to load all of its classes. Every
+# operation, property, and interface needs to be registered with the Blender
+# system when the add-on loads. This is where it happens.
+
+import bpy
+from . import ui, prop, operator
+
+# You'll need to provide a list of every one of your classes here. If you forget
+# to specify your class, it won't load and you won't be able to use that
+# operator, property, or interface.
+classes = (
+    operator.DemonstrateHelloWorld,
+    operator.DemonstrateRenameProject,
+    prop.BIMDemoProperties,
+    ui.BIM_PT_demo,
+)
+
+
+# When the add-on loads, this register function is called. This allows you to
+# perform additional tasks during startup. If you need to store custom
+# properties, this is where you tell Blender where they are going to be stored.
+# You might see more advanced registrations happening in other modules.
+def register():
+    # Properties are usually stored on bpy.types.Scene when they are something
+    # that affects everything in the project, or bpy.types.Object when they
+    # affect a single BIM element.
+    bpy.types.Scene.BIMDemoProperties = bpy.props.PointerProperty(type=prop.BIMDemoProperties)
+
+
+# When someone disables the add-on, we need to unload everything we loaded. This
+# does the reverse of the register function.
+def unregister():
+    del bpy.types.Scene.BIMDemoProperties
@@ -0,0 +1,78 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+# ############################################################################ #
+
+# Hey there! Welcome to the BlenderBIM Add-on code. Please feel free to reach
+# out if you have any questions or need further guidance. Happy hacking!
+
+# ############################################################################ #
+
+# Every module has a data.py file to load data for its interface panels to
+# display. When a panel needs to show information that doesn't come from a
+# Blender property, it gets that data from one of these classes. This separation
+# of "fetching data" and "displaying data" is a common concept that makes UI
+# code much simpler, more efficient, and less error-prone to refresh data.
+
+import blenderbim.tool as tool
+
+
+# All data must have a refresh function. The refresh function simply sets all
+# data class to be not yet loaded. So the next time the interface is drawn to
+# the user, it will force the data to be reloaded.
+def refresh():
+    # When you define your own data classes, just add to this list!
+    DemoData.is_loaded = False
+
+
+# This is a sample data class. It correlates to a single interface panel. Panels
+# should not share data classes. This makes it easy to write your interface
+# without having your code mixed in with other parts of the interface. As a
+# convention, the class is named the same name as the panel.
+class DemoData:
+    # All data classes must have two variables. One to store all the data it has
+    # loaded and another to store the load state.
+    data = {}
+    is_loaded = False
+
+    # Every data class must have a load function. This lets us load data in a
+    # predictable manner.
+    @classmethod
+    def load(cls):
+        # The load function always has two responsibilities: populate the data,
+        # and set is_loaded to true.
+        cls.data = {
+            "has_project": cls.has_project(),
+            "project_name": cls.project_name(),
+        }
+        cls.is_loaded = True
+
+    @classmethod
+    def has_project(cls):
+        # Here, we check whether or not there is an active IFC project in our
+        # Blender session.
+        return bool(tool.Ifc.get())
+
+    @classmethod
+    def project_name(cls):
+        # Imagine how messy our UI code would be if all of this was mixed in
+        # with our layout code. Here, it's isolated and testable, and the UX
+        # becomes easier to maintain and change.
+        ifc = tool.Ifc.get()
+        if ifc:
+            return ifc.by_type("IfcProject")[0].Name or "Unnamed"
@@ -0,0 +1,79 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+# ############################################################################ #
+
+# Hey there! Welcome to the BlenderBIM Add-on code. Please feel free to reach
+# out if you have any questions or need further guidance. Happy hacking!
+
+# ############################################################################ #
+
+# Every module has an operator.py file to define all of the buttons that a user
+# can click on from the Blender interface. Blender calls these buttons
+# "Operators", since they correlate to a single user operation.
+
+import bpy
+import blenderbim.tool as tool
+import blenderbim.core.demo as core
+import blenderbim.bim.handler
+
+
+# Each button correlates to a class like the one below. In this case, we're
+# creating a new button that will execute a hello world feature.
+class DemonstrateHelloWorld(bpy.types.Operator, tool.Ifc.Operator):
+    # Every operator has a unique ID. If you enable Python tooltips and hover
+    # over any button in the interface, you will see each button will run a
+    # function that uses this ID. For example, hovering over this button will
+    # show that the code it executes is "bpy.ops.bim.demonstrate_hello_world()"
+    bl_idname = "bim.demonstrate_hello_world"
+
+    # In the interface, this button will have the text "Print Hello World".
+    bl_label = "Print Hello World"
+
+    # This code means that the user can undo or redo after pressing the button.
+    bl_options = {"REGISTER", "UNDO"}
+
+    # When hovering over the button, this helpful description will be shown.
+    bl_description = "Prints the text 'Hello World'"
+
+    # When the button is pressed, this _execute() function will run.
+    def _execute(self, context):
+        # Every operator should do one thing only: execute a core function. In
+        # order to execute a core function, the operator's responsibility is to
+        # pass in all of the inputs the core needs to do its job.
+
+        # A core function simply tells tools what to do, so a core function will
+        # always need at least one tool as an input.
+        core.demonstrate_hello_world(tool.Demo)
+
+
+# This class, just like the one above, will correlate to another button in the
+# interface. It has a different ID and a different label.
+class DemonstrateRenameProject(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.demonstrate_rename_project"
+    bl_label = "Rename IFC Project"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Renames your IFC project name and prints the name"
+
+    def _execute(self, context):
+        # This core function requires three inputs: two tools, and a name
+        # string. In this case, the name is taken from some custom Blender
+        # properties. Generally, the inputs to the core function will come from
+        # properties (such as an input field) or data from the scene (like the
+        # actively selected object).
+        core.demonstrate_rename_project(tool.Ifc, tool.Demo, name=bpy.context.scene.BIMDemoProperties.name)
@@ -0,0 +1,61 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+# ############################################################################ #
+
+# Hey there! Welcome to the BlenderBIM Add-on code. Please feel free to reach
+# out if you have any questions or need further guidance. Happy hacking!
+
+# ############################################################################ #
+
+# Every module has a prop.py file to define Blender properties. Any time you
+# want an interface widget like an input field, dropdown, checkbox, or number
+# slider, you need a Blender property to store that widget's data. If you want
+# to store data that will affect the Blender interface, you also need a
+# property. Properties are stored in the .blend file, so when your user closes
+# their Blender session, and reopens it, things are how they left it.
+
+import bpy
+from bpy.types import PropertyGroup
+
+# Properties have many different data types. We won't use all of them in this
+# demo module, but this is a list for your reference.
+from bpy.props import (
+    PointerProperty,
+    StringProperty,
+    EnumProperty,
+    BoolProperty,
+    IntProperty,
+    FloatProperty,
+    FloatVectorProperty,
+    CollectionProperty,
+)
+
+
+# All properties must belong in a property group. Usually, you'd have a group
+# named after your module.
+class BIMDemoProperties(PropertyGroup):
+    # This first property is a string. This means that in the interface, it will
+    # represent a text input field. We can give it a name and a default value.
+    # The name will be the label shown next to the input field in the interface.
+    name: StringProperty(name="Name", default="New Project Name")
+    # Not all properties need to be shown using their equivalent input widget.
+    # In this case, we can store a message string, but we will never show it as
+    # an input text field in the ui.py.
+    message: StringProperty(name="Message")
+    show_hints: BoolProperty(name="Show Hints", default=False)
@@ -0,0 +1,131 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+# ############################################################################ #
+
+# Hey there! Welcome to the BlenderBIM Add-on code. Please feel free to reach
+# out if you have any questions or need further guidance. Happy hacking!
+
+# ############################################################################ #
+
+# Every module has a ui.py file to define its interface. Interfaces describe how
+# panels, buttons, labels, and input fields are laid out.
+
+import bpy
+from blenderbim.bim.module.demo.data import DemoData
+
+# Every panel in the interface correlates to one of these classes. If you enable
+# the "Developer Extras" option in Blender, then you can actually right click on
+# any panel in Blender, and click "Edit Source". This will bring you to a ui.py
+# file like this one where you can see this code. Pretty neat!
+class BIM_PT_demo(bpy.types.Panel):
+    # Every panel has a title.
+    bl_label = "BlenderBIM Demo"
+
+    # Every panel must have an ID. It must be unique. For example, you may want
+    # to later reference the panel (such as if you want to create a nested
+    # subpanel).
+    bl_idname = "BIM_PT_demo"
+
+    # This tells the panel to appear in the properties section (in the bottom
+    # right by default) of the Blender interface.
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+
+    # This tells the panel to appear in the "scene" tab of the properties panel.
+    bl_context = "scene"
+
+    # Every panel has a draw function. This draws all the layout of the panel,
+    # including all of its labels, buttons, and so on. Note that if the panel is
+    # hidden, this draw function will not be called.
+    def draw(self, context):
+        # Before drawing any content, the panel must load any dynamic variables
+        # that it will show. Most panels have dynamic content, which display
+        # changing data from your BIM model. You must load that data first. The
+        # two lines are always the same, "if not loaded, then load".
+        if not DemoData.is_loaded:
+            # Each panel should have its own data class that it loads data from.
+            # Note that we only load data if it hasn't already been loaded.
+            # This is because interface panels are drawn continuously. This
+            # draw() function will be called every time you scroll or move your
+            # mouse over it. Loading data is slow, so we only refresh data when
+            # we have to.
+            DemoData.load()
+
+        # Interface panels often show properties. For convenience, define where
+        # the properties are stored for the module.
+        self.props = context.scene.BIMDemoProperties
+
+        # This defines a new "row" in our layout. When a new row is defined, the
+        # things on that row, like buttons, labels, and input fields, show on a
+        # new line.
+        row = self.layout.row()
+        # This is the simplest interface element - a label placed in our row.
+        # If you enable the "Icon Viewer" add-on, you can view a list of
+        # Blender's built-in icons to choose from in the Blender text editor's
+        # side panel.
+        row.label(text="This is a demo panel", icon="INFO")
+
+        # Our interface can contain simple logic. For example, if we don't have
+        # an IFC project, show an error message and don't draw anything else.
+        # The ui.py should always have very simple logic. Details like how to
+        # determine whether we have a project is delegated to the data loader.
+        if not DemoData.data["has_project"]:
+            row = self.layout.row()
+            row.label(text="Load or create an IFC project first", icon="ERROR")
+            return
+
+        row = self.layout.row()
+        # When you want to show a button in the interface, you have to specify
+        # an operator. Operators are defined in operator.py. You reference an
+        # operator using its unique ID.
+        row.operator("bim.demonstrate_hello_world")
+
+        # Blender properties can be used to affect what your panel shows. Notice
+        # how the logic is very simple. Only use simple boolean predicates and
+        # loops in your layout. No complex logic should ever been seen in the
+        # interface code.
+        if self.props.message:
+            row = self.layout.row()
+            row.label(text=self.props.message)
+
+        row = self.layout.row(align=True)
+        row.label(text="Project Name")
+        # Sometimes you need data that doesn't come from Blender properties,
+        # like from your IFC model. In this case, just get some data from your
+        # data loader. For those familiar with how templating languages work,
+        # this is exactly the same.
+        row.label(text=DemoData.data["project_name"])
+
+        row = self.layout.row()
+        # We've seen how to show text labels and buttons using operators. What
+        # about text input fields, number sliders, dropdowns, checkboxes, and
+        # scrollable lists? The way Blender works is that you simply show a
+        # Blender property in your interface. The data type of that property
+        # determines which UI widget is shown. A text property will show a text
+        # field. A number property will show a number slider. An enum property
+        # will show a drop down. And so on. In this case, our name property is a
+        # text data type, so expect to see a text input field show up here.
+        row.prop(self.props, "name")
+        row = self.layout.row()
+        # Here's another button, referencing another operator.
+        row.operator("bim.demonstrate_rename_project")
+
+        if self.props.show_hints:
+            row = self.layout.row()
+            row.label(text="Name cannot be blank!")
@@ -27,6 +27,7 @@ class BIM_PT_diff(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_quality_control"

    def draw(self, context):
        layout = self.layout
@@ -20,35 +20,29 @@ import bpy
 from . import ui, prop, operator

 classes = (
-    operator.LoadInformation,
-    operator.LoadDocumentReferences,
-    operator.DisableDocumentEditingUI,
-    operator.EnableEditingDocument,
-    operator.DisableEditingDocument,
-    operator.AddInformation,
    operator.AddDocumentReference,
-    operator.EditInformation,
-    operator.EditDocumentReference,
-    operator.RemoveDocument,
-    operator.EnableAssigningDocument,
-    operator.DisableAssigningDocument,
+    operator.AddInformation,
    operator.AssignDocument,
+    operator.DisableDocumentEditingUI,
+    operator.DisableEditingDocument,
+    operator.EditDocument,
+    operator.EnableEditingDocument,
+    operator.LoadDocument,
+    operator.LoadParentDocument,
+    operator.LoadProjectDocuments,
+    operator.RemoveDocument,
    operator.UnassignDocument,
    prop.Document,
    prop.BIMDocumentProperties,
-    prop.BIMObjectDocumentProperties,
    ui.BIM_PT_documents,
    ui.BIM_PT_object_documents,
    ui.BIM_UL_documents,
-    ui.BIM_UL_object_documents,
 )


 def register():
    bpy.types.Scene.BIMDocumentProperties = bpy.props.PointerProperty(type=prop.BIMDocumentProperties)
-    bpy.types.Object.BIMObjectDocumentProperties = bpy.props.PointerProperty(type=prop.BIMObjectDocumentProperties)


 def unregister():
    del bpy.types.Scene.BIMDocumentProperties
-    del bpy.types.Object.BIMObjectDocumentProperties
@@ -0,0 +1,116 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+import bpy
+import ifcopenshell
+import ifcopenshell.util.schema
+import blenderbim.tool as tool
+
+
+def refresh():
+    DocumentData.is_loaded = False
+    ObjectDocumentData.is_loaded = False
+
+
+class DocumentData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {
+            "total_information": cls.total_information(),
+            "parent_document": cls.parent_document(),
+        }
+        cls.is_loaded = True
+
+    @classmethod
+    def total_information(cls):
+        return len(
+            [
+                rel
+                for rel in tool.Ifc.get().by_type("IfcProject")[0].HasAssociations or []
+                if rel.is_a("IfcRelAssociatesDocument") and rel.RelatingDocument.is_a("IfcDocumentInformation")
+            ]
+        )
+
+    @classmethod
+    def parent_document(cls):
+        props = bpy.context.scene.BIMDocumentProperties
+        if len(props.breadcrumbs):
+            parent = tool.Ifc.get().by_id(int(props.breadcrumbs[-1].name))
+            if tool.Ifc.get_schema() == "IFC2X3":
+                return str(parent.DocumentId)
+            return str(parent.Identification)
+        return ""
+
+
+class ObjectDocumentData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {
+            "documents": cls.documents(),
+        }
+        cls.is_loaded = True
+
+    @classmethod
+    def documents(cls):
+        results = []
+        element = tool.Ifc.get_entity(bpy.context.active_object)
+        if not element:
+            return results
+        for rel in getattr(element, "HasAssociations", []):
+            if rel.is_a("IfcRelAssociatesDocument"):
+                if not rel.RelatingDocument.is_a("IfcDocumentReference"):
+                    continue
+
+                name = rel.RelatingDocument.Name
+                if not name and rel.RelatingDocument.ReferencedDocument:
+                    name = rel.RelatingDocument.ReferencedDocument.Name
+
+                if tool.Ifc.get_schema() == "IFC2X3":
+                    identification = rel.RelatingDocument.ItemReference
+                    if not identification and rel.RelatingDocument.ReferencedDocument:
+                        identification = rel.RelatingDocument.ReferencedDocument.DocumentId
+                else:
+                    identification = rel.RelatingDocument.Identification
+                    if not identification and rel.RelatingDocument.ReferencedDocument:
+                        identification = rel.RelatingDocument.ReferencedDocument.Identification
+
+                location = rel.RelatingDocument.Location
+                if location is None and rel.RelatingDocument.ReferencedDocument:
+                    location = rel.RelatingDocument.ReferencedDocument.Location
+                if location:
+                    if not "://" in location:
+                        if not os.path.isabs(location):
+                            location = os.path.abspath(os.path.join(os.path.dirname(tool.Ifc.get_path()), location))
+                        location = "file://" + location
+
+                results.append(
+                    {
+                        "id": rel.RelatingDocument.id(),
+                        "identification": identification,
+                        "name": name,
+                        "location": location,
+                    }
+                )
+        return results
@@ -1,5 +1,5 @@
 # BlenderBIM Add-on - OpenBIM Blender Add-on
-# Copyright (C) 2020, 2021 Dion Moult <dion@thinkmoult.com>
+# Copyright (C) 2020, 2021, 2022 Dion Moult <dion@thinkmoult.com>
 #
 # This file is part of BlenderBIM Add-on.
 #
@@ -20,303 +20,133 @@ import bpy
 import json
 import ifcopenshell.api
 import ifcopenshell.util.attribute
+import blenderbim.tool as tool
+import blenderbim.core.document as core
 from blenderbim.bim.ifc import IfcStore
 from ifcopenshell.api.document.data import Data


-class LoadInformation(bpy.types.Operator):
-    bl_idname = "bim.load_information"
-    bl_label = "Load Information"
+class LoadProjectDocuments(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.load_project_documents"
+    bl_label = "Load Project Documents"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        self.file = IfcStore.get_file()
-        props = context.scene.BIMDocumentProperties
-        props.documents.clear()
-        for information_id, information in Data.information.items():
-            new = props.documents.add()
-            new.name = information["Name"] or "Unnamed"
-            if self.file.schema == "IFC2X3":
-                new.identification = information["DocumentId"] or "*"
-            else:
-                new.identification = information["Identification"] or "*"
-            new.ifc_definition_id = information_id
-        props.is_editing = "information"
-        bpy.ops.bim.disable_editing_document()
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.load_project_documents(tool.Document)


-class LoadDocumentReferences(bpy.types.Operator):
-    bl_idname = "bim.load_document_references"
-    bl_label = "Load Document References"
+class LoadDocument(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.load_document"
+    bl_label = "Load Document"
+    bl_options = {"REGISTER", "UNDO"}
+    document: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.load_document(tool.Document, document=tool.Ifc.get().by_id(self.document))
+
+
+class LoadParentDocument(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.load_parent_document"
+    bl_label = "Load Parent Document"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        self.file = IfcStore.get_file()
-        props = context.scene.BIMDocumentProperties
-        props.documents.clear()
-        for reference_id, reference in Data.references.items():
-            new = props.documents.add()
-            new.name = reference["Name"] or "Unnamed"
-            if self.file.schema == "IFC2X3":
-                new.identification = reference["ItemReference"] or "*"
-            else:
-                new.identification = reference["Identification"] or "*"
-            new.ifc_definition_id = reference_id
-        props.is_editing = "reference"
-        bpy.ops.bim.disable_editing_document()
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.load_parent_document(tool.Document)


-class DisableDocumentEditingUI(bpy.types.Operator):
+class DisableDocumentEditingUI(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.disable_document_editing_ui"
    bl_label = "Disable Document Editing UI"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        context.scene.BIMDocumentProperties.is_editing = ""
-        bpy.ops.bim.disable_editing_document()
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.disable_document_editing_ui(tool.Document)


-class EnableEditingDocument(bpy.types.Operator):
+class EnableEditingDocument(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.enable_editing_document"
    bl_label = "Enable Editing Document"
    bl_options = {"REGISTER", "UNDO"}
    document: bpy.props.IntProperty()

-    def execute(self, context):
-        props = context.scene.BIMDocumentProperties
-        props.document_attributes.clear()
-
-        if props.is_editing == "information":
-            data = Data.information[self.document]
-            ifc_class = "IfcDocumentInformation"
-        elif props.is_editing == "reference":
-            data = Data.references[self.document]
-            ifc_class = "IfcDocumentReference"
-
-        for attribute in IfcStore.get_schema().declaration_by_name(ifc_class).all_attributes():
-            data_type = ifcopenshell.util.attribute.get_primitive_type(attribute)
-            if data_type == "entity":
-                continue
-            new = props.document_attributes.add()
-            new.name = attribute.name()
-            new.is_null = data[attribute.name()] is None
-            new.is_optional = attribute.optional()
-            new.data_type = data_type
-            if data_type == "string":
-                new.string_value = "" if new.is_null else data[attribute.name()]
-            elif data_type == "enum":
-                new.enum_items = json.dumps(ifcopenshell.util.attribute.get_enum_items(attribute))
-                if data[attribute.name()]:
-                    new.enum_value = data[attribute.name()]
-        props.active_document_id = self.document
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.enable_editing_document(tool.Document, document=tool.Ifc.get().by_id(self.document))


-class DisableEditingDocument(bpy.types.Operator):
+class DisableEditingDocument(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.disable_editing_document"
    bl_label = "Disable Editing Document"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        context.scene.BIMDocumentProperties.active_document_id = 0
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.disable_editing_document(tool.Document)


-class AddInformation(bpy.types.Operator):
+class AddInformation(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.add_information"
    bl_label = "Add Information"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        result = ifcopenshell.api.run("document.add_information", IfcStore.get_file())
-        Data.load(IfcStore.get_file())
-        bpy.ops.bim.load_information()
-        bpy.ops.bim.enable_editing_document(document=result.id())
-        return {"FINISHED"}
+        core.add_information(tool.Ifc, tool.Document)


-class AddDocumentReference(bpy.types.Operator):
+class AddDocumentReference(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.add_document_reference"
    bl_label = "Add Document Reference"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        result = ifcopenshell.api.run("document.add_reference", IfcStore.get_file())
-        Data.load(IfcStore.get_file())
-        bpy.ops.bim.load_document_references()
-        bpy.ops.bim.enable_editing_document(document=result.id())
-        return {"FINISHED"}
+        core.add_reference(tool.Ifc, tool.Document)


-class EditInformation(bpy.types.Operator):
-    bl_idname = "bim.edit_information"
+class EditDocument(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.edit_document"
    bl_label = "Edit Information"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
        props = context.scene.BIMDocumentProperties
-        attributes = {}
-        for attribute in props.document_attributes:
-            if attribute.is_null:
-                attributes[attribute.name] = None
-            elif attribute.enum_items:
-                attributes[attribute.name] = attribute.enum_value
-            else:
-                attributes[attribute.name] = attribute.string_value
-        self.file = IfcStore.get_file()
-        ifcopenshell.api.run(
-            "document.edit_information",
-            self.file,
-            **{"information": self.file.by_id(props.active_document_id), "attributes": attributes}
-        )
-        Data.load(IfcStore.get_file())
-        bpy.ops.bim.load_information()
-        return {"FINISHED"}
+        core.edit_document(tool.Ifc, tool.Document, document=tool.Ifc.get().by_id(props.active_document_id))


-class EditDocumentReference(bpy.types.Operator):
-    bl_idname = "bim.edit_document_reference"
-    bl_label = "Edit Document Reference"
-    bl_options = {"REGISTER", "UNDO"}
-
-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
-    def _execute(self, context):
-        props = context.scene.BIMDocumentProperties
-        attributes = {}
-        for attribute in props.document_attributes:
-            if attribute.is_null:
-                attributes[attribute.name] = None
-            else:
-                attributes[attribute.name] = attribute.string_value
-        self.file = IfcStore.get_file()
-        ifcopenshell.api.run(
-            "document.edit_reference",
-            self.file,
-            **{"reference": self.file.by_id(props.active_document_id), "attributes": attributes}
-        )
-        Data.load(IfcStore.get_file())
-        bpy.ops.bim.load_document_references()
-        return {"FINISHED"}
-
-
-class RemoveDocument(bpy.types.Operator):
+class RemoveDocument(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.remove_document"
    bl_label = "Remove Document"
    bl_options = {"REGISTER", "UNDO"}
    document: bpy.props.IntProperty()

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        props = context.scene.BIMDocumentProperties
-        self.file = IfcStore.get_file()
-        ifcopenshell.api.run("document.remove_document", self.file, **{"document": self.file.by_id(self.document)})
-        Data.load(IfcStore.get_file())
-        if props.is_editing == "information":
-            bpy.ops.bim.load_information()
-        elif props.is_editing == "reference":
-            bpy.ops.bim.load_document_references()
-        return {"FINISHED"}
+        core.remove_document(tool.Ifc, tool.Document, document=tool.Ifc.get().by_id(self.document))


-class EnableAssigningDocument(bpy.types.Operator):
-    bl_idname = "bim.enable_assigning_document"
-    bl_label = "Enable Assigning Document"
-    bl_options = {"REGISTER", "UNDO"}
-    obj: bpy.props.StringProperty()
-
-    def execute(self, context):
-        obj = bpy.data.objects.get(self.obj) if self.obj else context.active_object
-        props = obj.BIMObjectDocumentProperties
-        if props.available_document_types == "IfcDocumentInformation":
-            bpy.ops.bim.load_information()
-        elif props.available_document_types == "IfcDocumentReference":
-            bpy.ops.bim.load_document_references()
-        props.is_adding = props.available_document_types
-        return {"FINISHED"}
-
-
-class DisableAssigningDocument(bpy.types.Operator):
-    bl_idname = "bim.disable_assigning_document"
-    bl_label = "Disable Assigning Document"
-    bl_options = {"REGISTER", "UNDO"}
-    obj: bpy.props.StringProperty()
-
-    def execute(self, context):
-        obj = bpy.data.objects.get(self.obj) if self.obj else context.active_object
-        props = obj.BIMObjectDocumentProperties
-        props.is_adding = ""
-        return {"FINISHED"}
-
-
-class AssignDocument(bpy.types.Operator):
+class AssignDocument(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.assign_document"
    bl_label = "Assign Document"
    bl_options = {"REGISTER", "UNDO"}
    obj: bpy.props.StringProperty()
    document: bpy.props.IntProperty()

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        self.file = IfcStore.get_file()
+        document = tool.Ifc.get().by_id(self.document)
        objs = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
        for obj in objs:
-            obj_id = obj.BIMObjectProperties.ifc_definition_id
-            if not obj_id:
-                continue
-            ifcopenshell.api.run(
-                "document.assign_document",
-                self.file,
-                **{
-                    "product": self.file.by_id(obj_id),
-                    "document": self.file.by_id(self.document),
-                }
-            )
-            Data.load(self.file, obj_id)
-        return {"FINISHED"}
+            element = tool.Ifc.get_entity(obj)
+            if element:
+                core.assign_document(tool.Ifc, product=element, document=document)


-class UnassignDocument(bpy.types.Operator):
+class UnassignDocument(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.unassign_document"
    bl_label = "Unassign Document"
    bl_options = {"REGISTER", "UNDO"}
    obj: bpy.props.StringProperty()
    document: bpy.props.IntProperty()

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        self.file = IfcStore.get_file()
+        document = tool.Ifc.get().by_id(self.document)
        objs = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
        for obj in objs:
-            obj_id = obj.BIMObjectProperties.ifc_definition_id
-            if not obj_id:
-                continue
-            ifcopenshell.api.run(
-                "document.unassign_document",
-                self.file,
-                **{
-                    "product": self.file.by_id(obj_id),
-                    "document": self.file.by_id(self.document),
-                }
-            )
-            Data.load(self.file, obj_id)
-        return {"FINISHED"}
+            element = tool.Ifc.get_entity(obj)
+            if element:
+                core.unassign_document(tool.Ifc, product=element, document=document)
@@ -34,6 +34,7 @@ from bpy.props import (
 class Document(PropertyGroup):
    name: StringProperty(name="Name")
    identification: StringProperty(name="Identification")
+    is_information: BoolProperty(name="Is Information")
    ifc_definition_id: IntProperty(name="IFC Definition ID")


@@ -41,12 +42,6 @@ class BIMDocumentProperties(PropertyGroup):
    document_attributes: CollectionProperty(name="Document Attributes", type=Attribute)
    active_document_id: IntProperty(name="Active Document Id")
    documents: CollectionProperty(name="Documents", type=Document)
+    breadcrumbs: CollectionProperty(name="Breadcrumbs", type=StrProperty)
    active_document_index: IntProperty(name="Active Document Index")
-    is_editing: StringProperty(name="Is Editing")
-
-
-class BIMObjectDocumentProperties(PropertyGroup):
-    is_adding: StringProperty(name="Is Adding")
-    available_document_types: EnumProperty(
-        items=[(d, d, "") for d in ["IfcDocumentInformation", "IfcDocumentReference"]], name="Available Document Types"
-    )
+    is_editing: BoolProperty(name="Is Editing", default=False)
@@ -19,7 +19,7 @@
 from bpy.types import Panel, UIList
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.helper import draw_attributes
-from ifcopenshell.api.document.data import Data
+from blenderbim.bim.module.document.data import DocumentData, ObjectDocumentData


 class BIM_PT_documents(Panel):
@@ -29,45 +29,50 @@ class BIM_PT_documents(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_project_setup"

    @classmethod
    def poll(cls, context):
        return IfcStore.get_file()

    def draw(self, context):
-        if not Data.is_loaded:
-            Data.load(IfcStore.get_file())
+        if not DocumentData.is_loaded:
+            DocumentData.load()

        self.props = context.scene.BIMDocumentProperties

-        if not self.props.is_editing or self.props.is_editing == "information":
-            row = self.layout.row(align=True)
-            row.label(text="{} Documents Found".format(len(Data.information)), icon="FILE")
-            if self.props.is_editing == "information":
-                row.operator("bim.add_information", text="", icon="ADD")
-                row.operator("bim.disable_document_editing_ui", text="", icon="CANCEL")
-            else:
-                row.operator("bim.load_information", text="", icon="IMPORT")
-
-        if not self.props.is_editing or self.props.is_editing == "reference":
-            row = self.layout.row(align=True)
-            row.label(text="{} References Found".format(len(Data.references)), icon="FILE_HIDDEN")
-            if self.props.is_editing == "reference":
-                row.operator("bim.add_document_reference", text="", icon="ADD")
-                row.operator("bim.disable_document_editing_ui", text="", icon="CANCEL")
-            else:
-                row.operator("bim.load_document_references", text="", icon="IMPORT")
-
+        row = self.layout.row(align=True)
+        row.label(text="{} Documents Found".format(DocumentData.data["total_information"]), icon="FILE")
        if self.props.is_editing:
-            self.layout.template_list(
-                "BIM_UL_documents", "", self.props, "documents", self.props, "active_document_index"
-            )
+            row.operator("bim.disable_document_editing_ui", text="", icon="CANCEL")
+        else:
+            row.operator("bim.load_project_documents", text="", icon="IMPORT")
+
+        if not self.props.is_editing:
+            return
+
+        row = self.layout.row(align=True)
+        if self.props.breadcrumbs:
+            row.operator("bim.load_parent_document", text="", icon="FRAME_PREV")
+            row.label(text=DocumentData.data["parent_document"])
+        else:
+            row.alignment = "RIGHT"
+        row.operator("bim.add_information", text="", icon="ADD")
+        if self.props.breadcrumbs:
+            row.operator("bim.add_document_reference", text="", icon="FILE_HIDDEN")

        if self.props.active_document_id:
-            self.draw_editable_ui(context)
+            row.operator("bim.edit_document", text="", icon="CHECKMARK")
+            row.operator("bim.disable_editing_document", text="", icon="CANCEL")
+        elif self.props.documents and self.props.active_document_index < len(self.props.documents):
+            ifc_definition_id = self.props.documents[self.props.active_document_index].ifc_definition_id
+            row.operator("bim.enable_editing_document", text="", icon="GREASEPENCIL").document = ifc_definition_id
+            row.operator("bim.remove_document", text="", icon="X").document = ifc_definition_id

-    def draw_editable_ui(self, context):
-        draw_attributes(self.props.document_attributes, self.layout)
+        self.layout.template_list("BIM_UL_documents", "", self.props, "documents", self.props, "active_document_index")
+
+        if self.props.active_document_id:
+            draw_attributes(self.props.document_attributes, self.layout)


 class BIM_PT_object_documents(Panel):
@@ -77,6 +82,7 @@ class BIM_PT_object_documents(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_misc_object"

    @classmethod
    def poll(cls, context):
@@ -87,88 +93,64 @@ class BIM_PT_object_documents(Panel):
        return bool(context.active_object.BIMObjectProperties.ifc_definition_id)

    def draw(self, context):
+        if not ObjectDocumentData.is_loaded:
+            ObjectDocumentData.load()
+
        obj = context.active_object
        self.oprops = obj.BIMObjectProperties
-        self.sprops = context.scene.BIMDocumentProperties
-        self.props = obj.BIMObjectDocumentProperties
+        self.props = context.scene.BIMDocumentProperties
        self.file = IfcStore.get_file()
-        if not Data.is_loaded:
-            Data.load(IfcStore.get_file())
-        if self.oprops.ifc_definition_id not in Data.products:
-            Data.load(IfcStore.get_file(), self.oprops.ifc_definition_id)

        self.draw_add_ui()

-        document_ids = Data.products[self.oprops.ifc_definition_id]
-
-        if not document_ids:
+        if not ObjectDocumentData.data["documents"]:
            row = self.layout.row(align=True)
            row.label(text="No Documents", icon="FILE")

-        for document_id in document_ids:
-            try:
-                document = Data.information[document_id]
-                document_type = "IfcDocumentInformation"
-                icon = "FILE"
-            except:
-                document = Data.references[document_id]
-                document_type = "IfcDocumentReference"
-                icon = "FILE_HIDDEN"
+        for document in ObjectDocumentData.data["documents"]:
            row = self.layout.row(align=True)
-            if self.file.schema == "IFC2X3":
-                if document_type == "IfcDocumentInformation":
-                    row.label(text=document.get("DocumentId") or "*", icon=icon)
-                elif document_type == "IfcDocumentReference":
-                    row.label(text=document.get("ItemReference") or "*", icon=icon)
-            else:
-                row.label(text=document.get("Identification") or "*", icon=icon)
-            row.label(text=document.get("Name") or "Unnamed")
-            row.operator("bim.unassign_document", text="", icon="X").document = document_id
+            row.label(text=document["identification"] or "*", icon="FILE")
+            row.label(text=document["name"] or "Unnamed")
+            if document["location"]:
+                row.operator("bim.open_uri", icon="URL", text="").uri = document["location"]
+            row.operator("bim.unassign_document", text="", icon="X").document = document["id"]

    def draw_add_ui(self):
-        if self.props.is_adding:
+        if not self.props.is_editing:
            row = self.layout.row(align=True)
-            icon = "FILE" if self.props.is_adding == "IfcDocumentInformation" else "FILE_HIDDEN"
-            row.label(text="Adding {}".format(self.props.is_adding), icon=icon)
-            row.operator("bim.disable_assigning_document", text="", icon="CANCEL")
-            self.layout.template_list(
-                "BIM_UL_object_documents",
-                "",
-                self.sprops,
-                "documents",
-                self.sprops,
-                "active_document_index",
-            )
+            row.operator("bim.load_project_documents", text="Assign Document References", icon="ADD")
+            return
+
+        row = self.layout.row(align=True)
+        if self.props.breadcrumbs:
+            row.operator("bim.load_parent_document", text="", icon="FRAME_PREV")
+            row.label(text=DocumentData.data["parent_document"])
        else:
-            row = self.layout.row(align=True)
-            row.prop(self.props, "available_document_types", text="")
-            row.operator("bim.enable_assigning_document", text="", icon="ADD")
+            row.alignment = "RIGHT"
+
+        if self.props.documents and self.props.active_document_index < len(self.props.documents):
+            document = self.props.documents[self.props.active_document_index]
+            if not document.is_information:
+                row.operator("bim.assign_document", text="", icon="ADD").document = document.ifc_definition_id
+        row.operator("bim.disable_document_editing_ui", text="", icon="CANCEL")
+
+        self.layout.template_list("BIM_UL_documents", "", self.props, "documents", self.props, "active_document_index")


 class BIM_UL_documents(UIList):
    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
        if item:
            row = layout.row(align=True)
-            row.label(text=item.identification)
-            row.label(text=item.name)
-            if context.scene.BIMDocumentProperties.active_document_id == item.ifc_definition_id:
-                if context.scene.BIMDocumentProperties.is_editing == "information":
-                    row.operator("bim.edit_information", text="", icon="CHECKMARK")
-                elif context.scene.BIMDocumentProperties.is_editing == "reference":
-                    row.operator("bim.edit_document_reference", text="", icon="CHECKMARK")
-                row.operator("bim.disable_editing_document", text="", icon="CANCEL")
-            elif context.scene.BIMDocumentProperties.active_document_id:
-                row.operator("bim.remove_document", text="", icon="X").document = item.ifc_definition_id
-            else:
-                op = row.operator("bim.enable_editing_document", text="", icon="GREASEPENCIL")
+
+            if item.is_information:
+                op = row.operator("bim.load_document", text="", emboss=False, icon="DISCLOSURE_TRI_RIGHT")
                op.document = item.ifc_definition_id
-                row.operator("bim.remove_document", text="", icon="X").document = item.ifc_definition_id
+                row.label(text="", icon="FILE")
+            else:
+                row.label(text="", icon="BLANK1")
+                row.label(text="", icon="FILE_HIDDEN")

-
-class BIM_UL_object_documents(UIList):
-    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
-        if item:
-            row = layout.row(align=True)
-            row.label(text=item.identification)
-            row.label(text=item.name)
-            row.operator("bim.assign_document", text="", icon="ADD").document = item.ifc_definition_id
+            split1 = row.split(factor=0.1)
+            split1.label(text=item.identification)
+            split2 = split1.split(factor=0.9)
+            split2.label(text=item.name)
@@ -20,40 +20,48 @@ import bpy
 from . import ui, prop, operator, handler, gizmos

 classes = (
-    operator.AddDrawing,
-    operator.CreateDrawing,
-    operator.AddAnnotation,
-    operator.AddSheet,
-    operator.OpenSheet,
-    operator.AddDrawingToSheet,
-    operator.CreateSheets,
-    operator.OpenView,
-    operator.OpenViewCamera,
-    operator.ActivateView,
-    operator.SelectDocIfcFile,
-    operator.GenerateReferences,
-    operator.ResizeText,
-    operator.AddVariable,
-    operator.RemoveVariable,
-    operator.PropagateTextData,
-    operator.RemoveDrawing,
-    operator.AddDrawingStyle,
-    operator.RemoveDrawingStyle,
-    operator.SaveDrawingStyle,
    operator.ActivateDrawingStyle,
-    operator.EditVectorStyle,
-    operator.RemoveSheet,
-    operator.AddSchedule,
-    operator.RemoveSchedule,
-    operator.SelectScheduleFile,
-    operator.BuildSchedule,
-    operator.AddScheduleToSheet,
+    operator.ActivateView,
+    operator.AddAnnotation,
+    operator.AddDrawing,
+    operator.AddDrawingStyle,
    operator.AddDrawingStyleAttribute,
-    operator.RemoveDrawingStyleAttribute,
-    operator.RefreshDrawingList,
-    operator.CleanWireframes,
-    operator.CopyGrid,
+    operator.AddDrawingToSheet,
+    operator.AddSchedule,
+    operator.AddScheduleToSheet,
    operator.AddSectionsAnnotations,
+    operator.AddSheet,
+    operator.BuildSchedule,
+    operator.CleanWireframes,
+    operator.ContractSheet,
+    operator.CopyGrid,
+    operator.CreateDrawing,
+    operator.CreateSheets,
+    operator.DisableEditingDrawings,
+    operator.DisableEditingSheets,
+    operator.DisableEditingText,
+    operator.DisableEditingTextProduct,
+    operator.EditText,
+    operator.EditTextProduct,
+    operator.EditVectorStyle,
+    operator.EnableEditingText,
+    operator.EnableEditingTextProduct,
+    operator.ExpandSheet,
+    operator.GenerateReferences,
+    operator.LoadDrawings,
+    operator.LoadSheets,
+    operator.OpenSheet,
+    operator.OpenView,
+    operator.RemoveDrawing,
+    operator.RemoveDrawingFromSheet,
+    operator.RemoveDrawingStyle,
+    operator.RemoveDrawingStyleAttribute,
+    operator.RemoveSchedule,
+    operator.RemoveSheet,
+    operator.ResizeText,
+    operator.SaveDrawingStyle,
+    operator.SelectDocIfcFile,
+    operator.SelectScheduleFile,
    prop.Variable,
    prop.Drawing,
    prop.Schedule,
@@ -64,12 +72,13 @@ classes = (
    prop.BIMTextProperties,
    ui.BIM_PT_camera,
    ui.BIM_PT_drawing_underlay,
+    ui.BIM_PT_annotation_utilities,
+    ui.BIM_PT_sheets,
    ui.BIM_PT_drawings,
    ui.BIM_PT_schedules,
-    ui.BIM_PT_sheets,
    ui.BIM_PT_text,
-    ui.BIM_PT_annotation_utilities,
    ui.BIM_UL_drawinglist,
+    ui.BIM_UL_sheets,
    gizmos.UglyDotGizmo,
    gizmos.DotGizmo,
    gizmos.DimensionLabelGizmo,
@@ -81,6 +90,7 @@ classes = (
 def register():
    bpy.types.Scene.DocProperties = bpy.props.PointerProperty(type=prop.DocProperties)
    bpy.types.Camera.BIMCameraProperties = bpy.props.PointerProperty(type=prop.BIMCameraProperties)
+    bpy.types.Object.BIMTextProperties = bpy.props.PointerProperty(type=prop.BIMTextProperties)
    bpy.types.TextCurve.BIMTextProperties = bpy.props.PointerProperty(type=prop.BIMTextProperties)
    bpy.app.handlers.load_post.append(handler.toggleDecorationsOnLoad)
    bpy.app.handlers.depsgraph_update_pre.append(handler.depsgraph_update_pre_handler)
@@ -18,6 +18,7 @@

 import bpy
 import os
+import blenderbim.tool as tool
 from mathutils import Vector


@@ -34,13 +35,13 @@ class Annotator:
        return float(sizes[str(size)])

    @staticmethod
-    def add_text(context, related_element=None):
+    def add_text(related_element=None):
        curve = bpy.data.curves.new(type="FONT", name="Text")
        curve.body = "TEXT"
        obj = bpy.data.objects.new("Text", curve)
-        obj.matrix_world = context.scene.camera.matrix_world
+        obj.matrix_world = bpy.context.scene.camera.matrix_world
        if related_element is None:
-            location, _, _, _ = Annotator.get_placeholder_coords(context)
+            location, _, _, _ = Annotator.get_placeholder_coords(bpy.context)
        else:
            obj.data.BIMTextProperties.related_element = related_element
            location = related_element.location
@@ -49,12 +50,12 @@ class Annotator:
        font = bpy.data.fonts.get("OpenGost TypeB TT")
        if not font:
            font = bpy.data.fonts.load(
-                os.path.join(context.scene.BIMProperties.data_dir, "fonts", "OpenGost Type B TT.ttf")
+                os.path.join(bpy.context.scene.BIMProperties.data_dir, "fonts", "OpenGost Type B TT.ttf")
            )
            font.name = "OpenGost Type B TT"
        obj.data.font = font
        obj.data.BIMTextProperties.font_size = "2.5"
-        collection = context.scene.camera.users_collection[0]
+        collection = bpy.context.scene.camera.users_collection[0]
        collection.objects.link(obj)
        Annotator.resize_text(obj)
        return obj
@@ -82,9 +83,9 @@ class Annotator:
        text_obj.data.size = font_size

    @staticmethod
-    def add_line_to_annotation(obj, context, co1=None, co2=None):
+    def add_line_to_annotation(obj, co1=None, co2=None):
        if co1 is None:
-            co1, co2, _, _ = Annotator.get_placeholder_coords(context)
+            co1, co2, _, _ = Annotator.get_placeholder_coords()
        co1 = obj.matrix_world.inverted() @ co1
        co2 = obj.matrix_world.inverted() @ co2
        if isinstance(obj.data, bpy.types.Mesh):
@@ -101,8 +102,8 @@ class Annotator:
        return obj

    @staticmethod
-    def add_plane_to_annotation(obj, context):
-        co1, co2, co3, co4 = Annotator.get_placeholder_coords(context)
+    def add_plane_to_annotation(obj):
+        co1, co2, co3, co4 = Annotator.get_placeholder_coords()
        co1 = obj.matrix_world.inverted() @ co1  # bot left
        co2 = obj.matrix_world.inverted() @ co2  # top left
        co3 = obj.matrix_world.inverted() @ co3  # bot right
@@ -150,27 +151,43 @@ class Annotator:
        return obj

    @staticmethod
-    def get_annotation_obj(name, data_type, context):
-        collection = context.scene.camera.users_collection[0]
-        for obj in collection.objects:
-            if name in obj.name:
-                return obj
-        if data_type == "mesh":
-            data = bpy.data.meshes.new(name)
-        elif data_type == "curve":
-            data = bpy.data.curves.new(name, type="CURVE")
+    def get_annotation_obj(object_type, data_type):
+        collection = bpy.context.scene.camera.users_collection[0]
+        if object_type == "TEXT":
+            obj = bpy.data.objects.new(object_type, None)
+            collection.objects.link(obj)
+            return obj
+        elif object_type == "TEXT_LEADER":
+            data = bpy.data.curves.new(object_type, type="CURVE")
            data.dimensions = "3D"
            data.resolution_u = 2
-        obj = bpy.data.objects.new(name, data)
+            obj = bpy.data.objects.new(object_type, data)
+            collection.objects.link(obj)
+            return obj
+        for obj in collection.objects:
+            element = tool.Ifc.get_entity(obj)
+            if element and element.ObjectType == object_type:
+                return obj
+        if data_type == "mesh":
+            data = bpy.data.meshes.new(object_type)
+        elif data_type == "curve":
+            data = bpy.data.curves.new(object_type, type="CURVE")
+            data.dimensions = "3D"
+            data.resolution_u = 2
+        obj = bpy.data.objects.new(object_type, data)
        collection.objects.link(obj)
        return obj

    @staticmethod
-    def get_placeholder_coords(context):
-        camera = context.scene.camera
+    def get_placeholder_coords():
+        camera = bpy.context.scene.camera
        z_offset = camera.matrix_world.to_quaternion() @ Vector((0, 0, -1))
-        if context.scene.render.resolution_x > context.scene.render.resolution_y:
-            y = camera.data.ortho_scale * (context.scene.render.resolution_y / context.scene.render.resolution_x) / 4
+        if bpy.context.scene.render.resolution_x > bpy.context.scene.render.resolution_y:
+            y = (
+                camera.data.ortho_scale
+                * (bpy.context.scene.render.resolution_y / bpy.context.scene.render.resolution_x)
+                / 4
+            )
        else:
            y = camera.data.ortho_scale / 4
        y_offset = camera.matrix_world.to_quaternion() @ Vector((0, y, 0))
@@ -0,0 +1,96 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+import ifcopenshell.util.representation
+import blenderbim.tool as tool
+
+
+def refresh():
+    TextData.is_loaded = False
+    SheetsData.is_loaded = False
+    DrawingsData.is_loaded = False
+
+
+class TextData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {"attributes": cls.attributes(), "relating_product": cls.relating_product()}
+        cls.is_loaded = True
+
+    @classmethod
+    def attributes(cls):
+        element = tool.Ifc.get_entity(bpy.context.active_object)
+        if not element or not element.is_a("IfcAnnotation") or element.ObjectType not in ["TEXT", "TEXT_LEADER"]:
+            return []
+        rep = ifcopenshell.util.representation.get_representation(element, "Plan", "Annotation")
+        text_literal = [i for i in rep.Items if i.is_a("IfcTextLiteral")][0]
+        return [
+            {"name": "Literal", "value": text_literal.Literal},
+            {"name": "BoxAlignment", "value": text_literal.BoxAlignment},
+        ]
+
+    @classmethod
+    def relating_product(cls):
+        element = tool.Ifc.get_entity(bpy.context.active_object)
+        if not element or not element.is_a("IfcAnnotation") or element.ObjectType not in ["TEXT", "TEXT_LEADER"]:
+            return
+        for rel in element.HasAssignments:
+            if rel.is_a("IfcRelAssignsToProduct"):
+                return rel.RelatingProduct.Name or "Unnamed"
+
+
+class SheetsData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {"total_sheets": cls.total_sheets()}
+        cls.is_loaded = True
+
+    @classmethod
+    def total_sheets(cls):
+        return len([d for d in tool.Ifc.get().by_type("IfcDocumentInformation") if d.Scope == "DOCUMENTATION"])
+
+
+class DrawingsData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {"total_drawings": cls.total_drawings(), "location_hint": cls.location_hint()}
+        cls.is_loaded = True
+
+    @classmethod
+    def total_drawings(cls):
+        return len([e for e in tool.Ifc.get().by_type("IfcAnnotation") if e.ObjectType == "DRAWING"])
+
+    @classmethod
+    def location_hint(cls):
+        if bpy.context.scene.DocProperties.target_view in ["PLAN_VIEW", "REFLECTED_PLAN_VIEW"]:
+            results = [("0", "Origin", "")]
+            results.extend(
+                [(str(s.id()), s.Name or "Unnamed", "") for s in tool.Ifc.get().by_type("IfcBuildingStorey")]
+            )
+            return results
+        return [(h.upper(), h, "") for h in ["North", "South", "East", "West"]]
@@ -16,32 +16,32 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

-"""Viewport decorations"""
+import os
+import gpu
+import bpy
+import blf
+import bgl
 import math
+import bmesh
+import blenderbim.tool as tool
+import blenderbim.bim.module.drawing.helper as helper
 from functools import reduce
 from itertools import chain
-
 from bpy.types import SpaceView3D
 from mathutils import Vector, Matrix
-import bpy
-import bmesh
-import blf
 from bpy_extras.view3d_utils import location_3d_to_region_2d
-import gpu
-import bgl
 from gpu.types import GPUShader, GPUBatch, GPUIndexBuf, GPUVertBuf, GPUVertFormat
 from gpu_extras.batch import batch_for_shader
-import blenderbim.bim.module.drawing.helper as helper


 class BaseDecorator:
    # base name of objects to decorate
-    basename = "IfcAnnotation/Something"
+    objecttype = "NOTDEFINED"

    DEF_GLSL = """
        #define PI 3.141592653589793
        #define MAX_POINTS 64
-        #define CIRCLE_SEGS 24
+        #define CIRCLE_SEGS 12
    """

    LIB_GLSL = """
@@ -90,6 +90,7 @@ class BaseDecorator:

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=2) out;
@@ -134,13 +135,48 @@ class BaseDecorator:
            defines=self.DEF_GLSL,
        )

+        # Horrific prototype code to ensure bgl draws at drawing scales
+        # https://blender.stackexchange.com/questions/16493/is-there-a-way-to-fit-the-viewport-to-the-current-field-of-view
+        def is_landscape(render):
+            return render.resolution_x > render.resolution_y
+
+        def get_scale(camera):
+            if camera.data.BIMCameraProperties.diagram_scale == "CUSTOM":
+                human_scale, fraction = camera.data.BIMCameraProperties.custom_diagram_scale.split("|")
+            else:
+                human_scale, fraction = camera.data.BIMCameraProperties.diagram_scale.split("|")
+            numerator, denominator = fraction.split("/")
+            return float(numerator) / float(denominator)
+
+        camera = bpy.context.scene.camera
+        render = bpy.context.scene.render
+        if is_landscape(render):
+            camera_width_model = camera.data.ortho_scale
+        else:
+            camera_width_model = camera.data.ortho_scale / render.resolution_y * render.resolution_x
+        self.camera_width_mm = get_scale(camera) * camera_width_model
+
+        self.font_id = blf.load(
+            os.path.join(bpy.context.scene.BIMProperties.data_dir, "fonts", "OpenGost Type B TT.ttf")
+        )
+
+    def camera_zoom_to_factor(self, zoom):
+        return math.pow(((zoom / 50) + math.sqrt(2)) / 2, 2)
+
    def get_objects(self, collection):
        """find relevant objects
-        using class.basename
+        using class.objecttype

        returns: iterable of blender objects
        """
-        return filter(lambda o: self.basename in o.name, collection.all_objects)
+        results = []
+        for obj in collection.all_objects:
+            element = tool.Ifc.get_entity(obj)
+            if not element:
+                continue
+            if element.is_a("IfcAnnotation") and element.ObjectType == self.objecttype:
+                results.append(obj)
+        return results

    def get_path_geom(self, obj, topo=True):
        """Parses path geometry into line segments
@@ -208,7 +244,7 @@ class BaseDecorator:
        return vertices, indices

    def decorate(self, context, object):
-        """perform actuall drawing stuff"""
+        """perform actual drawing stuff"""
        raise NotImplementedError()

    def draw_lines(self, context, obj, vertices, indices, topology=None):
@@ -241,6 +277,15 @@ class BaseDecorator:
        self.shader.uniform_float("winsize", (region.width, region.height))
        self.shader.uniform_float("color", color)

+        # Horrific prototype code
+        factor = self.camera_zoom_to_factor(context.space_data.region_3d.view_camera_zoom)
+        camera_width_px = factor * context.region.width
+        mm_to_px = camera_width_px / self.camera_width_mm
+        # 0.00025 is a magic constant number I visually discovered to get the right number.
+        # It probably should be dynamically calculated using system.dpi or something.
+        viewport_drawing_scale = 0.00025 * mm_to_px
+        self.shader.uniform_float("viewportDrawingScale", viewport_drawing_scale)
+
        batch.draw(self.shader)

    def draw_label(self, context, text, pos, dir, gap=4, center=True, vcenter=False):
@@ -251,8 +296,9 @@ class BaseDecorator:

        aligned and centered at segment middle
        """
-        font_id = 0
-        font_size = 16
+        # 0 is the default font, but we're fancier than that
+        font_id = self.font_id
+
        dpi = context.preferences.system.dpi

        color = context.scene.DocProperties.decorations_colour
@@ -261,6 +307,16 @@ class BaseDecorator:
        cos = math.cos(ang)
        sin = math.sin(ang)

+        # Horrific prototype code
+        factor = self.camera_zoom_to_factor(context.space_data.region_3d.view_camera_zoom)
+        camera_width_px = factor * context.region.width
+        mm_to_px = camera_width_px / self.camera_width_mm
+        # 0.004118616 is a magic constant number I visually discovered to get the right number.
+        # In particular it works only for the OpenGOST font and produces a 2.5mm font size.
+        # It probably should be dynamically calculated using system.dpi or something.
+        # font_size = 16 <-- this is a good default
+        font_size = int(0.004118616 * mm_to_px)
+
        blf.size(font_id, font_size, dpi)

        w, h = 0, 0
@@ -284,6 +340,9 @@ class BaseDecorator:

        blf.rotation(font_id, ang)
        blf.color(font_id, *color)
+        # blf.enable(font_id, blf.SHADOW)
+        # blf.shadow(font_id, 5, 0, 0, 0, 1)
+        # blf.shadow_offset(font_id, 1, -1)
        blf.draw(font_id, text)
        blf.disable(font_id, blf.ROTATION)

@@ -302,7 +361,7 @@ class BaseDecorator:
        else:
            return

-        return bpy.utils.units.to_string(unit_system, "LENGTH", value, precision, split_unit=True)
+        return bpy.utils.units.to_string(unit_system, "LENGTH", value, precision=precision, split_unit=True)


 class DimensionDecorator(BaseDecorator):
@@ -311,7 +370,7 @@ class DimensionDecorator(BaseDecorator):
    - puts metric text next to each segment
    """

-    basename = "IfcAnnotation/Dimension"
+    objecttype = "DIMENSION"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
@@ -323,6 +382,7 @@ class DimensionDecorator(BaseDecorator):

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -339,7 +399,7 @@ class DimensionDecorator(BaseDecorator):
        vec4 p;

        vec4 head[3];
-        arrow_head(dir, ARROW_SIZE, ARROW_ANGLE, head);
+        arrow_head(dir, viewportDrawingScale * ARROW_SIZE, ARROW_ANGLE, head);

        // start edge arrow
        gl_Position = p0;
@@ -406,7 +466,7 @@ class EqualityDecorator(DimensionDecorator):
    - puts 'EQ' label
    """

-    basename = "IfcAnnotation/Equal"
+    objecttype = "EQUAL_DIMENSION"

    def draw_labels(self, context, obj, vertices, indices):
        region = context.region
@@ -423,12 +483,11 @@ class EqualityDecorator(DimensionDecorator):


 class LeaderDecorator(BaseDecorator):
-    """Decorating stairs
+    """Decorating text with arrows
    - head point with arrow
-    - middle points w/out decorations
    """

-    basename = "IfcAnnotation/Leader"
+    objecttype = "TEXT_LEADER"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
@@ -440,6 +499,7 @@ class LeaderDecorator(BaseDecorator):

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -461,7 +521,7 @@ class LeaderDecorator(BaseDecorator):
        // end edge arrow for last segment
        if (t1 == 2u) {
            vec4 head[3];
-            arrow_head(dir, ARROW_SIZE, ARROW_ANGLE, head);
+            arrow_head(dir, viewportDrawingScale * ARROW_SIZE, ARROW_ANGLE, head);

            gl_Position = p1;
            EmitVertex();
@@ -475,7 +535,7 @@ class LeaderDecorator(BaseDecorator):
            EmitVertex();
            EndPrimitive();

-            gap1 = dir * ARROW_SIZE;
+            gap1 = dir * viewportDrawingScale * ARROW_SIZE;
        }

        // stem, adjusted for and arrow
@@ -488,9 +548,24 @@ class LeaderDecorator(BaseDecorator):
    }
    """

+    def get_spline_end(self, obj):
+        spline = obj.data.splines[0]
+        spline_points = spline.bezier_points if spline.bezier_points else spline.points
+        if not spline_points:
+            return Vector((0, 0, 0))
+        return obj.matrix_world @ spline_points[0].co
+
    def decorate(self, context, obj):
        verts, idxs, topo = self.get_path_geom(obj)
        self.draw_lines(context, obj, verts, idxs, topo)
+        self.draw_labels(context, obj)
+
+    def draw_labels(self, context, obj):
+        region = context.region
+        region3d = context.region_data
+        dir = Vector((1, 0))
+        pos = location_3d_to_region_2d(region, region3d, self.get_spline_end(obj))
+        self.draw_label(context, obj.BIMTextProperties.value, pos, dir, gap=0, center=False, vcenter=False)


 class StairDecorator(BaseDecorator):
@@ -500,12 +575,12 @@ class StairDecorator(BaseDecorator):
    - middle points w/out decorations
    """

-    basename = "IfcAnnotation/Stair"
+    objecttype = "STAIR_ARROW"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
        + """
-        #define CIRCLE_SIZE 8.0
+        #define CIRCLE_SIZE 6.0
        #define ARROW_ANGLE PI / 3.0
        #define ARROW_SIZE 24.0
    """
@@ -513,6 +588,7 @@ class StairDecorator(BaseDecorator):

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -534,7 +610,7 @@ class StairDecorator(BaseDecorator):
        // start edge circle for first segment
        if (t0 == 1u) {
            vec4 head[CIRCLE_SEGS];
-            circle_head(CIRCLE_SIZE, head);
+            circle_head(viewportDrawingScale * CIRCLE_SIZE, head);

            for(int i=0; i<CIRCLE_SEGS; i++) {
                p = p0w + head[i];
@@ -546,13 +622,13 @@ class StairDecorator(BaseDecorator):
            EmitVertex();
            EndPrimitive();

-            gap0 = dir * CIRCLE_SIZE;
+            gap0 = dir * viewportDrawingScale * CIRCLE_SIZE;
        }

        // end edge arrow for last segment
        if (t1 == 2u) {
            vec4 head[3];
-            arrow_head(dir, ARROW_SIZE, ARROW_ANGLE, head);
+            arrow_head(dir, viewportDrawingScale * ARROW_SIZE, ARROW_ANGLE, head);

            p = p1w - head[1];
            gl_Position = WIN2CLIP(p);
@@ -583,7 +659,7 @@ class StairDecorator(BaseDecorator):


 class HiddenDecorator(BaseDecorator):
-    basename = "IfcAnnotation/Hidden"
+    objecttype = "HIDDEN_LINE"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
@@ -628,13 +704,14 @@ class HiddenDecorator(BaseDecorator):
    """

    FRAG_GLSL = """
+    uniform float viewportDrawingScale;
    uniform vec4 color;
    in vec2 gl_FragCoord;
    in float dist;
    out vec4 fragColor;

    void main() {
-        uint bit = uint(fract(dist / DASH_SIZE) * 32);
+        uint bit = uint(fract(dist / (viewportDrawingScale * DASH_SIZE)) * 32);
        if ((DASH_PATTERN & (1U<<bit)) == 0U) discard;
        fragColor = color;
    }
@@ -649,7 +726,7 @@ class HiddenDecorator(BaseDecorator):


 class MiscDecorator(HiddenDecorator):
-    basename = "IfcAnnotation/Misc"
+    objecttype = "MISC"

    FRAG_GLSL = BaseDecorator.FRAG_GLSL

@@ -677,7 +754,7 @@ class LevelDecorator(BaseDecorator):


 class PlanLevelDecorator(LevelDecorator):
-    basename = "IfcAnnotation/Plan Level"
+    objecttype = "PLAN_LEVEL"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
@@ -689,6 +766,7 @@ class PlanLevelDecorator(LevelDecorator):

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -710,7 +788,7 @@ class PlanLevelDecorator(LevelDecorator):
        // end edge cross+circle for last segment
        if (t1 == 2u) {
            vec4 head_o[CIRCLE_SEGS];
-            circle_head(CIRCLE_SIZE, head_o);
+            circle_head(viewportDrawingScale * CIRCLE_SIZE, head_o);

            for(int i=0; i<CIRCLE_SEGS; i++) {
                p = p1w + head_o[i];
@@ -723,7 +801,7 @@ class PlanLevelDecorator(LevelDecorator):
            EndPrimitive();

            vec4 head_x[3];
-            cross_head(dir, CROSS_SIZE, head_x);
+            cross_head(dir, viewportDrawingScale * CROSS_SIZE, head_x);

            p = p1w + head_x[1];
            gl_Position = WIN2CLIP(p);
@@ -762,7 +840,7 @@ class PlanLevelDecorator(LevelDecorator):


 class SectionLevelDecorator(LevelDecorator):
-    basename = "IfcAnnotation/Section Level"
+    objecttype = "SECTION_LEVEL"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
@@ -774,6 +852,7 @@ class SectionLevelDecorator(LevelDecorator):

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -781,8 +860,8 @@ class SectionLevelDecorator(LevelDecorator):
    out float dist; // distance from starging point along segment

    void callout_head(in vec4 dir, out vec4 head[4]) {
-        vec2 gap = dir.xy * CALLOUT_GAP;
-        vec2 tail = dir.xy * -CALLOUT_SIZE;
+        vec2 gap = dir.xy * viewportDrawingScale * CALLOUT_GAP;
+        vec2 tail = dir.xy * viewportDrawingScale * -CALLOUT_SIZE;
        vec2 side = cross(vec3(dir.xy, 0), vec3(0, 0, 1)).xy * CALLOUT_GAP;

        head[0] = vec4(tail + side, 0, 0);
@@ -850,7 +929,7 @@ class BreakDecorator(BaseDecorator):
    Uses first two vertices in verts list.
    """

-    basename = "IfcAnnotation/Break"
+    objecttype = "BREAKLINE"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
@@ -862,6 +941,7 @@ class BreakDecorator(BaseDecorator):

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -878,8 +958,8 @@ class BreakDecorator(BaseDecorator):

        vec4 p;

-        vec4 quart = dir * BREAK_LENGTH * .25;
-        vec4 side = vec4(cross(vec3(dir.xy, 0), vec3(0, 0, 1)).xy, 0, 0) * BREAK_WIDTH;
+        vec4 quart = dir * viewportDrawingScale * BREAK_LENGTH * .25;
+        vec4 side = vec4(cross(vec3(dir.xy, 0), vec3(0, 0, 1)).xy, 0, 0) * viewportDrawingScale * BREAK_WIDTH;

        // TODO: check if there's enough length for zigzag

@@ -928,7 +1008,7 @@ class BreakDecorator(BaseDecorator):


 class GridDecorator(BaseDecorator):
-    basename = "IfcGridAxis/"
+    objecttype = "GRID"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
@@ -941,6 +1021,7 @@ class GridDecorator(BaseDecorator):

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -955,12 +1036,12 @@ class GridDecorator(BaseDecorator):

        vec4 p0w = CLIP2WIN(p0), p1w = CLIP2WIN(p1);
        vec4 edge = p1w - p0w, dir = normalize(edge);
-        vec4 gap = dir * CIRCLE_SIZE;
+        vec4 gap = dir * CIRCLE_SIZE * viewportDrawingScale;

        vec4 p;

        vec4 head[CIRCLE_SEGS];
-        circle_head(CIRCLE_SIZE, head);
+        circle_head(CIRCLE_SIZE * viewportDrawingScale, head);

        dist = 0;

@@ -1044,30 +1125,33 @@ class GridDecorator(BaseDecorator):
        self.draw_label(context, text, p1, dir, vcenter=True, gap=0)


-class SectionViewDecorator(LevelDecorator):
-    basename = "IfcAnnotation/Section"
+class ElevationDecorator(LevelDecorator):
+    objecttype = "ELEVATION"

    DEF_GLSL = (
        BaseDecorator.DEF_GLSL
        + """
        #define CIRCLE_SIZE 8.0
-        #define TRIANGLE_L 32.0
-        #define TRIANGLE_W 16.0
+        #define TRIANGLE_L 22.63
+        #define TRIANGLE_W 11.31
    """
    )

    GEOM_GLSL = """
    uniform vec2 winsize;
+    uniform float viewportDrawingScale;

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;

-    void triangle_head(in vec4 dir, in vec4 side, in float length, in float width, out vec4 head[3]) {
-        vec4 nose = dir * length;
-        vec4 ear = side * width;
-        head[0] = vec4(0);
-        head[1] = nose * .5 + ear;
-        head[2] = nose;
+    void triangle_head(in vec4 side, in vec4 dir, in float length, in float width, in float radius, out vec4 head[5]) {
+        vec4 nose = side * length;
+        vec4 ear = dir * width;
+        head[0] = side * -radius;
+        head[1] = nose * -.5;
+        head[2] = vec4(0) + ear;
+        head[3] = nose * .5;
+        head[4] = side * radius;
    }

    void main() {
@@ -1078,75 +1162,290 @@ class SectionViewDecorator(LevelDecorator):

        vec4 p0w = CLIP2WIN(p0), p1w = CLIP2WIN(p1);
        vec4 edge = p1w - p0w, dir = normalize(edge);
-        vec4 gap = dir * TRIANGLE_L * .5;
        vec4 side = vec4(cross(vec3(dir.xy, 0), vec3(0, 0, 1)).xy, 0, 0);
        vec4 p;

        vec4 head[CIRCLE_SEGS];
-        circle_head(CIRCLE_SIZE, head);
+        circle_head(viewportDrawingScale * CIRCLE_SIZE, head);

-        vec4 head3[3];
+        vec4 head5[5];

        // start edge circle
        for(int i=0; i<CIRCLE_SEGS; i++) {
-            p = p0w + gap + head[i];
+            p = p0w + head[i];
            gl_Position = WIN2CLIP(p);
            EmitVertex();
        }
-        p = p0w + gap + head[0];
+        p = p0w + head[0];
        gl_Position = WIN2CLIP(p);
        EmitVertex();
        EndPrimitive();

-        // start edge triangle
-        triangle_head(dir, -side, TRIANGLE_L, TRIANGLE_W, head3);
-        p = p0w + head3[0];
+        // edge triangle
+        triangle_head(side, dir, viewportDrawingScale * TRIANGLE_L, viewportDrawingScale * TRIANGLE_W, viewportDrawingScale * CIRCLE_SIZE, head5);
+        p = p0w + head5[0];
        gl_Position = WIN2CLIP(p);
        EmitVertex();
-        p = p0w + head3[1];
+        p = p0w + head5[1];
        gl_Position = WIN2CLIP(p);
        EmitVertex();
-        p = p0w + head3[2];
+        p = p0w + head5[2];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + head5[3];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + head5[4];
        gl_Position = WIN2CLIP(p);
        EmitVertex();
        EndPrimitive();

-        // end edge circle
-        for(int i=0; i<CIRCLE_SEGS; i++) {
-            p = p1w - gap + head[i];
-            gl_Position = WIN2CLIP(p);
-            EmitVertex();
-        }
-        p = p1w - gap + head[0];
+        // reference divider
+        p = p0w + normalize(vec4(-1, 0, 0, 0)) * viewportDrawingScale * CIRCLE_SIZE;
        gl_Position = WIN2CLIP(p);
        EmitVertex();
-        EndPrimitive();
-
-        // end edge triangle
-        triangle_head(-dir, -side, TRIANGLE_L, TRIANGLE_W, head3);
-        p = p1w + head3[0];
+        p = p0w + normalize(vec4(1, 0, 0, 0)) * viewportDrawingScale * CIRCLE_SIZE;
        gl_Position = WIN2CLIP(p);
        EmitVertex();
-        p = p1w + head3[1];
-        gl_Position = WIN2CLIP(p);
-        EmitVertex();
-        p = p1w + head3[2];
-        gl_Position = WIN2CLIP(p);
-        EmitVertex();
-        EndPrimitive();
-
-        // stem
-        gl_Position = p0;
-        EmitVertex();
-        gl_Position = p1;
-        EmitVertex();
        EndPrimitive();
    }
    """

    def decorate(self, context, obj):
-        verts, _, _ = self.get_path_geom(obj, topo=False)
-        self.draw_lines(context, obj, verts, [(0, 1)])
+        center = obj.matrix_world.translation
+        v1 = obj.matrix_world @ Vector((0, 0, 0))
+        v2 = obj.matrix_world @ Vector((0, 0, -1))
+        self.draw_lines(context, obj, [v1, v2], [(0, 1)])
+
+
+class SectionDecorator(LevelDecorator):
+    objecttype = "SECTION"
+
+    DEF_GLSL = (
+        BaseDecorator.DEF_GLSL
+        + """
+        #define CIRCLE_SIZE 8.0
+        #define TRIANGLE_L 22.63
+        #define TRIANGLE_W 11.31
+    """
+    )
+
+    GEOM_GLSL = """
+    uniform vec2 winsize;
+    uniform float viewportDrawingScale;
+
+    layout(lines) in;
+    layout(line_strip, max_vertices=MAX_POINTS) out;
+
+    void triangle_head(in vec4 side, in vec4 dir, in float length, in float width, in float radius, out vec4 head[5]) {
+        vec4 nose = side * length;
+        vec4 ear = dir * width;
+        head[0] = side * -radius;
+        head[1] = nose * -.5;
+        head[2] = vec4(0) + ear;
+        head[3] = nose * .5;
+        head[4] = side * radius;
+    }
+
+    void main() {
+        vec4 clip2win = matCLIP2WIN();
+        vec4 win2clip = matWIN2CLIP();
+
+        vec4 p0 = gl_in[0].gl_Position, p1 = gl_in[1].gl_Position;
+
+        vec4 p0w = CLIP2WIN(p0), p1w = CLIP2WIN(p1);
+        vec4 edge = p1w - p0w, side = normalize(edge);
+        vec4 gap = side * viewportDrawingScale * CIRCLE_SIZE;
+        vec4 dir = vec4(cross(vec3(side.xy, 0), vec3(0, 0, 1)).xy, 0, 0);
+        vec4 p;
+
+        vec4 head[CIRCLE_SEGS];
+        circle_head(viewportDrawingScale * CIRCLE_SIZE, head);
+
+        vec4 head5[5];
+
+        // start edge circle
+        for(int i=0; i<CIRCLE_SEGS; i++) {
+            p = p0w + head[i];
+            gl_Position = WIN2CLIP(p);
+            EmitVertex();
+        }
+        p = p0w + head[0];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+
+        // start edge triangle
+        triangle_head(side, dir, viewportDrawingScale * TRIANGLE_L, viewportDrawingScale * TRIANGLE_W, viewportDrawingScale * CIRCLE_SIZE, head5);
+        p = p0w + head5[0];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + head5[1];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + head5[2];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + head5[3];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + head5[4];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+
+        // start reference divider
+        p = p0w + normalize(vec4(-1, 0, 0, 0)) * viewportDrawingScale * CIRCLE_SIZE;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + normalize(vec4(1, 0, 0, 0)) * viewportDrawingScale * CIRCLE_SIZE;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+
+        // end edge circle
+        for(int i=0; i<CIRCLE_SEGS; i++) {
+            p = p1w - head[i];
+            gl_Position = WIN2CLIP(p);
+            EmitVertex();
+        }
+        p = p1w - head[0];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+
+        // end edge triangle
+        triangle_head(side, dir, viewportDrawingScale * TRIANGLE_L, viewportDrawingScale * TRIANGLE_W, viewportDrawingScale * CIRCLE_SIZE, head5);
+        p = p1w + head5[0];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w + head5[1];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w + head5[2];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w + head5[3];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w + head5[4];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+
+        // end reference divider
+        p = p1w + normalize(vec4(-1, 0, 0, 0)) * viewportDrawingScale * CIRCLE_SIZE;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w + normalize(vec4(1, 0, 0, 0)) * viewportDrawingScale * CIRCLE_SIZE;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+
+        // stem
+        p = p0w + gap;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w - gap;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+    }
+    """
+
+    def decorate(self, context, obj):
+        if obj.data.is_editmode:
+            verts, idxs = self.get_editmesh_geom(obj)
+        else:
+            verts, idxs = self.get_mesh_geom(obj)
+        vert_map = {v.freeze(): (obj.matrix_world.inverted() @ v).x for v in verts}
+        verts = sorted(verts, key=lambda v: vert_map[v], reverse=True)
+        self.draw_lines(context, obj, verts, idxs)
+
+
+
+class TextDecorator(BaseDecorator):
+    """Decorator for text objects
+    - draws the text next to the origin
+    """
+
+    objecttype = "TEXT"
+
+    DEF_GLSL = (
+        BaseDecorator.DEF_GLSL
+        + """
+        #define ARROW_ANGLE PI / 12.0
+        #define ARROW_SIZE 16.0
+    """
+    )
+
+    GEOM_GLSL = """
+    uniform vec2 winsize;
+    uniform float viewportDrawingScale;
+
+    layout(lines) in;
+    layout(line_strip, max_vertices=MAX_POINTS) out;
+
+    void main() {
+        vec4 clip2win = matCLIP2WIN();
+        vec4 win2clip = matWIN2CLIP();
+
+        vec4 p0 = gl_in[0].gl_Position, p1 = gl_in[1].gl_Position;
+
+        vec4 p0w = CLIP2WIN(p0), p1w = CLIP2WIN(p1);
+        vec4 edge = p1w - p0w, dir = normalize(edge);
+
+        vec4 p;
+
+        vec4 head[3];
+        arrow_head(dir, viewportDrawingScale * ARROW_SIZE, ARROW_ANGLE, head);
+
+        // start edge arrow
+        gl_Position = p0;
+        EmitVertex();
+        p = p0w + head[1];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p0w + head[2];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        gl_Position = p0;
+        EmitVertex();
+        EndPrimitive();
+
+        // end edge arrow
+        gl_Position = p1;
+        EmitVertex();
+        p = p1w - head[1];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w - head[2];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        gl_Position = p1;
+        EmitVertex();
+        EndPrimitive();
+
+        // stem, with gaps for arrows
+        p = p0w + head[0];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        p = p1w - head[0];
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+    }
+    """
+
+    def decorate(self, context, obj):
+        self.draw_labels(context, obj)
+
+    def draw_labels(self, context, obj):
+        region = context.region
+        region3d = context.region_data
+        dir = Vector((1, 0))
+        pos = location_3d_to_region_2d(region, region3d, obj.matrix_world.translation)
+        self.draw_label(context, obj.BIMTextProperties.value, pos, dir, gap=0, center=False, vcenter=False)


 class DecorationsHandler:
@@ -1161,7 +1460,9 @@ class DecorationsHandler:
        SectionLevelDecorator,
        StairDecorator,
        BreakDecorator,
-        SectionViewDecorator,
+        SectionDecorator,
+        ElevationDecorator,
+        TextDecorator,
    ]

    installed = None
@@ -45,6 +45,3 @@ def set_active_camera_resolution(scene):
        scene.render.resolution_x = scene.camera.data.BIMCameraProperties.raster_x
        scene.render.resolution_y = scene.camera.data.BIMCameraProperties.raster_y
    current_drawing = scene.DocProperties.drawings[scene.DocProperties.current_drawing_index]
-    if scene.camera != current_drawing.camera:
-        scene.DocProperties.current_drawing_index = scene.DocProperties.drawings.find(scene.camera.name.split("/")[1])
-        bpy.ops.bim.activate_view(drawing_index=scene.DocProperties.current_drawing_index)
@@ -19,6 +19,7 @@
 import bpy
 import math
 import mathutils.geometry
+import blenderbim.tool as tool
 from mathutils import Vector

 # Code taken and updated from https://blenderartists.org/t/detecting-intersection-of-bounding-boxes/457520/2
@@ -259,13 +260,11 @@ def format_distance(value, isArea=False, hide_units=True):
 def get_active_drawing(scene):
    """Get active drawing collection and camera"""
    props = scene.DocProperties
-    if props.active_drawing_index is None or len(props.drawings) == 0:
-        return None, None
    try:
-        drawing = props.active_drawing
-        return scene.collection.children["Views"].children[f"IfcGroup/{drawing.name}"], drawing.camera
-    except (KeyError, IndexError):
-        raise RuntimeError("missing drawing collection")
+        camera = tool.Ifc.get_object(tool.Ifc.get().by_id(props.active_drawing_id))
+        return camera.users_collection[0], camera
+    except:
+        return None, None


 def get_project_collection(scene):
@@ -18,11 +18,14 @@

 import os
 import bpy
+import json
+import enum
 import ifcopenshell
 import blenderbim.tool as tool
+import blenderbim.core.drawing as core
 import blenderbim.bim.module.drawing.annotation as annotation
 import blenderbim.bim.module.drawing.decoration as decoration
-import enum
+from blenderbim.bim.module.drawing.data import DrawingsData
 from pathlib import Path
 from blenderbim.bim.prop import Attribute, StrProperty
 from bpy.types import PropertyGroup
@@ -55,12 +58,24 @@ def purge():
    vector_styles_enum = []


+def update_target_view(self, context):
+    DrawingsData.data["location_hint"] = DrawingsData.location_hint()
+
+
+def get_location_hint(self, context):
+    if not DrawingsData.is_loaded:
+        DrawingsData.load()
+    return DrawingsData.data["location_hint"]
+
+
 def update_diagram_scale(self, context):
    scale = self.diagram_scale
    if scale == "CUSTOM":
        scale = self.custom_diagram_scale
-    scale = scale.split("|")[1]
-    element = tool.Ifc.get_entity(context.scene.camera)
+    if "|" not in scale:
+        return
+    human_scale, scale = scale.split("|")
+    element = tool.Ifc.get_entity(context.active_object)
    if not element:
        return
    pset = ifcopenshell.util.element.get_psets(element).get("EPset_Drawing")
@@ -68,7 +83,9 @@ def update_diagram_scale(self, context):
        pset = tool.Ifc.get().by_id(pset["id"])
    else:
        pset = ifcopenshell.api.run("pset.add_pset", tool.Ifc.get(), product=element, name="EPset_Drawing")
-    ifcopenshell.api.run("pset.edit_pset", tool.Ifc.get(), pset=pset, properties={"Scale": scale})
+    ifcopenshell.api.run(
+        "pset.edit_pset", tool.Ifc.get(), pset=pset, properties={"Scale": scale, "HumanScale": human_scale}
+    )


 def get_diagram_scales(self, context):
@@ -131,31 +148,42 @@ def get_diagram_scales(self, context):
    return diagram_scales_enum


-def updateDrawingName(self, context):
-    if not self.camera:
-        return
-    if self.camera.name == self.name:
-        return
-    self.camera.name = "IfcAnnotation/{}".format(self.name)
-    unique_name = "/".join(self.camera.name.split("/")[1:])
-    self.camera.users_collection[0].name = "IfcGroup/{}".format(unique_name)
-    if self.name != unique_name:
-        self.name = unique_name
+def update_drawing_name(self, context):
+    drawing = tool.Ifc.get().by_id(self.ifc_definition_id)
+    core.update_drawing_name(tool.Ifc, tool.Drawing, drawing=drawing, name=self.name)


-def refreshActiveDrawingIndex(self, context):
-    bpy.ops.bim.activate_view(drawing_index=context.scene.DocProperties.active_drawing_index)
+def update_has_underlay(self, context):
+    update_layer(self, context, "HasUnderlay", self.has_underlay)
+
+
+def update_has_linework(self, context):
+    update_layer(self, context, "HasLinework", self.has_linework)
+
+
+def update_has_annotation(self, context):
+    update_layer(self, context, "HasAnnotation", self.has_annotation)
+
+
+def update_layer(self, context, name, value):
+    element = tool.Ifc.get_entity(context.active_object)
+    if not element:
+        return
+    pset = ifcopenshell.util.element.get_psets(element).get("EPset_Drawing")
+    if pset:
+        pset = tool.Ifc.get().by_id(pset["id"])
+    else:
+        pset = ifcopenshell.api.run("pset.add_pset", tool.Ifc.get(), product=element, name="EPset_Drawing")
+    ifcopenshell.api.run("pset.edit_pset", tool.Ifc.get(), pset=pset, properties={name: value})


 def getTitleblocks(self, context):
    global titleblocks_enum
    if len(titleblocks_enum) < 1:
        titleblocks_enum.clear()
-        for filename in Path(os.path.join(context.scene.BIMProperties.data_dir, "templates", "titleblocks")).glob(
-            "*.svg"
-        ):
-            f = str(filename.stem)
-            titleblocks_enum.append((f, f, ""))
+        files = Path(os.path.join(context.scene.BIMProperties.data_dir, "templates", "titleblocks")).glob("*.svg")
+        files = sorted([str(f.stem) for f in files])
+        titleblocks_enum.extend([(f, f, "") for f in files])
    return titleblocks_enum


@@ -168,6 +196,10 @@ def refreshTitleblocks(self, context):
 def toggleDecorations(self, context):
    toggle = self.should_draw_decorations
    if toggle:
+        # TODO: design a proper text variable templating renderer
+        collection = context.scene.camera.users_collection[0]
+        for obj in collection.objects:
+            tool.Drawing.update_text_value(obj)
        decoration.DecorationsHandler.install(context)
    else:
        decoration.DecorationsHandler.uninstall()
@@ -193,8 +225,9 @@ class Variable(PropertyGroup):


 class Drawing(PropertyGroup):
-    name: StringProperty(name="Name", update=updateDrawingName)
-    camera: PointerProperty(name="Camera", type=bpy.types.Object)
+    ifc_definition_id: IntProperty(name="IFC Definition ID")
+    name: StringProperty(name="Name", update=update_drawing_name)
+    target_view: StringProperty(name="Target View")


 class Schedule(PropertyGroup):
@@ -213,9 +246,12 @@ class Sheet(PropertyGroup):
    def get_name(self):
        return self.get("name")

+    ifc_definition_id: IntProperty(name="IFC Definition ID")
+    identification: StringProperty(name="Identification")
    name: StringProperty(name="Name", get=get_name, set=set_name)
-    drawings: CollectionProperty(name="Drawings", type=Drawing)
-    active_drawing_index: IntProperty(name="Active Drawing Index")
+    is_sheet: BoolProperty(name="Is Sheet", default=False)
+    reference_type: StringProperty(name="Reference Type")
+    is_expanded: BoolProperty(name="Is Expanded", default=False)


 class DrawingStyle(PropertyGroup):
@@ -264,54 +300,52 @@ class RasterStyleProperty(enum.Enum):


 class DocProperties(PropertyGroup):
-    has_underlay: BoolProperty(name="Underlay", default=False)
-    has_linework: BoolProperty(name="Linework", default=True)
-    has_annotation: BoolProperty(name="Annotation", default=True)
    should_use_underlay_cache: BoolProperty(name="Use Underlay Cache", default=False)
    should_use_linework_cache: BoolProperty(name="Use Linework Cache", default=False)
    should_use_annotation_cache: BoolProperty(name="Use Annotation Cache", default=False)
    should_extract: BoolProperty(name="Should Extract", default=True)
+    is_editing_drawings: BoolProperty(name="Is Editing Drawings", default=False)
+    target_view: EnumProperty(
+        items=[
+            ("PLAN_VIEW", "Plan", ""),
+            ("ELEVATION_VIEW", "Elevation", ""),
+            ("SECTION_VIEW", "Section", ""),
+            ("REFLECTED_PLAN_VIEW", "RCP", ""),
+            ("MODEL_VIEW", "Model", ""),
+        ],
+        name="Target View",
+        default="PLAN_VIEW",
+        update=update_target_view,
+    )
+    location_hint: EnumProperty(items=get_location_hint, name="Location Hint")
    drawings: CollectionProperty(name="Drawings", type=Drawing)
-    active_drawing_index: IntProperty(name="Active Drawing Index", update=refreshActiveDrawingIndex)
+    active_drawing_id: IntProperty(name="Active Drawing Id")
+    active_drawing_index: IntProperty(name="Active Drawing Index")
    current_drawing_index: IntProperty(name="Current Drawing Index")
    schedules: CollectionProperty(name="Schedules", type=Schedule)
    active_schedule_index: IntProperty(name="Active Schedule Index")
    titleblock: EnumProperty(items=getTitleblocks, name="Titleblock", update=refreshTitleblocks)
+    is_editing_sheets: BoolProperty(name="Is Editing Sheets", default=False)
    sheets: CollectionProperty(name="Sheets", type=Sheet)
    active_sheet_index: IntProperty(name="Active Sheet Index")
    ifc_files: CollectionProperty(name="IFCs", type=StrProperty)
    drawing_styles: CollectionProperty(name="Drawing Styles", type=DrawingStyle)
    should_draw_decorations: BoolProperty(name="Should Draw Decorations", update=toggleDecorations)
    decorations_colour: FloatVectorProperty(
-        name="Decorations Colour", subtype="COLOR", default=(1, 0, 0, 1), min=0.0, max=1.0, size=4
+        name="Decorations Colour", subtype="COLOR", default=(1, 1, 1, 1), min=0.0, max=1.0, size=4
    )

    @property
    def active_schedule(self):
        return self.schedules[self.active_schedule_index]

-    @property
-    def active_drawing(self):
-        return self.drawings[self.active_drawing_index]
-
-    @property
-    def active_sheet(self):
-        return self.sheets[self.active_sheet_index]
-

 class BIMCameraProperties(PropertyGroup):
+    has_underlay: BoolProperty(name="Underlay", default=False, update=update_has_underlay)
+    has_linework: BoolProperty(name="Linework", default=True, update=update_has_linework)
+    has_annotation: BoolProperty(name="Annotation", default=True, update=update_has_annotation)
+    representation: StringProperty(name="Representation")
    view_name: StringProperty(name="View Name")
-    target_view: EnumProperty(
-        items=[
-            ("PLAN_VIEW", "PLAN_VIEW", ""),
-            ("ELEVATION_VIEW", "ELEVATION_VIEW", ""),
-            ("SECTION_VIEW", "SECTION_VIEW", ""),
-            ("REFLECTED_PLAN_VIEW", "REFLECTED_PLAN_VIEW", ""),
-            ("MODEL_VIEW", "MODEL_VIEW", ""),
-        ],
-        name="Target View",
-        default="PLAN_VIEW",
-    )
    diagram_scale: EnumProperty(items=get_diagram_scales, name="Drawing Scale", update=update_diagram_scale)
    custom_diagram_scale: StringProperty(name="Custom Scale", update=update_diagram_scale)
    raster_x: IntProperty(name="Raster X", default=1000)
@@ -332,8 +366,29 @@ class BIMCameraProperties(PropertyGroup):
    cut_objects_custom: StringProperty(name="Custom Cut")
    active_drawing_style_index: IntProperty(name="Active Drawing Style Index")

+    # For now, this JSON dump are all the parameters that determine a camera's "Block representation"
+    # By checking this, you will know whether or not the camera IFC representation needs to be refreshed
+    def update_representation(self, obj):
+        representation = json.dumps(
+            {
+                "matrix": [list(x) for x in obj.matrix_world],
+                "raster_x": self.raster_x,
+                "raster_y": self.raster_y,
+                "ortho_scale": obj.data.ortho_scale,
+                "clip_end": obj.data.clip_end,
+            }
+        )
+        if self.representation != representation:
+            self.representation = representation
+            return True
+        return False
+

 class BIMTextProperties(PropertyGroup):
+    is_editing: BoolProperty(name="Is Editing", default=False)
+    is_editing_product: BoolProperty(name="Is Editing Product", default=False)
+    attributes: CollectionProperty(name="Attributes", type=Attribute)
+    value: StringProperty(name="Value", default="TEXT")
    font_size: EnumProperty(
        items=[
            ("1.8", "1.8 - Small", ""),
@@ -342,6 +397,7 @@ class BIMTextProperties(PropertyGroup):
            ("5.0", "5.0 - Header", ""),
            ("7.0", "7.0 - Title", ""),
        ],
+        default="2.5",
        update=refreshFontSize,
        name="Font Size",
    )
@@ -354,5 +410,4 @@ class BIMTextProperties(PropertyGroup):
        update=refreshFontSize,
        name="Symbol",
    )
-    related_element: PointerProperty(name="Related Element", type=bpy.types.Object)
-    variables: CollectionProperty(name="Variables", type=Variable)
+    relating_product: PointerProperty(name="Relating Product", type=bpy.types.Object)
@@ -16,11 +16,12 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

-import xml.etree.ElementTree as ET
-import urllib.parse
-import pystache
-import ntpath
 import os
+import ntpath
+import pystache
+import urllib.parse
+import xml.etree.ElementTree as ET
+import blenderbim.tool as tool
 from shutil import copy
 from xml.dom import minidom

@@ -31,7 +32,7 @@ class SheetBuilder:
        self.scale = "NTS"

    def create(self, name, titleblock_name):
-        sheet_path = os.path.join(self.data_dir, f"{name}.svg")
+        sheet_path = os.path.join(self.data_dir, "sheets", f"{name}.svg")
        root = ET.Element("svg")
        root.attrib["xmlns"] = "http://www.w3.org/2000/svg"
        root.attrib["xmlns:xlink"] = "http://www.w3.org/1999/xlink"
@@ -59,11 +60,16 @@ class SheetBuilder:
        with open(sheet_path, "w") as f:
            f.write(minidom.parseString(ET.tostring(root)).toprettyxml(indent="    "))

-    def add_drawing(self, view_name, sheet_name):
-        sheet_path = os.path.join(self.data_dir, "sheets", sheet_name + ".svg")
-        view_path = os.path.join(self.data_dir, "diagrams", view_name + ".svg")
+    def add_drawing(self, drawing, sheet):
+        filename = drawing.Name
+        sheet_name = tool.Drawing.get_sheet_filename(sheet)
+        sheet_dir = os.path.join(self.data_dir, "sheets")
+        drawing_dir = os.path.join(self.data_dir, "diagrams")
+        sheet_path = os.path.join(sheet_dir, sheet_name + ".svg")
+        drawing_path = os.path.join(drawing_dir, filename + ".svg")
+        underlay_path = os.path.join(drawing_dir, filename + "-underlay.png")

-        if not os.path.isfile(view_path):
+        if not os.path.isfile(sheet_path):
            raise FileNotFoundError

        ET.register_namespace("", "http://www.w3.org/2000/svg")
@@ -72,7 +78,7 @@ class SheetBuilder:
        sheet_tree = ET.parse(sheet_path)
        sheet_root = sheet_tree.getroot()

-        view_tree = ET.parse(view_path)
+        view_tree = ET.parse(drawing_path)
        view_root = view_tree.getroot()

        # The view is placed into a group with a background image element.
@@ -80,26 +86,48 @@ class SheetBuilder:
        # here to accommodate browsers which do not nest images.
        view = ET.SubElement(sheet_root, "g")
        view.attrib["data-type"] = "drawing"
+        view.attrib["data-guid"] = drawing.GlobalId
        view_width = self.convert_to_mm(view_root.attrib.get("width"))
        view_height = self.convert_to_mm(view_root.attrib.get("height"))

-        background = ET.SubElement(view, "image")
-        background.attrib["xlink:href"] = "../diagrams/{}.png".format(view_name)
-        background.attrib["x"] = "30"
-        background.attrib["y"] = "30"
-        background.attrib["width"] = str(view_width)
-        background.attrib["height"] = str(view_height)
+        if os.path.isfile(underlay_path):
+            background = ET.SubElement(view, "image")
+            background.attrib["data-type"] = "background"
+            background.attrib["xlink:href"] = os.path.relpath(underlay_path, sheet_dir)
+            background.attrib["x"] = "30"
+            background.attrib["y"] = "30"
+            background.attrib["width"] = str(view_width)
+            background.attrib["height"] = str(view_height)

-        foreground = ET.SubElement(view, "image")
-        foreground.attrib["xlink:href"] = "../diagrams/{}.svg".format(view_name)
-        foreground.attrib["x"] = "30"
-        foreground.attrib["y"] = "30"
-        foreground.attrib["width"] = str(view_width)
-        foreground.attrib["height"] = str(view_height)
+        if os.path.isfile(drawing_path):
+            foreground = ET.SubElement(view, "image")
+            foreground.attrib["data-type"] = "foreground"
+            foreground.attrib["xlink:href"] = os.path.relpath(drawing_path, sheet_dir)
+            foreground.attrib["x"] = "30"
+            foreground.attrib["y"] = "30"
+            foreground.attrib["width"] = str(view_width)
+            foreground.attrib["height"] = str(view_height)

        self.add_view_title(30, view_height + 35, view)
        sheet_tree.write(sheet_path)

+    def remove_drawing(self, drawing, sheet):
+        sheet_name = tool.Drawing.get_sheet_filename(sheet)
+        sheet_dir = os.path.join(self.data_dir, "sheets")
+        sheet_path = os.path.join(sheet_dir, sheet_name + ".svg")
+
+        ET.register_namespace("", "http://www.w3.org/2000/svg")
+
+        sheet_tree = ET.parse(sheet_path)
+        sheet_root = sheet_tree.getroot()
+
+        for g in sheet_root.findall("{http://www.w3.org/2000/svg}g"):
+            if g.attrib["data-type"] == "drawing" and g.attrib["data-guid"] == drawing.GlobalId:
+                sheet_root.remove(g)
+                break
+
+        sheet_tree.write(sheet_path)
+
    def add_schedule(self, schedule_name, sheet_name):
        sheet_path = os.path.join(self.data_dir, "sheets", sheet_name + ".svg")
        view_path = os.path.join(self.data_dir, "schedules", schedule_name + ".svg")
@@ -132,13 +160,15 @@ class SheetBuilder:
        title_tree = ET.parse(os.path.join(self.data_dir, "templates", "view-title.svg"))
        title_root = title_tree.getroot()
        title = ET.SubElement(parent, "image")
+        title.attrib["data-type"] = "view-title"
        title.attrib["xlink:href"] = "../templates/view-title.svg"
        title.attrib["x"] = str(x)
        title.attrib["y"] = str(y)
        title.attrib["width"] = str(self.convert_to_mm(title_root.attrib.get("width")))
        title.attrib["height"] = str(self.convert_to_mm(title_root.attrib.get("height")))

-    def build(self, sheet_name):
+    def build(self, sheet):
+        sheet_name = tool.Drawing.get_sheet_filename(sheet)
        os.makedirs(os.path.join(self.data_dir, "build", sheet_name), exist_ok=True)

        sheet_path = os.path.join(self.data_dir, "sheets", f"{sheet_name}.svg")
@@ -149,48 +179,60 @@ class SheetBuilder:
        tree = ET.parse(sheet_path)
        root = tree.getroot()

-        titleblock = root.findall('{http://www.w3.org/2000/svg}g[@data-type="titleblock"]')[0]
-        image = titleblock.findall("{http://www.w3.org/2000/svg}image")[0]
-        titleblock.append(self.parse_embedded_svg(image, {"number": sheet_name, "revision": "A"}))
-        titleblock.remove(image)
-
-        self.group_number = 1
-        self.build_drawings(root.findall('{http://www.w3.org/2000/svg}g[@data-type="drawing"]'), sheet_name)
+        self.build_titleblock(root, sheet)
+        self.build_drawings(root, sheet)
        self.build_schedules(root.findall('{http://www.w3.org/2000/svg}g[@data-type="schedule"]'))

        with open(os.path.join(self.data_dir, "build", sheet_name, f"{sheet_name}.svg"), "wb") as output:
            tree.write(output)

-    def build_drawings(self, drawings, sheet_name):
-        for view in drawings:
+    def build_titleblock(self, root, sheet):
+        titleblock = root.findall('{http://www.w3.org/2000/svg}g[@data-type="titleblock"]')[0]
+        image = titleblock.findall("{http://www.w3.org/2000/svg}image")[0]
+        titleblock.append(self.parse_embedded_svg(image, sheet.get_info()))
+        titleblock.remove(image)
+
+    def build_drawings(self, root, sheet):
+        sheet_name = tool.Drawing.get_sheet_filename(sheet)
+        references = tool.Drawing.get_document_references(sheet)
+        drawing_references = {tool.Drawing.get_reference_element(r): r for r in  references}
+
+        for view in root.findall('{http://www.w3.org/2000/svg}g[@data-type="drawing"]'):
+            drawing = [d for d in drawing_references.keys() if d and d.GlobalId == view.attrib["data-guid"]][0]
+            reference = drawing_references[drawing]
+
            images = view.findall("{http://www.w3.org/2000/svg}image")
-            background = images[0]
-            foreground = images[1]
-            view_title = images[2]
-            self.scale = "NTS"

-            # Add foreground
-            view.append(self.parse_embedded_svg(foreground, {}))
+            background = None
+            foreground = None
+            view_title = None

-            # Add background
-            background_path = os.path.join(self.data_dir, "sheets", self.get_href(background))
+            for image in images:
+                if image.attrib["data-type"] == "background":
+                    background = image
+                elif image.attrib["data-type"] == "foreground":
+                    foreground = image
+                elif image.attrib["data-type"] == "view-title":
+                    view_title = image

-            copy(background_path, os.path.join(self.data_dir, "build", sheet_name))
+            if foreground is not None:
+                view.append(self.parse_embedded_svg(foreground, {}))

-            # Add view title
-            foreground_path = self.get_href(foreground)
-            view.append(
-                self.parse_embedded_svg(
-                    view_title,
-                    {"no": self.group_number, "name": ntpath.basename(foreground_path)[0:-4], "scale": self.scale},
-                )
-            )
+            if background is not None:
+                background_path = os.path.join(self.data_dir, "sheets", self.get_href(background))
+                copy(background_path, os.path.join(self.data_dir, "build", sheet_name))
+
+            if view_title is not None:
+                foreground_path = self.get_href(foreground)
+                data = reference.get_info()
+                if not data["Name"]:
+                    data["Name"] = ntpath.basename(foreground_path)[0:-4]
+                data["Scale"] = tool.Drawing.get_drawing_human_scale(drawing)
+                view.append(self.parse_embedded_svg(view_title, data))

            for image in images:
                view.remove(image)

-            self.group_number += 1
-
    def build_schedules(self, schedules):
        for group in schedules:
            images = group.findall("{http://www.w3.org/2000/svg}image")
@@ -203,15 +245,13 @@ class SheetBuilder:
            path = self.get_href(schedule)
            group.append(
                self.parse_embedded_svg(
-                    group_title, {"no": self.group_number, "name": ntpath.basename(path)[0:-4], "scale": self.scale}
+                    group_title, {"no": 1, "name": ntpath.basename(path)[0:-4], "scale": self.scale}
                )
            )

            for image in images:
                group.remove(image)

-            self.group_number += 1
-
    def get_href(self, element):
        return urllib.parse.unquote(element.attrib.get("{http://www.w3.org/1999/xlink}href"))

@@ -24,6 +24,9 @@ import pystache
 import xml.etree.ElementTree as ET
 import svgwrite
 import ifcopenshell
+import ifcopenshell.util.element
+import ifcopenshell.util.representation
+import blenderbim.tool as tool
 import blenderbim.bim.module.drawing.helper as helper
 import blenderbim.bim.module.drawing.annotation as annotation
 from mathutils import Vector
@@ -146,13 +149,10 @@ class SvgWriter:
            self.draw_dimension_annotations(obj)
        self.draw_measureit_arch_dimension_annotations()

-        if self.annotations.get("break_obj"):
-            self.draw_break_annotations(self.annotations["break_obj"])
-
        for grid_obj in self.annotations.get("grid_objs", []):
            matrix_world = grid_obj.matrix_world
+            classes = self.get_attribute_classes(grid_obj)
            for edge in grid_obj.data.edges:
-                classes = ["annotation", "grid"]
                v0_global = matrix_world @ grid_obj.data.vertices[edge.vertices[0]].co.xyz
                v1_global = matrix_world @ grid_obj.data.vertices[edge.vertices[1]].co.xyz
                v0 = self.project_point_onto_camera(v0_global)
@@ -165,10 +165,8 @@ class SvgWriter:
                        start=tuple(start * self.scale), end=tuple(end * self.scale), class_=" ".join(classes)
                    )
                )
-                line["marker-start"] = "url(#grid-marker)"
-                line["marker-end"] = "url(#grid-marker)"
                line["stroke-dasharray"] = "12.5, 3, 3, 3"
-                axis_tag = IfcStore.get_file().by_id(grid_obj.BIMObjectProperties.ifc_definition_id).AxisTag
+                axis_tag = tool.Ifc.get_entity(grid_obj).Name
                self.svg.add(
                    self.svg.text(
                        axis_tag,
@@ -199,66 +197,23 @@ class SvgWriter:
        self.draw_ifc_annotation()

        for obj in self.annotations.get("misc_objs", []):
-            self.draw_misc_annotation(obj, ["IfcAnnotation"])
+            self.draw_misc_annotation(obj)

        for obj_data in self.annotations.get("hidden_objs", []):
-            self.draw_line_annotation(obj_data, ["hidden"])
+            self.draw_line_annotation(obj_data)

        for obj_data in self.annotations.get("solid_objs", []):
-            self.draw_line_annotation(obj_data, ["solid"])
+            self.draw_line_annotation(obj_data)

-        if self.annotations.get("leader_obj"):
-            self.draw_line_annotation(self.annotations["leader_obj"], ["leader"])
+        self.draw_leader_annotations()

-        if self.annotations.get("plan_level_obj"):
-            matrix_world = self.annotations["plan_level_obj"].matrix_world
-            for spline in self.annotations["plan_level_obj"].data.splines:
-                classes = ["annotation", "plan-level"]
-                points = self.get_spline_points(spline)
-                projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in points]
-                d = " ".join(
-                    [
-                        "L {} {}".format((x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale)
-                        for p in projected_points
-                    ]
-                )
-                d = "M{}".format(d[1:])
-                path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))
-                path["marker-end"] = "url(#plan-level-marker)"
-                text_position = Vector(
-                    (
-                        (x_offset + projected_points[0].x) * self.scale,
-                        ((y_offset - projected_points[0].y) * self.scale) - 2.5,
-                    )
-                )
-                # TODO: allow metric to be configurable
-                rl = ((matrix_world @ points[0].co).xyz + self.annotations["plan_level_obj"].location).z
-                if bpy.context.scene.unit_settings.system == "IMPERIAL":
-                    rl = helper.format_distance(rl)
-                else:
-                    rl = "{:.3f}m".format(rl)
-                if projected_points[0].x > projected_points[-1].x:
-                    text_anchor = "end"
-                else:
-                    text_anchor = "start"
-                self.svg.add(
-                    self.svg.text(
-                        "RL +{}".format(rl),
-                        insert=tuple(text_position),
-                        **{
-                            "font-size": annotation.Annotator.get_svg_text_size(2.5),
-                            "font-family": "OpenGost Type B TT",
-                            "text-anchor": text_anchor,
-                            "alignment-baseline": "baseline",
-                            "dominant-baseline": "baseline",
-                        },
-                    )
-                )
+        for obj in self.annotations.get("plan_level_objs", []):
+            self.draw_plan_level_annotation(obj)

        if self.annotations.get("section_level_obj"):
            matrix_world = self.annotations["section_level_obj"].matrix_world
+            classes = self.get_attribute_classes(self.annotations["section_level_obj"])
            for spline in self.annotations["section_level_obj"].data.splines:
-                classes = ["annotation", "section-level"]
                points = self.get_spline_points(spline)
                projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in points]
                d = " ".join(
@@ -269,8 +224,6 @@ class SvgWriter:
                )
                d = "M{}".format(d[1:])
                path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))
-                path["marker-start"] = "url(#section-level-marker)"
-                path["stroke-dasharray"] = "12.5, 3, 3, 3"
                text_position = Vector(
                    (
                        (x_offset + projected_points[0].x) * self.scale,
@@ -299,8 +252,8 @@ class SvgWriter:

        if self.annotations.get("stair_obj"):
            matrix_world = self.annotations["stair_obj"].matrix_world
+            classes = self.get_attribute_classes(self.annotations["stair_obj"])
            for spline in self.annotations["stair_obj"].data.splines:
-                classes = ["annotation", "stair"]
                points = self.get_spline_points(spline)
                projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in points]
                d = " ".join(
@@ -327,7 +280,18 @@ class SvgWriter:
                        },
                    )
                )
-        self.draw_text_annotations()
+
+        for obj in self.annotations.get("elevation_objs", []):
+            self.draw_elevation_annotation(obj)
+
+        for obj in self.annotations.get("section_objs", []):
+            self.draw_section_annotation(obj)
+
+        for text_obj in self.annotations.get("text_objs", []):
+            self.draw_text_annotation(text_obj, text_obj.location)
+
+        if self.annotations.get("break_obj"):
+            self.draw_break_annotations(self.annotations["break_obj"])

    def draw_ifc_annotation(self):
        x_offset = self.raw_width / 2
@@ -349,13 +313,13 @@ class SvgWriter:
                    )
                )

-    def draw_misc_annotation(self, obj, classes):
+    def draw_misc_annotation(self, obj):
        # We have to decide whether this should come from Blender or from IFC.
        # For the moment, for convenience of experimenting with ideas, it comes
        # from Blender. In the future, it should probably come from IFC.
        if not isinstance(obj.data, bpy.types.Mesh):
            return
-        classes.extend(self.get_attribute_classes(obj))
+        classes = self.get_attribute_classes(obj)
        if len(obj.data.polygons) == 0:
            self.draw_edge_annotation(obj, classes)
            return
@@ -365,6 +329,7 @@ class SvgWriter:
        for polygon in obj.data.polygons:
            points = [obj.data.vertices[v] for v in polygon.vertices]
            projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in points]
+            projected_points.append(projected_points[0])
            d = " ".join(
                [
                    "L {} {}".format((x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale)
@@ -375,12 +340,12 @@ class SvgWriter:
            path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))

    def get_attribute_classes(self, obj):
-        classes = [obj.name.split("/")[0]]
-        for slot in obj.material_slots:
-            if slot.material:
-                classes.append("material-{}".format(re.sub("[^0-9a-zA-Z]+", "", slot.material.name)))
-        global_id = IfcStore.get_file().by_id(obj.BIMObjectProperties.ifc_definition_id).GlobalId
-        classes.append("globalid-{}".format(global_id))
+        element = tool.Ifc.get_entity(obj)
+        global_id = "GlobalId-{}".format(element.GlobalId)
+        predefined_type = "PredefinedType-" + self.canonicalise_class_name(
+            str(ifcopenshell.util.element.get_predefined_type(element))
+        )
+        classes = [global_id, element.is_a(), predefined_type]
        for attribute in self.annotations.get("attributes", []):
            result = self.get_obj_value(obj, attribute)
            if result:
@@ -389,6 +354,9 @@ class SvgWriter:
                )
        return classes

+    def canonicalise_class_name(self, name):
+        return re.sub("[^0-9a-zA-Z]+", "", name)
+
    def get_obj_value(self, obj, key):
        # This is a duplicate implementation of the IFC selector key in Blender
        # In the future if all this becomes purely IFC based this can be deleted
@@ -414,14 +382,14 @@ class SvgWriter:
            if result:
                return result.string_value

-    def draw_line_annotation(self, obj_data, classes):
+    def draw_line_annotation(self, obj_data):
        # TODO: properly scope these offsets
        x_offset = self.raw_width / 2
        y_offset = self.raw_height / 2

        obj, data = obj_data

-        classes.extend(["annotation"])
+        classes = self.get_attribute_classes(obj)
        matrix_world = obj.matrix_world

        if isinstance(data, bpy.types.Curve):
@@ -455,71 +423,183 @@ class SvgWriter:
                self.svg.line(start=tuple(start * self.scale), end=tuple(end * self.scale), class_=" ".join(classes))
            )

-    def draw_text_annotations(self):
+    def draw_leader_annotations(self):
+        for obj in self.annotations.get("leader_objs", []):
+            self.draw_line_annotation((obj, obj.data))
+            spline = obj.data.splines[0]
+            spline_points = spline.bezier_points if spline.bezier_points else spline.points
+            if spline_points:
+                position = obj.matrix_world @ spline_points[0].co.xyz
+            else:
+                position = Vector((0, 0, 0))
+            self.draw_text_annotation(obj, position)
+
+    def draw_section_annotation(self, obj):
        x_offset = self.raw_width / 2
        y_offset = self.raw_height / 2

-        for text_obj in self.annotations.get("text_objs", []):
-            text_position = self.project_point_onto_camera(text_obj.location)
-            text_position = Vector(((x_offset + text_position.x), (y_offset - text_position.y)))
+        self.draw_line_annotation((obj, obj.data))

-            local_x_axis = text_obj.matrix_world.to_quaternion() @ Vector((1, 0, 0))
-            projected_x_axis = self.project_point_onto_camera(text_obj.location + local_x_axis)
-            angle = math.degrees(
-                (Vector((x_offset + projected_x_axis.x, y_offset - projected_x_axis.y)) - text_position).angle_signed(
-                    Vector((1, 0))
-                )
-            )
+        v1 = self.project_point_onto_camera(obj.matrix_world @ Vector((0, 0, 0)))
+        v2 = self.project_point_onto_camera(obj.matrix_world @ Vector((0, 0, -1)))
+        angle = -math.degrees((v2 - v1).xy.angle_signed(Vector((0, 1))))

+        for vert in obj.data.vertices:
+            point = obj.matrix_world @ vert.co
+            symbol_position = self.project_point_onto_camera(point)
+            symbol_position = Vector(((x_offset + symbol_position.x), (y_offset - symbol_position.y)))
            transform = "rotate({}, {}, {})".format(
                angle,
-                (text_position * self.scale)[0],
-                (text_position * self.scale)[1],
+                (symbol_position * self.scale)[0],
+                (symbol_position * self.scale)[1],
            )

-            if text_obj.data.BIMTextProperties.symbol != "None":
-                self.svg.add(
-                    self.svg.use(
-                        "#{}".format(text_obj.data.BIMTextProperties.symbol), insert=tuple(text_position * self.scale)
-                    )
-                )
-
-            if text_obj.data.align_x == "CENTER":
-                text_anchor = "middle"
-            elif text_obj.data.align_x == "RIGHT":
-                text_anchor = "end"
-            else:
-                text_anchor = "start"
-
-            if text_obj.data.align_y == "CENTER":
-                alignment_baseline = "middle"
-            elif text_obj.data.align_y == "TOP":
-                alignment_baseline = "hanging"
-            else:
-                alignment_baseline = "baseline"
-
-            text_body = text_obj.data.body
-            if text_obj.name in self.annotations.get("template_variables", {}):
-                text_body = pystache.render(text_body, self.annotations["template_variables"][text_obj.name])
-
-            for line_number, text_line in enumerate(text_body.split("\n")):
-                self.svg.add(
-                    self.svg.text(
-                        text_line,
-                        insert=tuple((text_position * self.scale) + Vector((0, 3.5 * line_number))),
-                        class_=" ".join(self.get_attribute_classes(text_obj)),
-                        **{
-                            "font-size": annotation.Annotator.get_svg_text_size(
-                                text_obj.data.BIMTextProperties.font_size
-                            ),
-                            "font-family": "OpenGost Type B TT",
-                            "text-anchor": text_anchor,
-                            "alignment-baseline": alignment_baseline,
-                            "dominant-baseline": alignment_baseline,
-                            "transform": transform,
-                        },
-                    )
+            self.svg.add(
+                self.svg.use("#section-arrow", insert=tuple(symbol_position * self.scale), transform=transform)
+            )
+            self.svg.add(self.svg.use("#section-tag", insert=tuple(symbol_position * self.scale)))
+
+            reference_id, sheet_id = self.get_reference_and_sheet_id_from_annotation(tool.Ifc.get_entity(obj))
+            text_position = list(symbol_position * self.scale)
+            text_style = {
+                "font-size": annotation.Annotator.get_svg_text_size(2.5),
+                "font-family": "OpenGost Type B TT",
+                "text-anchor": "middle",
+                "alignment-baseline": "middle",
+                "dominant-baseline": "middle",
+            }
+            self.svg.add(self.svg.text(reference_id, insert=(text_position[0], text_position[1] - 2.5), **text_style))
+            self.svg.add(self.svg.text(sheet_id, insert=(text_position[0], text_position[1] + 2.5), **text_style))
+
+    def draw_elevation_annotation(self, obj):
+        x_offset = self.raw_width / 2
+        y_offset = self.raw_height / 2
+        symbol_position = self.project_point_onto_camera(obj.location)
+        symbol_position = Vector(((x_offset + symbol_position.x), (y_offset - symbol_position.y)))
+
+        v1 = self.project_point_onto_camera(obj.matrix_world @ Vector((0, 0, 0)))
+        v2 = self.project_point_onto_camera(obj.matrix_world @ Vector((0, 0, -1)))
+        angle = -math.degrees((v2 - v1).xy.angle_signed(Vector((0, 1))))
+
+        transform = "rotate({}, {}, {})".format(
+            angle,
+            (symbol_position * self.scale)[0],
+            (symbol_position * self.scale)[1],
+        )
+
+        self.svg.add(self.svg.use("#elevation-arrow", insert=tuple(symbol_position * self.scale), transform=transform))
+        self.svg.add(self.svg.use("#elevation-tag", insert=tuple(symbol_position * self.scale)))
+
+        reference_id, sheet_id = self.get_reference_and_sheet_id_from_annotation(tool.Ifc.get_entity(obj))
+        text_position = list(symbol_position * self.scale)
+        text_style = {
+            "font-size": annotation.Annotator.get_svg_text_size(2.5),
+            "font-family": "OpenGost Type B TT",
+            "text-anchor": "middle",
+            "alignment-baseline": "middle",
+            "dominant-baseline": "middle",
+        }
+        self.svg.add(self.svg.text(reference_id, insert=(text_position[0], text_position[1] - 2.5), **text_style))
+        self.svg.add(self.svg.text(sheet_id, insert=(text_position[0], text_position[1] + 2.5), **text_style))
+
+    def get_reference_and_sheet_id_from_annotation(self, element):
+        reference_id = "-"
+        sheet_id = "-"
+        drawing = tool.Drawing.get_annotation_element(element)
+        reference = tool.Drawing.get_drawing_reference(drawing)
+        if reference:
+            sheet = tool.Drawing.get_reference_sheet(reference)
+            if sheet:
+                if tool.Ifc.get_schema() == "IFC2X3":
+                    reference_id = reference.ItemReference or "-"
+                    sheet_id = sheet.DocumentId or "-"
+                else:
+                    reference_id = reference.Identification or "-"
+                    sheet_id = sheet.Identification or "-"
+                return (reference_id, sheet_id)
+        return ("-", "-")
+
+    def draw_text_annotation(self, text_obj, position):
+        x_offset = self.raw_width / 2
+        y_offset = self.raw_height / 2
+        element = tool.Ifc.get_entity(text_obj)
+        rep = ifcopenshell.util.representation.get_representation(element, "Plan", "Annotation")
+        text_literal = [i for i in rep.Items if i.is_a("IfcTextLiteral")][0]
+
+        text_position = self.project_point_onto_camera(position)
+        text_position = Vector(((x_offset + text_position.x), (y_offset - text_position.y)))
+
+        local_x_axis = text_obj.matrix_world.to_quaternion() @ Vector((1, 0, 0))
+        projected_x_axis = self.project_point_onto_camera(position + local_x_axis)
+        angle = math.degrees(
+            (Vector((x_offset + projected_x_axis.x, y_offset - projected_x_axis.y)) - text_position).angle_signed(
+                Vector((1, 0))
+            )
+        )
+
+        transform = "rotate({}, {}, {})".format(
+            angle,
+            (text_position * self.scale)[0],
+            (text_position * self.scale)[1],
+        )
+
+        if text_obj.BIMTextProperties.symbol != "None":
+            self.svg.add(
+                self.svg.use(f"#{text_obj.BIMTextProperties.symbol}", insert=tuple(text_position * self.scale))
+            )
+
+        if text_literal.BoxAlignment == "top-left":
+            alignment_baseline = "hanging"
+            text_anchor = "start"
+        elif text_literal.BoxAlignment == "top-middle":
+            alignment_baseline = "hanging"
+            text_anchor = "middle"
+        elif text_literal.BoxAlignment == "top-right":
+            alignment_baseline = "hanging"
+            text_anchor = "end"
+        elif text_literal.BoxAlignment == "middle-left":
+            alignment_baseline = "middle"
+            text_anchor = "start"
+        elif text_literal.BoxAlignment == "center":
+            alignment_baseline = "middle"
+            text_anchor = "middle"
+        elif text_literal.BoxAlignment == "middle-right":
+            alignment_baseline = "middle"
+            text_anchor = "end"
+        elif text_literal.BoxAlignment == "bottom-left":
+            alignment_baseline = "baseline"
+            text_anchor = "start"
+        elif text_literal.BoxAlignment == "bottom-middle":
+            alignment_baseline = "baseline"
+            text_anchor = "middle"
+        elif text_literal.BoxAlignment == "bottom-right":
+            alignment_baseline = "baseline"
+            text_anchor = "end"
+
+        literal = text_literal.Literal
+
+        product = tool.Drawing.get_text_product(element)
+        selector = ifcopenshell.util.selector.Selector
+        variables = {}
+        for variable in re.findall("{{.*?}}", literal):
+            literal = literal.replace(variable, selector.get_element_value(product, variable[2:-2]) or "")
+
+        for line_number, text_line in enumerate(literal.replace("\\n", "\n").split("\n")):
+            self.svg.add(
+                self.svg.text(
+                    text_line,
+                    insert=tuple((text_position * self.scale) + Vector((0, 3.5 * line_number))),
+                    class_=" ".join(self.get_attribute_classes(text_obj)),
+                    **{
+                        "font-size": annotation.Annotator.get_svg_text_size(text_obj.BIMTextProperties.font_size),
+                        "font-family": "OpenGost Type B TT",
+                        "text-anchor": text_anchor,
+                        "alignment-baseline": alignment_baseline,
+                        "dominant-baseline": alignment_baseline,
+                        "transform": transform,
+                    },
                )
+            )

    def draw_break_annotations(self, break_obj):
        x_offset = self.raw_width / 2
@@ -549,7 +629,54 @@ class SvgWriter:
            d = "M{}".format(d[1:])
            path = self.svg.add(self.svg.path(d=d, class_=" ".join(["breakline"])))

+    def draw_plan_level_annotation(self, obj):
+        x_offset = self.raw_width / 2
+        y_offset = self.raw_height / 2
+        matrix_world = obj.matrix_world
+        classes = self.get_attribute_classes(obj)
+        for spline in obj.data.splines:
+            points = self.get_spline_points(spline)
+            projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in points]
+            d = " ".join(
+                [
+                    "L {} {}".format((x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale)
+                    for p in projected_points
+                ]
+            )
+            d = "M{}".format(d[1:])
+            path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))
+            text_position = Vector(
+                (
+                    (x_offset + projected_points[0].x) * self.scale,
+                    ((y_offset - projected_points[0].y) * self.scale) - 2.5,
+                )
+            )
+            # TODO: allow metric to be configurable
+            rl = ((matrix_world @ points[0].co).xyz + obj.location).z
+            if bpy.context.scene.unit_settings.system == "IMPERIAL":
+                rl = helper.format_distance(rl)
+            else:
+                rl = "{:.3f}m".format(rl)
+            if projected_points[0].x > projected_points[-1].x:
+                text_anchor = "end"
+            else:
+                text_anchor = "start"
+            self.svg.add(
+                self.svg.text(
+                    "RL +{}".format(rl),
+                    insert=tuple(text_position),
+                    **{
+                        "font-size": annotation.Annotator.get_svg_text_size(2.5),
+                        "font-family": "OpenGost Type B TT",
+                        "text-anchor": text_anchor,
+                        "alignment-baseline": "baseline",
+                        "dominant-baseline": "baseline",
+                    },
+                )
+            )
+
    def draw_dimension_annotations(self, dimension_obj, text_override=None):
+        classes = self.get_attribute_classes(dimension_obj)
        matrix_world = dimension_obj.matrix_world
        for spline in dimension_obj.data.splines:
            points = self.get_spline_points(spline)
@@ -558,7 +685,7 @@ class SvgWriter:
                    continue
                v0_global = matrix_world @ points[i].co.xyz
                v1_global = matrix_world @ points[i + 1].co.xyz
-                self.draw_dimension_annotation(v0_global, v1_global, text_override)
+                self.draw_dimension_annotation(v0_global, v1_global, classes, text_override)

    def draw_measureit_arch_dimension_annotations(self):
        try:
@@ -568,10 +695,11 @@ class SvgWriter:
        except:
            return
        for coord in coords:
-            self.draw_dimension_annotation(Vector(coord[0]), Vector(coord[1]))
+            self.draw_dimension_annotation(
+                Vector(coord[0]), Vector(coord[1]), ["IfcAnnotation", "PredefinedType-DIMENSION"]
+            )

-    def draw_dimension_annotation(self, v0_global, v1_global, text_override=None):
-        classes = ["annotation", "dimension"]
+    def draw_dimension_annotation(self, v0_global, v1_global, classes, text_override=None):
        x_offset = self.raw_width / 2
        y_offset = self.raw_height / 2
        v0 = self.project_point_onto_camera(v0_global)
@@ -593,8 +721,6 @@ class SvgWriter:
        line = self.svg.add(
            self.svg.line(start=tuple(start * self.scale), end=tuple(end * self.scale), class_=" ".join(classes))
        )
-        line["marker-start"] = "url(#dimension-marker-start)"
-        line["marker-end"] = "url(#dimension-marker-end)"
        if text_override is not None:
            text = text_override
        else:
@@ -613,6 +739,7 @@ class SvgWriter:
        )

    def project_point_onto_camera(self, point):
+        # TODO is this needlessly complex?
        return self.camera.matrix_world.inverted() @ geometry.intersect_line_plane(
            point.xyz,
            point.xyz - Vector(self.camera_projection),
@@ -17,7 +17,10 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

 import bpy
+import blenderbim.bim.helper
+import blenderbim.tool as tool
 from bpy.types import Panel
+from blenderbim.bim.module.drawing.data import TextData, SheetsData, DrawingsData


 class BIM_PT_camera(Panel):
@@ -44,13 +47,13 @@ class BIM_PT_camera(Panel):

        col = layout.column(align=True)
        row = col.row(align=True)
-        row.prop(dprops, "has_underlay", icon="OUTLINER_OB_IMAGE")
+        row.prop(props, "has_underlay", icon="OUTLINER_OB_IMAGE")
        row.prop(dprops, "should_use_underlay_cache", text="", icon="FILE_REFRESH")
        row = col.row(align=True)
-        row.prop(dprops, "has_linework", icon="IMAGE_DATA")
+        row.prop(props, "has_linework", icon="IMAGE_DATA")
        row.prop(dprops, "should_use_linework_cache", text="", icon="FILE_REFRESH")
        row = col.row(align=True)
-        row.prop(dprops, "has_annotation", icon="MOD_EDGESPLIT")
+        row.prop(props, "has_annotation", icon="MOD_EDGESPLIT")
        row.prop(dprops, "should_use_annotation_cache", text="", icon="FILE_REFRESH")

        row = layout.row()
@@ -64,9 +67,6 @@ class BIM_PT_camera(Panel):
        row = layout.row()
        row.operator("bim.resize_text")

-        row = layout.row()
-        row.prop(props, "target_view")
-
        row = layout.row()
        row.prop(props, "cut_objects")
        if props.cut_objects == "CUSTOM":
@@ -146,44 +146,62 @@ class BIM_PT_drawing_underlay(Panel):


 class BIM_PT_drawings(Panel):
-    bl_label = "SVG Drawings"
+    bl_label = "Drawings"
    bl_idname = "BIM_PT_drawings"
-    bl_space_type = "PROPERTIES"
-    bl_region_type = "WINDOW"
-    bl_context = "output"
+    bl_space_type = "VIEW_3D"
+    bl_region_type = "UI"
+    bl_category = "BIM Documentation"

    def draw(self, context):
-        layout = self.layout
-        layout.use_property_split = True
-        props = context.scene.DocProperties
+        if not DrawingsData.is_loaded:
+            DrawingsData.load()

-        row = layout.row(align=True)
-        row.operator("bim.add_drawing")
-        row.operator("bim.refresh_drawing_list", icon="FILE_REFRESH", text="")
+        self.props = context.scene.DocProperties

-        if props.drawings:
-            if props.active_drawing_index < len(props.drawings):
+        if not self.props.is_editing_drawings:
+            row = self.layout.row(align=True)
+            row.label(text=f"{DrawingsData.data['total_drawings']} Drawings Found", icon="IMAGE_DATA")
+            row.operator("bim.load_drawings", text="", icon="IMPORT")
+            return
+
+        row = self.layout.row(align=True)
+        row.prop(self.props, "target_view", text="")
+        row.prop(self.props, "location_hint", text="")
+        row.operator("bim.add_drawing", text="", icon="ADD")
+        row.operator("bim.disable_editing_drawings", text="", icon="CANCEL")
+
+        if self.props.drawings:
+            if self.props.active_drawing_index < len(self.props.drawings):
+                active_drawing = self.props.drawings[self.props.active_drawing_index]
+                row = self.layout.row(align=True)
+                row.alignment = "RIGHT"
                op = row.operator("bim.open_view", icon="URL", text="")
-                op.view = props.active_drawing.name
-                row.operator("bim.remove_drawing", icon="X", text="").index = props.active_drawing_index
-            layout.template_list("BIM_UL_drawinglist", "", props, "drawings", props, "active_drawing_index")
+                op.view = active_drawing.name
+                op = row.operator("bim.activate_view", icon="OUTLINER_OB_CAMERA", text="")
+                op.drawing = active_drawing.ifc_definition_id
+                row.operator("bim.create_drawing", text="", icon="OUTPUT")
+                row.operator("bim.remove_drawing", icon="X", text="").drawing = active_drawing.ifc_definition_id
+            self.layout.template_list(
+                "BIM_UL_drawinglist", "", self.props, "drawings", self.props, "active_drawing_index"
+            )

-        row = layout.row()
-        row.operator("bim.add_ifc_file")
+        # Commented out until federated drawing generation is rebuilt
+        # row = self.layout.row()
+        # row.operator("bim.add_ifc_file")

-        for index, ifc_file in enumerate(props.ifc_files):
-            row = layout.row(align=True)
-            row.prop(ifc_file, "name", text="IFC #{}".format(index + 1))
-            row.operator("bim.select_doc_ifc_file", icon="FILE_FOLDER", text="").index = index
-            row.operator("bim.remove_ifc_file", icon="X", text="").index = index
+        # for index, ifc_file in enumerate(self.props.ifc_files):
+        #     row = self.layout.row(align=True)
+        #     row.prop(ifc_file, "name", text="IFC #{}".format(index + 1))
+        #     row.operator("bim.select_doc_ifc_file", icon="FILE_FOLDER", text="").index = index
+        #     row.operator("bim.remove_ifc_file", icon="X", text="").index = index


 class BIM_PT_schedules(Panel):
-    bl_label = "ODS Schedules"
+    bl_label = "Schedules"
    bl_idname = "BIM_PT_schedules"
-    bl_space_type = "PROPERTIES"
-    bl_region_type = "WINDOW"
-    bl_context = "output"
+    bl_space_type = "VIEW_3D"
+    bl_region_type = "UI"
+    bl_category = "BIM Documentation"

    def draw(self, context):
        layout = self.layout
@@ -205,150 +223,192 @@ class BIM_PT_schedules(Panel):


 class BIM_PT_sheets(Panel):
-    bl_label = "SVG Sheets"
+    bl_label = "Sheets"
    bl_idname = "BIM_PT_sheets"
-    bl_space_type = "PROPERTIES"
-    bl_region_type = "WINDOW"
-    bl_context = "output"
+    bl_space_type = "VIEW_3D"
+    bl_region_type = "UI"
+    bl_category = "BIM Documentation"

    def draw(self, context):
-        layout = self.layout
-        props = context.scene.DocProperties
+        if not SheetsData.is_loaded:
+            SheetsData.load()

-        row = layout.row(align=True)
-        row.prop(props, "titleblock", text="")
-        row.operator("bim.add_sheet")
+        self.props = context.scene.DocProperties

-        if props.sheets:
+        if not self.props.is_editing_sheets:
+            row = self.layout.row(align=True)
+            row.label(text=f"{SheetsData.data['total_sheets']} Sheets Found", icon="FILE")
+            row.operator("bim.load_sheets", text="", icon="IMPORT")
+            return
+
+        row = self.layout.row(align=True)
+        row.prop(self.props, "titleblock", text="")
+        row.operator("bim.add_sheet", text="", icon="ADD")
+        row.operator("bim.disable_editing_sheets", text="", icon="CANCEL")
+
+        if self.props.sheets and self.props.active_sheet_index < len(self.props.sheets):
+            active_sheet = self.props.sheets[self.props.active_sheet_index]
+            row = self.layout.row(align=True)
+            row.alignment = "RIGHT"
            row.operator("bim.open_sheet", icon="URL", text="")
-            row.operator("bim.remove_sheet", icon="X", text="").index = props.active_sheet_index
+            row.operator("bim.add_drawing_to_sheet", icon="IMAGE_PLANE", text="")
+            row.operator("bim.add_schedule_to_sheet", icon="PRESET_NEW", text="")
+            row.operator("bim.create_sheets", icon="FILE_REFRESH", text="")
+            if active_sheet.is_sheet:
+                row.operator("bim.remove_sheet", icon="X", text="").sheet = active_sheet.ifc_definition_id
+            else:
+                op = row.operator("bim.remove_drawing_from_sheet", icon="X", text="")
+                op.reference = active_sheet.ifc_definition_id

-            layout.template_list("BIM_UL_generic", "", props, "sheets", props, "active_sheet_index")
-
-        row = layout.row(align=True)
-        row.operator("bim.add_drawing_to_sheet")
-        row.operator("bim.add_schedule_to_sheet")
-        row = layout.row()
-        row.operator("bim.create_sheets")
+        self.layout.template_list("BIM_UL_sheets", "", self.props, "sheets", self.props, "active_sheet_index")


 class BIM_PT_text(Panel):
-    bl_label = "Text Paper Space"
+    bl_label = "IFC Text"
    bl_idname = "BIM_PT_text"
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
-    bl_context = "data"
+    bl_context = "object"

    @classmethod
    def poll(cls, context):
-        return type(context.curve) is bpy.types.TextCurve
+        if not tool.Ifc.get() or not context.active_object:
+            return
+        element = tool.Ifc.get_entity(context.active_object)
+        if not element:
+            return
+        return element.is_a("IfcAnnotation") and element.ObjectType in ["TEXT", "TEXT_LEADER"]

    def draw(self, context):
-        layout = self.layout
-        layout.use_property_split = True
-        props = context.active_object.data.BIMTextProperties
+        if not TextData.is_loaded:
+            TextData.load()

-        row = layout.row()
-        row.operator("bim.propagate_text_data")
+        props = context.active_object.BIMTextProperties

-        row = layout.row()
+        if props.is_editing:
+            row = self.layout.row(align=True)
+            row.operator("bim.edit_text", icon="CHECKMARK")
+            row.operator("bim.disable_editing_text", icon="CANCEL", text="")
+            blenderbim.bim.helper.draw_attributes(props.attributes, self.layout)
+        else:
+            row = self.layout.row()
+            row.operator("bim.enable_editing_text", icon="GREASEPENCIL")
+
+            for attribute in TextData.data["attributes"]:
+                row = self.layout.row(align=True)
+                row.label(text=attribute["name"])
+                row.label(text=attribute["value"])
+
+        if props.is_editing_product:
+            row = self.layout.row(align=True)
+            row.prop(props, "relating_product", text="")
+            row.operator("bim.edit_text_product", icon="CHECKMARK", text="")
+            row.operator("bim.disable_editing_text_product", icon="CANCEL", text="")
+        else:
+            row = self.layout.row(align=True)
+            row.label(text=TextData.data["relating_product"] or "No Relating Product", icon="OBJECT_DATA")
+            row.operator("bim.enable_editing_text_product", icon="GREASEPENCIL", text="")
+
+        row = self.layout.row()
        row.prop(props, "font_size")
-        row = layout.row()
+        row = self.layout.row()
        row.prop(props, "symbol")
-        row = layout.row()
-        row.prop(props, "related_element")
-
-        row = layout.row()
-        row.operator("bim.add_variable")
-
-        for index, variable in enumerate(props.variables):
-            row = layout.row(align=True)
-            row.prop(variable, "name")
-            row.operator("bim.remove_variable", icon="X", text="").index = index
-            row = layout.row()
-            row.prop(variable, "prop_key")


 class BIM_PT_annotation_utilities(Panel):
    bl_idname = "BIM_PT_annotation_utilities"
    bl_label = "Annotation"
-    bl_options = {"DEFAULT_CLOSED"}
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"
-    bl_category = "BlenderBIM"
+    bl_category = "BIM Documentation"

    def draw(self, context):
        layout = self.layout

-        row = layout.row(align=True)
-        row.operator("bim.clean_wireframes")
-        row = layout.row(align=True)
-        row.operator("bim.add_grid")
-        row = layout.row(align=True)
-        row.operator("bim.add_sections_annotations")
+        self.props = context.scene.DocProperties

        row = layout.row(align=True)
        op = row.operator("bim.add_annotation", text="Dim", icon="ARROW_LEFTRIGHT")
-        op.obj_name = "Dimension"
+        op.object_type = "DIMENSION"
        op.data_type = "curve"
        op = row.operator("bim.add_annotation", text="Dim (Eq)", icon="ARROW_LEFTRIGHT")
-        op.obj_name = "Equal"
+        op.object_type = "EQUAL_DIMENSION"
        op.data_type = "curve"

        row = layout.row(align=True)
        op = row.operator("bim.add_annotation", text="Text", icon="SMALL_CAPS")
-        op.data_type = "text"
+        op.object_type = "TEXT"
+        op.data_type = "empty"
        op = row.operator("bim.add_annotation", text="Leader", icon="TRACKING_BACKWARDS")
-        op.obj_name = "Leader"
+        op.object_type = "TEXT_LEADER"
        op.data_type = "curve"

        row = layout.row(align=True)
        op = row.operator("bim.add_annotation", text="Stair Arrow", icon="SCREEN_BACK")
-        op.obj_name = "Stair"
+        op.object_type = "STAIR_ARROW"
        op.data_type = "curve"
        op = row.operator("bim.add_annotation", text="Hidden", icon="CON_TRACKTO")
-        op.obj_name = "Hidden"
+        op.object_type = "HIDDEN_LINE"
        op.data_type = "mesh"

        row = layout.row(align=True)
        op = row.operator("bim.add_annotation", text="Level (Plan)", icon="SORTBYEXT")
-        op.obj_name = "Plan Level"
+        op.object_type = "PLAN_LEVEL"
        op.data_type = "curve"
        op = row.operator("bim.add_annotation", text="Level (Section)", icon="TRIA_DOWN")
-        op.obj_name = "Section Level"
+        op.object_type = "SECTION_LEVEL"
        op.data_type = "curve"

        row = layout.row(align=True)
        op = row.operator("bim.add_annotation", text="Breakline", icon="FCURVE")
-        op.obj_name = "Break"
+        op.object_type = "BREAKLINE"
        op.data_type = "mesh"
        op = row.operator("bim.add_annotation", text="Misc", icon="MESH_MONKEY")
-        op.obj_name = "Misc"
+        op.object_type = "MISC"
        op.data_type = "mesh"

-        props = context.scene.DocProperties
-
        row = layout.row(align=True)
-        row.operator("bim.add_drawing")
-        row.operator("bim.refresh_drawing_list", icon="FILE_REFRESH", text="")
-
-        if props.drawings:
-            if props.active_drawing_index < len(props.drawings):
-                op = row.operator("bim.open_view", icon="URL", text="")
-                op.view = props.active_drawing.name
-                row.operator("bim.remove_drawing", icon="X", text="").index = props.active_drawing_index
-            layout.template_list("BIM_UL_drawinglist", "", props, "drawings", props, "active_drawing_index")
-
-        layout.prop(props, "should_draw_decorations")
-        layout.prop(props, "decorations_colour")
+        row.prop(self.props, "should_draw_decorations", text="Viewport Annotations")


 class BIM_UL_drawinglist(bpy.types.UIList):
    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
        if item:
            row = layout.row(align=True)
-            row.prop(item, "name", text="", emboss=False)
-            op = row.operator("bim.open_view_camera", icon="OUTLINER_OB_CAMERA", text="")
-            op.view_name = item.name
+            icon = "UV_FACESEL"
+            if item.target_view == "ELEVATION_VIEW":
+                icon = "UV_VERTEXSEL"
+            elif item.target_view == "SECTION_VIEW":
+                icon = "UV_EDGESEL"
+            elif item.target_view == "REFLECTED_PLAN_VIEW":
+                icon = "XRAY"
+            elif item.target_view == "MODEL_VIEW":
+                icon = "SNAP_VOLUME"
+            row.prop(item, "name", text="", icon=icon, emboss=False)
+        else:
+            layout.label(text="", translate=False)
+
+
+class BIM_UL_sheets(bpy.types.UIList):
+    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
+        if item:
+            row = layout.row(align=True)
+
+            if item.is_sheet:
+                if item.is_expanded:
+                    row.operator(
+                        "bim.contract_sheet", text="", emboss=False, icon="DISCLOSURE_TRI_DOWN"
+                    ).sheet = item.ifc_definition_id
+                else:
+                    row.operator(
+                        "bim.expand_sheet", text="", emboss=False, icon="DISCLOSURE_TRI_RIGHT"
+                    ).sheet = item.ifc_definition_id
+            else:
+                row.label(text="", icon="BLANK1")
+                if item.reference_type == "DRAWING":
+                    row.label(text="", icon="IMAGE_DATA")
+
+            name = "{} - {}".format(item.identification or "X", item.name or "Unnamed")
+            row.label(text=name)
        else:
            layout.label(text="", translate=False)
@@ -25,6 +25,7 @@ classes = (
    operator.EditObjectPlacement,
    operator.GetRepresentationIfcParameters,
    operator.OverrideDelete,
+    operator.OverrideOutlinerDelete,
    operator.OverrideDuplicateMove,
    operator.OverrideDuplicateMoveLinked,
    operator.OverridePasteBuffer,
@@ -40,6 +40,7 @@ class RepresentationsData:
    def representations(cls):
        results = []
        element = tool.Ifc.get_entity(bpy.context.active_object)
+        representations = []
        if element.is_a("IfcProduct") and element.Representation:
            representations = element.Representation.Representations
        elif element.is_a("IfcTypeProduct"):
@@ -49,15 +50,17 @@ class RepresentationsData:
            if representation_type == "MappedRepresentation":
                representation_type = representation.Items[0].MappingSource.MappedRepresentation.RepresentationType
                representation_type += "*"
-            results.append(
-                {
-                    "id": representation.id(),
-                    "ContextType": representation.ContextOfItems.ContextType,
-                    "ContextIdentifier": representation.ContextOfItems.ContextIdentifier,
-                    "TargetView": representation.ContextOfItems.TargetView,
-                    "RepresentationType": representation_type,
-                }
-            )
+            data = {
+                "id": representation.id(),
+                "ContextType": representation.ContextOfItems.ContextType or "",
+                "ContextIdentifier": "",
+                "TargetView": "",
+                "RepresentationType": representation_type or "",
+            }
+            if representation.ContextOfItems.is_a("IfcGeometricRepresentationSubContext"):
+                data["ContextIdentifier"] = representation.ContextOfItems.ContextIdentifier or ""
+                data["TargetView"] = representation.ContextOfItems.TargetView or ""
+            results.append(data)
        return results


@@ -22,7 +22,7 @@ import mathutils
 import ifcopenshell
 import ifcopenshell.util.unit
 from math import pi
-from mathutils import Vector, Matrix
+from mathutils import Vector, Matrix, geometry


 class Helper:
@@ -215,6 +215,95 @@ class Helper:

        return {"profile": outer_loop, "inner_curves": inner_loops, "extrusion": extrusion}

+    # An arbitrary face with voids is similar to a profile with voids for extrusion.
+    # Before we begin we check that all faces are coplanar instead of finding suitable face.
+    # Then we process the same way.
+    # Only 2 parameters are returned as there is no extrusion.
+    def auto_detect_curve_bounded_plane(self, mesh, tolerance=0.001):
+        bm = bmesh.new()
+        bm.from_mesh(mesh)
+        bmesh.ops.dissolve_limit(bm, angle_limit=pi / 180 * 1, verts=bm.verts, edges=bm.edges)
+
+        bm.faces.ensure_lookup_table()
+        faces = bm.faces
+        normal = faces[0].normal
+        point = faces[0].verts[0].co
+        for face in faces:
+            pt_f = face.verts[0].co
+            if (
+                normal.dot(face.normal) < 1 - tolerance
+                or abs(geometry.distance_point_to_plane(pt_f, point, normal)) > tolerance
+            ):
+                raise ValueError("All faces must be coplanar and have same orientation")
+
+        loop_edges = set()
+        for face in faces:
+            potential_edges = set(face.edges)
+            for face2 in faces:
+                if face == face2:
+                    continue
+                potential_edges -= set(face2.edges)
+            loop_edges |= potential_edges
+
+        # Create loops from edges
+        loops = []
+        while loop_edges:
+            edge = loop_edges.pop()
+            loop = [edge]
+            has_found_connected_edge = True
+            while has_found_connected_edge:
+                has_found_connected_edge = False
+                for edge in loop_edges.copy():
+                    edge_verts = set(edge.verts)
+                    if edge_verts & set(loop[0].verts):
+                        loop.insert(0, edge)
+                        loop_edges.remove(edge)
+                        has_found_connected_edge = True
+                    elif edge_verts & set(loop[-1].verts):
+                        loop.append(edge)
+                        loop_edges.remove(edge)
+                        has_found_connected_edge = True
+            loops.append(loop)
+
+        # Determine outer loop
+        max_area = 0
+        outer_loop = None
+        inner_loops = []
+
+        for loop in loops:
+            loop_vertices = []
+            total_edges = len(loop)
+            for i, edge in enumerate(loop):
+                if i + 1 == total_edges and edge.verts[0] in loop[i - 1].verts:
+                    loop_vertices.append(edge.verts[0])
+                elif i + 1 == total_edges and edge.verts[1] in loop[i - 1].verts:
+                    loop_vertices.append(edge.verts[1])
+                elif edge.verts[0] in loop[i + 1].verts:
+                    loop_vertices.append(edge.verts[1])
+                elif edge.verts[1] in loop[i + 1].verts:
+                    loop_vertices.append(edge.verts[0])
+
+            loop_bm = bmesh.new()
+            for vert in loop_vertices:
+                loop_bm.verts.new(vert.co)
+            face = loop_bm.faces.new(loop_bm.verts)
+
+            loop_vertex_indices = [v.index for v in loop_vertices]
+            face_area = face.calc_area()
+            if face_area > max_area:
+                max_area = face_area
+                outer_loop = loop_vertex_indices
+            inner_loops.append(loop_vertex_indices)
+            loop_bm.free()
+
+        inner_loops.remove(outer_loop)
+
+        bm.to_mesh(mesh)
+        mesh.update()
+        bm.free()
+
+        return {"outer_curve": outer_loop, "inner_curves": inner_loops}
+
    # An extrusion edge is an edge that shares a single vertex with a profile
    # face and is not on the plane of the face.
    def detect_extrusion_edge(self, bm, profile_face):
@@ -30,12 +30,13 @@ import blenderbim.core.style
 import blenderbim.core.root
 import blenderbim.tool as tool
 import blenderbim.bim.handler
-from blenderbim.bim.ifc import IfcStore
-from blenderbim.bim import import_ifc
+from mathutils import Vector
 from ifcopenshell.api.geometry.data import Data
 from ifcopenshell.api.context.data import Data as ContextData
 from ifcopenshell.api.void.data import Data as VoidData
-from mathutils import Vector
+from blenderbim.bim import import_ifc
+from blenderbim.bim.ifc import IfcStore
+from blenderbim.bim.module.root.prop import get_contexts


 class Operator:
@@ -54,7 +55,7 @@ class EditObjectPlacement(bpy.types.Operator, Operator):
    def _execute(self, context):
        objs = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
        for obj in objs:
-            core.edit_object_placement(tool.Ifc, tool.Surveyor, obj=obj)
+            core.edit_object_placement(tool.Ifc, tool.Geometry, tool.Surveyor, obj=obj)


 class AddRepresentation(bpy.types.Operator, Operator):
@@ -67,7 +68,9 @@ class AddRepresentation(bpy.types.Operator, Operator):
    profile_set_usage: bpy.props.IntProperty()

    def _execute(self, context):
-        ifc_context = self.context_id or int(context.scene.BIMProperties.contexts or "0") or None
+        ifc_context = self.context_id
+        if not ifc_context and get_contexts(self, context):
+            ifc_context = int(context.scene.BIMRootProperties.contexts or "0") or None
        if ifc_context:
            ifc_context = tool.Ifc.get().by_id(ifc_context)
        obj = bpy.data.objects.get(self.obj) if self.obj else context.active_object
@@ -81,16 +84,6 @@ class AddRepresentation(bpy.types.Operator, Operator):
            ifc_representation_class=self.ifc_representation_class,
            profile_set_usage=tool.Ifc.get().by_id(self.profile_set_usage) if self.profile_set_usage else None,
        )
-        Data.load(tool.Ifc.get(), obj.BIMObjectProperties.ifc_definition_id)
-        element = tool.Ifc.get_entity(obj)
-        if element.is_a("IfcTypeProduct"):
-            if tool.Ifc.get_schema() == "IFC2X3":
-                types = element.ObjectTypeOf
-            else:
-                types = element.Types
-            if types:
-                for element in types[0].RelatedObjects:
-                    Data.load(tool.Ifc.get(), element.id())


 class SwitchRepresentation(bpy.types.Operator, Operator):
@@ -111,6 +104,7 @@ class SwitchRepresentation(bpy.types.Operator, Operator):
            should_reload=self.should_reload,
            enable_dynamic_voids=self.disable_opening_subtractions,
            is_global=self.should_switch_all_meshes,
+            should_sync_changes_first=True,
        )


@@ -118,37 +112,15 @@ class RemoveRepresentation(bpy.types.Operator, Operator):
    bl_idname = "bim.remove_representation"
    bl_label = "Remove Representation"
    bl_options = {"REGISTER", "UNDO"}
-    obj: bpy.props.StringProperty()
    representation_id: bpy.props.IntProperty()

    def _execute(self, context):
-        self.file = IfcStore.get_file()
-        representation = self.file.by_id(self.representation_id)
-        obj = bpy.data.objects.get(self.obj) if self.obj else context.active_object
-        is_mapped_representation = representation.RepresentationType == "MappedRepresentation"
-        if is_mapped_representation:
-            mesh_name = "{}/{}".format(
-                representation.ContextOfItems.id(), representation.Items[0].MappingSource.MappedRepresentation.id()
-            )
-        else:
-            mesh_name = "{}/{}".format(representation.ContextOfItems.id(), representation.id())
-        mesh = bpy.data.meshes.get(mesh_name)
-        if mesh:
-            if obj.data == mesh:
-                # TODO we can do better than this
-                void_mesh = bpy.data.meshes.get("Void")
-                if not void_mesh:
-                    void_mesh = bpy.data.meshes.new("Void")
-                obj.data = void_mesh
-            if not is_mapped_representation:
-                bpy.data.meshes.remove(mesh)
-        product = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
-        ifcopenshell.api.run(
-            "geometry.unassign_representation", self.file, **{"product": product, "representation": representation}
+        core.remove_representation(
+            tool.Ifc,
+            tool.Geometry,
+            obj=context.active_object,
+            representation=tool.Ifc.get().by_id(self.representation_id),
        )
-        ifcopenshell.api.run("geometry.remove_representation", self.file, **{"representation": representation})
-        Data.load(self.file, product.id())
-        return {"FINISHED"}


 class UpdateRepresentation(bpy.types.Operator):
@@ -173,6 +145,11 @@ class UpdateRepresentation(bpy.types.Operator):
        self.file = IfcStore.get_file()

        for obj in objs:
+            # TODO: write unit tests to see how this bulk operation handles
+            # contradictory ifc_representation_class values and when
+            # ifc_representation_class is IfcTextLiteral
+            if not obj.data:
+                continue
            self.update_obj_mesh_representation(context, obj)
            IfcStore.edited_objs.discard(obj)
        return {"FINISHED"}
@@ -180,11 +157,19 @@ class UpdateRepresentation(bpy.types.Operator):
    def update_obj_mesh_representation(self, context, obj):
        product = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)

+        if not product.is_a("IfcGridAxis"):
+            tool.Geometry.clear_cache(product)
+
        if product.is_a("IfcGridAxis"):
            ifcopenshell.api.run("grid.create_axis_curve", self.file, **{"axis_curve": obj, "grid_axis": product})
            return
+        if product.is_a("IfcRelSpaceBoundary"):
+            # TODO refactor
+            settings = tool.Boundary.get_assign_connection_geometry_settings(obj)
+            ifcopenshell.api.run("boundary.assign_connection_geometry", tool.Ifc.get(), **settings)
+            return

-        core.edit_object_placement(tool.Ifc, tool.Surveyor, obj=obj)
+        core.edit_object_placement(tool.Ifc, tool.Geometry, tool.Surveyor, obj=obj)

        old_representation = self.file.by_id(obj.data.BIMMeshProperties.ifc_definition_id)
        context_of_items = old_representation.ContextOfItems
@@ -206,8 +191,9 @@ class UpdateRepresentation(bpy.types.Operator):
            "geometry": obj.data,
            "coordinate_offset": coordinate_offset,
            "total_items": max(1, len(obj.material_slots)),
-            "should_force_faceted_brep": context.scene.BIMGeometryProperties.should_force_faceted_brep,
-            "should_force_triangulation": context.scene.BIMGeometryProperties.should_force_triangulation,
+            "should_force_faceted_brep": tool.Geometry.should_force_faceted_brep(),
+            "should_force_triangulation": tool.Geometry.should_force_triangulation(),
+            "should_generate_uvs": tool.Geometry.should_generate_uvs(obj),
            "ifc_representation_class": self.ifc_representation_class,
        }

@@ -216,6 +202,7 @@ class UpdateRepresentation(bpy.types.Operator):
                product, old_representation
            )
            representation_data["profile_set_usage"] = tool.Geometry.get_profile_set_usage(product)
+            representation_data["text_literal"] = tool.Geometry.get_text_literal(old_representation)

        new_representation = ifcopenshell.api.run("geometry.add_representation", self.file, **representation_data)

@@ -239,6 +226,7 @@ class UpdateRepresentation(bpy.types.Operator):
                    "should_use_presentation_style_assignment": context.scene.BIMGeometryProperties.should_use_presentation_style_assignment,
                },
            )
+            tool.Geometry.record_object_materials(obj)

        # TODO: move this into a replace_representation usecase or something
        for inverse in self.file.get_inverse(old_representation):
@@ -246,10 +234,10 @@ class UpdateRepresentation(bpy.types.Operator):

        obj.data.BIMMeshProperties.ifc_definition_id = int(new_representation.id())
        obj.data.name = f"{old_representation.ContextOfItems.id()}/{new_representation.id()}"
-        bpy.ops.bim.remove_representation(representation_id=old_representation.id(), obj=obj.name)
+        core.remove_representation(tool.Ifc, tool.Geometry, obj=obj, representation=old_representation)
        Data.load(self.file, obj.BIMObjectProperties.ifc_definition_id)
        if obj.data.BIMMeshProperties.ifc_parameters:
-            bpy.ops.bim.get_representation_ifc_parameters()
+            core.get_representation_ifc_parameters(tool.Geometry, obj=obj)


 class UpdateParametricRepresentation(bpy.types.Operator):
@@ -276,35 +264,20 @@ class UpdateParametricRepresentation(bpy.types.Operator):
            should_reload=True,
            enable_dynamic_voids=False,
            is_global=True,
+            should_sync_changes_first=False,
        )
        if show_representation_parameters:
-            bpy.ops.bim.get_representation_ifc_parameters()
+            core.get_representation_ifc_parameters(tool.Geometry, obj=obj)
        return {"FINISHED"}


-class GetRepresentationIfcParameters(bpy.types.Operator):
+class GetRepresentationIfcParameters(bpy.types.Operator, Operator):
    bl_idname = "bim.get_representation_ifc_parameters"
    bl_label = "Get Representation IFC Parameters"
    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        self.file = IfcStore.get_file()
-        obj = context.active_object
-        props = obj.data.BIMMeshProperties
-        elements = self.file.traverse(self.file.by_id(props.ifc_definition_id))
-        props.ifc_parameters.clear()
-        for element in elements:
-            if element.is_a("IfcRepresentationItem") or element.is_a("IfcParameterizedProfileDef"):
-                for i in range(0, len(element)):
-                    if element.attribute_type(i) == "DOUBLE":
-                        new = props.ifc_parameters.add()
-                        new.name = "{}/{}".format(element.is_a(), element.attribute_name(i))
-                        new.step_id = element.id()
-                        new.type = element.attribute_type(i)
-                        new.index = i
-                        if element[i]:
-                            new.value = element[i]
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.get_representation_ifc_parameters(tool.Geometry, obj=context.active_object)


 class CopyRepresentation(bpy.types.Operator, Operator):
@@ -357,9 +330,35 @@ class CopyRepresentation(bpy.types.Operator, Operator):
                    return r.MappedRepresentation


-class OverrideDelete(bpy.types.Operator):
+class OverrideDeleteTrait:
+    def delete_ifc_object(self, obj):
+        if obj.BIMObjectProperties.ifc_definition_id:
+            element = IfcStore.get_file().by_id(obj.BIMObjectProperties.ifc_definition_id)
+            IfcStore.delete_element(element)
+            if getattr(element, "FillsVoids", None):
+                self.remove_filling(element)
+            if element.is_a("IfcOpeningElement"):
+                for rel in element.HasFillings:
+                    self.remove_filling(rel.RelatedBuildingElement)
+                if element.VoidsElements:
+                    self.delete_opening_element(element)
+            elif getattr(element, "HasOpenings", None):
+                for rel in element.HasOpenings:
+                    self.delete_opening_element(rel.RelatedOpeningElement)
+
+    def delete_opening_element(self, element):
+        obj = IfcStore.get_element(element.VoidsElements[0].RelatingBuildingElement.id())
+        bpy.ops.bim.remove_opening(opening_id=element.id(), obj=obj.name)
+
+    def remove_filling(self, element):
+        obj = IfcStore.get_element(element.id())
+        bpy.ops.bim.remove_filling(obj=obj.name)
+
+
+class OverrideDelete(bpy.types.Operator, OverrideDeleteTrait):
    bl_idname = "object.delete"
    bl_label = "Delete"
+    bl_options = {"REGISTER", "UNDO"}
    use_global: bpy.props.BoolProperty(default=False)
    confirm: bpy.props.BoolProperty(default=True)

@@ -373,41 +372,99 @@ class OverrideDelete(bpy.types.Operator):
            return IfcStore.execute_ifc_operator(self, context)
        for obj in context.selected_objects:
            bpy.data.objects.remove(obj)
+        # Required otherwise gizmos are still visible
+        context.view_layer.objects.active = None
        return {"FINISHED"}

    def invoke(self, context, event):
-        return context.window_manager.invoke_confirm(self, event)
+        if self.confirm:
+            return context.window_manager.invoke_confirm(self, event)
+        self.confirm = True
+        return self.execute(context)

    def _execute(self, context):
-        file = IfcStore.get_file()
        for obj in context.selected_objects:
-            if obj.BIMObjectProperties.ifc_definition_id:
-                element = file.by_id(obj.BIMObjectProperties.ifc_definition_id)
-                if element.FillsVoids:
-                    self.remove_filling(element)
-                if element.is_a("IfcOpeningElement"):
-                    for rel in element.HasFillings:
-                        self.remove_filling(rel.RelatedBuildingElement)
-                    if element.VoidsElements:
-                        self.delete_opening_element(element)
-                elif element.HasOpenings:
-                    for rel in element.HasOpenings:
-                        self.delete_opening_element(rel.RelatedOpeningElement)
+            self.delete_ifc_object(obj)
            bpy.data.objects.remove(obj)
+        # Required otherwise gizmos are still visible
+        context.view_layer.objects.active = None
        return {"FINISHED"}

-    def delete_opening_element(self, element):
-        obj = IfcStore.get_element(element.VoidsElements[0].RelatingBuildingElement.id())
-        bpy.ops.bim.remove_opening(opening_id=element.id(), obj=obj.name)

-    def remove_filling(self, element):
-        obj = IfcStore.get_element(element.id())
-        bpy.ops.bim.remove_filling(obj=obj.name)
+class OverrideOutlinerDelete(bpy.types.Operator, OverrideDeleteTrait):
+    bl_idname = "outliner.delete"
+    bl_label = "Delete"
+    bl_options = {"REGISTER", "UNDO"}
+    hierarchy: bpy.props.BoolProperty(default=False)
+
+    @classmethod
+    def poll(cls, context):
+        return len(context.selected_ids) > 0
+
+    def execute(self, context):
+        # In this override, we don't check self.hierarchy. This effectively
+        # makes Delete and Delete Hierarchy identical. This is on purpose, since
+        # non-hierarchical deletion may imply a whole bunch of potentially
+        # unintended IFC spatial modifications. To make life less confusing for
+        # the user, Delete means Delete. End of story.
+        # Deep magick from the dawn of time
+        if IfcStore.get_file():
+            return IfcStore.execute_ifc_operator(self, context)
+        # https://blender.stackexchange.com/questions/203729/python-get-selected-objects-in-outliner
+        objects_to_delete = set()
+        collections_to_delete = set()
+        for item in context.selected_ids:
+            if item.bl_rna.identifier == "Collection":
+                collection = bpy.data.collections.get(item.name)
+                collection_data = self.get_collection_objects_and_children(collection)
+                objects_to_delete |= collection_data["objects"]
+                collections_to_delete |= collection_data["children"]
+                collections_to_delete.add(collection)
+            elif item.bl_rna.identifier == "Object":
+                objects_to_delete.add(bpy.data.objects.get(item.name))
+        for obj in objects_to_delete:
+            bpy.data.objects.remove(obj)
+        for collection in collections_to_delete:
+            bpy.data.collections.remove(collection)
+        return {"FINISHED"}
+
+    def _execute(self, context):
+        objects_to_delete = set()
+        collections_to_delete = set()
+        for item in context.selected_ids:
+            if item.bl_rna.identifier == "Collection":
+                collection = bpy.data.collections.get(item.name)
+                collection_data = self.get_collection_objects_and_children(collection)
+                objects_to_delete |= collection_data["objects"]
+                collections_to_delete |= collection_data["children"]
+                collections_to_delete.add(collection)
+            elif item.bl_rna.identifier == "Object":
+                objects_to_delete.add(bpy.data.objects.get(item.name))
+        for obj in objects_to_delete:
+            # This is the only difference
+            self.delete_ifc_object(obj)
+            bpy.data.objects.remove(obj)
+        for collection in collections_to_delete:
+            bpy.data.collections.remove(collection)
+        return {"FINISHED"}
+
+    def get_collection_objects_and_children(self, collection):
+        objects = set()
+        children = set()
+        queue = [collection]
+        while queue:
+            collection = queue.pop()
+            for obj in collection.objects:
+                objects.add(obj)
+            queue.extend(collection.children)
+            children = children.union(collection.children)
+        return {"objects": objects, "children": children}


 class OverrideDuplicateMove(bpy.types.Operator):
    bl_idname = "object.duplicate_move"
    bl_label = "Duplicate Objects"
+    bl_options = {"REGISTER", "UNDO"}

    @classmethod
    def poll(cls, context):
@@ -29,6 +29,7 @@ class BIM_PT_representations(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_geometry_object"

    @classmethod
    def poll(cls, context):
@@ -49,7 +50,7 @@ class BIM_PT_representations(Panel):
            layout.label(text="No representations found")

        row = layout.row(align=True)
-        row.prop(context.scene.BIMProperties, "contexts", text="")
+        row.prop(context.scene.BIMRootProperties, "contexts", text="")
        row.operator("bim.add_representation", icon="ADD", text="")

        for representation in RepresentationsData.data["representations"]:
@@ -30,6 +30,7 @@ class BIM_PT_gis(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_geometry"

    @classmethod
    def poll(cls, context):
@@ -0,0 +1,37 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+from . import prop
+from . import operator
+from . import ui
+
+classes = (
+    prop.BIMCityJsonProperties,
+    operator.BIM_OT_cityjson2ifc,
+    operator.BIM_OT_find_cityjson_lod,
+    ui.BIM_PT_cityjson_converter,
+)
+
+
+def register():
+    bpy.types.Scene.ifccityjson_properties = bpy.props.PointerProperty(type=prop.BIMCityJsonProperties)
+
+
+def unregister():
+    del bpy.types.Scene.ifccityjson_properties
@@ -0,0 +1,69 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+from bpy.types import Operator
+
+
+class BIM_OT_cityjson2ifc(Operator):
+    bl_idname = "bim.convert_cityjson2ifc"
+    bl_label = "Convert CityJSON to IFC"
+    bl_context = "scene"
+
+    def execute(self, context):
+        from cjio import cityjson
+        from ifccityjson.cityjson2ifc.cityjson2ifc import Cityjson2ifc
+
+        props = context.scene.ifccityjson_properties
+        city_model = cityjson.load(props.input, transform=False)
+        data = {
+            "file_destination": props.output,
+            "lod": props.lod,
+            "split": props.split_lod,
+        }
+        if props.name != "":
+            data["name_attribute"] = props.name
+
+        converter = Cityjson2ifc()
+        converter.configuration(**data)
+        converter.convert(city_model)
+        if props.load_after_convert:
+            bpy.ops.bim.load_project(filepath=props.output)
+        return {"FINISHED"}
+
+
+class BIM_OT_find_cityjson_lod(Operator):
+    bl_idname = "bim.find_cityjson_lod"
+    bl_label = "Find LODs in CityJSON file"
+    bl_context = "scene"
+
+    def execute(self, context):
+        from cjio import cityjson
+
+        props = context.scene.ifccityjson_properties
+        city_model = cityjson.load(props.input)
+        lods = set()
+        for obj_id, obj in city_model.get_cityobjects().items():
+            for geometry in obj.geometry:
+                lod = str(geometry.lod)
+                if lod not in lods:
+                    lods.add(lod)
+                    props.lods.add()
+                    props.lods[-1].name = lod
+        props.is_lod_found = True
+        return {"FINISHED"}
@@ -0,0 +1,36 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+from bpy.types import PropertyGroup
+from bpy.props import StringProperty, BoolProperty, EnumProperty, CollectionProperty
+from blenderbim.bim.prop import StrProperty
+
+
+class BIMCityJsonProperties(PropertyGroup):
+    def get_lods(self, context):
+        return [(item.name, "LOD" + item.name, "Level of Detail " + item.name) for item in self.lods]
+
+    # TODO: instead of subtype it would be nice to have a helper operator that allows filtered file browsing
+    input: StringProperty(name="CityJSON Input", default="", subtype="FILE_PATH")
+    output: StringProperty(name="IFC Output", default="", subtype="FILE_PATH")
+    name: StringProperty(name="Identifier", default="")
+    split_lod: BoolProperty(name="Should Split LOD", default=True)
+    lods: CollectionProperty(name="LODs", type=StrProperty)
+    lod: EnumProperty(name="LOD", description="", items=get_lods, options={"ANIMATABLE"}, default=None)
+    is_lod_found: BoolProperty(name="Is LOD Found", default=False)
+    load_after_convert: BoolProperty(name="Load After Converting", default=True)
@@ -0,0 +1,52 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+from bpy.types import Panel
+
+
+class BIM_PT_cityjson_converter(Panel):
+    bl_label = "IFC CityJSON"
+    bl_idname = "BIM_PT_ifccityjson"
+    bl_options = {"DEFAULT_CLOSED"}
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+    bl_context = "scene"
+    bl_parent_id = "BIM_PT_collaboration"
+
+    def draw(self, context):
+        layout = self.layout
+        scene = context.scene
+        props = scene.ifccityjson_properties
+
+        row = layout.row(align=True)
+        row.prop(props, "input")
+        row = layout.row(align=True)
+        row.operator("bim.find_cityjson_lod")
+        row = layout.row(align=True)
+        row.prop(props, "output")
+        row = layout.row(align=True)
+        row.prop(props, "name")
+        row = layout.row(align=True)
+        row.prop(props, "split_lod")
+        row.prop(props, "load_after_convert")
+        row = layout.row(align=True)
+        row.prop(props, "lod")
+        if not props.is_lod_found:
+            row.enabled = False
+        row = layout.row(align=True)
+        row.operator("bim.convert_cityjson2ifc")
@@ -28,6 +28,7 @@ class BIM_PT_groups(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_project_setup"

    @classmethod
    def poll(cls, context):
@@ -74,6 +75,7 @@ class BIM_PT_object_groups(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
+    bl_parent_id = "BIM_PT_utilities_object"

    @classmethod
    def poll(cls, context):
@@ -28,6 +28,7 @@ class BIM_PT_layers(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
+    bl_parent_id = "BIM_PT_geometry_object"

    @classmethod
    def poll(cls, context):
@@ -21,6 +21,7 @@ from . import ui, prop, operator

 classes = (
    operator.CalculateLCA,
+    operator.ConnectOpenLCA,
    prop.BIMLCAProperties,
    ui.BIM_PT_lca,
 )
--- a/Show More
+++ b/Show More