#1153 Implement adding and removing schedules from a sheet

#1153 Reimplement ability to build SVG tables from referenced ODS documents
[IfcConvert] Added IfcWorkPlan to xml export
2026-08-09 09:21:46 +00:00 · 2022-04-29 13:32:34 +10:00 · 2022-04-28 19:57:47 +10:00 · 2022-04-28 17:54:43 +10:00 · 2022-04-28 17:54:43 +10:00 · 2022-04-28 17:54:43 +10:00
333 changed files with 24392 additions and 7673 deletions
@@ -29,7 +29,7 @@ jobs:
    strategy:
      fail-fast: false
      matrix:
-        pyver: [py37, py39]
+        pyver: [py37, py39, py310]
        config:
          - {
            name: "Windows Build",
@@ -82,6 +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 libocct-foundation-dev libocct-modeling-algorithms-dev libocct-modeling-data-dev libocct-ocaf-dev libocct-visualization-dev libocct-data-exchange-dev \
-          libhdf5-dev
+          libhdf5-dev libcgal-dev
          
      - name: Build
        env:
@@ -5,6 +5,15 @@
 /_installed-vs*-x*/
 /build/

+# output directories
+/cmake/out/
+/docs/out/
+/src/examples/out/
+/src/ifcmax/out/
+/src/ifcwrap/out/
+/src/qtviewer/out/
+
+
 /win/BuildDepsCache*.txt
 # IfcExpressParser residue
 /src/ifcexpressparser/express_parser.py
@@ -13,6 +22,7 @@ __pycache__
 *.py.bak
 # Visual Studio Code files
 .vscode
+.vs
 # PyCharm files
 .idea

@@ -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
@@ -39,6 +39,8 @@ Note 1: The path where the source code is cloned to can contain spaces but non-A

 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
 in win/ folder. **See [win/readme.md] for more information**.
@@ -62,8 +62,12 @@ 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)

-# 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)
+IF(NOT CMAKE_BUILD_TYPE)
+	SET(CMAKE_BUILD_TYPE "Release")
+ENDIF()
+
+# QtViewer requires Qt5
+OPTION(BUILD_QTVIEWER "Build IfcOpenShell Qt GUI Viewer" OFF)
 include(GNUInstallDirs)
 if((BUILD_CONVERT OR BUILD_GEOMSERVER OR BUILD_IFCPYTHON) AND (NOT BUILD_IFCGEOM))
    message(STATUS "'IfcGeom' is required with current outputs")
@@ -444,13 +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()
    
@@ -470,10 +478,6 @@ if(HDF5_SUPPORT)
 	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,
@@ -881,6 +885,9 @@ INSTALL(FILES  ${SERIALIZERS_S_FILES}
 )
 endif()

+IF(BUILD_QTVIEWER)
+    ADD_SUBDIRECTORY(../src/qtviewer qtviewer)
+endif()

 list(APPEND CPACK_SOURCE_IGNORE_FILES
  .git
@@ -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
@@ -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-$(PYNUMBER)-v0.7.0-4c40fc1-$(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
@@ -488,6 +510,14 @@ endif
 	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
@@ -79,17 +79,18 @@ for name in modules.keys():


 classes = [
-    operator.OpenUri,
-    operator.SelectDataDir,
-    operator.SelectSchemaDir,
-    operator.SelectIfcFile,
-    operator.OpenUpstream,
+    operator.AddIfcFile,
    operator.BIM_OT_add_section_plane,
    operator.BIM_OT_remove_section_plane,
-    operator.ReloadIfcFile,
-    operator.AddIfcFile,
-    operator.RemoveIfcFile,
    operator.ConfigureVisibility,
+    operator.OpenUpstream,
+    operator.OpenUri,
+    operator.ReloadIfcFile,
+    operator.RemoveIfcFile,
+    operator.SelectDataDir,
+    operator.SelectIfcFile,
+    operator.SelectSchemaDir,
+    operator.SelectURIAttribute,
    prop.StrProperty,
    prop.ObjProperty,
    prop.Attribute,
@@ -105,17 +106,17 @@ classes = [
    ui.BIM_UL_generic,
    ui.BIM_UL_topics,
    ui.BIM_ADDON_preferences,
-    # scene panel groups -->
+    # Scene panel groups
+    ui.BIM_PT_project_info,
    ui.BIM_PT_project_setup,
-    ui.BIM_PT_utilities,
    ui.BIM_PT_collaboration,
    ui.BIM_PT_geometry,
-    ui.BIM_PT_4D5D,
-    ui.BIM_PT_structural,
    ui.BIM_PT_services,
-    ui.BIM_PT_misc,
+    ui.BIM_PT_structural,
+    ui.BIM_PT_4D5D,
    ui.BIM_PT_quality_control,
-    # object panel groups -->
+    ui.BIM_PT_integrations,
+    # Object panel groups
    ui.BIM_PT_object_metadata,
    ui.BIM_PT_geometry_object,
    ui.BIM_PT_services_object,
@@ -38,7 +38,7 @@
 <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
@@ -50,6 +50,8 @@ g.setOptions({
    vFormatArr: ['Day', 'Week', 'Month', 'Quarter'], // Even with setUseSingleCell using Hour format on such a large chart can cause issues in some browsers,
    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,
 });
@@ -0,0 +1,13 @@
+ISO-10303-21;
+HEADER;
+FILE_DESCRIPTION((),'2;1');
+FILE_NAME('EPset_Annotation.ifc','2020-01-01T00:00:00',(),(),'EPset_Annotation','EPset_Annotation',$);
+FILE_SCHEMA(('IFC4'));
+ENDSEC;
+DATA;
+#1=IFCPROPERTYSETTEMPLATE('3VuPUwdCD2Qx3XDDRs0R1N',$,'EPset_Annotation','',.PSET_OCCURRENCEDRIVEN.,'IfcAnnotation',(#2,#3));
+#2=IFCSIMPLEPROPERTYTEMPLATE('2P7JN79n96Q9pElZ83LKe4',$,'ZIndex','',.P_SINGLEVALUE.,'IfcInteger',$,$,$,$,$,.READWRITE.);
+#3=IFCSIMPLEPROPERTYTEMPLATE('1Wpx_r2xj1_9w5JpI0QRJy',$,'Symbol','',.P_ENUMERATEDVALUE.,'IfcLabel',$,#4,$,$,$,.READWRITE.);
+#4=IFCPROPERTYENUMERATION('Symbol',(IFCLABEL('rectangle-tag'), IFCLABEL('door-tag')),$);
+ENDSEC;
+END-ISO-10303-21;
@@ -0,0 +1,20 @@
+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,#8,#9,#10,#11));
+#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.);
+#8=IFCSIMPLEPROPERTYTEMPLATE('2NPPxuABv1huDTVh32TFgw',$,'GlobalReferencing','',.P_SINGLEVALUE.,'IfcBoolean',$,$,$,$,$,.READWRITE.);
+#9=IFCSIMPLEPROPERTYTEMPLATE('10hT_1zrzEbRRKMXYAWvtD',$,'Metadata','',.P_SINGLEVALUE.,'IfcText',$,$,$,$,$,.READWRITE.);
+#10=IFCSIMPLEPROPERTYTEMPLATE('3Z0BXPSG5CWgtI33ioV7aj',$,'Include','',.P_SINGLEVALUE.,'IfcText',$,$,$,$,$,.READWRITE.);
+#11=IFCSIMPLEPROPERTYTEMPLATE('1RVts_g3PAw98PJA2yL3bO',$,'Exclude','',.P_SINGLEVALUE.,'IfcText',$,$,$,$,$,.READWRITE.);
+ENDSEC;
+END-ISO-10303-21;
@@ -23,12 +23,26 @@ 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); }
-.break { fill: white; }
-.breakline { fill: none; stroke: black; stroke-linecap: 'round'; stroke-width: 0.25; marker-mid: url(#breakline-marker); }
+.IfcAnnotation { fill: none; stroke: black; stroke-linecap: 'round'; stroke-width: 0.25; }
+.PredefinedType-LINEWORK { 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-SECTION { stroke-dasharray: 12.5, 3, 3, 3; }
+.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-RADIUS { marker-end: url(#radius-marker-end); }
+.PredefinedType-DIAMETER { marker-start: url(#diameter-marker-start); marker-end: url(#diameter-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-FILLAREA { fill: white; stroke: none; }
+.PredefinedType-BREAKLINE { fill: none; stroke: black; stroke-width: 0.25; marker-mid: url(#breakline-marker); }
+.PredefinedType-TEXT { fill: black; stroke: none; }
+path.PredefinedType-TEXTLEADER { marker-end: url(#leader-marker); }
+text.PredefinedType-TEXTLEADER { fill: black; stroke: none; }
 .material-blank { fill: white; }
 .material-diagonal1 { fill: url(#diagonal1); }
 .material-diagonal2 { fill: url(#diagonal2); }
@@ -44,5 +58,9 @@ 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" ?>
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+    <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" />
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    <marker id="eng-dimension-marker-start" markerHeight="14" markerWidth="11" orient="auto" refX="1" refY="7">
        <g>
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@@ -12,6 +16,23 @@
            <path d="M 10 0 L 10 14" class="annotation" style="stroke-width:1;" />
        </g>
    </marker>
+    <marker id="radius-marker-end" markerHeight="14" markerWidth="11" orient="auto" refX="10" refY="7">
+        <g>
+            <path d="M 0 3.5 L 0 10.5 L 10 7" class="annotation" style="fill:black;" />
+        </g>
+    </marker>
+    <marker id="diameter-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;" />
+            <path d="M 1 0 L 1 14" class="annotation" style="stroke-width:1;" />
+        </g>
+    </marker>
+    <marker id="diameter-marker-end" markerHeight="14" markerWidth="11" orient="auto" refX="10" refY="7">
+        <g>
+            <path d="M 0 3.5 L 0 10.5 L 10 7" class="annotation" style="fill:black;" />
+            <path d="M 10 0 L 10 14" class="annotation" style="stroke-width:1;" />
+        </g>
+    </marker>
    <marker id="dimension-marker-start" markerHeight="30" markerWidth="20" refX="10" refY="15" orient="auto">
        <g>
            <path d="M 0 15 L 20 15" class="annotation" style="stroke-width:1;" />
@@ -53,7 +74,7 @@
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        </g>
    </marker>
-    <marker id="breakline-marker" markerHeight="20" markerWidth="15" refX="7.5" refY="10">
+    <marker id="breakline-marker" markerHeight="20" markerWidth="15" refX="7.5" refY="10" orient="auto">
        <g>
            <path d="M 0 10 L 5 20 L 7.5 10" class="annotation" style="stroke-width:1; fill: white;" />
            <path d="M 7.5 10 L 10 0 L 15 10" class="annotation" style="stroke-width:1; fill: white;" />
@@ -3,6 +3,10 @@
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    <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" />
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@@ -80,6 +84,9 @@
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    <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">
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 <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 @@
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         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 @@
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         y="105.0553"
         x="39.285267"
-         id="tspan865">{{scale}}</tspan></text>
+         id="tspan865">{{Scale}}</tspan></text>
  </g>
 </svg>
@@ -28,6 +28,7 @@ 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
@@ -47,7 +48,7 @@ class IfcExporter:
            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))
@@ -179,6 +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)
+        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
@@ -48,6 +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):
@@ -78,6 +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":
@@ -43,6 +43,7 @@ class IfcStore:
    library_file = None
    element_listeners = set()
    undo_redo_stack_objects = set()
+    undo_redo_stack_object_names = {}
    current_transaction = ""
    last_transaction = ""
    history = []
@@ -86,6 +87,7 @@ class IfcStore:
            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:
@@ -146,14 +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.
@@ -168,14 +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:
@@ -186,6 +215,38 @@ 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())
@@ -311,6 +372,7 @@ class IfcStore:
    @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
@@ -32,6 +34,7 @@ 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

@@ -160,6 +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()
@@ -279,6 +283,14 @@ 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
@@ -345,16 +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

@@ -378,6 +391,8 @@ class IfcImporter:
        props = bpy.context.scene.BIMGeoreferenceProperties
        if props.has_blender_offset:
            return
+        if self.ifc_import_settings.should_offset_model:
+            return self.set_manual_blender_offset()
        if self.file.schema == "IFC2X3":
            project = self.file.by_type("IfcProject")[0]
        else:
@@ -390,6 +405,13 @@ class IfcImporter:
            return self.guess_georeferencing(building)
        return self.guess_absolute_coordinate()

+    def set_manual_blender_offset(self):
+        props = bpy.context.scene.BIMGeoreferenceProperties
+        props.blender_eastings = str(self.ifc_import_settings.model_offset_coordinates[0])
+        props.blender_northings = str(self.ifc_import_settings.model_offset_coordinates[1])
+        props.blender_orthogonal_height = str(self.ifc_import_settings.model_offset_coordinates[2])
+        props.has_blender_offset = True
+
    def guess_georeferencing(self, element):
        if not element.ObjectPlacement or not element.ObjectPlacement.is_a("IfcLocalPlacement"):
            return
@@ -406,10 +428,12 @@ class IfcImporter:
        props.has_blender_offset = True

    def guess_absolute_coordinate(self):
-        # Civil BIM applications like to work in absolute coordinates, where the ObjectPlacement is 0,0,0 but each
-        # individual coordinate of the shape representation is in absolute values.
+        # Civil BIM applications like to work in absolute coordinates, where the
+        # ObjectPlacement is usually 0,0,0 (but not always, so we'll need to
+        # check for the actual transformation) but each individual coordinate of
+        # the shape representation is in absolute values.
        offset_point = self.get_offset_point()
-        if not offset_point:
+        if offset_point is None:
            return
        props = bpy.context.scene.BIMGeoreferenceProperties
        props.blender_eastings = str(offset_point[0])
@@ -419,39 +443,48 @@ class IfcImporter:

    def get_offset_point(self):
        elements_checked = 0
-        # If more than these points aren't far away, the file probably isn't absolutely positioned
-        element_checking_threshold = 100
-        if self.file.schema == "IFC2X3":
-            # IFC2X3 does not have IfcCartesianPointList3D
-            point_lists = []
-        else:
-            point_lists = self.file.by_type("IfcCartesianPointList3D")
-        for point_list in point_lists:
-            elements_checked += 1
-            if elements_checked > element_checking_threshold:
-                return
-            for i, point in enumerate(point_list.CoordList):
-                if len(point) == 3 and self.is_point_far_away(point, is_meters=False):
-                    return point
-
-        for point in self.file.by_type("IfcCartesianPoint"):
-            is_used_in_placement = False
-            for inverse in self.file.get_inverse(point):
-                if inverse.is_a("IfcAxis2Placement3D"):
-                    is_used_in_placement = True
-                    break
-            if is_used_in_placement:
+        # If more than these elements aren't far away, the file probably isn't absolutely positioned
+        element_checking_threshold = 10
+        for element in self.file.by_type("IfcElement"):
+            if not element.Representation:
                continue
            elements_checked += 1
            if elements_checked > element_checking_threshold:
                return
-            if len(point.Coordinates) == 3 and self.is_point_far_away(point, is_meters=False):
-                return point.Coordinates
+            if not self.does_element_likely_have_geometry_far_away(element):
+                continue
+            shape = ifcopenshell.geom.create_shape(self.settings, element)
+            m = shape.transformation.matrix.data
+            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])
+            )
+            point = np.array(
+                (
+                    shape.geometry.verts[0] / self.unit_scale,
+                    shape.geometry.verts[1] / self.unit_scale,
+                    shape.geometry.verts[2] / self.unit_scale,
+                    0.0,
+                )
+            )
+            return mat @ point
+
+    def does_element_likely_have_geometry_far_away(self, element):
+        for representation in element.Representation.Representations:
+            for subelement in self.file.traverse(representation):
+                if subelement.is_a("IfcCartesianPointList3D"):
+                    for point in subelement.CoordList:
+                        if len(point) == 3 and self.is_point_far_away(point, is_meters=False):
+                            return True
+                if subelement.is_a("IfcCartesianPoint"):
+                    if len(subelement.Coordinates) == 3 and self.is_point_far_away(subelement, is_meters=False):
+                        return True

    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,
@@ -461,13 +494,6 @@ 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]
-            matrix[1, 3] += self.ifc_import_settings.model_offset_coordinates[1]
-            matrix[2, 3] += self.ifc_import_settings.model_offset_coordinates[2]

        return mathutils.Matrix(matrix.tolist())

@@ -561,7 +587,6 @@ 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:
@@ -583,14 +608,6 @@ 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):
@@ -852,78 +869,138 @@ 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 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"]]
+        for representation in element.Representation.Representations:
+            if representation.ContextOfItems.id() not in self.body_contexts:
+                continue
+            self.convert_representation(representation)

-                    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")
-
-        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 = 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"] = materials
-        mesh["ios_material_ids"] = material_ids
+        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")
@@ -1234,25 +1311,172 @@ 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)
@@ -1298,9 +1522,10 @@ 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 self.is_drawing_annotation(element):
-            group = [r for r in element.HasAssignments if r.is_a("IfcRelAssignsToGroup")][0].RelatingGroup
-            return self.collections[group.GlobalId].objects.link(obj)
+        elif element.is_a("IfcAnnotation"):
+            group = self.get_drawing_group(element)
+            if group:
+                return self.collections[group.GlobalId].objects.link(obj)

        container = ifcopenshell.util.element.get_container(element)
        if container:
@@ -1320,28 +1545,16 @@ class IfcImporter:
        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",
-        ]
+    def get_drawing_group(self, element):
+        for rel in element.HasAssignments or []:
+            if rel.is_a("IfcRelAssignsToGroup"):
+                return rel.RelatingGroup

    def get_element_matrix(self, element):
        result = ifcopenshell.util.placement.get_local_placement(element.ObjectPlacement)
@@ -1467,6 +1680,12 @@ 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):
@@ -1509,20 +1728,34 @@ 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,
+                m = shape.transformation.matrix.data
+                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])
                )
-                for i, vert in enumerate(geometry.verts):
-                    if ordinate_index > 2:
-                        ordinate_index = 0
-                    verts[i] = vert - offset_point[ordinate_index]
-                    ordinate_index += 1
+                offset_point = np.linalg.inv(mat) @ np.array(
+                    (
+                        float(props.blender_eastings),
+                        float(props.blender_northings),
+                        float(props.blender_orthogonal_height),
+                        0.0,
+                    )
+                )
+                verts = [None] * len(geometry.verts)
+                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],
+                        offset_point[0] * self.unit_scale,
+                        offset_point[1] * self.unit_scale,
+                        offset_point[2] * 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
@@ -1610,7 +1843,8 @@ 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
@@ -1637,11 +1871,13 @@ 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()
@@ -33,7 +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"}
@@ -50,7 +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"}
@@ -66,7 +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"}
@@ -75,7 +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"}
@@ -84,7 +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"}
@@ -99,12 +109,7 @@ class AddAggregate(bpy.types.Operator):
        if not element:
            return {"FINISHED"}

-        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")
-
+        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)
@@ -126,3 +131,73 @@ class AddAggregate(bpy.types.Operator):
            )
        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")
+        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)
@@ -44,13 +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="")
@@ -58,15 +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
@@ -60,7 +60,6 @@ class BIM_PT_object_attributes(Panel):
    bl_region_type = "WINDOW"
    bl_context = "object"
    bl_parent_id = "BIM_PT_object_metadata"
-    bl_options = {"DEFAULT_CLOSED"}

    @classmethod
    def poll(cls, context):
@@ -82,8 +81,6 @@ class BIM_PT_material_attributes(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "material"
-    bl_parent_id = "BIM_PT_object_metadata"
-    bl_options = {"DEFAULT_CLOSED"}

    @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
@@ -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")
@@ -26,7 +26,7 @@ import blenderbim.bim.import_ifc as import_ifc


 def get_boundaries_collection(blender_space):
-    space_collection = bpy.data.collections.get(blender_space.name)
+    space_collection = bpy.data.collections.get(blender_space.name, blender_space.users_collection[0])
    collection_name = f"Boundaries/{blender_space.BIMObjectProperties.ifc_definition_id}"
    boundaries_collection = space_collection.children.get(collection_name)
    if not boundaries_collection:
@@ -44,6 +44,19 @@ class Loader:
        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)
@@ -61,13 +74,7 @@ class Loader:
        obj = tool.Ifc.get_object(boundary)
        if obj:
            return obj
-        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)
+        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)
@@ -29,7 +29,7 @@ class BIM_PT_constraints(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
-    bl_parent_id = "BIM_PT_misc"
+    bl_parent_id = "BIM_PT_project_setup"

    @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
@@ -32,6 +32,7 @@

 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 (
@@ -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):
@@ -29,46 +29,50 @@ class BIM_PT_documents(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
-    bl_parent_id = "BIM_PT_collaboration"
+    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):
@@ -89,88 +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)
@@ -33,9 +33,14 @@ classes = (
    operator.AddSheet,
    operator.BuildSchedule,
    operator.CleanWireframes,
+    operator.ContractSheet,
+    operator.ConvertEdgeToArc,
    operator.CopyGrid,
    operator.CreateDrawing,
    operator.CreateSheets,
+    operator.DisableEditingDrawings,
+    operator.DisableEditingSchedules,
+    operator.DisableEditingSheets,
    operator.DisableEditingText,
    operator.DisableEditingTextProduct,
    operator.EditText,
@@ -43,12 +48,15 @@ classes = (
    operator.EditVectorStyle,
    operator.EnableEditingText,
    operator.EnableEditingTextProduct,
-    operator.GenerateReferences,
+    operator.ExpandSheet,
+    operator.LoadDrawings,
+    operator.LoadSchedules,
+    operator.LoadSheets,
+    operator.OpenSchedule,
    operator.OpenSheet,
    operator.OpenView,
-    operator.OpenViewCamera,
-    operator.RefreshDrawingList,
    operator.RemoveDrawing,
+    operator.RemoveDrawingFromSheet,
    operator.RemoveDrawingStyle,
    operator.RemoveDrawingStyleAttribute,
    operator.RemoveSchedule,
@@ -56,7 +64,6 @@ classes = (
    operator.ResizeText,
    operator.SaveDrawingStyle,
    operator.SelectDocIfcFile,
-    operator.SelectScheduleFile,
    prop.Variable,
    prop.Drawing,
    prop.Schedule,
@@ -67,12 +74,13 @@ 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,
@@ -35,13 +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
@@ -50,12 +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
@@ -83,9 +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):
@@ -102,8 +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
@@ -151,13 +151,13 @@ class Annotator:
        return obj

    @staticmethod
-    def get_annotation_obj(object_type, data_type, context):
-        collection = context.scene.camera.users_collection[0]
+    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":
+        elif object_type in ("TEXT_LEADER", "SECTION_LEVEL"):
            data = bpy.data.curves.new(object_type, type="CURVE")
            data.dimensions = "3D"
            data.resolution_u = 2
@@ -179,11 +179,15 @@ class Annotator:
        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))
@@ -23,6 +23,9 @@ import blenderbim.tool as tool

 def refresh():
    TextData.is_loaded = False
+    SheetsData.is_loaded = False
+    SchedulesData.is_loaded = False
+    DrawingsData.is_loaded = False


 class TextData:
@@ -54,3 +57,55 @@ class TextData:
        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"]]
+
+
+class SchedulesData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {"total_schedules": cls.total_schedules()}
+        cls.is_loaded = True
+
+    @classmethod
+    def total_schedules(cls):
+        return len([d for d in tool.Ifc.get().by_type("IfcDocumentInformation") if d.Scope == "SCHEDULE"])
@@ -40,7 +40,7 @@ class BaseDecorator:

    DEF_GLSL = """
        #define PI 3.141592653589793
-        #define MAX_POINTS 32
+        #define MAX_POINTS 64
        #define CIRCLE_SEGS 12
    """

@@ -170,12 +170,32 @@ class BaseDecorator:
        returns: iterable of blender objects
        """
        results = []
+        decoration_presets = (
+            "DIMENSION",
+            "TEXT_LEADER",
+            "STAIR_ARROW",
+            "HIDDEN_LINE",
+            "PLAN_LEVEL",
+            "SECTION_LEVEL",
+            "BREAKLINE",
+            "GRID",
+            "ELEVATION",
+            "SECTION",
+            "TEXT",
+        )
        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)
+            if element.is_a("IfcAnnotation"):
+                if element.ObjectType == self.objecttype:
+                    results.append(obj)
+                elif (
+                    self.objecttype == "MISC"
+                    and element.ObjectType not in decoration_presets
+                    and isinstance(obj.data, bpy.types.Mesh)
+                ):
+                    results.append(obj)
        return results

    def get_path_geom(self, obj, topo=True):
@@ -247,7 +267,7 @@ class BaseDecorator:
        """perform actual drawing stuff"""
        raise NotImplementedError()

-    def draw_lines(self, context, obj, vertices, indices, topology=None):
+    def draw_lines(self, context, obj, vertices, indices, topology=None, is_scale_dependant=True):
        region = context.region
        region3d = context.region_data
        color = context.scene.DocProperties.decorations_colour
@@ -277,14 +297,15 @@ 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)
+        if is_scale_dependant:
+            # 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)

@@ -357,11 +378,11 @@ class BaseDecorator:
            elif "/" in precision:
                precision = int(precision.split("/")[1])
        elif unit_system == "METRIC":
-            precision = 3
+            precision = 4
        else:
            return

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


 class DimensionDecorator(BaseDecorator):
@@ -459,27 +480,8 @@ class DimensionDecorator(BaseDecorator):
            self.draw_label(context, text, p0 + (dir) * 0.5, dir)


-class EqualityDecorator(DimensionDecorator):
-    """Decorator for equality objects
-    - outlines each segment
-    - augments with arrows on both sides
-    - puts 'EQ' label
-    """
-
-    objecttype = "EQUAL_DIMENSION"
-
-    def draw_labels(self, context, obj, vertices, indices):
-        region = context.region
-        region3d = context.region_data
-        for i0, i1 in indices:
-            v0 = Vector(vertices[i0])
-            v1 = Vector(vertices[i1])
-            p0 = location_3d_to_region_2d(region, region3d, v0)
-            p1 = location_3d_to_region_2d(region, region3d, v1)
-            dir = p1 - p0
-            if dir.length < 1:
-                continue
-            self.draw_label(context, "EQ", p0 + (dir) * 0.5, dir)
+class DiameterDecorator(DimensionDecorator):
+    objecttype = "DIAMETER"


 class LeaderDecorator(BaseDecorator):
@@ -568,6 +570,98 @@ class LeaderDecorator(BaseDecorator):
        self.draw_label(context, obj.BIMTextProperties.value, pos, dir, gap=0, center=False, vcenter=False)


+class RadiusDecorator(BaseDecorator):
+    """Decorating text with arrows
+    - head point with arrow
+    """
+
+    objecttype = "RADIUS"
+
+    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;
+    in uint type[];
+
+    void main() {
+        vec4 clip2win = matCLIP2WIN();
+        vec4 win2clip = matWIN2CLIP();
+
+        vec4 p0 = gl_in[0].gl_Position, p1 = gl_in[1].gl_Position;
+        uint t0 = type[0], t1 = type[1];
+
+        vec4 p0w = CLIP2WIN(p0), p1w = CLIP2WIN(p1);
+        vec4 edge = p1w - p0w, dir = normalize(edge);
+        vec4 gap1 = vec4(0);
+
+        vec4 p;
+
+        // end edge arrow for last segment
+        if (t1 == 2u) {
+            vec4 head[3];
+            arrow_head(dir, viewportDrawingScale * ARROW_SIZE, ARROW_ANGLE, head);
+
+            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();
+
+            gap1 = dir * viewportDrawingScale * ARROW_SIZE;
+        }
+
+        // stem, adjusted for and arrow
+        gl_Position = p0;
+        EmitVertex();
+        p = p1w - gap1;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+    }
+    """
+
+    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))
+
+        spline = obj.data.splines[0]
+        spline_points = spline.bezier_points if spline.bezier_points else spline.points
+        if spline_points:
+            length = (spline_points[-1].co - spline_points[-2].co).length
+            text = self.format_value(context, length)
+            self.draw_label(context, text, pos, dir, gap=0, center=False, vcenter=False)
+
+
 class StairDecorator(BaseDecorator):
    """Decorating stairs
    - head point with arrow
@@ -671,6 +765,7 @@ class HiddenDecorator(BaseDecorator):

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

    layout(lines) in;
    layout(line_strip, max_vertices=MAX_POINTS) out;
@@ -725,10 +820,61 @@ class HiddenDecorator(BaseDecorator):
        self.draw_lines(context, obj, verts, idxs)


-class MiscDecorator(HiddenDecorator):
+class MiscDecorator(BaseDecorator):
    objecttype = "MISC"

-    FRAG_GLSL = BaseDecorator.FRAG_GLSL
+    GEOM_GLSL = """
+    uniform vec2 winsize;
+    uniform float viewportDrawingScale;
+
+    layout(lines) in;
+    layout(line_strip, max_vertices=MAX_POINTS) out;
+
+    out float dist; // distance from starging point along segment
+
+    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 gap = dir * 1;
+
+        vec4 p;
+
+        // NB: something should be used to affect position, otherwise compiler eliminates winsize
+
+        dist = 0;
+        p = p0w + gap;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        dist = length(edge);
+        p = p1w - gap;
+        gl_Position = WIN2CLIP(p);
+        EmitVertex();
+        EndPrimitive();
+    }
+    """
+
+    FRAG_GLSL = """
+    uniform vec4 color;
+    in vec2 gl_FragCoord;
+    in float dist;
+    out vec4 fragColor;
+
+    void main() {
+        fragColor = color;
+    }
+    """
+
+    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)
+        self.draw_lines(context, obj, verts, idxs, is_scale_dependant=False)


 class LevelDecorator(BaseDecorator):
@@ -923,7 +1069,7 @@ class SectionLevelDecorator(LevelDecorator):


 class BreakDecorator(BaseDecorator):
-    """Decorator for dimension objects
+    """Decorator for breakline objects
    - first edge of a mesh with zigzag thingy in the middle

    Uses first two vertices in verts list.
@@ -990,21 +1136,10 @@ class BreakDecorator(BaseDecorator):

    def decorate(self, context, obj):
        if obj.data.is_editmode:
-            verts = self.get_editmesh_geom(obj)
+            verts, idxs = self.get_editmesh_geom(obj)
        else:
-            verts = self.get_mesh_geom(obj)
-        self.draw_lines(context, obj, verts, [(0, 1)])
-
-    def get_mesh_geom(self, obj):
-        # first vertices only
-        vertices = [obj.matrix_world @ obj.data.vertices[i].co for i in (0, 1)]
-        return vertices
-
-    def get_editmesh_geom(self, obj):
-        # first vertices only
-        mesh = bmesh.from_edit_mesh(obj.data)
-        vertices = [obj.matrix_world @ v.co for v in mesh.edges[0].verts]
-        return vertices
+            verts, idxs = self.get_mesh_geom(obj)
+        self.draw_lines(context, obj, verts, idxs)


 class GridDecorator(BaseDecorator):
@@ -1125,15 +1260,15 @@ class GridDecorator(BaseDecorator):
        self.draw_label(context, text, p1, dir, vcenter=True, gap=0)


-class SectionViewDecorator(LevelDecorator):
-    objecttype = "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
    """
    )

@@ -1144,12 +1279,14 @@ class SectionViewDecorator(LevelDecorator):
    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() {
@@ -1160,75 +1297,205 @@ class SectionViewDecorator(LevelDecorator):

        vec4 p0w = CLIP2WIN(p0), p1w = CLIP2WIN(p1);
        vec4 edge = p1w - p0w, dir = normalize(edge);
-        vec4 gap = dir * viewportDrawingScale * 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(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, viewportDrawingScale * TRIANGLE_L, viewportDrawingScale * 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, viewportDrawingScale * TRIANGLE_L, viewportDrawingScale * 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):
@@ -1318,16 +1585,18 @@ class TextDecorator(BaseDecorator):
 class DecorationsHandler:
    decorators_classes = [
        DimensionDecorator,
-        EqualityDecorator,
        GridDecorator,
        HiddenDecorator,
        LeaderDecorator,
+        RadiusDecorator,
+        DiameterDecorator,
        MiscDecorator,
        PlanLevelDecorator,
        SectionLevelDecorator,
        StairDecorator,
        BreakDecorator,
-        SectionViewDecorator,
+        SectionDecorator,
+        ElevationDecorator,
        TextDecorator,
    ]

@@ -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 drawing.camera.users_collection[0], 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):
@@ -53,7 +53,7 @@ def open_with_user_command(user_command, path):
    if user_command:
        commands = eval(user_command)
        for command in commands:
-            subprocess.run(command)
+            subprocess.Popen(command)
    else:
        webbrowser.open("file://" + path)

@@ -65,67 +65,28 @@ class Operator:
        return {"FINISHED"}


-class AddDrawing(bpy.types.Operator):
+class AddDrawing(bpy.types.Operator, Operator):
    bl_idname = "bim.add_drawing"
    bl_label = "Add Drawing"
    bl_options = {"REGISTER", "UNDO"}

-    @classmethod
-    def poll(cls, context):
-        return IfcStore.get_file()
-
-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        self.file = IfcStore.get_file()
-        new = context.scene.DocProperties.drawings.add()
-        new.name = "DRAWING {}".format(len(context.scene.DocProperties.drawings))
-        if not bpy.data.collections.get("Views"):
-            context.scene.collection.children.link(bpy.data.collections.new("Views"))
-        views_collection = bpy.data.collections.get("Views")
-        view_collection = bpy.data.collections.new("IfcGroup/" + new.name)
-        views_collection.children.link(view_collection)
-        camera = bpy.data.objects.new(new.name, bpy.data.cameras.new(new.name))
-        camera.location = (0, 0, 1.5)  # The view shall be 1.5m above the origin
-        camera.data.type = "ORTHO"
-        camera.data.ortho_scale = 50  # The default of 6m is too small
-        camera.data.clip_end = 10  # A slightly more reasonable default
-        if context.scene.unit_settings.system == "IMPERIAL":
-            camera.data.BIMCameraProperties.diagram_scale = '1/8"=1\'-0"|1/96'
-        else:
-            camera.data.BIMCameraProperties.diagram_scale = "1:100|1/100"
-        context.scene.camera = camera
-        view_collection.objects.link(camera)
-        area = next(area for area in context.screen.areas if area.type == "VIEW_3D")
-        area.spaces[0].region_3d.view_perspective = "CAMERA"
-        new.camera = camera
-        bpy.ops.bim.assign_class(obj=camera.name, ifc_class="IfcAnnotation", predefined_type="DRAWING")
-        bpy.ops.bim.activate_drawing_style()
-
-        bpy.ops.bim.add_group()
-        group = self.file.by_id(sorted(GroupData.groups.keys())[-1])
-        ifcopenshell.api.run("group.edit_group", self.file, **{"group": group, "attributes": {"Name": new.name}})
-        bpy.ops.bim.assign_group(product=camera.name, group=group.id())
-        pset = ifcopenshell.api.run(
-            "pset.add_pset",
-            self.file,
-            **{
-                "product": self.file.by_id(camera.BIMObjectProperties.ifc_definition_id),
-                "name": "EPset_Drawing",
-            },
+        self.props = context.scene.DocProperties
+        hint = self.props.location_hint
+        if self.props.target_view in ["PLAN_VIEW", "REFLECTED_PLAN_VIEW"]:
+            hint = int(hint)
+        core.add_drawing(
+            tool.Ifc,
+            tool.Collector,
+            tool.Drawing,
+            target_view=self.props.target_view,
+            location_hint=hint,
        )
-        ifcopenshell.api.run(
-            "pset.edit_pset",
-            self.file,
-            **{
-                "pset": pset,
-                "properties": {"TargetView": "PLAN_VIEW", "Scale": "1/100"},
-                "pset_template": blenderbim.bim.schema.ifc.psetqto.get_by_name("EPset_Drawing"),
-            },
-        )
-        PsetData.load(IfcStore.get_file(), camera.BIMObjectProperties.ifc_definition_id)
-        return {"FINISHED"}
+        try:
+            drawing = tool.Ifc.get().by_id(self.props.active_drawing_id)
+            core.sync_references(tool.Ifc, tool.Collector, tool.Drawing, drawing=drawing)
+        except:
+            pass


 class CreateDrawing(bpy.types.Operator):
@@ -144,6 +105,7 @@ class CreateDrawing(bpy.types.Operator):
        camera = context.scene.camera
        return (
            IfcStore.get_file()
+            and camera
            and camera.type == "CAMERA"
            and camera.data.type == "ORTHO"
            and camera.BIMObjectProperties.ifc_definition_id
@@ -157,9 +119,10 @@ class CreateDrawing(bpy.types.Operator):
        start = time.time()
        self.profile_code("Start drawing generation process")
        self.props = context.scene.DocProperties
+        self.cprops = self.camera.data.BIMCameraProperties
        self.drawing_name = self.file.by_id(self.camera.BIMObjectProperties.ifc_definition_id).Name
        self.get_scale()
-        if self.camera.data.BIMCameraProperties.update_representation(self.camera):
+        if self.cprops.update_representation(self.camera):
            bpy.ops.bim.update_representation(obj=self.camera.name, ifc_representation_class="")
        underlay_svg = self.generate_underlay(context)
        self.profile_code("Generate underlay")
@@ -224,13 +187,11 @@ class CreateDrawing(bpy.types.Operator):
        return svg_path

    def generate_underlay(self, context):
-        if not self.props.has_underlay:
+        if not self.cprops.has_underlay:
            return
        svg_path = os.path.join(context.scene.BIMProperties.data_dir, "cache", self.drawing_name + "-underlay.svg")
        context.scene.render.filepath = svg_path[0:-4] + ".png"
-        drawing_style = context.scene.DocProperties.drawing_styles[
-            self.camera.data.BIMCameraProperties.active_drawing_style_index
-        ]
+        drawing_style = context.scene.DocProperties.drawing_styles[self.cprops.active_drawing_style_index]

        if drawing_style.render_type == "DEFAULT":
            bpy.ops.render.render(write_still=True)
@@ -284,7 +245,7 @@ class CreateDrawing(bpy.types.Operator):
        return svg_path

    def generate_linework(self, context):
-        if not self.props.has_linework:
+        if not self.cprops.has_linework:
            return
        svg_path = os.path.join(context.scene.BIMProperties.data_dir, "cache", self.drawing_name + "-linework.svg")
        if os.path.isfile(svg_path) and self.props.should_use_linework_cache:
@@ -328,9 +289,10 @@ class CreateDrawing(bpy.types.Operator):
            # A drawing prioritises a target view context first, followed by a body context as a fallback
            body_contexts = []
            target_view_contexts = []
+            target_view = ifcopenshell.util.element.get_psets(self.camera_element)["EPset_Drawing"]["TargetView"]
            for rep_context in ifc.by_type("IfcGeometricRepresentationContext"):
                if rep_context.is_a("IfcGeometricRepresentationSubContext"):
-                    if rep_context.TargetView == context.scene.camera.data.BIMCameraProperties.target_view:
+                    if rep_context.TargetView == target_view:
                        target_view_contexts.append(rep_context.id())
                        continue
                if rep_context.ContextIdentifier in ["Body", "Facetation"]:
@@ -340,15 +302,16 @@ class CreateDrawing(bpy.types.Operator):
                    body_contexts.append(rep_context.id())
                    continue

-            elements = set(ifc.by_type("IfcElement")) - set(ifc.by_type("IfcOpeningElement"))
+            elements = tool.Drawing.get_drawing_elements(self.camera_element)

            self.setup_serialiser(ifc)
-            cache_settings = ifcopenshell.geom.settings(DISABLE_TRIANGULATION=True)
            cache = IfcStore.get_cache()
            [cache.remove(guid) for guid in invalidated_guids]

            if target_view_contexts and elements:
-                geom_settings = ifcopenshell.geom.settings(DISABLE_TRIANGULATION=True, INCLUDE_CURVES=True)
+                geom_settings = ifcopenshell.geom.settings(
+                    DISABLE_TRIANGULATION=True, STRICT_TOLERANCE=True, INCLUDE_CURVES=True
+                )
                geom_settings.set_context_ids(target_view_contexts)
                it = ifcopenshell.geom.iterator(geom_settings, ifc, multiprocessing.cpu_count(), include=elements)
                it.set_cache(cache)
@@ -359,18 +322,14 @@ class CreateDrawing(bpy.types.Operator):
                elements -= processed

            if body_contexts and elements:
-                geom_settings = ifcopenshell.geom.settings(
-                    DISABLE_TRIANGULATION=True,
-                )
+                geom_settings = ifcopenshell.geom.settings(DISABLE_TRIANGULATION=True, STRICT_TOLERANCE=True)
                geom_settings.set_context_ids(body_contexts)
                it = ifcopenshell.geom.iterator(geom_settings, ifc, multiprocessing.cpu_count(), include=elements)
                it.set_cache(cache)
                for elem in self.yield_from_iterator(it):
                    self.serialiser.write(elem)

-            geom_settings = ifcopenshell.geom.settings(
-                DISABLE_TRIANGULATION=True,
-            )
+            geom_settings = ifcopenshell.geom.settings(DISABLE_TRIANGULATION=True, STRICT_TOLERANCE=True)
            it = ifcopenshell.geom.iterator(geom_settings, ifc, include=[self.camera_element])
            for elem in self.yield_from_iterator(it):
                self.serialiser.write(elem)
@@ -387,7 +346,9 @@ class CreateDrawing(bpy.types.Operator):
        return svg_path

    def setup_serialiser(self, ifc):
-        self.svg_settings = ifcopenshell.geom.settings(DISABLE_TRIANGULATION=True, INCLUDE_CURVES=True)
+        self.svg_settings = ifcopenshell.geom.settings(
+            DISABLE_TRIANGULATION=True, STRICT_TOLERANCE=True, INCLUDE_CURVES=True
+        )
        self.svg_buffer = ifcopenshell.geom.serializers.buffer()
        self.serialiser = ifcopenshell.geom.serializers.svg(self.svg_buffer, self.svg_settings)
        self.serialiser.setFile(ifc)
@@ -441,13 +402,14 @@ class CreateDrawing(bpy.types.Operator):
        # https://stackoverflow.com/questions/36018627/sorting-child-elements-with-lxml-based-on-attribute-value
        group = root.find("{http://www.w3.org/2000/svg}g")
        # group[:] = sorted(group, key=lambda e : "projection" in e.get("class"))
-        group[:] = reversed(group)
+        if group:
+            group[:] = reversed(group)

    def canonicalise_class_name(self, name):
        return re.sub("[^0-9a-zA-Z]+", "", name)

    def generate_annotation(self, context):
-        if not self.props.has_annotation:
+        if not self.cprops.has_annotation:
            return
        svg_path = os.path.join(context.scene.BIMProperties.data_dir, "cache", self.drawing_name + "-annotation.svg")
        if os.path.isfile(svg_path) and self.props.should_use_annotation_cache:
@@ -456,9 +418,7 @@ class CreateDrawing(bpy.types.Operator):
        camera = self.camera
        svg_writer = svgwriter.SvgWriter()

-        drawing_style = context.scene.DocProperties.drawing_styles[
-            camera.data.BIMCameraProperties.active_drawing_style_index
-        ]
+        drawing_style = context.scene.DocProperties.drawing_styles[self.cprops.active_drawing_style_index]

        render = context.scene.render
        if self.is_landscape(render):
@@ -478,40 +438,9 @@ class CreateDrawing(bpy.types.Operator):
        svg_writer.camera_height = height
        svg_writer.camera_projection = tuple(camera.matrix_world.to_quaternion() @ Vector((0, 0, -1)))

-        for obj in camera.users_collection[0].objects:
-            if "IfcAnnotation/" not in obj.name:
-                continue
-            element = tool.Ifc.get_entity(obj)
-            if element.ObjectType == "GRID":
-                svg_writer.annotations.setdefault("grid_objs", []).append(obj)
-            elif obj.type == "CAMERA":
-                continue
-            elif element.ObjectType == "TEXT_LEADER":
-                svg_writer.annotations.setdefault("leader_objs", []).append(obj)
-            elif element.ObjectType == "STAIR_ARROW":
-                svg_writer.annotations["stair_obj"] = obj
-            elif element.ObjectType == "EQUAL_DIMENSION":
-                svg_writer.annotations.setdefault("equal_objs", []).append(obj)
-            elif element.ObjectType == "DIMENSION":
-                svg_writer.annotations.setdefault("dimension_objs", []).append(obj)
-            elif element.ObjectType == "BREAKLINE":
-                svg_writer.annotations["break_obj"] = obj
-            elif element.ObjectType == "HIDDEN_LINE":
-                svg_writer.annotations.setdefault("hidden_objs", []).append((obj, obj.data))
-            elif element.ObjectType == "SOLID_LINE":
-                svg_writer.annotations.setdefault("solid_objs", []).append((obj, obj.data))
-            elif element.ObjectType == "PLAN_LEVEL":
-                svg_writer.annotations.setdefault("plan_level_objs", []).append(obj)
-            elif element.ObjectType == "SECTION_LEVEL":
-                svg_writer.annotations["section_level_obj"] = obj
-            elif element.ObjectType == "TEXT":
-                svg_writer.annotations.setdefault("text_objs", []).append(obj)
-            elif element.ObjectType == "MISC":
-                svg_writer.annotations.setdefault("misc_objs", []).append(obj)
-
-        svg_writer.annotations["attributes"] = [a.name for a in drawing_style.attributes]
-        # TODO: This was the old 2D annotation box checking system, prepare to deprecate
-        svg_writer.annotations["annotation_objs"] = []
+        elements = tool.Drawing.get_group_elements(tool.Drawing.get_drawing_group(self.camera_element))
+        svg_writer.annotations = sorted(elements, key=lambda a: tool.Drawing.get_annotation_z_index(a))
+        svg_writer.metadata = tool.Drawing.get_drawing_metadata(self.camera_element)

        svg_writer.write("annotation")
        return svg_writer.output
@@ -562,7 +491,7 @@ class CreateDrawing(bpy.types.Operator):
        return "mat-" + str(element.id())


-class AddAnnotation(bpy.types.Operator):
+class AddAnnotation(bpy.types.Operator, Operator):
    bl_idname = "bim.add_annotation"
    bl_label = "Add Annotation"
    bl_options = {"REGISTER", "UNDO"}
@@ -573,92 +502,37 @@ class AddAnnotation(bpy.types.Operator):
    def poll(cls, context):
        return IfcStore.get_file() and context.scene.camera

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        context.scene.DocProperties.should_draw_decorations = True
-        subcontext = ifcopenshell.util.representation.get_context(
-            IfcStore.get_file(), "Plan", "Annotation", context.scene.camera.data.BIMCameraProperties.target_view
-        )
-        if not subcontext:
-            return {"FINISHED"}
-        # TODO: reimplement bulk smart tagging
-        # if self.data_type == "text":
-        #    if context.selected_objects:
-        #        for selected_object in context.selected_objects:
-        #            obj = annotation.Annotator.add_text(context, related_element=selected_object)
-        #    else:
-        #        obj = annotation.Annotator.add_text(context)
-        # else:
-        obj = annotation.Annotator.get_annotation_obj(self.object_type, self.data_type, context)
-        if self.object_type == "BREAKLINE":
-            obj = annotation.Annotator.add_plane_to_annotation(obj, context)
-        elif self.object_type != "TEXT":
-            obj = annotation.Annotator.add_line_to_annotation(obj, context)
-
-        if not obj.BIMObjectProperties.ifc_definition_id:
-            ifc_representation_class = ""
-            if self.object_type == "TEXT":
-                ifc_representation_class = "IfcTextLiteral"
-            elif self.object_type == "TEXT_LEADER":
-                ifc_representation_class = "IfcGeometricCurveSet/IfcTextLiteral"
-            bpy.ops.bim.assign_class(
-                obj=obj.name,
-                ifc_class="IfcAnnotation",
-                context_id=subcontext.id(),
-                ifc_representation_class=ifc_representation_class,
-            )
-            element = tool.Ifc.get_entity(obj)
-            element.ObjectType = self.object_type
-            camera = tool.Ifc.get_entity(context.scene.camera)
-            group = [r for r in camera.HasAssignments if r.is_a("IfcRelAssignsToGroup")][0].RelatingGroup
-            bpy.ops.bim.assign_group(product=obj.name, group=group.id())
-        else:
-            bpy.ops.bim.update_representation(obj=obj.name)
-
-        bpy.ops.object.select_all(action="DESELECT")
-        context.view_layer.objects.active = obj
-        obj.select_set(True)
-        if obj.data:
-            bpy.ops.object.mode_set(mode="EDIT")
-        return {"FINISHED"}
+        drawing = tool.Ifc.get_entity(context.scene.camera)
+        if not drawing:
+            return
+        core.add_annotation(tool.Ifc, tool.Collector, tool.Drawing, drawing=drawing, object_type=self.object_type)


-class AddSheet(bpy.types.Operator):
+class AddSheet(bpy.types.Operator, Operator):
    bl_idname = "bim.add_sheet"
    bl_label = "Add Sheet"
    bl_options = {"REGISTER", "UNDO"}
-    # TODO: check undo redo

-    def execute(self, context):
-        scene = context.scene
-        new = scene.DocProperties.sheets.add()
-        new.name = "{} - SHEET".format(len(scene.DocProperties.sheets))
-        sheet_builder = sheeter.SheetBuilder()
-        sheet_builder.data_dir = scene.BIMProperties.data_dir
-        sheet_builder.create(new.name, scene.DocProperties.titleblock)
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.add_sheet(tool.Ifc, tool.Drawing, titleblock=context.scene.DocProperties.titleblock)


-class OpenSheet(bpy.types.Operator):
+class OpenSheet(bpy.types.Operator, Operator):
    bl_idname = "bim.open_sheet"
    bl_label = "Open Sheet"
+    bl_options = {"REGISTER", "UNDO"}

-    def execute(self, context):
-        props = context.scene.DocProperties
-        open_with_user_command(
-            context.preferences.addons["blenderbim"].preferences.svg_command,
-            os.path.join(context.scene.BIMProperties.data_dir, "sheets", props.active_sheet.name + ".svg"),
-        )
-        return {"FINISHED"}
+    def _execute(self, context):
+        self.props = context.scene.DocProperties
+        sheet = tool.Ifc.get().by_id(self.props.sheets[self.props.active_sheet_index].ifc_definition_id)
+        core.open_sheet(tool.Drawing, sheet=sheet)


 class AddDrawingToSheet(bpy.types.Operator):
    bl_idname = "bim.add_drawing_to_sheet"
    bl_label = "Add Drawing To Sheet"
    bl_options = {"REGISTER", "UNDO"}
-    # TODO: check undo redo

    @classmethod
    def poll(cls, context):
@@ -667,9 +541,69 @@ class AddDrawingToSheet(bpy.types.Operator):

    def execute(self, context):
        props = context.scene.DocProperties
+        active_drawing = props.drawings[props.active_drawing_index]
+        active_sheet = props.sheets[props.active_sheet_index]
+        drawing = tool.Ifc.get().by_id(active_drawing.ifc_definition_id)
+        sheet = tool.Ifc.get().by_id(active_sheet.ifc_definition_id)
+        if not sheet.is_a("IfcDocumentInformation"):
+            return {"FINISHED"}
+
+        if tool.Ifc.get_schema() == "IFC2X3":
+            references = sheet.DocumentReferences or []
+        else:
+            references = sheet.HasDocumentReferences or []
+
+        has_drawing = False
+        for reference in references:
+            if tool.Ifc.get_schema() == "IFC2X3":
+                element = [r for r in tool.Ifc.by_type("IfcRelAssociatesDocument") if r.RelatingDocument == reference][
+                    0
+                ].RelatedObjects[0]
+            else:
+                element = reference.DocumentRefForObjects[0].RelatedObjects[0]
+            if element == drawing:
+                has_drawing = True
+                break
+
+        if has_drawing:
+            return {"FINISHED"}
+
+        reference = tool.Ifc.run("document.add_reference", information=sheet)
+        if tool.Ifc.get_schema() == "IFC2X3":
+            attributes = {"ItemReference": str(len(sheet.DocumentReferences or []))}
+        else:
+            attributes = {"Identification": str(len(sheet.HasDocumentReferences or []))}
+        tool.Ifc.run("document.edit_reference", reference=reference, attributes=attributes)
+        tool.Ifc.run("document.assign_document", product=drawing, document=reference)
        sheet_builder = sheeter.SheetBuilder()
        sheet_builder.data_dir = context.scene.BIMProperties.data_dir
-        sheet_builder.add_drawing(props.active_drawing.name, props.active_sheet.name)
+        sheet_builder.add_drawing(reference, drawing, sheet)
+
+        tool.Drawing.import_sheets()
+        return {"FINISHED"}
+
+
+class RemoveDrawingFromSheet(bpy.types.Operator):
+    bl_idname = "bim.remove_drawing_from_sheet"
+    bl_label = "Remove Drawing From Sheet"
+    bl_options = {"REGISTER", "UNDO"}
+    reference: bpy.props.IntProperty()
+
+    def execute(self, context):
+        reference = tool.Ifc.get().by_id(self.reference)
+        sheet = tool.Drawing.get_reference_document(reference)
+
+        sheet_builder = sheeter.SheetBuilder()
+        sheet_builder.data_dir = context.scene.BIMProperties.data_dir
+        sheet_builder.remove_drawing(reference, sheet)
+
+        drawing = tool.Drawing.get_reference_element(reference)
+        if drawing:
+            tool.Ifc.run("document.unassign_document", product=drawing, document=reference)
+
+        tool.Ifc.run("document.remove_reference", reference=reference)
+
+        tool.Drawing.import_sheets()
        return {"FINISHED"}


@@ -685,10 +619,16 @@ class CreateSheets(bpy.types.Operator):
    def execute(self, context):
        scene = context.scene
        props = scene.DocProperties
-        name = props.active_sheet.name
+        active_sheet = props.sheets[props.active_sheet_index]
+        sheet = tool.Ifc.get().by_id(active_sheet.ifc_definition_id)
+
+        if not sheet.is_a("IfcDocumentInformation"):
+            return {"FINISHED"}
+
+        name = os.path.splitext(os.path.basename(tool.Drawing.get_document_uri(sheet)))[0]
        sheet_builder = sheeter.SheetBuilder()
        sheet_builder.data_dir = scene.BIMProperties.data_dir
-        sheet_builder.build(name)
+        sheet_builder.build(sheet)

        svg2pdf_command = context.preferences.addons["blenderbim"].preferences.svg2pdf_command
        svg2dxf_command = context.preferences.addons["blenderbim"].preferences.svg2dxf_command
@@ -738,40 +678,14 @@ class OpenView(bpy.types.Operator):
        return {"FINISHED"}


-class OpenViewCamera(bpy.types.Operator):
-    """Select this drawing's camera object and expand its drawing properties"""
-
-    bl_idname = "bim.open_view_camera"
-    bl_label = "Open View Camera"
-    bl_options = {"REGISTER", "UNDO"}
-    view_name: bpy.props.StringProperty()
-
-    @classmethod
-    def poll(cls, context):
-        return context.mode == "OBJECT"
-
-    def execute(self, context):
-        doc_props = context.scene.DocProperties
-        doc_props.active_drawing_index = doc_props.drawings.find(self.view_name)
-        drawing = doc_props.active_drawing
-        bpy.ops.object.select_all(action="DESELECT")
-        drawing.camera.select_set(True)
-        context.view_layer.objects.active = drawing.camera
-        for area in context.screen.areas:
-            if area.ui_type == "PROPERTIES":
-                for space in area.spaces:
-                    space.context = "DATA"
-        return {"FINISHED"}
-
-
 class ActivateView(bpy.types.Operator):
    bl_idname = "bim.activate_view"
    bl_label = "Activate View"
    bl_options = {"REGISTER", "UNDO"}
-    drawing_index: bpy.props.IntProperty()
+    drawing: bpy.props.IntProperty()

    def execute(self, context):
-        camera = context.scene.DocProperties.drawings[self.drawing_index].camera
+        camera = tool.Ifc.get_object(tool.Ifc.get().by_id(self.drawing))
        if not camera:
            return {"FINISHED"}
        area = next(area for area in context.screen.areas if area.type == "VIEW_3D")
@@ -798,7 +712,9 @@ class ActivateView(bpy.types.Operator):

                    project_collection.children["Views"].children[camera.users_collection[0].name].hide_viewport = False
        bpy.data.collections.get(camera.users_collection[0].name).hide_render = False
+        bpy.context.scene.DocProperties.active_drawing_id = self.drawing
        bpy.ops.bim.activate_drawing_style()
+        core.sync_references(tool.Ifc, tool.Collector, tool.Drawing, drawing=tool.Ifc.get().by_id(self.drawing))
        return {"FINISHED"}


@@ -819,68 +735,6 @@ class SelectDocIfcFile(bpy.types.Operator):
        return {"RUNNING_MODAL"}


-class GenerateReferences(bpy.types.Operator):
-    bl_idname = "bim.generate_references"
-    bl_label = "Generate References"
-    bl_options = {"REGISTER", "UNDO"}
-
-    def execute(self, context):
-        self.camera = context.scene.camera
-        self.filter_potential_references()
-        if self.camera.data.BIMCameraProperties.target_view == "PLAN_VIEW":
-            self.generate_grids()
-        if self.camera.data.BIMCameraProperties.target_view == "ELEVATION_VIEW":
-            self.generate_grids()
-            self.generate_levels(context)
-        if self.camera.data.BIMCameraProperties.target_view == "SECTION_VIEW":
-            self.generate_grids()
-            self.generate_levels(context)
-        return {"FINISHED"}
-
-    def filter_potential_references(self):
-        for name in ["grids", "levels"]:
-            setattr(self, name, [])
-        for obj in bpy.data.objects:
-            if "IfcGridAxis/" in obj.name:
-                self.grids.append(obj)
-            if "IfcBuildingStorey/" in obj.name:
-                self.levels.append(obj)
-
-    def generate_grids(self):
-        # TODO
-        pass
-
-    def generate_levels(self, context):
-        if self.camera.data.BIMCameraProperties.raster_x > self.camera.data.BIMCameraProperties.raster_y:
-            width = self.camera.data.ortho_scale
-            height = (
-                width / self.camera.data.BIMCameraProperties.raster_x * self.camera.data.BIMCameraProperties.raster_y
-            )
-        else:
-            height = self.camera.data.ortho_scale
-            width = (
-                height / self.camera.data.BIMCameraProperties.raster_y * self.camera.data.BIMCameraProperties.raster_x
-            )
-        level_obj = annotation.Annotator.get_annotation_obj("Section Level", "curve", context)
-
-        width_in_mm = width * 1000
-        real_world_width_in_mm = width_in_mm * scale
-        offset_in_mm = 20
-        offset_percentage = offset_in_mm / real_world_width_in_mm
-
-        for obj in self.levels:
-            projection = self.project_point_onto_camera(obj.location)
-            co1 = self.camera.matrix_world @ Vector((width / 2 - (offset_percentage * width), projection[1], -1))
-            co2 = self.camera.matrix_world @ Vector((-(width / 2), projection[1], -1))
-            annotation.Annotator.add_line_to_annotation(level_obj, context, co1, co2)
-
-    def project_point_onto_camera(self, point):
-        projection = self.camera.matrix_world.to_quaternion() @ Vector((0, 0, -1))
-        return self.camera.matrix_world.inverted() @ geometry.intersect_line_plane(
-            point.xyz, point.xyz - projection, self.camera.location, projection
-        )
-
-
 class ResizeText(bpy.types.Operator):
    bl_idname = "bim.resize_text"
    bl_label = "Resize Text"
@@ -894,21 +748,14 @@ class ResizeText(bpy.types.Operator):
        return {"FINISHED"}


-class RemoveDrawing(bpy.types.Operator):
+class RemoveDrawing(bpy.types.Operator, Operator):
    bl_idname = "bim.remove_drawing"
    bl_label = "Remove Drawing"
    bl_options = {"REGISTER", "UNDO"}
-    index: bpy.props.IntProperty()
+    drawing: bpy.props.IntProperty()

-    def execute(self, context):
-        props = context.scene.DocProperties
-        camera = props.drawings[self.index].camera
-        collection = camera.users_collection[0]
-        for obj in collection.objects:
-            bpy.data.objects.remove(obj)
-        bpy.data.collections.remove(collection, do_unlink=True)
-        props.drawings.remove(self.index)
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.remove_drawing(tool.Ifc, tool.Drawing, drawing=tool.Ifc.get().by_id(self.drawing))


 class AddDrawingStyle(bpy.types.Operator):
@@ -1057,75 +904,66 @@ class EditVectorStyle(bpy.types.Operator):
        return {"FINISHED"}


-class RemoveSheet(bpy.types.Operator):
+class RemoveSheet(bpy.types.Operator, Operator):
    bl_idname = "bim.remove_sheet"
    bl_label = "Remove Sheet"
    bl_options = {"REGISTER", "UNDO"}
-    index: bpy.props.IntProperty()
+    sheet: bpy.props.IntProperty()

-    def execute(self, context):
-        props = context.scene.DocProperties
-        props.sheets.remove(self.index)
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.remove_sheet(tool.Ifc, tool.Drawing, sheet=tool.Ifc.get().by_id(self.sheet))


-class AddSchedule(bpy.types.Operator):
+class AddSchedule(bpy.types.Operator, Operator):
    bl_idname = "bim.add_schedule"
    bl_label = "Add Schedule"
    bl_options = {"REGISTER", "UNDO"}
-
-    def execute(self, context):
-        new = context.scene.DocProperties.schedules.add()
-        new.name = "SCHEDULE {}".format(len(context.scene.DocProperties.schedules))
-        return {"FINISHED"}
-
-
-class RemoveSchedule(bpy.types.Operator):
-    bl_idname = "bim.remove_schedule"
-    bl_label = "Remove Schedule"
-    bl_options = {"REGISTER", "UNDO"}
-    index: bpy.props.IntProperty()
-
-    def execute(self, context):
-        props = context.scene.DocProperties
-        props.schedules.remove(self.index)
-        return {"FINISHED"}
-
-
-class SelectScheduleFile(bpy.types.Operator):
-    bl_idname = "bim.select_schedule_file"
-    bl_label = "Select Documentation IFC File"
-    bl_options = {"REGISTER", "UNDO"}
    filepath: bpy.props.StringProperty(subtype="FILE_PATH")
-    filter_glob: bpy.props.StringProperty(default="*.ods", options={"HIDDEN"})
-    index: bpy.props.IntProperty()
+    filter_glob: bpy.props.StringProperty(default="*.ods;*.xls;*.xlsx", options={"HIDDEN"})
+    use_relative_path: bpy.props.BoolProperty(name="Use Relative Path", default=False)

-    def execute(self, context):
-        props = context.scene.DocProperties
-        props.active_schedule.file = self.filepath
-        return {"FINISHED"}
+    def _execute(self, context):
+        filepath = self.filepath
+        if self.use_relative_path:
+            filepath = os.path.relpath(filepath, bpy.path.abspath("//"))
+        core.add_schedule(
+            tool.Ifc,
+            tool.Drawing,
+            uri=filepath,
+        )

    def invoke(self, context, event):
        context.window_manager.fileselect_add(self)
        return {"RUNNING_MODAL"}


-class BuildSchedule(bpy.types.Operator):
+class RemoveSchedule(bpy.types.Operator, Operator):
+    bl_idname = "bim.remove_schedule"
+    bl_label = "Remove Schedule"
+    bl_options = {"REGISTER", "UNDO"}
+    schedule: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.remove_schedule(tool.Ifc, tool.Drawing, schedule=tool.Ifc.get().by_id(self.schedule))
+
+
+class OpenSchedule(bpy.types.Operator, Operator):
+    bl_idname = "bim.open_schedule"
+    bl_label = "Open Schedule"
+    bl_options = {"REGISTER", "UNDO"}
+    schedule: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.open_schedule(tool.Drawing, schedule=tool.Ifc.get().by_id(self.schedule))
+
+
+class BuildSchedule(bpy.types.Operator, Operator):
    bl_idname = "bim.build_schedule"
    bl_label = "Build Schedule"
+    schedule: bpy.props.IntProperty()

-    @classmethod
-    def poll(cls, context):
-        return context.scene.DocProperties.active_schedule.file
-
-    def execute(self, context):
-        props = context.scene.DocProperties
-        schedule = props.active_schedule
-        schedule_creator = scheduler.Scheduler()
-        outfile = os.path.join(context.scene.BIMProperties.data_dir, "schedules", schedule.name + ".svg")
-        schedule_creator.schedule(schedule.file, outfile)
-        open_with_user_command(context.preferences.addons["blenderbim"].preferences.svg_command, outfile)
-        return {"FINISHED"}
+    def _execute(self, context):
+        core.build_schedule(tool.Drawing, schedule=tool.Ifc.get().by_id(self.schedule))


 class AddScheduleToSheet(bpy.types.Operator):
@@ -1141,9 +979,40 @@ class AddScheduleToSheet(bpy.types.Operator):

    def execute(self, context):
        props = context.scene.DocProperties
+        active_schedule = props.schedules[props.active_schedule_index]
+        active_sheet = props.sheets[props.active_sheet_index]
+        schedule = tool.Ifc.get().by_id(active_schedule.ifc_definition_id)
+        sheet = tool.Ifc.get().by_id(active_sheet.ifc_definition_id)
+        if not sheet.is_a("IfcDocumentInformation"):
+            return {"FINISHED"}
+
+        if tool.Ifc.get_schema() == "IFC2X3":
+            references = sheet.DocumentReferences or []
+        else:
+            references = sheet.HasDocumentReferences or []
+
+        has_schedule = False
+        for reference in references:
+            if reference.Location == tool.Drawing.get_schedule_location(schedule):
+                has_schedule = True
+                break
+
+        if has_schedule:
+            return {"FINISHED"}
+
+        reference = tool.Ifc.run("document.add_reference", information=sheet)
+        if tool.Ifc.get_schema() == "IFC2X3":
+            attributes = {"ItemReference": str(len(sheet.DocumentReferences or []))}
+        else:
+            attributes = {"Identification": str(len(sheet.HasDocumentReferences or []))}
+        attributes["Location"] = tool.Drawing.get_schedule_location(schedule)
+        tool.Ifc.run("document.edit_reference", reference=reference, attributes=attributes)
+
        sheet_builder = sheeter.SheetBuilder()
        sheet_builder.data_dir = context.scene.BIMProperties.data_dir
-        sheet_builder.add_schedule(props.active_schedule.name, props.active_sheet.name)
+        sheet_builder.add_schedule(reference, schedule, sheet)
+
+        tool.Drawing.import_sheets()
        return {"FINISHED"}


@@ -1170,23 +1039,6 @@ class RemoveDrawingStyleAttribute(bpy.types.Operator):
        return {"FINISHED"}


-class RefreshDrawingList(bpy.types.Operator):
-    bl_idname = "bim.refresh_drawing_list"
-    bl_label = "Refresh Drawing List"
-
-    def execute(self, context):
-        doc_props = context.scene.DocProperties
-        doc_props.drawings.clear()
-        for obj in context.scene.objects:
-            if not isinstance(obj.data, bpy.types.Camera):
-                continue
-            if "IfcAnnotation/" in obj.name:
-                new = doc_props.drawings.add()
-                new.name = "/".join(obj.name.split("/")[1:])
-                new.camera = obj
-        return {"FINISHED"}
-
-
 class CleanWireframes(bpy.types.Operator):
    bl_idname = "bim.clean_wireframes"
    bl_label = "Clean Wireframes"
@@ -1213,8 +1065,10 @@ class CopyGrid(bpy.types.Operator):
        return helper.get_active_drawing(context.scene)[0] is not None

    def execute(self, context):
+        drawing = tool.Ifc.get_entity(context.scene.camera)
+        target_view = tool.Drawing.get_drawing_target_view(drawing)
        subcontext = ifcopenshell.util.representation.get_context(
-            IfcStore.get_file(), "Plan", "Annotation", context.scene.camera.data.BIMCameraProperties.target_view
+            IfcStore.get_file(), "Plan", "Annotation", target_view
        )
        if not subcontext:
            return {"FINISHED"}
@@ -1223,8 +1077,8 @@ class CopyGrid(bpy.types.Operator):
        view_coll, camera = helper.get_active_drawing(context.scene)
        is_ortho = camera.data.type == "ORTHO"
        bounds = helper.ortho_view_frame(camera.data) if is_ortho else None
-        clipping = is_ortho and camera.data.BIMCameraProperties.target_view in ("PLAN_VIEW", "REFLECTED_PLAN_VIEW")
-        elevating = is_ortho and camera.data.BIMCameraProperties.target_view in ("ELEVATION_VIEW", "SECTION_VIEW")
+        clipping = is_ortho and target_view in ("PLAN_VIEW", "REFLECTED_PLAN_VIEW")
+        elevating = is_ortho and target_view in ("ELEVATION_VIEW", "SECTION_VIEW")

        def grep(coll):
            results = []
@@ -1420,3 +1274,126 @@ class DisableEditingTextProduct(bpy.types.Operator, Operator):

    def _execute(self, context):
        core.disable_editing_text_product(tool.Drawing, obj=context.active_object)
+
+
+class LoadSheets(bpy.types.Operator, Operator):
+    bl_idname = "bim.load_sheets"
+    bl_label = "Load Sheets"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.load_sheets(tool.Drawing)
+
+
+class DisableEditingSheets(bpy.types.Operator, Operator):
+    bl_idname = "bim.disable_editing_sheets"
+    bl_label = "Disable Editing Text Product"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.disable_editing_sheets(tool.Drawing)
+
+
+class LoadSchedules(bpy.types.Operator, Operator):
+    bl_idname = "bim.load_schedules"
+    bl_label = "Load Schedules"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.load_schedules(tool.Drawing)
+
+
+class DisableEditingSchedules(bpy.types.Operator, Operator):
+    bl_idname = "bim.disable_editing_schedules"
+    bl_label = "Disable Editing Text Product"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.disable_editing_schedules(tool.Drawing)
+
+
+class LoadDrawings(bpy.types.Operator, Operator):
+    bl_idname = "bim.load_drawings"
+    bl_label = "Load Drawings"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.load_drawings(tool.Drawing)
+
+
+class DisableEditingDrawings(bpy.types.Operator, Operator):
+    bl_idname = "bim.disable_editing_drawings"
+    bl_label = "Disable Editing Text Product"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.disable_editing_drawings(tool.Drawing)
+
+
+class ExpandSheet(bpy.types.Operator):
+    bl_idname = "bim.expand_sheet"
+    bl_label = "Expand Sheet"
+    bl_options = {"REGISTER", "UNDO"}
+    sheet: bpy.props.IntProperty()
+
+    def execute(self, context):
+        props = context.scene.DocProperties
+        for sheet in [s for s in props.sheets if s.ifc_definition_id == self.sheet]:
+            sheet.is_expanded = True
+        core.load_sheets(tool.Drawing)
+        return {"FINISHED"}
+
+
+class ContractSheet(bpy.types.Operator):
+    bl_idname = "bim.contract_sheet"
+    bl_label = "Contract Sheet"
+    bl_options = {"REGISTER", "UNDO"}
+    sheet: bpy.props.IntProperty()
+
+    def execute(self, context):
+        props = context.scene.DocProperties
+        for sheet in [s for s in props.sheets if s.ifc_definition_id == self.sheet]:
+            sheet.is_expanded = False
+        core.load_sheets(tool.Drawing)
+        return {"FINISHED"}
+
+
+class ConvertEdgeToArc(bpy.types.Operator):
+    bl_idname = "bim.convert_edge_to_arc"
+    bl_label = "Convert Edge to Arc"
+    bl_options = {"REGISTER", "UNDO"}
+
+    resolution: bpy.props.IntProperty(name="Arc Resolution", min=1, default=1)
+    should_flip: bpy.props.BoolProperty(name="Flip", description="Flip arc", default=False)
+
+    def draw(self, context):
+        layout = self.layout
+        for prop in self.__class__.__annotations__.keys():
+            layout.prop(self, prop)
+
+    def execute(self, context):
+        if bpy.context.mode != "EDIT_MESH":
+            return {"CANCELLED"}
+        obj = bpy.context.active_object
+        cursor = obj.matrix_world.inverted() @ bpy.context.scene.cursor.location
+        mesh = obj.data
+        bm = bmesh.from_edit_mesh(mesh)
+        selected_verts = [v for v in bm.verts if v.select]
+        if len(selected_verts) != 2:
+            return {"CANCELLED"}
+        l1 = selected_verts[0].co - cursor
+        l2 = selected_verts[1].co - cursor
+        angle = l1.xy.angle_signed(l2.xy)
+
+        if self.should_flip:
+            if angle > 0:
+                angle = -((pi * 2) - angle)
+            else:
+                angle = (pi * 2) + angle
+
+        v = selected_verts[0]
+        bm.verts.remove(selected_verts[1])
+        bmesh.ops.spin(bm, geom=[v], axis=(0, 0, 1), cent=cursor, steps=self.resolution * 4, angle=-angle)
+        bmesh.update_edit_mesh(mesh)
+        mesh.update()
+        return {"FINISHED"}
@@ -19,11 +19,13 @@
 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
@@ -56,12 +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")
@@ -69,7 +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):
@@ -83,7 +99,8 @@ def get_diagram_scales(self, context):
            diagram_scales_enum = [
                ("CUSTOM", "Custom", ""),
                ("1'=1'-0\"|1/1", "1'=1'-0\"", ""),
-                ('6"=1\'-0"|1/6', '6"=1\'-0"', ""),
+                ('6"=1\'-0"|1/2', '6"=1\'-0"', ""),
+                ('3"=1\'-0"|1/4', '3"=1\'-0"', ""),
                ('1-1/2"=1\'-0"|1/8', '1-1/2"=1\'-0"', ""),
                ('1"=1\'-0"|1/12', '1"=1\'-0"', ""),
                ('3/4"=1\'-0"|1/16', '3/4"=1\'-0"', ""),
@@ -132,31 +149,47 @@ 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_schedule_name(self, context):
+    schedule = tool.Ifc.get().by_id(self.ifc_definition_id)
+    core.update_schedule_name(tool.Ifc, tool.Drawing, schedule=schedule, name=self.name)
+
+
+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


@@ -198,13 +231,15 @@ 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):
-    name: StringProperty(name="Name")
-    file: StringProperty(name="File")
+    ifc_definition_id: IntProperty(name="IFC Definition ID")
+    name: StringProperty(name="Name", update=update_schedule_name)
+    identification: StringProperty(name="Identification")


 class Sheet(PropertyGroup):
@@ -218,9 +253,12 @@ 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):
@@ -269,19 +307,33 @@ 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)
+    is_editing_schedules: BoolProperty(name="Is Editing Schedules", 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)
@@ -291,51 +343,18 @@ class DocProperties(PropertyGroup):
        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)
    raster_y: IntProperty(name="Raster Y", default=1000)
    is_nts: BoolProperty(name="Is NTS")
-    cut_objects: EnumProperty(
-        items=[
-            (
-                ".IfcWall|.IfcSlab|.IfcCurtainWall|.IfcStair|.IfcStairFlight|.IfcColumn|.IfcBeam|.IfcMember|.IfcCovering|.IfcSpace",
-                "Overall Plan / Section",
-                "",
-            ),
-            (".IfcElement", "Detail Drawing", ""),
-            ("CUSTOM", "Custom", ""),
-        ],
-        name="Cut Objects",
-    )
-    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"
@@ -373,13 +392,4 @@ class BIMTextProperties(PropertyGroup):
        update=refreshFontSize,
        name="Font Size",
    )
-    symbol: EnumProperty(
-        items=[
-            ("None", "None", ""),
-            ("rectangle-tag", "Rectangle Tag", ""),
-            ("door-tag", "Door Tag", ""),
-        ],
-        update=refreshFontSize,
-        name="Symbol",
-    )
    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

@@ -30,8 +31,7 @@ class SheetBuilder:
        self.data_dir = None
        self.scale = "NTS"

-    def create(self, name, titleblock_name):
-        sheet_path = os.path.join(self.data_dir, f"{name}.svg")
+    def create(self, sheet_path, titleblock_name):
        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 +59,16 @@ 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, reference, drawing, sheet):
+        filename = drawing.Name
+        sheet_name = os.path.splitext(os.path.basename(tool.Drawing.get_document_uri(sheet)))[0]
+        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 +77,7 @@ 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.
@@ -80,29 +85,50 @@ 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-id"] = str(reference.id())
+        view.attrib["data-drawing"] = 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 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")
+    def remove_drawing(self, reference, sheet):
+        ET.register_namespace("", "http://www.w3.org/2000/svg")
+
+        sheet_path = tool.Drawing.get_document_uri(sheet)
+        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.get("data-id") == str(reference.id()):
+                sheet_root.remove(g)
+                break
+
+        sheet_tree.write(sheet_path)
+
+    def add_schedule(self, reference, schedule, sheet):
+        view_path = tool.Drawing.get_document_uri(schedule)
+        schedule_name = os.path.splitext(os.path.basename(view_path))[0]
+        sheet_path = tool.Drawing.get_document_uri(sheet)

        ET.register_namespace("", "http://www.w3.org/2000/svg")
        ET.register_namespace("xlink", "http://www.w3.org/1999/xlink")
@@ -115,30 +141,35 @@ class SheetBuilder:
        view_width = self.convert_to_mm(view_root.attrib.get("width"))
        view_height = self.convert_to_mm(view_root.attrib.get("height"))

-        group = ET.SubElement(sheet_root, "g")
-        group.attrib["data-type"] = "schedule"
+        view = ET.SubElement(sheet_root, "g")
+        view.attrib["data-type"] = "schedule"
+        view.attrib["data-id"] = str(reference.id())
+        view.attrib["data-schedule"] = str(schedule.id())

-        foreground = ET.SubElement(group, "image")
+        foreground = ET.SubElement(view, "image")
+        foreground.attrib["data-type"] = "table"
        foreground.attrib["xlink:href"] = "../schedules/{}.svg".format(schedule_name)
        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, group)
+        self.add_view_title(30, view_height + 35, view)
        sheet_tree.write(sheet_path)

    def add_view_title(self, x, y, parent):
        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 = os.path.splitext(os.path.basename(tool.Drawing.get_document_uri(sheet)))[0]
        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")
@@ -149,68 +180,86 @@ 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_schedules(root.findall('{http://www.w3.org/2000/svg}g[@data-type="schedule"]'))
+        self.build_titleblock(root, sheet)
+        self.build_drawings(root, sheet)
+        self.build_schedules(root)

        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 = os.path.splitext(os.path.basename(tool.Drawing.get_document_uri(sheet)))[0]
+
+        for view in root.findall('{http://www.w3.org/2000/svg}g[@data-type="drawing"]'):
+            reference = tool.Ifc.get().by_id(int(view.attrib["data-id"]))
+            drawing = tool.Ifc.get().by_id(view.attrib["data-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, root):
+        for view in root.findall('{http://www.w3.org/2000/svg}g[@data-type="schedule"]'):
+            reference = tool.Ifc.get().by_id(int(view.attrib["data-id"]))
+            schedule = tool.Ifc.get().by_id(int(view.attrib["data-schedule"]))

-    def build_schedules(self, schedules):
-        for group in schedules:
-            images = group.findall("{http://www.w3.org/2000/svg}image")
-            schedule = images[0]
-            group_title = images[1]
-            self.scale = "NTS"
+            images = view.findall("{http://www.w3.org/2000/svg}image")

-            group.append(self.parse_embedded_svg(schedule, {}))
-
-            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}
-                )
-            )
+            table = None
+            view_title = None

            for image in images:
-                group.remove(image)
+                if image.attrib["data-type"] == "table":
+                    table = image
+                elif image.attrib["data-type"] == "view-title":
+                    view_title = image

-            self.group_number += 1
+            if table is not None:
+                view.append(self.parse_embedded_svg(table, {}))
+
+            if view_title is not None:
+                path = self.get_href(table)
+                data = reference.get_info()
+                if not data["Name"]:
+                    data["Name"] = schedule.Name or "Unnamed"
+                view.append(self.parse_embedded_svg(view_title, data))
+
+            for image in images:
+                view.remove(image)

    def get_href(self, element):
        return urllib.parse.unquote(element.attrib.get("{http://www.w3.org/1999/xlink}href"))
@@ -24,6 +24,7 @@ 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
@@ -64,7 +65,8 @@ class SvgWriter:
        self.data_dir = None
        self.vector_style = None
        self.human_scale = "NTS"
-        self.annotations = {}
+        self.annotations = []
+        self.metadata = []
        self.background_image = None
        self.scale = 1 / 100  # 1:100

@@ -139,182 +141,169 @@ class SvgWriter:
                self.draw_line(element, "background")

    def draw_annotations(self):
-        x_offset = self.raw_width / 2
-        y_offset = self.raw_height / 2
+        for element in self.annotations:
+            obj = tool.Ifc.get_object(element)
+            if not obj or element.ObjectType == "DRAWING":
+                continue
+            elif element.ObjectType == "GRID":
+                self.draw_grid_annotation(obj)
+            elif element.ObjectType == "TEXT_LEADER":
+                self.draw_leader_annotation(obj)
+            elif element.ObjectType == "STAIR_ARROW":
+                self.draw_stair_annotation(obj)
+            elif element.ObjectType == "DIMENSION":
+                self.draw_dimension_annotations(obj)
+            elif element.ObjectType == "RADIUS":
+                self.draw_radius_annotations(obj)
+            elif element.ObjectType == "DIAMETER":
+                self.draw_diameter_annotations(obj)
+            elif element.ObjectType == "ELEVATION":
+                self.draw_elevation_annotation(obj)
+            elif element.ObjectType == "SECTION":
+                self.draw_section_annotation(obj)
+            elif element.ObjectType == "BREAKLINE":
+                self.draw_break_annotations(obj)
+            elif element.ObjectType == "HIDDEN_LINE":
+                self.draw_line_annotation(obj)
+            elif element.ObjectType == "PLAN_LEVEL":
+                self.draw_plan_level_annotation(obj)
+            elif element.ObjectType == "SECTION_LEVEL":
+                self.draw_section_level_annotation(obj)
+            elif element.ObjectType == "TEXT":
+                self.draw_text_annotation(obj, obj.location)
+            else:
+                self.draw_misc_annotation(obj)

-        for obj in self.annotations.get("equal_objs", []):
-            self.draw_dimension_annotations(obj, text_override="EQ")
-        for obj in self.annotations.get("dimension_objs", []):
-            self.draw_dimension_annotations(obj)
+        # Experimental integration with the MeasureIt-ARCH Add-on
        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
-            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)
-                v1 = self.project_point_onto_camera(v1_global)
-                start = Vector(((x_offset + v0.x), (y_offset - v0.y)))
-                end = Vector(((x_offset + v1.x), (y_offset - v1.y)))
-                vector = end - start
-                line = self.svg.add(
-                    self.svg.line(
-                        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 = tool.Ifc.get_entity(grid_obj).Name
-                self.svg.add(
-                    self.svg.text(
-                        axis_tag,
-                        insert=tuple(start * self.scale),
-                        **{
-                            "font-size": annotation.Annotator.get_svg_text_size(5.0),
-                            "font-family": "OpenGost Type B TT",
-                            "text-anchor": "middle",
-                            "alignment-baseline": "middle",
-                            "dominant-baseline": "middle",
-                        },
-                    )
-                )
-                self.svg.add(
-                    self.svg.text(
-                        axis_tag,
-                        insert=tuple(end * self.scale),
-                        **{
-                            "font-size": annotation.Annotator.get_svg_text_size(5.0),
-                            "font-family": "OpenGost Type B TT",
-                            "text-anchor": "middle",
-                            "alignment-baseline": "middle",
-                            "dominant-baseline": "middle",
-                        },
-                    )
-                )
-
-        self.draw_ifc_annotation()
-
-        for obj in self.annotations.get("misc_objs", []):
-            self.draw_misc_annotation(obj, ["IfcAnnotation"])
-
-        for obj_data in self.annotations.get("hidden_objs", []):
-            self.draw_line_annotation(obj_data, ["hidden"])
-
-        for obj_data in self.annotations.get("solid_objs", []):
-            self.draw_line_annotation(obj_data, ["solid"])
-
-        self.draw_leader_annotations()
-
-        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
-            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(
-                    [
-                        "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-start"] = "url(#section-level-marker)"
-                path["stroke-dasharray"] = "12.5, 3, 3, 3"
-                text_position = Vector(
-                    (
-                        (x_offset + projected_points[0].x) * self.scale,
-                        ((y_offset - projected_points[0].y) * self.scale) - 3.5,
-                    )
-                )
-                # TODO: allow metric to be configurable
-                rl = (matrix_world @ points[0].co.xyz).z
-                if bpy.context.scene.unit_settings.system == "IMPERIAL":
-                    rl = helper.format_distance(rl)
-                else:
-                    rl = "{:.3f}m".format(rl)
-                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": "start",
-                            "alignment-baseline": "baseline",
-                            "dominant-baseline": "baseline",
-                        },
-                    )
-                )
-
-        if self.annotations.get("stair_obj"):
-            matrix_world = self.annotations["stair_obj"].matrix_world
-            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(
-                    [
-                        "L {} {}".format((x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale)
-                        for p in projected_points
-                    ]
-                )
-                d = "M{}".format(d[1:])
-                start = Vector(((x_offset + projected_points[0].x), (y_offset - projected_points[0].y)))
-                next_point = Vector(((x_offset + projected_points[1].x), (y_offset - projected_points[1].y)))
-                text_position = (start * self.scale) - ((next_point - start).normalized() * 5)
-                path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))
-                self.svg.add(
-                    self.svg.text(
-                        "UP",
-                        insert=tuple(text_position),
-                        **{
-                            "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.draw_text_annotations()
-
-    def draw_ifc_annotation(self):
+    def draw_section_level_annotation(self, obj):
        x_offset = self.raw_width / 2
        y_offset = self.raw_height / 2
-        for annotation in self.annotations.get("annotation_objs", []):
-            for edge in annotation["edges"]:
-                v0_global = annotation["vertices"][edge[0]]
-                v1_global = annotation["vertices"][edge[1]]
-                v0 = self.project_point_onto_camera(v0_global)
-                v1 = self.project_point_onto_camera(v1_global)
-                start = Vector(((x_offset + v0.x), (y_offset - v0.y)))
-                end = Vector(((x_offset + v1.x), (y_offset - v1.y)))
-                vector = end - start
-                line = self.svg.add(
-                    self.svg.line(
-                        start=tuple(start * self.scale),
-                        end=tuple(end * self.scale),
-                        class_=" ".join(annotation["classes"]),
-                    )
+        matrix_world = obj.matrix_world
+        classes = self.get_attribute_classes(obj)
+        element = tool.Ifc.get_entity(obj)
+        storey = tool.Drawing.get_annotation_element(element)
+        tag = storey.Name if storey else element.Description
+        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) - 3.5,
                )
+            )
+            # TODO: allow metric to be configurable
+            rl = (matrix_world @ points[0].co.xyz).z
+            if bpy.context.scene.unit_settings.system == "IMPERIAL":
+                rl = helper.format_distance(rl)
+            else:
+                rl = "{:.3f}m".format(rl)
+            text_style = {
+                "font-size": annotation.Annotator.get_svg_text_size(2.5),
+                "font-family": "OpenGost Type B TT",
+                "text-anchor": "start",
+                "alignment-baseline": "baseline",
+                "dominant-baseline": "baseline",
+            }
+            self.svg.add(self.svg.text(f"RL +{rl}", insert=tuple(text_position), **text_style))
+            if tag:
+                self.svg.add(self.svg.text(tag, insert=(text_position[0], text_position[1] - 5), **text_style))

-    def draw_misc_annotation(self, obj, classes):
+    def draw_stair_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:])
+            start = Vector(((x_offset + projected_points[0].x), (y_offset - projected_points[0].y)))
+            next_point = Vector(((x_offset + projected_points[1].x), (y_offset - projected_points[1].y)))
+            text_position = (start * self.scale) - ((next_point - start).normalized() * 5)
+            path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))
+            self.svg.add(
+                self.svg.text(
+                    "UP",
+                    insert=tuple(text_position),
+                    **{
+                        "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",
+                    },
+                )
+            )
+
+    def draw_grid_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 edge in obj.data.edges:
+            v0_global = matrix_world @ obj.data.vertices[edge.vertices[0]].co.xyz
+            v1_global = matrix_world @ obj.data.vertices[edge.vertices[1]].co.xyz
+            v0 = self.project_point_onto_camera(v0_global)
+            v1 = self.project_point_onto_camera(v1_global)
+            start = Vector(((x_offset + v0.x), (y_offset - v0.y)))
+            end = Vector(((x_offset + v1.x), (y_offset - v1.y)))
+            vector = end - start
+            line = self.svg.add(
+                self.svg.line(start=tuple(start * self.scale), end=tuple(end * self.scale), class_=" ".join(classes))
+            )
+            line["stroke-dasharray"] = "12.5, 3, 3, 3"
+            axis_tag = tool.Ifc.get_entity(obj).Name
+            self.svg.add(
+                self.svg.text(
+                    axis_tag,
+                    insert=tuple(start * self.scale),
+                    **{
+                        "font-size": annotation.Annotator.get_svg_text_size(5.0),
+                        "font-family": "OpenGost Type B TT",
+                        "text-anchor": "middle",
+                        "alignment-baseline": "middle",
+                        "dominant-baseline": "middle",
+                    },
+                )
+            )
+            self.svg.add(
+                self.svg.text(
+                    axis_tag,
+                    insert=tuple(end * self.scale),
+                    **{
+                        "font-size": annotation.Annotator.get_svg_text_size(5.0),
+                        "font-family": "OpenGost Type B TT",
+                        "text-anchor": "middle",
+                        "alignment-baseline": "middle",
+                        "dominant-baseline": "middle",
+                    },
+                )
+            )
+
+    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
@@ -324,6 +313,7 @@ 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)
@@ -334,57 +324,31 @@ 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))
-        for attribute in self.annotations.get("attributes", []):
-            result = self.get_obj_value(obj, attribute)
-            if result:
-                classes.append(
-                    "{}-{}".format(re.sub("[^0-9a-zA-Z]+", "", attribute), re.sub("[^0-9a-zA-Z]+", "", result))
-                )
+        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 key in self.metadata:
+            value = ifcopenshell.util.selector.Selector.get_element_value(element, key)
+            if value:
+                classes.append(self.canonicalise_class_name(key) + "-" + self.canonicalise_class_name(str(value)))
        return classes

-    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
-        if "." in key and key.split(".")[0] == "type":
-            try:
-                obj = obj.BIMObjectProperties.relating_type
-            except:
-                return
-            key = ".".join(key.split(".")[1:])
-        result = obj.BIMObjectProperties.attributes.get(key)
-        if result:
-            return result.string_value
-        elif key == "Name":
-            return obj.name.split("/")[1]
-        elif "." in key:
-            pset_name, prop = key.split(".")
-            pset = obj.BIMObjectProperties.psets.get(pset_name)
-            if not pset:
-                pset = obj.BIMObjectProperties.qtos.get(pset_name)
-            if not pset:
-                return
-            result = pset.properties.get(prop)
-            if result:
-                return result.string_value
+    def canonicalise_class_name(self, name):
+        return re.sub("[^0-9a-zA-Z]+", "", name)

-    def draw_line_annotation(self, obj_data, classes):
+    def draw_line_annotation(self, obj):
        # 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):
-            for spline in data.splines:
+        if isinstance(obj.data, bpy.types.Curve):
+            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(
@@ -395,7 +359,7 @@ class SvgWriter:
                )
                d = "M{}".format(d[1:])
                path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))
-        elif isinstance(data, bpy.types.Mesh):
+        elif isinstance(obj.data, bpy.types.Mesh):
            self.draw_edge_annotation(obj, classes)

    def draw_edge_annotation(self, obj, classes):
@@ -414,20 +378,100 @@ class SvgWriter:
                self.svg.line(start=tuple(start * self.scale), end=tuple(end * self.scale), class_=" ".join(classes))
            )

-    def draw_leader_annotations(self):
-        for obj in self.annotations.get("leader_objs", []):
-            self.draw_line_annotation((obj, obj.data), ["leader"])
-            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_leader_annotation(self, obj):
+        self.draw_line_annotation(obj)
+        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_text_annotations(self):
-        for text_obj in self.annotations.get("text_objs", []):
-            self.draw_text_annotation(text_obj, text_obj.location)
+    def draw_section_annotation(self, obj):
+        x_offset = self.raw_width / 2
+        y_offset = self.raw_height / 2
+
+        self.draw_line_annotation(obj)
+
+        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,
+                (symbol_position * self.scale)[0],
+                (symbol_position * self.scale)[1],
+            )
+
+            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
@@ -453,10 +497,9 @@ class SvgWriter:
            (text_position * self.scale)[1],
        )

-        if text_obj.BIMTextProperties.symbol != "None":
-            self.svg.add(
-                self.svg.use("#{}".format(text_obj.BIMTextProperties.symbol), insert=tuple(text_position * self.scale))
-            )
+        symbol = tool.Drawing.get_annotation_symbol(element)
+        if symbol:
+            self.svg.add(self.svg.use(f"#{symbol}", insert=tuple(text_position * self.scale)))

        if text_literal.BoxAlignment == "top-left":
            alignment_baseline = "hanging"
@@ -486,11 +529,15 @@ class SvgWriter:
            alignment_baseline = "baseline"
            text_anchor = "end"

-        text_body = text_literal.Literal
-        if text_obj.name in self.annotations.get("template_variables", {}):
-            text_body = pystache.render(text_body, self.annotations["template_variables"][text_obj.name])
+        literal = text_literal.Literal

-        for line_number, text_line in enumerate(text_body.split("\n")):
+        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,
@@ -507,14 +554,20 @@ class SvgWriter:
                )
            )

-    def draw_break_annotations(self, break_obj):
+    def draw_break_annotations(self, obj):
        x_offset = self.raw_width / 2
        y_offset = self.raw_height / 2

-        matrix_world = break_obj.matrix_world
-        for polygon in break_obj.data.polygons:
-            points = [break_obj.data.vertices[v] for v in polygon.vertices]
+        classes = self.get_attribute_classes(obj)
+        matrix_world = obj.matrix_world
+        for edge in obj.data.edges:
+            points = [obj.data.vertices[v] for v in edge.vertices]
            projected_points = [self.project_point_onto_camera(matrix_world @ p.co.xyz) for p in points]
+            projected_points = [
+                projected_points[0],
+                (projected_points[0] + projected_points[1]) / 2,
+                projected_points[1],
+            ]
            d = " ".join(
                [
                    "L {} {}".format((x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale)
@@ -522,25 +575,14 @@ class SvgWriter:
                ]
            )
            d = "M{}".format(d[1:])
-            path = self.svg.add(self.svg.path(d=d, class_=" ".join(["break"])))
-
-            break_points = [
-                projected_points[0],
-                ((projected_points[1] - projected_points[0]) / 2) + projected_points[0],
-                projected_points[1],
-            ]
-            d = " ".join(
-                ["L {} {}".format((x_offset + p.x) * self.scale, (y_offset - p.y) * self.scale) for p in break_points]
-            )
-            d = "M{}".format(d[1:])
-            path = self.svg.add(self.svg.path(d=d, class_=" ".join(["breakline"])))
+            path = self.svg.add(self.svg.path(d=d, class_=" ".join(classes)))

    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:
-            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(
@@ -551,7 +593,6 @@ class SvgWriter:
            )
            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,
@@ -582,16 +623,80 @@ class SvgWriter:
                )
            )

-    def draw_dimension_annotations(self, dimension_obj, text_override=None):
-        matrix_world = dimension_obj.matrix_world
-        for spline in dimension_obj.data.splines:
+    def draw_radius_annotations(self, obj):
+        x_offset = self.raw_width / 2
+        y_offset = self.raw_height / 2
+        classes = self.get_attribute_classes(obj)
+        element = tool.Ifc.get_entity(obj)
+        matrix_world = obj.matrix_world
+        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)))
+
+            p0 = Vector(
+                ((x_offset + projected_points[0].x) * self.scale, (y_offset - projected_points[0].y) * self.scale)
+            )
+            p1 = Vector(
+                ((x_offset + projected_points[1].x) * self.scale, (y_offset - projected_points[1].y) * self.scale)
+            )
+            text_offset = (p0 - p1).xy.normalized() * 5
+            text_position = projected_points[0]
+            text_position = Vector(
+                ((x_offset + text_position.x) * self.scale, (y_offset - text_position.y) * self.scale)
+            )
+            text_position += text_offset
+
+            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",
+            }
+
+            radius = ((matrix_world @ points[-1].co) - (matrix_world @ points[-2].co)).length
+            radius = helper.format_distance(radius)
+            tag = element.Description or f"R{radius}"
+
+            self.svg.add(self.svg.text(tag, insert=tuple(text_position), **text_style))
+
+    def draw_diameter_annotations(self, obj):
+        classes = self.get_attribute_classes(obj)
+        matrix_world = obj.matrix_world
+        element = tool.Ifc.get_entity(obj)
+        text_override = element.Description
+        for spline in obj.data.splines:
            points = self.get_spline_points(spline)
            for i, p in enumerate(points):
                if i + 1 >= len(points):
                    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, text_format=lambda x: "D" + x
+                )
+
+    def draw_dimension_annotations(self, obj):
+        classes = self.get_attribute_classes(obj)
+        matrix_world = obj.matrix_world
+        element = tool.Ifc.get_entity(obj)
+        text_override = element.Description
+        for spline in obj.data.splines:
+            points = self.get_spline_points(spline)
+            for i, p in enumerate(points):
+                if i + 1 >= len(points):
+                    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, classes, text_override)

    def draw_measureit_arch_dimension_annotations(self):
        try:
@@ -601,10 +706,11 @@ 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, text_format=lambda x: x):
        x_offset = self.raw_width / 2
        y_offset = self.raw_height / 2
        v0 = self.project_point_onto_camera(v0_global)
@@ -626,12 +732,11 @@ 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:
            text = str(dimension)
+        text = text_format(text)
        self.svg.add(
            self.svg.text(
                text,
@@ -646,6 +751,7 @@ 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),
@@ -20,7 +20,7 @@ import bpy
 import blenderbim.bim.helper
 import blenderbim.tool as tool
 from bpy.types import Panel
-from blenderbim.bim.module.drawing.data import TextData
+from blenderbim.bim.module.drawing.data import TextData, SheetsData, SchedulesData, DrawingsData


 class BIM_PT_camera(Panel):
@@ -47,13 +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()
@@ -62,20 +62,9 @@ class BIM_PT_camera(Panel):
        row = layout.row()
        row.prop(props, "is_nts")

-        row = layout.row()
-        row.operator("bim.generate_references")
        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":
-            row = layout.row()
-            row.prop(props, "cut_objects_custom")
-
        row = layout.row()
        row.prop(props, "raster_x")
        row = layout.row()
@@ -149,90 +138,130 @@ 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
-        layout.use_property_split = True
-        props = context.scene.DocProperties
+        if not SchedulesData.is_loaded:
+            SchedulesData.load()

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

-        if props.schedules:
-            row.operator("bim.build_schedule", icon="LINENUMBERS_ON", text="")
-            row.operator("bim.remove_schedule", icon="X", text="").index = props.active_schedule_index
+        if not self.props.is_editing_schedules:
+            row = self.layout.row(align=True)
+            row.label(text=f"{SchedulesData.data['total_schedules']} Schedules Found", icon="LONGDISPLAY")
+            row.operator("bim.load_schedules", text="", icon="IMPORT")
+            return

-            layout.template_list("BIM_UL_generic", "", props, "schedules", props, "active_schedule_index")
+        row = self.layout.row(align=True)
+        row.operator("bim.add_schedule", icon="ADD")
+        row.operator("bim.disable_editing_schedules", text="", icon="CANCEL")

-            row = layout.row()
-            row.prop(props.active_schedule, "file")
-            row.operator("bim.select_schedule_file", icon="FILE_FOLDER", text="")
+        if self.props.schedules:
+            if self.props.active_schedule_index < len(self.props.schedules):
+                active_schedule = self.props.schedules[self.props.active_schedule_index]
+                row = self.layout.row(align=True)
+                row.alignment = "RIGHT"
+                row.operator("bim.open_schedule", icon="URL", text="").schedule = active_schedule.ifc_definition_id
+                row.operator("bim.build_schedule", icon="LINENUMBERS_ON", text="").schedule = active_schedule.ifc_definition_id
+                row.operator("bim.remove_schedule", icon="X", text="").schedule = active_schedule.ifc_definition_id
+
+            self.layout.template_list("BIM_UL_generic", "", self.props, "schedules", self.props, "active_schedule_index")


 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):
@@ -289,28 +318,30 @@ class BIM_PT_text(Panel):

 class BIM_PT_annotation_utilities(Panel):
    bl_idname = "BIM_PT_annotation_utilities"
-    bl_label = "Drawing"
-    bl_options = {"DEFAULT_CLOSED"}
+    bl_label = "Annotation"
    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 = row.operator("bim.add_annotation", text="Dimension", icon="FIXED_SIZE")
        op.object_type = "DIMENSION"
        op.data_type = "curve"
-        op = row.operator("bim.add_annotation", text="Dim (Eq)", icon="ARROW_LEFTRIGHT")
-        op.object_type = "EQUAL_DIMENSION"
+        op = row.operator("bim.add_annotation", text="Angle", icon="DRIVER_ROTATIONAL_DIFFERENCE")
+        op.object_type = "ANGLE"
+        op.data_type = "mesh"
+
+        row = layout.row(align=True)
+        op = row.operator("bim.add_annotation", text="Radius", icon="FORWARD")
+        op.object_type = "RADIUS"
+        op.data_type = "curve"
+        op = row.operator("bim.add_annotation", text="Diameter", icon="ARROW_LEFTRIGHT")
+        op.object_type = "DIAMETER"
        op.data_type = "curve"

        row = layout.row(align=True)
@@ -341,33 +372,58 @@ class BIM_PT_annotation_utilities(Panel):
        op = row.operator("bim.add_annotation", text="Breakline", icon="FCURVE")
        op.object_type = "BREAKLINE"
        op.data_type = "mesh"
-        op = row.operator("bim.add_annotation", text="Misc", icon="MESH_MONKEY")
-        op.object_type = "MISC"
+        op = row.operator("bim.add_annotation", text="Line", icon="MESH_MONKEY")
+        op.object_type = "LINEWORK"
        op.data_type = "mesh"

-        props = context.scene.DocProperties
+        row = layout.row(align=True)
+        op = row.operator("bim.add_annotation", text="Fill Area", icon="NODE_TEXTURE")
+        op.object_type = "FILL_AREA"

        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")
+                elif item.reference_type == "SCHEDULE":
+                    row.label(text="", icon="LONGDISPLAY")
+
+            name = "{} - {}".format(item.identification or "X", item.name or "Unnamed")
+            row.label(text=name)
        else:
            layout.label(text="", translate=False)
@@ -157,6 +157,9 @@ 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
@@ -188,8 +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,
        }

@@ -202,25 +206,14 @@ class UpdateRepresentation(bpy.types.Operator):

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

-        [
-            blenderbim.core.style.add_style(tool.Ifc, tool.Style, obj=s.material)
-            for s in obj.material_slots
-            if s.material and not s.material.BIMMaterialProperties.ifc_style_id
-        ]
-
-        if isinstance(obj.data, bpy.types.Mesh) and len(obj.data.polygons):
+        if tool.Geometry.is_body_representation(new_representation):
+            [tool.Geometry.run_style_add_style(obj=mat) for mat in tool.Geometry.get_object_materials_without_styles(obj)]
            ifcopenshell.api.run(
                "style.assign_representation_styles",
                self.file,
-                **{
-                    "shape_representation": new_representation,
-                    "styles": [
-                        self.file.by_id(s.material.BIMMaterialProperties.ifc_style_id)
-                        for s in obj.material_slots
-                        if s.material
-                    ],
-                    "should_use_presentation_style_assignment": context.scene.BIMGeometryProperties.should_use_presentation_style_assignment,
-                },
+                shape_representation=new_representation,
+                styles=tool.Geometry.get_styles(obj),
+                should_use_presentation_style_assignment=context.scene.BIMGeometryProperties.should_use_presentation_style_assignment,
            )
            tool.Geometry.record_object_materials(obj)

@@ -328,8 +321,8 @@ class CopyRepresentation(bpy.types.Operator, 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)
+        element = tool.Ifc.get_entity(obj)
+        if element:
            IfcStore.delete_element(element)
            if getattr(element, "FillsVoids", None):
                self.remove_filling(element)
@@ -354,6 +347,7 @@ class OverrideDeleteTrait:
 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)

@@ -367,21 +361,29 @@ class OverrideDelete(bpy.types.Operator, OverrideDeleteTrait):
            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):
        for obj in context.selected_objects:
            self.delete_ifc_object(obj)
            bpy.data.objects.remove(obj)
+        # Required otherwise gizmos are still visible
+        context.view_layer.objects.active = None
        return {"FINISHED"}


 class OverrideOutlinerDelete(bpy.types.Operator, OverrideDeleteTrait):
    bl_idname = "outliner.delete"
    bl_label = "Delete"
+    bl_options = {"REGISTER", "UNDO"}
    hierarchy: bpy.props.BoolProperty(default=False)

    @classmethod
@@ -404,7 +406,6 @@ class OverrideOutlinerDelete(bpy.types.Operator, OverrideDeleteTrait):
            if item.bl_rna.identifier == "Collection":
                collection = bpy.data.collections.get(item.name)
                collection_data = self.get_collection_objects_and_children(collection)
-                print(collection_data)
                objects_to_delete |= collection_data["objects"]
                collections_to_delete |= collection_data["children"]
                collections_to_delete.add(collection)
@@ -452,6 +453,7 @@ class OverrideOutlinerDelete(bpy.types.Operator, OverrideDeleteTrait):
 class OverrideDuplicateMove(bpy.types.Operator):
    bl_idname = "object.duplicate_move"
    bl_label = "Duplicate Objects"
+    bl_options = {"REGISTER", "UNDO"}

    @classmethod
    def poll(cls, context):
@@ -50,7 +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"]:
@@ -119,9 +119,6 @@ class BIM_PT_gis(Panel):
                    )
                )
            )
-        elif IfcStore.get_file().schema == "IFC2X3":
-            row = self.layout.row()
-            row.label(text="Not Georeferenced")

        if Data.projected_crs:
            row = self.layout.row(align=True)
@@ -28,7 +28,7 @@ class BIM_PT_groups(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
-    bl_parent_id = "BIM_PT_utilities"
+    bl_parent_id = "BIM_PT_project_setup"

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

    def draw(self, context):
        props = context.scene.BIMLCAProperties
@@ -21,37 +21,47 @@ from . import ui, prop, operator

 classes = (
    operator.AddConstituent,
-    operator.AddDefaultMaterial,
    operator.AddLayer,
    operator.AddListItem,
    operator.AddMaterial,
+    operator.AddMaterialSet,
    operator.AddProfile,
    operator.AssignMaterial,
    operator.AssignParameterizedProfile,
    operator.CopyMaterial,
    operator.DisableEditingAssignedMaterial,
    operator.DisableEditingMaterialSetItem,
+    operator.DisableEditingMaterials,
    operator.EditAssignedMaterial,
    operator.EditMaterialSetItem,
    operator.EnableEditingAssignedMaterial,
    operator.EnableEditingMaterialSetItem,
+    operator.LoadMaterials,
    operator.RemoveConstituent,
    operator.RemoveLayer,
    operator.RemoveListItem,
    operator.RemoveMaterial,
+    operator.RemoveMaterialSet,
    operator.RemoveProfile,
    operator.ReorderMaterialSetItem,
+    operator.SelectByMaterial,
    operator.UnassignMaterial,
    operator.UnlinkMaterial,
+    prop.Material,
+    prop.BIMMaterialProperties,
    prop.BIMObjectMaterialProperties,
+    ui.BIM_PT_materials,
    ui.BIM_PT_material,
    ui.BIM_PT_object_material,
+    ui.BIM_UL_materials,
 )


 def register():
+    bpy.types.Scene.BIMMaterialProperties = bpy.props.PointerProperty(type=prop.BIMMaterialProperties)
    bpy.types.Object.BIMObjectMaterialProperties = bpy.props.PointerProperty(type=prop.BIMObjectMaterialProperties)


 def unregister():
+    del bpy.types.Scene.BIMMaterialProperties
    del bpy.types.Object.BIMObjectMaterialProperties
@@ -0,0 +1,86 @@
+# 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():
+    MaterialsData.is_loaded = False
+    ObjectMaterialData.is_loaded = False
+
+
+class MaterialsData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {
+            "total_materials": cls.total_materials(),
+            "material_types": cls.material_types(),
+        }
+        cls.is_loaded = True
+
+    @classmethod
+    def total_materials(cls):
+        if tool.Ifc.get_schema() == "IFC2X3":
+            return (
+                len(tool.Ifc.get().by_type("IfcMaterial"))
+                + len(tool.Ifc.get().by_type("IfcMaterialLayerSet"))
+                + len(tool.Ifc.get().by_type("IfcMaterialList"))
+            )
+        return (
+            len(tool.Ifc.get().by_type("IfcMaterial"))
+            + len(tool.Ifc.get().by_type("IfcMaterialConstituentSet"))
+            + len(tool.Ifc.get().by_type("IfcMaterialLayerSet"))
+            + len(tool.Ifc.get().by_type("IfcMaterialProfileSet"))
+            + len(tool.Ifc.get().by_type("IfcMaterialList"))
+        )
+
+    @classmethod
+    def material_types(cls):
+        material_types = [
+            "IfcMaterial",
+            "IfcMaterialConstituentSet",
+            "IfcMaterialLayerSet",
+            "IfcMaterialProfileSet",
+            "IfcMaterialList",
+        ]
+        if tool.Ifc.get_schema() == "IFC2X3":
+            material_types = ["IfcMaterial", "IfcMaterialLayerSet", "IfcMaterialList"]
+        return [(m, m, "") for m in material_types]
+
+
+class ObjectMaterialData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {
+            "materials": cls.materials(),
+        }
+        cls.is_loaded = True
+
+    @classmethod
+    def materials(cls):
+        return sorted([(str(m.id()), m.Name or "Unnamed", "") for m in tool.Ifc.get().by_type("IfcMaterial")], key=lambda x: x[1])
@@ -31,11 +31,32 @@ from ifcopenshell.api.material.data import Data
 from ifcopenshell.api.profile.data import Data as ProfileData


-class Operator:
-    def execute(self, context):
-        IfcStore.execute_ifc_operator(self, context)
-        blenderbim.bim.handler.refresh_ui_data()
-        return {"FINISHED"}
+class LoadMaterials(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.load_materials"
+    bl_label = "Load Materials"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.load_materials(tool.Material, context.scene.BIMMaterialProperties.material_type)
+
+
+class DisableEditingMaterials(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.disable_editing_materials"
+    bl_label = "Disable Editing Materials"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.disable_editing_materials(tool.Material)
+
+
+class SelectByMaterial(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.select_by_material"
+    bl_label = "Select By Material"
+    bl_options = {"REGISTER", "UNDO"}
+    material: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.select_by_material(tool.Material, material=tool.Ifc.get().by_id(self.material))


 class AssignParameterizedProfile(bpy.types.Operator):
@@ -68,70 +89,54 @@ class AssignParameterizedProfile(bpy.types.Operator):
        return {"FINISHED"}


-class AddDefaultMaterial(bpy.types.Operator, Operator):
-    bl_idname = "bim.add_default_material"
-    bl_label = "Add Default Material"
-    bl_options = {"REGISTER", "UNDO"}
-
-    def _execute(self, context):
-        core.add_default_material(tool.Ifc, tool.Material)
-        Data.load(IfcStore.get_file())
-
-
-class AddMaterial(bpy.types.Operator):
+class AddMaterial(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.add_material"
    bl_label = "Add Material"
    bl_options = {"REGISTER", "UNDO"}
    obj: bpy.props.StringProperty()

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
-        obj = bpy.data.materials.get(self.obj) if self.obj else context.active_object.active_material
-        self.file = IfcStore.get_file()
-        result = ifcopenshell.api.run("material.add_material", self.file, **{"name": obj.name})
-        IfcStore.link_element(result, obj)
-        if obj.BIMMaterialProperties.ifc_style_id:
-            context = ifcopenshell.util.representation.get_context(self.file, "Model", "Body", "MODEL_VIEW")
-            if context:
-                ifcopenshell.api.run(
-                    "style.assign_material_style",
-                    self.file,
-                    **{
-                        "material": result,
-                        "style": self.file.by_id(obj.BIMMaterialProperties.ifc_style_id),
-                        "context": context,
-                    },
-                )
+        obj = bpy.data.materials.get(self.obj) if self.obj else None
+        core.add_material(tool.Ifc, tool.Material, tool.Style, obj=obj)
        Data.load(IfcStore.get_file())
        material_prop_purge()
-        return {"FINISHED"}


-class RemoveMaterial(bpy.types.Operator):
+class AddMaterialSet(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.add_material_set"
+    bl_label = "Add Material Set"
+    bl_options = {"REGISTER", "UNDO"}
+    set_type: bpy.props.StringProperty()
+
+    def _execute(self, context):
+        core.add_material_set(tool.Ifc, tool.Material, set_type=self.set_type)
+        Data.load(IfcStore.get_file())
+        material_prop_purge()
+
+
+class RemoveMaterial(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.remove_material"
    bl_label = "Remove Material"
    bl_options = {"REGISTER", "UNDO"}
-    obj: bpy.props.StringProperty()
-
-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
+    material: bpy.props.IntProperty()

    def _execute(self, context):
-        obj = bpy.data.materials.get(self.obj) if self.obj else context.active_object.active_material
-        self.file = IfcStore.get_file()
-        result = ifcopenshell.api.run(
-            "material.remove_material",
-            self.file,
-            **{"material": self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)},
-        )
-        obj.BIMObjectProperties.ifc_definition_id = 0
+        core.remove_material(tool.Ifc, tool.Material, tool.Style, material=tool.Ifc.get().by_id(self.material))
        Data.load(IfcStore.get_file())
-        return {"FINISHED"}


-class UnlinkMaterial(bpy.types.Operator, Operator):
+class RemoveMaterialSet(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.remove_material_set"
+    bl_label = "Remove Material Set"
+    bl_options = {"REGISTER", "UNDO"}
+    material: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.remove_material_set(tool.Ifc, tool.Material, material=tool.Ifc.get().by_id(self.material))
+        Data.load(IfcStore.get_file())
+
+
+class UnlinkMaterial(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.unlink_material"
    bl_label = "Unlink Material"
    bl_options = {"REGISTER", "UNDO"}
@@ -18,6 +18,7 @@

 import bpy
 from ifcopenshell.api.material.data import Data
+from blenderbim.bim.module.material.data import MaterialsData, ObjectMaterialData
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.prop import StrProperty, Attribute
 from bpy.types import PropertyGroup
@@ -32,18 +33,15 @@ from bpy.props import (
    CollectionProperty,
 )

-materials_enum = []
 materialtypes_enum = []
 profileclasses_enum = []
 parameterizedprofileclasses_enum = []


 def purge():
-    global materials_enum
    global materialtypes_enum
    global profileclasses_enum
    global parameterizedprofileclasses_enum
-    materials_enum = []
    materialtypes_enum = []
    profileclasses_enum = []
    parameterizedprofileclasses_enum = []
@@ -77,12 +75,10 @@ def getParameterizedProfileClasses(self, context):
    return parameterizedprofileclasses_enum


-def getMaterials(self, context):
-    global materials_enum
-    if len(materials_enum) == 0 and IfcStore.get_file():
-        materials_enum.clear()
-        materials_enum = [(str(m_id), m["Name"], "") for m_id, m in Data.materials.items()]
-    return materials_enum
+def get_materials(self, context):
+    if not ObjectMaterialData.is_loaded:
+        ObjectMaterialData.load()
+    return ObjectMaterialData.data["materials"]


 def getMaterialTypes(self, context):
@@ -104,9 +100,28 @@ def getMaterialTypes(self, context):
    return materialtypes_enum


+def get_material_types(self, context):
+    if not MaterialsData.is_loaded:
+        MaterialsData.load()
+    return MaterialsData.data["material_types"]
+
+
+class Material(PropertyGroup):
+    name: StringProperty(name="Name")
+    ifc_definition_id: IntProperty(name="IFC Definition ID")
+    total_elements: IntProperty(name="Total Elements")
+
+
+class BIMMaterialProperties(PropertyGroup):
+    is_editing: BoolProperty(name="Is Editing", default=False)
+    material_type: EnumProperty(items=get_material_types, name="Material Type")
+    materials: CollectionProperty(name="Materials", type=Material)
+    active_material_index: IntProperty(name="Active Material Index")
+
+
 class BIMObjectMaterialProperties(PropertyGroup):
    material_type: EnumProperty(items=getMaterialTypes, name="Material Type")
-    material: EnumProperty(items=getMaterials, name="Material")
+    material: EnumProperty(items=get_materials, name="Material")
    is_editing: BoolProperty(name="Is Editing", default=False)
    material_set_usage_attributes: CollectionProperty(name="Material Set Usage Attributes", type=Attribute)
    material_set_attributes: CollectionProperty(name="Material Set Attributes", type=Attribute)
@@ -115,7 +130,7 @@ class BIMObjectMaterialProperties(PropertyGroup):
    material_set_item_profile_attributes: CollectionProperty(
        name="Material Set Item Profile Attributes", type=Attribute
    )
-    material_set_item_material: EnumProperty(items=getMaterials, name="Material")
+    material_set_item_material: EnumProperty(items=get_materials, name="Material")
    profile_classes: EnumProperty(items=getProfileClasses, name="Profile Classes")
    parameterized_profile_classes: EnumProperty(
        items=getParameterizedProfileClasses, name="Parameterized Profile Classes"
@@ -17,11 +17,62 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

 import blenderbim.bim.helper
-from bpy.types import Panel
+from bpy.types import Panel, UIList
 from ifcopenshell.api.material.data import Data
 from ifcopenshell.api.profile.data import Data as ProfileData
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.helper import draw_attributes
+from blenderbim.bim.module.material.data import MaterialsData, ObjectMaterialData
+
+
+class BIM_PT_materials(Panel):
+    bl_label = "IFC Materials"
+    bl_idname = "BIM_PT_materials"
+    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):
+        if not MaterialsData.is_loaded:
+            MaterialsData.load()
+
+        self.props = context.scene.BIMMaterialProperties
+
+        row = self.layout.row(align=True)
+        row.label(text="{} Materials Found".format(MaterialsData.data["total_materials"]), icon="MATERIAL")
+        if self.props.is_editing:
+            row.operator("bim.disable_editing_materials", text="", icon="CANCEL")
+        else:
+            row = self.layout.row(align=True)
+            row.prop(self.props, "material_type", text="")
+            row.operator("bim.load_materials", text="", icon="IMPORT")
+            return
+
+        row = self.layout.row(align=True)
+        row.alignment = "RIGHT"
+
+        if self.props.material_type == "IfcMaterial":
+            row.operator("bim.add_material", text="", icon="ADD")
+            if self.props.materials and self.props.active_material_index < len(self.props.materials):
+                material = self.props.materials[self.props.active_material_index]
+                op = row.operator("bim.select_by_material", text="", icon="RESTRICT_SELECT_OFF")
+                op.material = material.ifc_definition_id
+                row.operator("bim.remove_material", text="", icon="X").material = material.ifc_definition_id
+        else:
+            row.operator("bim.add_material_set", text="", icon="ADD").set_type = self.props.material_type
+            if self.props.materials and self.props.active_material_index < len(self.props.materials):
+                material = self.props.materials[self.props.active_material_index]
+                op = row.operator("bim.select_by_material", text="", icon="RESTRICT_SELECT_OFF")
+                op.material = material.ifc_definition_id
+                row.operator("bim.remove_material_set", text="", icon="X").material = material.ifc_definition_id
+
+        self.layout.template_list("BIM_UL_materials", "", self.props, "materials", self.props, "active_material_index")


 class BIM_PT_material(Panel):
@@ -37,11 +88,13 @@ class BIM_PT_material(Panel):

    def draw(self, context):
        row = self.layout.row(align=True)
-        if bool(context.active_object.active_material.BIMObjectProperties.ifc_definition_id):
-            row.operator("bim.remove_material", icon="X", text="Remove IFC Material")
+        material_id = context.active_object.active_material.BIMObjectProperties.ifc_definition_id
+        if bool(material_id):
+            row.operator("bim.remove_material", icon="X", text="Remove IFC Material").material = material_id
            row.operator("bim.unlink_material", icon="UNLINKED", text="")
        else:
-            row.operator("bim.add_material", icon="ADD", text="Create IFC Material")
+            op = row.operator("bim.add_material", icon="ADD", text="Create IFC Material")
+            op.obj = context.active_object.active_material.name


 class BIM_PT_object_material(Panel):
@@ -66,6 +119,9 @@ class BIM_PT_object_material(Panel):
        return True

    def draw(self, context):
+        if not ObjectMaterialData.is_loaded:
+            ObjectMaterialData.load()
+
        self.file = IfcStore.get_file()
        self.oprops = context.active_object.BIMObjectProperties
        self.props = context.active_object.BIMObjectMaterialProperties
@@ -77,10 +133,10 @@ class BIM_PT_object_material(Panel):
            ProfileData.load(self.file)
        self.product_data = Data.products[self.oprops.ifc_definition_id]

-        if not Data.materials:
+        if not ObjectMaterialData.data["materials"]:
            row = self.layout.row(align=True)
            row.label(text="No Materials Available")
-            row.operator("bim.add_default_material", icon="ADD", text="")
+            row.operator("bim.add_material", icon="ADD", text="").obj = ""
            return

        if self.product_data:
@@ -333,3 +389,13 @@ class BIM_PT_object_material(Panel):
        if total_thickness:
            row = self.layout.row(align=True)
            row.label(text=f"Total Thickness: {total_thickness:.3f}")
+
+
+class BIM_UL_materials(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.name)
+            row2 = row.row()
+            row2.alignment = "RIGHT"
+            row2.label(text=str(item.total_elements))
@@ -47,3 +47,5 @@ class BIM_PT_misc_utilities(bpy.types.Panel):
        row.operator("bim.get_connected_system_elements")
        row = layout.row()
        row.operator("bim.draw_system_arrows")
+        row = layout.row()
+        row.operator("bim.clean_wireframes")
@@ -39,7 +39,12 @@ class AuthoringData:
    @classmethod
    def ifc_classes(cls):
        results = []
-        classes = {e.is_a() for e in tool.Ifc.get().by_type("IfcElementType")}
+        classes = {
+            e.is_a()
+            for e in tool.Ifc.get().by_type("IfcElementType")
+            + tool.Ifc.get().by_type("IfcDoorStyle")
+            + tool.Ifc.get().by_type("IfcWindowStyle")
+        }
        results.extend([(c, c, "") for c in sorted(classes)])
        return results

@@ -53,7 +58,7 @@ class AuthoringData:
        if not ifc_class and ifc_classes:
            ifc_class = ifc_classes[0][0]
        if ifc_class:
-            elements = [(str(e.id()), e.Name, "") for e in tool.Ifc.get().by_type(ifc_class)]
+            elements = [(str(e.id()), e.Name, e.Description or "") for e in tool.Ifc.get().by_type(ifc_class)]
            results.extend(sorted(elements, key=lambda s: s[1]))
            return results
        return []
@@ -112,7 +112,7 @@ def add_object(self, context):

 class BIM_OT_add_object(Operator):
    bl_idname = "mesh.add_grid"
-    bl_label = "Grid"
+    bl_label = "IFC Grid"
    bl_options = {"REGISTER", "UNDO"}

    u_spacing: FloatProperty(name="U Spacing", default=10)
@@ -120,6 +120,10 @@ class BIM_OT_add_object(Operator):
    v_spacing: FloatProperty(name="V Spacing", default=10)
    total_v: IntProperty(name="Number of V Grids", default=3)

+    @classmethod
+    def poll(cls, context):
+        return IfcStore.get_file()
+
    def execute(self, context):
        return IfcStore.execute_ifc_operator(self, context)

@@ -27,6 +27,7 @@ from bpy.app.handlers import persistent
@persistent
 def load_post(*args):
    ifcopenshell.api.add_pre_listener("attribute.edit_attributes", "BlenderBIM.Root.SyncName", root.sync_name)
+    ifcopenshell.api.add_pre_listener("style.edit_presentation_style", "BlenderBIM.Root.SyncStyleName", root.sync_name)

    ifcopenshell.api.add_post_listener(
        "geometry.add_representation", "BlenderBIM.Product.GenerateBox", product.generate_box
@@ -0,0 +1,108 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2020, 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 math
+import bmesh
+import ifcopenshell
+import ifcopenshell.api
+import ifcopenshell.util.unit
+import ifcopenshell.util.element
+import ifcopenshell.util.representation
+import mathutils.geometry
+import blenderbim.bim.handler
+import blenderbim.core.type
+import blenderbim.core.root
+import blenderbim.core.geometry
+import blenderbim.tool as tool
+from math import pi, degrees
+from mathutils import Vector, Matrix
+
+
+class MepGenerator:
+    def __init__(self, relating_type):
+        self.relating_type = relating_type
+
+    def generate(self):
+        self.file = tool.Ifc.get()
+        self.collection = bpy.context.view_layer.active_layer_collection.collection
+
+        if self.relating_type.is_a("IfcCableCarrierSegmentType"):
+            pass
+        elif self.relating_type.is_a("IfcCableSegmentType"):
+            pass
+        elif self.relating_type.is_a("IfcDuctSegmentType"):
+            dimensions = ifcopenshell.util.element.get_psets(self.relating_type).get("Pset_DuctSegmentTypeCommon") or {}
+            shape = dimensions.get("Shape") or dimensions.get("CrossSectionShape")
+
+            if shape == "RECTANGULAR":
+                self.width = dimensions.get("NominalDiameterOrWidth")
+                self.height = dimensions.get("NominalHeight")
+                self.length = 1
+                self.rotation = 0
+
+                return self.derive_from_cursor()
+        elif self.relating_type.is_a("IfcPipeSegmentType"):
+            pass
+
+    def derive_from_cursor(self):
+        self.location = bpy.context.scene.cursor.location
+        return self.create_rectangle_segment()
+
+    def create_rectangle_segment(self):
+        verts = [
+            Vector((0, self.width, 0)),
+            Vector((0, 0, 0)),
+            Vector((0, self.width, self.height)),
+            Vector((0, 0, self.height)),
+            Vector((self.length, self.width, 0)),
+            Vector((self.length, 0, 0)),
+            Vector((self.length, self.width, self.height)),
+            Vector((self.length, 0, self.height)),
+        ]
+        faces = [
+            [1, 3, 2, 0],
+            [4, 6, 7, 5],
+            [1, 0, 4, 5],
+            [3, 7, 6, 2],
+            [0, 2, 6, 4],
+            [1, 5, 7, 3],
+        ]
+        mesh = bpy.data.meshes.new(name="Segment")
+        mesh.from_pydata(verts, [], faces)
+
+        ifc_classes = ifcopenshell.util.type.get_applicable_entities(self.relating_type.is_a(), self.file.schema)
+        ifc_class = ifc_classes[0]
+
+        obj = bpy.data.objects.new(tool.Model.generate_occurrence_name(self.relating_type, ifc_class), mesh)
+        obj.location = self.location
+        obj.rotation_euler[2] = self.rotation
+        self.collection.objects.link(obj)
+
+        bpy.ops.bim.assign_class(
+            obj=obj.name,
+            ifc_class=ifc_class,
+            ifc_representation_class="IfcExtrudedAreaSolid/IfcRectangleProfileDef",
+        )
+
+        blenderbim.core.type.assign_type(tool.Ifc, tool.Type, element=tool.Ifc.get_entity(obj), type=self.relating_type)
+        element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        pset = ifcopenshell.api.run("pset.add_pset", self.file, product=element, name="EPset_Parametric")
+        ifcopenshell.api.run("pset.edit_pset", self.file, pset=pset, properties={"Engine": "BlenderBIM.Mep"})
+        obj.select_set(True)
+        return obj
@@ -25,7 +25,7 @@ import ifcopenshell.util.representation
 import blenderbim.tool as tool
 import blenderbim.core.type
 import blenderbim.core.geometry
-from . import wall, slab, profile
+from . import wall, slab, profile, mep
 from blenderbim.bim.ifc import IfcStore
 from ifcopenshell.api.pset.data import Data as PsetData
 from mathutils import Vector, Matrix
@@ -81,6 +81,9 @@ class AddTypeInstance(bpy.types.Operator):
        elif material and material.is_a("IfcMaterialLayerSet"):
            if self.generate_layered_element(ifc_class, relating_type):
                return {"FINISHED"}
+        if relating_type.is_a("IfcFlowSegmentType"):
+            if mep.MepGenerator(relating_type).generate():
+                return {"FINISHED"}

        building_obj = None
        if len(context.selected_objects) == 1 and context.active_object:
@@ -53,5 +53,8 @@ def update_ifc_class(self, context):
 class BIMModelProperties(PropertyGroup):
    ifc_class: bpy.props.EnumProperty(items=get_ifc_class, name="IFC Class", update=update_ifc_class)
    relating_type: bpy.props.EnumProperty(items=get_relating_type, name="Relating Type")
-    occurrence_name_style: bpy.props.EnumProperty(items=[("CLASS", "By Class", ""), ("TYPE", "By Type", ""), ("CUSTOM", "Custom", "")], name="Occurrence Name Style")
+    occurrence_name_style: bpy.props.EnumProperty(
+        items=[("CLASS", "By Class", ""), ("TYPE", "By Type", ""), ("CUSTOM", "Custom", "")],
+        name="Occurrence Name Style",
+    )
    occurrence_name_function: bpy.props.StringProperty(name="Occurrence Name Function")
@@ -17,24 +17,34 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

 import bpy
+import blenderbim.bim.handler
+import blenderbim.tool as tool
 from blenderbim.bim.ifc import IfcStore
-from ifcopenshell.api.style.data import Data as StyleData


 def sync_name(usecase_path, ifc_file, settings):
+    if usecase_path == "attribute.edit_attributes":
+        element = settings["product"]
+    elif usecase_path == "style.edit_presentation_style":
+        element = settings["style"]
+
    if "Name" not in settings["attributes"]:
        return
-    obj = IfcStore.get_element(settings["product"].id())
+    obj = tool.Ifc.get_object(element)
    if not obj:
        return
    if isinstance(obj, bpy.types.Object):
-        new_name = "{}/{}".format(settings["product"].is_a(), settings["attributes"]["Name"] or "Unnamed")
+        new_name = "{}/{}".format(element.is_a(), settings["attributes"]["Name"] or "Unnamed")
    elif isinstance(obj, bpy.types.Material):
        new_name = settings["attributes"]["Name"] or "Unnamed"
-        if obj.BIMMaterialProperties.ifc_style_id:
-            IfcStore.get_file().by_id(obj.BIMMaterialProperties.ifc_style_id).Name = new_name
-            StyleData.load(IfcStore.get_file(), obj.BIMMaterialProperties.ifc_style_id)
+        material = tool.Ifc.get_entity(obj)
+        if material and material != element:
+            material.Name = new_name
+        style = tool.Style.get_style(obj)
+        if style and style != element:
+            style.Name = new_name
    collection = bpy.data.collections.get(obj.name)
    if collection:
        collection.name = new_name
    obj.name = new_name
+    blenderbim.bim.handler.refresh_ui_data()
@@ -866,25 +866,24 @@ def calculate_quantities(usecase_path, ifc_file, settings):
    width = obj.dimensions[1] / unit_scale
    height = obj.dimensions[2] / unit_scale

-    if product.HasOpenings:
-        # TODO: calculate gross / net
-        gross_footprint_area = 0
-        net_footprint_area = 0
-        gross_side_area = 0
-        net_side_area = 0
-        gross_volume = 0
-        net_volume = 0
-    else:
-        bm = bmesh.new()
-        bm.from_mesh(obj.data)
-        bm.faces.ensure_lookup_table()
-        gross_footprint_area = sum([f.calc_area() for f in bm.faces if f.normal.z < -0.9])
-        net_footprint_area = gross_footprint_area
-        gross_side_area = sum([f.calc_area() for f in bm.faces if f.normal.y > 0.9])
-        net_side_area = gross_side_area
-        gross_volume = bm.calc_volume()
-        net_volume = gross_volume
-        bm.free()
+    bm_gross = bmesh.new()
+    bm_gross.from_mesh(obj.data)
+    bm_gross.faces.ensure_lookup_table()
+
+    bm_net = bmesh.new()
+    depsgraph = bpy.context.evaluated_depsgraph_get()
+    evaluated_mesh = obj.evaluated_get(depsgraph).data
+    bm_net.from_mesh(evaluated_mesh)
+    bm_net.faces.ensure_lookup_table()
+
+    gross_footprint_area = sum([f.calc_area() for f in bm_gross.faces if f.normal.z < -0.9])
+    net_footprint_area = sum([f.calc_area() for f in bm_net.faces if f.normal.z < -0.9])
+    gross_side_area = sum([f.calc_area() for f in bm_gross.faces if f.normal.y > 0.9])
+    net_side_area = sum([f.calc_area() for f in bm_net.faces if f.normal.y > 0.9])
+    gross_volume = bm_gross.calc_volume()
+    net_volume = bm_net.calc_volume()
+    bm_gross.free()
+    bm_net.free()

    ifcopenshell.api.run(
        "pset.edit_qto",
@@ -52,7 +52,7 @@ class BimTool(WorkSpaceTool):
    )

    def draw_settings(context, layout, tool):
-        if not AuthoringData.is_loaded:
+        if not AuthoringData.is_loaded and IfcStore.get_file():
            AuthoringData.load()

        row = layout.row(align=True)
@@ -20,6 +20,7 @@ import bpy
 from . import ui, prop, operator

 classes = (
+    operator.AddActor,
    operator.AddAddress,
    operator.AddAddressAttribute,
    operator.AddOrganisation,
@@ -28,18 +29,22 @@ classes = (
    operator.AddPersonAttribute,
    operator.AddRole,
    operator.ClearUser,
+    operator.DisableEditingActor,
    operator.DisableEditingAddress,
    operator.DisableEditingOrganisation,
    operator.DisableEditingPerson,
    operator.DisableEditingRole,
+    operator.EditActor,
    operator.EditAddress,
    operator.EditOrganisation,
    operator.EditPerson,
    operator.EditRole,
+    operator.EnableEditingActor,
    operator.EnableEditingAddress,
    operator.EnableEditingOrganisation,
    operator.EnableEditingPerson,
    operator.EnableEditingRole,
+    operator.RemoveActor,
    operator.RemoveAddress,
    operator.RemoveAddressAttribute,
    operator.RemoveOrganisation,
@@ -52,6 +57,7 @@ classes = (
    ui.BIM_PT_people,
    ui.BIM_PT_organisations,
    ui.BIM_PT_owner,
+    ui.BIM_PT_actor,
 )


@@ -24,6 +24,7 @@ def refresh():
    PeopleData.is_loaded = False
    OrganisationsData.is_loaded = False
    OwnerData.is_loaded = False
+    ActorData.is_loaded = False


 class RolesAddressesData:
@@ -202,3 +203,30 @@ class OwnerData:
                }
            )
        return results
+
+
+class ActorData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {
+            "actor": cls.actor(),
+            "actors": cls.actors(),
+        }
+        cls.is_loaded = True
+
+    @classmethod
+    def actor(cls):
+        ifc_class = bpy.context.scene.BIMOwnerProperties.actor_type
+        return [(str(p.id()), p[0] or "Unnamed", "") for p in tool.Ifc.get().by_type(ifc_class)]
+
+    @classmethod
+    def actors(cls):
+        actors = []
+        props = bpy.context.scene.BIMOwnerProperties
+        for actor in tool.Ifc.get().by_type(props.actor_class, include_subtypes=False):
+            is_editing = props.active_actor_id == actor.id()
+            actors.append({"id": actor.id(), "name": actor.Name or "Unnamed", "is_editing": is_editing})
+        return actors
@@ -306,3 +306,52 @@ class ClearUser(bpy.types.Operator, Operator):

    def _execute(self, context):
        core.clear_user(tool.Owner)
+
+
+class AddActor(bpy.types.Operator, Operator):
+    bl_idname = "bim.add_actor"
+    bl_label = "Add Actor"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        props = bpy.context.scene.BIMOwnerProperties
+        if props.actor:
+            core.add_actor(tool.Ifc, ifc_class=props.actor_class, actor=tool.Ifc.get().by_id(int(props.actor)))
+
+
+class EnableEditingActor(bpy.types.Operator, Operator):
+    bl_idname = "bim.enable_editing_actor"
+    bl_label = "Enable Editing Actor"
+    bl_options = {"REGISTER", "UNDO"}
+    actor: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.enable_editing_actor(tool.Owner, actor=tool.Ifc.get().by_id(self.actor))
+
+
+class DisableEditingActor(bpy.types.Operator, Operator):
+    bl_idname = "bim.disable_editing_actor"
+    bl_label = "Disable Editing Actor"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.disable_editing_actor(tool.Owner)
+
+
+class EditActor(bpy.types.Operator, Operator):
+    bl_idname = "bim.edit_actor"
+    bl_label = "Edit Actor"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        core.edit_actor(tool.Ifc, tool.Owner)
+
+
+class RemoveActor(bpy.types.Operator, Operator):
+    bl_idname = "bim.remove_actor"
+    bl_label = "Remove Actor"
+    bl_options = {"REGISTER", "UNDO"}
+    actor: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.remove_actor(tool.Ifc, actor=tool.Ifc.get().by_id(self.actor))
@@ -18,7 +18,7 @@

 import bpy
 from blenderbim.bim.prop import StrProperty, Attribute
-from blenderbim.bim.module.owner.data import OwnerData
+from blenderbim.bim.module.owner.data import OwnerData, ActorData
 from bpy.types import PropertyGroup
 from bpy.props import (
    PointerProperty,
@@ -44,6 +44,20 @@ def get_user_organisation(self, context):
    return OwnerData.data["user_organisation"]


+def get_actor(self, context):
+    if not ActorData.is_loaded:
+        ActorData.load()
+    return ActorData.data["actor"]
+
+
+def update_actor_type(self, context):
+    ActorData.data["actor"] = ActorData.actor()
+
+
+def update_actor_class(self, context):
+    ActorData.data["actors"] = ActorData.actors()
+
+
 class BIMOwnerProperties(PropertyGroup):
    active_person_id: IntProperty(name="Active Person Id")
    person_attributes: CollectionProperty(name="Person Attributes", type=Attribute)
@@ -64,3 +78,20 @@ class BIMOwnerProperties(PropertyGroup):
    user_person: EnumProperty(items=get_user_person, name="Person")
    user_organisation: EnumProperty(items=get_user_organisation, name="Organisation")
    active_user_id: IntProperty(name="Active User Id")
+    active_actor_id: IntProperty(name="Active Actor Id")
+    actor_attributes: CollectionProperty(name="Actor Attributes", type=Attribute)
+    actor_class: EnumProperty(
+        items=(("IfcActor", "Actor", ""), ("IfcOccupant", "Occupant", "")),
+        name="Actor Type",
+        update=update_actor_class,
+    )
+    actor_type: EnumProperty(
+        items=(
+            ("IfcPerson", "Person", ""),
+            ("IfcOrganization", "Organisation", ""),
+            ("IfcPersonAndOrganization", "User", ""),
+        ),
+        name="Actor Type",
+        update=update_actor_type,
+    )
+    actor: EnumProperty(items=get_actor, name="Actor")
@@ -19,7 +19,7 @@
 import bpy
 import blenderbim.bim.helper
 import blenderbim.tool as tool
-from blenderbim.bim.module.owner.data import PeopleData, OrganisationsData, OwnerData
+from blenderbim.bim.module.owner.data import PeopleData, OrganisationsData, OwnerData, ActorData


 def draw_roles(box, parent):
@@ -227,3 +227,52 @@ class BIM_PT_owner(bpy.types.Panel):
                row.operator("bim.set_user", icon="KEYFRAME_HLT", text="").user = user["id"]
            op = row.operator("bim.remove_person_and_organisation", icon="X", text="")
            op.person_and_organisation = user["id"]
+
+
+class BIM_PT_actor(bpy.types.Panel):
+    bl_label = "IFC Actor"
+    bl_idname = "BIM_PT_actor"
+    bl_options = {"DEFAULT_CLOSED"}
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+    bl_context = "scene"
+    bl_parent_id = "BIM_PT_project_setup"
+
+    @classmethod
+    def poll(cls, context):
+        return tool.Ifc.get()
+
+    def draw(self, context):
+        if not ActorData.is_loaded:
+            ActorData.load()
+
+        self.props = context.scene.BIMOwnerProperties
+
+        self.layout.use_property_split = True
+        self.layout.use_property_decorate = False
+
+        row = self.layout.row(align=True)
+        row.prop(self.props, "actor_class", text="")
+        row.prop(self.props, "actor_type", text="")
+        if ActorData.data["actor"]:
+            row = self.layout.row(align=True)
+            row.prop(self.props, "actor", text="")
+            row.operator("bim.add_actor", icon="ADD", text="")
+        else:
+            self.layout.label(text="No users found.")
+
+        for actor in ActorData.data["actors"]:
+            self.draw_actor(actor)
+
+    def draw_actor(self, actor):
+        if actor["is_editing"]:
+            box = self.layout.box()
+            row = box.row(align=True)
+            row.operator("bim.edit_actor", icon="CHECKMARK")
+            row.operator("bim.disable_editing_actor", icon="CANCEL", text="")
+            blenderbim.bim.helper.draw_attributes(self.props.actor_attributes, box)
+        else:
+            row = self.layout.row(align=True)
+            row.label(text=actor["name"])
+            row.operator("bim.enable_editing_actor", icon="GREASEPENCIL", text="").actor = actor["id"]
+            row.operator("bim.remove_actor", icon="X", text="").actor = actor["id"]
@@ -28,6 +28,7 @@ classes = (
    operator.UnlinkIfc,
    operator.UnloadLink,
    operator.LoadLink,
+    operator.ToggleLinkVisibility,
    operator.SelectLibraryFile,
    operator.ChangeLibraryElement,
    operator.RefreshLibrary,
@@ -16,6 +16,7 @@
 # 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 blenderbim.tool as tool
 from blenderbim.bim.ifc import IfcStore
@@ -31,9 +32,32 @@ class ProjectData:

    @classmethod
    def load(cls):
-        cls.data = {"export_schema": cls.get_export_schema()}
+        cls.data = {
+            "export_schema": cls.get_export_schema(),
+            "template_file": cls.template_file(),
+            "last_saved": cls.last_saved(),
+        }
        cls.is_loaded = True

    @classmethod
    def get_export_schema(cls):
        return [(s, s, "") for s in IfcStore.schema_identifiers]
+
+    @classmethod
+    def template_file(cls):
+        files = os.listdir(os.path.join(bpy.context.scene.BIMProperties.data_dir, "libraries"))
+        results = [("0", "Blank Project", "")]
+        results.extend([(f, f.replace(".ifc", ""), "") for f in files if ".ifc" in f])
+        return results
+
+    @classmethod
+    def last_saved(cls):
+        ifc = tool.Ifc.get()
+        if not ifc:
+            return ""
+        try:
+            save_datetime = ifc.wrapped_data.header.file_name.time_stamp
+            save_date, save_time = save_datetime.split("T")
+            return f"{save_date} {':'.join(save_time.split(':')[0:2])}"
+        except:
+            return ""
@@ -27,6 +27,7 @@ import ifcopenshell.util.selector
 import ifcopenshell.util.representation
 import blenderbim.bim.handler
 import blenderbim.tool as tool
+import blenderbim.core.project as core
 import blenderbim.core.context
 import blenderbim.core.owner
 from blenderbim.bim.ifc import IfcStore
@@ -45,80 +46,16 @@ class CreateProject(bpy.types.Operator):
    def execute(self, context):
        IfcStore.begin_transaction(self)
        IfcStore.add_transaction_operation(self, rollback=self.rollback, commit=lambda data: True)
-        result = self._execute(context)
-        self.transaction_data = {"file": self.file}
+        self._execute(context)
+        self.transaction_data = {"file": tool.Ifc.get()}
        IfcStore.add_transaction_operation(self, rollback=lambda data: True, commit=self.commit)
        IfcStore.end_transaction(self)
-        return result
-
-    def _execute(self, context):
-        active_object = context.view_layer.objects.active
-        self.file = IfcStore.get_file()
-        if self.file:
-            return {"FINISHED"}
-
-        IfcStore.file = ifcopenshell.api.run(
-            "project.create_file", **{"version": context.scene.BIMProjectProperties.export_schema}
-        )
-        self.file = IfcStore.get_file()
-
-        if self.file.schema == "IFC2X3":
-            person = blenderbim.core.owner.add_person(tool.Ifc)
-            organisation = blenderbim.core.owner.add_organisation(tool.Ifc)
-            user = blenderbim.core.owner.add_person_and_organisation(tool.Ifc, person=person, organisation=organisation)
-            blenderbim.core.owner.set_user(tool.Owner, user=user)
-
-        project = bpy.data.objects.new(self.get_name("IfcProject", "My Project"), None)
-        site = bpy.data.objects.new(self.get_name("IfcSite", "My Site"), None)
-        building = bpy.data.objects.new(self.get_name("IfcBuilding", "My Building"), None)
-        building_storey = bpy.data.objects.new(self.get_name("IfcBuildingStorey", "My Storey"), None)
-
-        bpy.ops.bim.assign_class(obj=project.name, ifc_class="IfcProject")
-        blenderbim.core.unit.assign_scene_units(tool.Ifc, tool.Unit)
-
-        model = blenderbim.core.context.add_context(
-            tool.Ifc, context_type="Model", context_identifier="", target_view="", parent=0
-        )
-        body_context = blenderbim.core.context.add_context(
-            tool.Ifc, context_type="Model", context_identifier="Body", target_view="MODEL_VIEW", parent=model
-        )
-        blenderbim.core.context.add_context(
-            tool.Ifc, context_type="Model", context_identifier="Box", target_view="MODEL_VIEW", parent=model
-        )
-        plan = blenderbim.core.context.add_context(
-            tool.Ifc, context_type="Plan", context_identifier="", target_view="", parent=0
-        )
-        blenderbim.core.context.add_context(
-            tool.Ifc, context_type="Plan", context_identifier="Annotation", target_view="PLAN_VIEW", parent=plan
-        )
-
-        blenderbim.bim.handler.refresh_ui_data()
-        context.scene.BIMRootProperties.contexts = str(body_context.id())
-
-        bpy.ops.bim.assign_class(obj=site.name, ifc_class="IfcSite")
-        bpy.ops.bim.assign_class(obj=building.name, ifc_class="IfcBuilding")
-        bpy.ops.bim.assign_class(obj=building_storey.name, ifc_class="IfcBuildingStorey")
-
-        blenderbim.core.aggregate.assign_object(
-            tool.Ifc, tool.Aggregate, tool.Collector, relating_obj=project, related_obj=site
-        )
-        blenderbim.core.aggregate.assign_object(
-            tool.Ifc, tool.Aggregate, tool.Collector, relating_obj=site, related_obj=building
-        )
-        blenderbim.core.aggregate.assign_object(
-            tool.Ifc, tool.Aggregate, tool.Collector, relating_obj=building, related_obj=building_storey
-        )
-
-        context.view_layer.objects.active = active_object
        return {"FINISHED"}

-    def get_name(self, ifc_class, name):
-        if not bpy.data.objects.get(f"{ifc_class}/{name}"):
-            return name
-        i = 2
-        while bpy.data.objects.get(f"{ifc_class}/{name} {i}"):
-            i += 1
-        return f"{name} {i}"
+    def _execute(self, context):
+        props = context.scene.BIMProjectProperties
+        template = None if props.template_file == "0" else props.template_file
+        core.create_project(tool.Ifc, tool.Project, schema=props.export_schema, template=template)

    def rollback(self, data):
        IfcStore.file = None
@@ -373,7 +310,11 @@ class AppendLibraryElement(bpy.types.Operator):
            self.import_type_from_ifc(element, context)
        elif element.is_a("IfcMaterial"):
            self.import_material_from_ifc(element, context)
-        context.scene.BIMProjectProperties.library_elements[self.prop_index].is_appended = True
+        try:
+            context.scene.BIMProjectProperties.library_elements[self.prop_index].is_appended = True
+        except:
+            # TODO Remove this terrible code when I refactor this into the core
+            pass
        blenderbim.bim.handler.purge_module_data()
        return {"FINISHED"}

@@ -670,10 +611,14 @@ class LinkIfc(bpy.types.Operator):
    bl_description = "Link a Blender file"
    filepath: bpy.props.StringProperty(subtype="FILE_PATH")
    filter_glob: bpy.props.StringProperty(default="*.blend;*.blend1", options={"HIDDEN"})
+    use_relative_path: bpy.props.BoolProperty(name="Use Relative Path", default=False)

    def execute(self, context):
        new = context.scene.BIMProjectProperties.links.add()
-        new.name = self.filepath
+        filepath = self.filepath
+        if self.use_relative_path:
+            filepath = os.path.relpath(filepath, bpy.path.abspath("//"))
+        new.name = filepath
        bpy.ops.bim.load_link(filepath=self.filepath)
        return {"FINISHED"}

@@ -705,13 +650,16 @@ class UnloadLink(bpy.types.Operator):
    filepath: bpy.props.StringProperty()

    def execute(self, context):
+        filepath = self.filepath
+        if not os.path.isabs(filepath):
+            filepath = os.path.abspath(os.path.join(bpy.path.abspath("//"), filepath))
        for collection in context.scene.collection.children:
-            if collection.library and collection.library.filepath == self.filepath:
+            if collection.library and collection.library.filepath == filepath:
                context.scene.collection.children.unlink(collection)
        for scene in bpy.data.scenes:
-            if scene.library and scene.library.filepath == self.filepath:
+            if scene.library and scene.library.filepath == filepath:
                bpy.data.scenes.remove(scene)
-        link = context.scene.BIMProjectProperties.links.get(self.filepath)
+        link = context.scene.BIMProjectProperties.links.get(filepath)
        link.is_loaded = False
        return {"FINISHED"}

@@ -724,20 +672,44 @@ class LoadLink(bpy.types.Operator):
    filepath: bpy.props.StringProperty()

    def execute(self, context):
+        filepath = self.filepath
+        if not os.path.isabs(filepath):
+            filepath = os.path.abspath(os.path.join(bpy.path.abspath("//"), filepath))
        with bpy.data.libraries.load(self.filepath, link=True) as (data_from, data_to):
            data_to.scenes = data_from.scenes
        for scene in bpy.data.scenes:
-            if not scene.library or scene.library.filepath != self.filepath:
+            if not scene.library or scene.library.filepath != filepath:
                continue
            for child in scene.collection.children:
                if "IfcProject" not in child.name:
                    continue
                bpy.data.scenes[0].collection.children.link(child)
-        link = context.scene.BIMProjectProperties.links.get(self.filepath)
+        link = context.scene.BIMProjectProperties.links.get(filepath)
+        link.collection_name = child.name
        link.is_loaded = True
        return {"FINISHED"}


+class ToggleLinkVisibility(bpy.types.Operator):
+    bl_idname = "bim.toggle_link_visibility"
+    bl_label = "Toggle Link Visibility"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Toggle visibility between SOLID and WIREFRAME"
+    collection_name: bpy.props.StringProperty()
+
+    def execute(self, context):
+        collection_name = self.collection_name
+        objs = filter(lambda obj: "IfcOpeningElement" not in obj.name, bpy.data.collections[collection_name].all_objects)
+        for i,obj in enumerate(objs):
+            if i == 0:
+                if obj.display_type == "WIRE":
+                    display_type = "TEXTURED"
+                else:
+                    display_type = "WIRE"
+            obj.display_type = display_type
+        return {"FINISHED"}
+
+
 class ExportIFC(bpy.types.Operator):
    bl_idname = "export_ifc.bim"
    bl_label = "Export IFC"
@@ -38,6 +38,12 @@ def get_export_schema(self, context):
    return ProjectData.data["export_schema"]


+def get_template_file(self, context):
+    if not ProjectData.is_loaded:
+        ProjectData.load()
+    return ProjectData.data["template_file"]
+
+
 def update_filter_mode(self, context):
    self.filter_categories.clear()
    if self.filter_mode == "NONE":
@@ -79,6 +85,7 @@ class FilterCategory(PropertyGroup):

 class Link(PropertyGroup):
    name: StringProperty(name="Name")
+    collection_name: StringProperty(name="Collection Name")
    is_loaded: BoolProperty(name="Is Loaded", default=False)


@@ -132,6 +139,7 @@ class BIMProjectProperties(PropertyGroup):
    links: CollectionProperty(name="Links", type=Link)
    active_link_index: IntProperty(name="Active Link Index")
    export_schema: EnumProperty(items=get_export_schema, name="IFC Schema")
+    template_file: EnumProperty(items=get_template_file, name="Template File")

    def get_library_element_index(self, lib_element):
        return next((i for i in range(len(self.library_elements)) if self.library_elements[i] == lib_element))
@@ -28,7 +28,7 @@ class BIM_PT_project(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
-    bl_parent_id = "BIM_PT_project_setup"
+    bl_parent_id = "BIM_PT_project_info"

    def draw(self, context):
        if not ProjectData.is_loaded:
@@ -94,8 +94,7 @@ class BIM_PT_project(Panel):
        props = context.scene.BIMProperties
        pprops = context.scene.BIMProjectProperties
        row = self.layout.row(align=True)
-        row.label(text="IFC Filename", icon="FILE")
-        row.label(text=os.path.basename(props.ifc_file) or "No File Found")
+        row.label(text=os.path.basename(props.ifc_file) or "No File Found", icon="FILE")

        if IfcStore.get_file():
            row.prop(pprops, "is_authoring", icon="MODIFIER", text="")
@@ -136,20 +135,21 @@ class BIM_PT_project(Panel):
            row = self.layout.row(align=True)
            row.label(text="File Not Loaded", icon="ERROR")

+        if props.ifc_file:
+            row = self.layout.row(align=True)
+            row.label(text="Saved", icon="EXPORT")
+            row.label(text=ProjectData.data["last_saved"])
+
+            row = self.layout.row(align=True)
+            row.prop(props, "ifc_file", text="")
+            row.operator("bim.reload_ifc_file", icon="FILE_REFRESH", text="")
+            row.operator("bim.select_ifc_file", icon="FILE_FOLDER", text="")
+
        row = self.layout.row(align=True)
-        row.prop(props, "ifc_file", text="")
-        row.operator("bim.reload_ifc_file", icon="FILE_REFRESH", text="")
-        op = row.operator("export_ifc.bim", icon="FILE_TICK", text="")
+        op = row.operator("export_ifc.bim", icon="EXPORT", text="Save Project")
+        op.should_save_as = False
+        op = row.operator("export_ifc.bim", icon="FILE_TICK", text="Save As")
        op.should_save_as = True
-        row.operator("bim.select_ifc_file", icon="FILE_FOLDER", text="")
-
-        row = self.layout.row(align=True)
-        row.prop(props, "schema_dir")
-        row.operator("bim.select_schema_dir", icon="FILE_FOLDER", text="")
-
-        row = self.layout.row(align=True)
-        row.prop(props, "data_dir")
-        row.operator("bim.select_data_dir", icon="FILE_FOLDER", text="")

    def draw_create_project_ui(self, context):
        props = context.scene.BIMProperties
@@ -164,6 +164,9 @@ class BIM_PT_project(Panel):
        row.prop(props, "area_unit", text="Area Unit")
        row = self.layout.row()
        row.prop(props, "volume_unit", text="Volume Unit")
+        row = self.layout.row()
+        row.prop(pprops, "template_file", text="Template")
+
        row = self.layout.row(align=True)
        row.operator("bim.create_project")
        row.operator("bim.load_project")
@@ -281,11 +284,14 @@ class BIM_UL_links(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.name)
            if item.is_loaded:
+                row.label(text=item.name)
+                op = row.operator("bim.toggle_link_visibility", text="", icon="HIDE_OFF")
+                op.collection_name = item.collection_name
                op = row.operator("bim.unload_link", text="", icon="UNLINKED")
                op.filepath = item.name
            else:
+                row.prop(item, "name", text="")
                op = row.operator("bim.load_link", text="", icon="LINKED")
                op.filepath = item.name
                op = row.operator("bim.unlink_ifc", text="", icon="X")
@@ -20,13 +20,12 @@ import bpy
 from . import ui, prop, operator

 classes = (
-    operator.EnableReassignClass,
-    operator.DisableReassignClass,
-    operator.ReassignClass,
    operator.AssignClass,
-    operator.UnassignClass,
-    operator.UnlinkObject,
    operator.CopyClass,
+    operator.DisableReassignClass,
+    operator.EnableReassignClass,
+    operator.ReassignClass,
+    operator.UnlinkObject,
    prop.BIMRootProperties,
    ui.BIM_PT_class,
 )
@@ -32,12 +32,47 @@ class IfcClassData:
    @classmethod
    def load(cls):
        cls.is_loaded = True
-        cls.data = {
-            "contexts": cls.contexts(),
-            "has_entity": cls.has_entity(),
-            "name": cls.name(),
-            "ifc_class": cls.ifc_class(),
-        }
+        cls.data = {}
+        cls.data["ifc_products"] = cls.ifc_products()
+        cls.data["ifc_classes"] = cls.ifc_classes()
+        cls.data["contexts"] = cls.contexts()
+        cls.data["has_entity"] = cls.has_entity()
+        cls.data["name"] = cls.name()
+        cls.data["ifc_class"] = cls.ifc_class()
+
+    @classmethod
+    def ifc_products(cls):
+        products = [
+            "IfcElement",
+            "IfcElementType",
+            "IfcSpatialElement",
+            "IfcGroup",
+            "IfcStructuralItem",
+            "IfcContext",
+            "IfcAnnotation",
+            "IfcRelSpaceBoundary",
+        ]
+        if tool.Ifc.get_schema() == "IFC2X3":
+            products = [
+                "IfcElement",
+                "IfcElementType",
+                "IfcSpatialStructureElement",
+                "IfcGroup",
+                "IfcStructuralItem",
+                "IfcAnnotation",
+                "IfcRelSpaceBoundary",
+            ]
+        return [(e, e, "") for e in products]
+
+    @classmethod
+    def ifc_classes(cls):
+        ifc_product = bpy.context.scene.BIMRootProperties.ifc_product
+        declaration = tool.Ifc.schema().declaration_by_name(ifc_product)
+        declarations = ifcopenshell.util.schema.get_subtypes(declaration)
+        names = [d.name() for d in declarations]
+        if ifc_product == "IfcElementType":
+            names.extend(("IfcDoorStyle", "IfcWindowStyle"))
+        return [(c, c, "") for c in sorted(names)]

    @classmethod
    def contexts(cls):
@@ -113,7 +113,7 @@ class ReassignClass(bpy.types.Operator):
        return {"FINISHED"}


-class AssignClass(bpy.types.Operator):
+class AssignClass(bpy.types.Operator, Operator):
    bl_idname = "bim.assign_class"
    bl_label = "Assign IFC Class"
    bl_options = {"REGISTER", "UNDO"}
@@ -126,178 +126,29 @@ class AssignClass(bpy.types.Operator):
    should_add_representation: bpy.props.BoolProperty(default=True)
    ifc_representation_class: bpy.props.StringProperty()

-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
    def _execute(self, context):
        objects = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
-        self.file = IfcStore.get_file()
-        if not self.ifc_class:
-            self.ifc_class = context.scene.BIMRootProperties.ifc_class
-        self.declaration = IfcStore.get_schema().declaration_by_name(self.ifc_class)
-        if self.predefined_type == "USERDEFINED":
-            self.predefined_type = self.userdefined_type
+        ifc_class = self.ifc_class or context.scene.BIMRootProperties.ifc_class
+        predefined_type = self.userdefined_type if self.predefined_type == "USERDEFINED" else self.predefined_type
+        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)
+        active_object = context.active_object
        for obj in objects:
-            self.assign_class(context, obj)
-        return {"FINISHED"}
-
-    def assign_class(self, context, obj):
-        if obj.BIMObjectProperties.ifc_definition_id:
-            return
-        product = ifcopenshell.api.run(
-            "root.create_entity",
-            self.file,
-            **{
-                "ifc_class": self.ifc_class,
-                "predefined_type": self.predefined_type or None,
-                "name": obj.name,
-            },
-        )
-        obj.name = "{}/{}".format(product.is_a(), obj.name)
-        IfcStore.link_element(product, obj)
-
-        if self.should_add_representation:
-            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)
-            blenderbim.core.geometry.add_representation(
+            core.assign_class(
                tool.Ifc,
-                tool.Geometry,
-                tool.Style,
-                tool.Surveyor,
+                tool.Collector,
+                tool.Root,
                obj=obj,
+                ifc_class=ifc_class,
+                predefined_type=predefined_type,
+                should_add_representation=self.should_add_representation,
                context=ifc_context,
                ifc_representation_class=self.ifc_representation_class,
-                profile_set_usage=None,
            )
-
-        if product.is_a("IfcElementType"):
-            tool.Collector.assign(obj)
-        elif product.is_a("IfcOpeningElement"):
-            obj.display_type = "WIRE"
-            tool.Collector.assign(obj)
-        elif (
-            product.is_a("IfcSpatialElement")
-            or product.is_a("IfcSpatialStructureElement")
-            or product.is_a("IfcProject")
-            or product.is_a("IfcContext")
-        ):
-            self.place_in_spatial_collection(obj, context)
-        elif product.is_a("IfcStructuralItem"):
-            if product.is_a("IfcStructuralMember"):
-                self.place_in_structural_items_collection(obj, context, structural_collection="Members")
-            elif product.is_a("IfcStructuralConnection"):
-                self.place_in_structural_items_collection(obj, context, structural_collection="Connections")
-        else:
-            self.assign_potential_spatial_container(obj)
-        context.view_layer.objects.active = obj
-
-    def place_in_spatial_collection(self, obj, context):
-        for collection in obj.users_collection:
-            if collection.name == obj.name:
-                return
-        parent_collection = None
-        for collection in obj.users_collection:
-            collection.objects.unlink(obj)
-            if "Ifc" in collection.name:
-                parent_collection = collection
-        collection = bpy.data.collections.new(obj.name)
-        collection.objects.link(obj)
-        if parent_collection:
-            parent_collection.children.link(collection)
-            blenderbim.core.aggregate.assign_object(
-                tool.Ifc,
-                tool.Aggregate,
-                tool.Collector,
-                relating_obj=bpy.data.objects.get(parent_collection.name),
-                related_obj=obj,
-            )
-        else:
-            context.scene.collection.children.link(collection)
-
-    def place_in_structural_items_collection(self, obj, context, structural_collection):
-        for project in [c for c in context.view_layer.layer_collection.children if "IfcProject" in c.name]:
-            if not [c for c in project.children if "StructuralItems" in c.name]:
-                members = bpy.data.collections.new("Members")
-                connections = bpy.data.collections.new("Connections")
-                items = bpy.data.collections.new("StructuralItems")
-                items.children.link(members)
-                items.children.link(connections)
-                project.collection.children.link(items)
-
-            for coll in [c for c in project.children if "StructuralItems" in c.name]:
-                for collection in [c for c in coll.children if structural_collection in c.name]:
-                    for user_collection in obj.users_collection:
-                        user_collection.objects.unlink(obj)
-                    collection.collection.objects.link(obj)
-                    break
-                break
-            break
-
-    def assign_potential_spatial_container(self, obj):
-        for collection in obj.users_collection:
-            if "Ifc" not in collection.name or collection.name == obj.name:
-                continue
-            spatial_obj = bpy.data.objects.get(collection.name)
-            if spatial_obj and spatial_obj.BIMObjectProperties.ifc_definition_id:
-                element = self.file.by_id(spatial_obj.BIMObjectProperties.ifc_definition_id)
-                if self.file.schema != "IFC2X3" and not element.is_a("IfcSpatialElement"):
-                    continue
-                elif self.file.schema == "IFC2X3" and not element.is_a("IfcSpatialStructureElement"):
-                    continue
-                blenderbim.core.spatial.assign_container(
-                    tool.Ifc,
-                    tool.Collector,
-                    tool.Spatial,
-                    structure_obj=spatial_obj,
-                    element_obj=obj,
-                )
-                break
-
-
-class UnassignClass(bpy.types.Operator):
-    bl_idname = "bim.unassign_class"
-    bl_label = "Unassign IFC Class"
-    bl_options = {"REGISTER", "UNDO"}
-    obj: bpy.props.StringProperty()
-
-    def execute(self, context):
-        return IfcStore.execute_ifc_operator(self, context)
-
-    def _execute(self, context):
-        self.file = IfcStore.get_file()
-        if self.obj:
-            objects = [bpy.data.objects.get(self.obj)]
-        else:
-            objects = context.selected_objects
-        for obj in objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
-                continue
-            product = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
-            self.remove_voids(product, obj)
-            IfcStore.unlink_element(product, obj)
-            if product.is_a("IfcGridAxis"):
-                ifcopenshell.api.run("grid.remove_grid_axis", self.file, **{"axis": product})
-            elif product.is_a("IfcGrid"):
-                grid_collection = bpy.data.collections.get(obj.name)
-                for axis_collection in grid_collection.children:
-                    for axis_obj in axis_collection.objects:
-                        bpy.ops.bim.unassign_class(obj=axis_obj.name)
-            else:
-                ifcopenshell.api.run("root.remove_product", self.file, **{"product": product})
-            if "/" in obj.name and obj.name[0:3] == "Ifc":
-                obj.name = "/".join(obj.name.split("/")[1:])
-            if obj.data and obj.data.name == "Void":
-                bpy.data.objects.remove(obj)
-        return {"FINISHED"}
-
-    def remove_voids(self, product, obj):
-        if product.id() not in VoidData.products:
-            VoidData.load(self.file, product.id())
-        for opening_id in VoidData.products[product.id()]:
-            bpy.ops.bim.remove_opening(opening_id=opening_id, obj=obj.name)
+        context.view_layer.objects.active = active_object


 class UnlinkObject(bpy.types.Operator):
@@ -33,17 +33,11 @@ from bpy.props import (
    CollectionProperty,
 )

-products_enum = []
-classes_enum = []
 types_enum = []


 def purge():
-    global products_enum
-    global classes_enum
    global types_enum
-    products_enum = []
-    classes_enum = []
    types_enum = []


@@ -61,10 +55,9 @@ def getIfcPredefinedTypes(self, context):
    return types_enum


-def refreshClasses(self, context):
-    global classes_enum
-    classes_enum.clear()
-    enum = getIfcClasses(self, context)
+def refresh_classes(self, context):
+    IfcClassData.load()
+    enum = get_ifc_classes(self, context)
    context.scene.BIMRootProperties.ifc_class = enum[0][0]


@@ -76,38 +69,16 @@ def refreshPredefinedTypes(self, context):
        context.scene.BIMRootProperties.ifc_predefined_type = enum[0][0]


-def getIfcProducts(self, context):
-    global products_enum
-    file = IfcStore.get_file()
-    if len(products_enum) < 1:
-        products_enum.extend(
-            [
-                (e, e, "")
-                for e in [
-                    "IfcElement",
-                    "IfcElementType",
-                    "IfcSpatialElement",
-                    "IfcGroup",
-                    "IfcStructuralItem",
-                    "IfcContext",
-                    "IfcAnnotation",
-                    "IfcRelSpaceBoundary",
-                ]
-            ]
-        )
-        if file.schema == "IFC2X3":
-            products_enum[2] = ("IfcSpatialStructureElement", "IfcSpatialStructureElement", "")
-    return products_enum
+def get_ifc_products(self, context):
+    if not IfcClassData.is_loaded:
+        IfcClassData.load()
+    return IfcClassData.data["ifc_products"]


-def getIfcClasses(self, context):
-    global classes_enum
-    file = IfcStore.get_file()
-    if len(classes_enum) < 1 and file:
-        declaration = IfcStore.get_schema().declaration_by_name(context.scene.BIMRootProperties.ifc_product)
-        declarations = ifcopenshell.util.schema.get_subtypes(declaration)
-        classes_enum.extend([(c, c, "") for c in sorted([d.name() for d in declarations])])
-    return classes_enum
+def get_ifc_classes(self, context):
+    if not IfcClassData.is_loaded:
+        IfcClassData.load()
+    return IfcClassData.data["ifc_classes"]


 def get_contexts(self, context):
@@ -118,7 +89,7 @@ def get_contexts(self, context):

 class BIMRootProperties(PropertyGroup):
    contexts: EnumProperty(items=get_contexts, name="Contexts")
-    ifc_product: EnumProperty(items=getIfcProducts, name="Products", update=refreshClasses)
-    ifc_class: EnumProperty(items=getIfcClasses, name="Class", update=refreshPredefinedTypes)
+    ifc_product: EnumProperty(items=get_ifc_products, name="Products", update=refresh_classes)
+    ifc_class: EnumProperty(items=get_ifc_classes, name="Class", update=refreshPredefinedTypes)
    ifc_predefined_type: EnumProperty(items=getIfcPredefinedTypes, name="Predefined Type", default=None)
    ifc_userdefined_type: StringProperty(name="Userdefined Type")
@@ -65,10 +65,6 @@ class BIM_PT_class(Panel):
                row.operator("bim.unlink_object", icon="UNLINKED", text="")
                if IfcStore.get_file().by_id(props.ifc_definition_id).is_a("IfcRoot"):
                    row.operator("bim.enable_reassign_class", icon="GREASEPENCIL", text="")
-                if context.selected_objects:
-                    row.operator("bim.unassign_class", icon="X", text="")
-                else:
-                    row.operator("bim.unassign_class", icon="X", text="").obj = context.active_object.name
        else:
            ifc_predefined_types = root_prop.getIfcPredefinedTypes(context.scene.BIMRootProperties, context)
            self.draw_class_dropdowns(context, ifc_predefined_types)
@@ -28,7 +28,7 @@ class BIM_PT_search(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "scene"
-    bl_parent_id = "BIM_PT_utilities"
+    bl_parent_id = "BIM_PT_collaboration"

    @classmethod
    def poll(cls, context):
@@ -71,6 +71,7 @@ classes = (
    operator.EnableEditingWorkSchedule,
    operator.EnableEditingWorkTime,
    operator.ExpandTask,
+    operator.ExportMSP,
    operator.ExportP6,
    operator.GenerateGanttChart,
    operator.ImportMSP,
@@ -127,6 +128,7 @@ classes = (

 def menu_func_export(self, context):
    self.layout.operator(operator.ExportP6.bl_idname, text="P6 (.xml)")
+    self.layout.operator(operator.ExportMSP.bl_idname, text="Microsoft Project (.xml)")


 def menu_func_import(self, context):
@@ -39,6 +39,19 @@ from ifcopenshell.api.sequence.data import Data
 from ifcopenshell.api.resource.data import Data as ResourceData


+def animate_text(scene, context):
+    data = bpy.data.curves.get("Timeline")
+    if not data or not bpy.data.objects.get("Timeline"):
+        self.remove_text_animation_handler()
+        scene.frame_current
+    props = data.BIMDateTextProperties
+    start = parser.parse(props.start, dayfirst=True, fuzzy=True)
+    finish = parser.parse(props.finish, dayfirst=True, fuzzy=True)
+    duration = finish - start
+    frame_date = (((scene.frame_current - props.start_frame) / props.total_frames) * duration) + start
+    data.body = frame_date.date().isoformat()
+
+
 class AddWorkPlan(bpy.types.Operator):
    bl_idname = "bim.add_work_plan"
    bl_label = "Add Work Plan"
@@ -976,6 +989,7 @@ class GenerateGanttChart(bpy.types.Operator):
        data = {
            "pID": task.id(),
            "pName": task.Name,
+            "pCaption": task.Name,
            "pStart": task.TaskTime.ScheduleStart if task.TaskTime else "",
            "pEnd": task.TaskTime.ScheduleFinish if task.TaskTime else "",
            "pPlanStart": task.TaskTime.ScheduleStart if task.TaskTime else "",
@@ -986,6 +1000,7 @@ class GenerateGanttChart(bpy.types.Operator):
            "pParent": task.Nests[0].RelatingObject.id() if task.Nests else 0,
            "pOpen": 1,
            "pCost": 1,
+            "ifcduration": task.TaskTime.ScheduleDuration if task.TaskTime else "",
        }
        if task.TaskTime and task.TaskTime.IsCritical:
            data["pClass"] = "gtaskred"
@@ -1196,12 +1211,44 @@ class ImportMSP(bpy.types.Operator, ImportHelper):
        return {"FINISHED"}


+class ExportMSP(bpy.types.Operator, ImportHelper):
+    bl_idname = "export_msp.bim"
+    bl_label = "Export MSP"
+    bl_options = {"REGISTER", "UNDO"}
+    filename_ext = ".xml"
+    filter_glob: bpy.props.StringProperty(default="*.xml", options={"HIDDEN"})
+    holiday_start_date: bpy.props.StringProperty(default="2022-01-01", name="Holiday Start Date")
+    holiday_finish_date: bpy.props.StringProperty(default="2023-01-01", name="Holiday Finish Date")
+
+    @classmethod
+    def poll(cls, context):
+        ifc_file = IfcStore.get_file()
+        return ifc_file is not None
+
+    def execute(self, context):
+        from ifc4d.ifc2msp import Ifc2Msp
+
+        self.file = IfcStore.get_file()
+        start = time.time()
+        ifc2msp = Ifc2Msp()
+        ifc2msp.work_schedule = self.file.by_type("IfcWorkSchedule")[0]
+        ifc2msp.xml = bpy.path.ensure_ext(self.filepath, ".xml")
+        ifc2msp.file = self.file
+        ifc2msp.holiday_start_date = parser.parse(self.holiday_start_date).date()
+        ifc2msp.holiday_finish_date = parser.parse(self.holiday_finish_date).date()
+        ifc2msp.execute()
+        print("Export finished in {:.2f} seconds".format(time.time() - start))
+        return {"FINISHED"}
+
+
 class ExportP6(bpy.types.Operator, ImportHelper):
    bl_idname = "export_p6.bim"
    bl_label = "Export P6"
    bl_options = {"REGISTER", "UNDO"}
    filename_ext = ".xml"
    filter_glob: bpy.props.StringProperty(default="*.xml", options={"HIDDEN"})
+    holiday_start_date: bpy.props.StringProperty(default="2022-01-01", name="Holiday Start Date")
+    holiday_finish_date: bpy.props.StringProperty(default="2023-01-01", name="Holiday Finish Date")

    @classmethod
    def poll(cls, context):
@@ -1214,10 +1261,12 @@ class ExportP6(bpy.types.Operator, ImportHelper):
        self.file = IfcStore.get_file()
        start = time.time()
        ifc2p6 = Ifc2P6()
-        ifc2p6.xml = self.filepath
+        ifc2p6.xml = bpy.path.ensure_ext(self.filepath, ".xml")
        ifc2p6.file = self.file
+        ifc2p6.holiday_start_date = parser.parse(self.holiday_start_date).date()
+        ifc2p6.holiday_finish_date = parser.parse(self.holiday_finish_date).date()
        ifc2p6.execute()
-        print("Import finished in {:.2f} seconds".format(time.time() - start))
+        print("Export finished in {:.2f} seconds".format(time.time() - start))
        return {"FINISHED"}


@@ -1632,6 +1681,10 @@ class EnableEditingSequenceTimeLag(bpy.types.Operator):

    def import_attributes(self, name, prop, data):
        if name == "LagValue":
+            prop = self.props.time_lag_attributes.add()
+            prop.name = name
+            prop.is_null = data[name] is None
+            prop.is_optional = False
            if isinstance(data[name], isodate.Duration):
                prop.data_type = "string"
                prop.string_value = (
@@ -1866,22 +1919,10 @@ class VisualiseWorkScheduleDateRange(bpy.types.Operator):
        obj.data.BIMDateTextProperties.total_frames = int(self.total_frames)
        obj.data.BIMDateTextProperties.start = self.props.visualisation_start
        obj.data.BIMDateTextProperties.finish = self.props.visualisation_finish
-        bpy.app.handlers.frame_change_post.append(self.animate_text)
+        bpy.app.handlers.frame_change_post.append(animate_text)

    def remove_text_animation_handler(self):
-        bpy.app.handlers.frame_change_post.remove(self.animate_text)
-
-    def animate_text(self, scene, context):
-        data = bpy.data.curves.get("Timeline")
-        if not data or not bpy.data.objects.get("Timeline"):
-            self.remove_text_animation_handler()
-            scene.frame_current
-        props = data.BIMDateTextProperties
-        start = parser.parse(props.start, dayfirst=True, fuzzy=True)
-        finish = parser.parse(props.finish, dayfirst=True, fuzzy=True)
-        duration = finish - start
-        frame_date = (((scene.frame_current - props.start_frame) / props.total_frames) * duration) + start
-        data.body = frame_date.date().isoformat()
+        bpy.app.handlers.frame_change_post.remove(animate_text)

    def animate_input(self, obj, product_frame):
        if product_frame["type"] in ["LOGISTIC", "MOVE", "DISPOSAL"]:
@@ -17,6 +17,7 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

 import bpy
+import isodate
 import ifcopenshell.api
 import ifcopenshell.util.attribute
 from blenderbim.bim.ifc import IfcStore
@@ -184,6 +185,16 @@ def updateTaskDuration(self, context):
    props = context.scene.BIMWorkScheduleProperties
    if not props.is_task_update_enabled:
        return
+
+    if self.duration == "-":
+        return
+
+    try:
+        isodate.parse_duration(self.duration),
+    except:
+        self.duration = "-"
+        return
+
    self.file = IfcStore.get_file()
    task = self.file.by_id(self.ifc_definition_id)
    if task.TaskTime:
@@ -27,7 +27,7 @@ class BIM_PT_spatial(Panel):
    bl_space_type = "PROPERTIES"
    bl_region_type = "WINDOW"
    bl_context = "object"
-    bl_parent_id = "BIM_PT_geometry_object"
+    bl_parent_id = "BIM_PT_object_metadata"

    @classmethod
    def poll(cls, context):
@@ -21,21 +21,30 @@ from . import ui, prop, operator

 classes = (
    operator.AddStyle,
-    operator.EnableEditingStyle,
    operator.DisableEditingStyle,
+    operator.DisableEditingStyles,
    operator.EditStyle,
+    operator.EnableEditingStyle,
+    operator.LoadStyles,
    operator.RemoveStyle,
-    operator.UpdateStyleColours,
    operator.UnlinkStyle,
+    operator.UpdateStyleColours,
+    operator.UpdateStyleTextures,
+    prop.Style,
+    prop.BIMStylesProperties,
    prop.BIMStyleProperties,
+    ui.BIM_PT_styles,
    ui.BIM_PT_style,
    ui.BIM_PT_style_attributes,
+    ui.BIM_UL_styles,
 )


 def register():
+    bpy.types.Scene.BIMStylesProperties = bpy.props.PointerProperty(type=prop.BIMStylesProperties)
    bpy.types.Material.BIMStyleProperties = bpy.props.PointerProperty(type=prop.BIMStyleProperties)


 def unregister():
+    del bpy.types.Scene.BIMStylesProperties
    del bpy.types.Material.BIMStyleProperties
@@ -18,12 +18,33 @@

 import bpy
 import blenderbim.tool as tool
+import ifcopenshell


 def refresh():
+    StylesData.is_loaded = False
    StyleAttributesData.is_loaded = False


+class StylesData:
+    data = {}
+    is_loaded = False
+
+    @classmethod
+    def load(cls):
+        cls.data = {"style_types": cls.style_types(), "total_styles": cls.total_styles()}
+
+    @classmethod
+    def style_types(cls):
+        declaration = tool.Ifc.schema().declaration_by_name("IfcPresentationStyle")
+        declarations = ifcopenshell.util.schema.get_subtypes(declaration)
+        return [(c, c, "") for c in sorted([d.name() for d in declarations])]
+
+    @classmethod
+    def total_styles(cls):
+        return len(tool.Ifc.get().by_type("IfcPresentationStyle"))
+
+
 class StyleAttributesData:
    data = {}
    is_loaded = False
@@ -20,6 +20,7 @@ import bpy
 import blenderbim.bim.handler
 import blenderbim.tool as tool
 import blenderbim.core.style as core
+import ifcopenshell.util.representation
 from blenderbim.bim.ifc import IfcStore


@@ -39,13 +40,29 @@ class UpdateStyleColours(bpy.types.Operator, Operator):
        core.update_style_colours(tool.Ifc, tool.Style, obj=context.active_object.active_material)


+class UpdateStyleTextures(bpy.types.Operator, Operator):
+    bl_idname = "bim.update_style_textures"
+    bl_label = "Update Style Textures"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def _execute(self, context):
+        representation = ifcopenshell.util.representation.get_representation(
+            tool.Ifc.get_entity(context.active_object), "Model", "Body", "MODEL_VIEW"
+        )
+        if representation:
+            core.update_style_textures(
+                tool.Ifc, tool.Style, obj=context.active_object.active_material, representation=representation
+            )
+
+
 class RemoveStyle(bpy.types.Operator, Operator):
    bl_idname = "bim.remove_style"
    bl_label = "Remove Style"
    bl_options = {"REGISTER", "UNDO"}
+    style: bpy.props.IntProperty()

    def _execute(self, context):
-        core.remove_style(tool.Ifc, tool.Style, obj=context.active_object.active_material)
+        core.remove_style(tool.Ifc, tool.Material, tool.Style, style=tool.Ifc.get().by_id(self.style))


 class AddStyle(bpy.types.Operator, Operator):
@@ -91,3 +108,22 @@ class EditStyle(bpy.types.Operator, Operator):

    def _execute(self, context):
        core.edit_style(tool.Ifc, tool.Style, obj=context.active_object.active_material)
+
+
+class DisableEditingStyles(bpy.types.Operator, Operator):
+    bl_idname = "bim.disable_editing_styles"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_label = "Disable Editing Styles"
+
+    def _execute(self, context):
+        core.disable_editing_styles(tool.Style)
+
+
+class LoadStyles(bpy.types.Operator, Operator):
+    bl_idname = "bim.load_styles"
+    bl_label = "Load Styles"
+    bl_options = {"REGISTER", "UNDO"}
+    style_type: bpy.props.StringProperty()
+
+    def _execute(self, context):
+        core.load_styles(tool.Style, style_type=self.style_type)
@@ -19,6 +19,7 @@
 import bpy
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.prop import StrProperty, Attribute
+from blenderbim.bim.module.style.data import StylesData
 from bpy.types import PropertyGroup
 from bpy.props import (
    PointerProperty,
@@ -32,6 +33,25 @@ from bpy.props import (
 )


+def get_style_types(self, context):
+    if not StylesData.is_loaded:
+        StylesData.load()
+    return StylesData.data["style_types"]
+
+
+class Style(PropertyGroup):
+    name: StringProperty(name="Name")
+    ifc_definition_id: IntProperty(name="IFC Definition ID")
+    total_elements: IntProperty(name="Total Elements")
+
+
+class BIMStylesProperties(PropertyGroup):
+    is_editing: BoolProperty(name="Is Editing")
+    style_type: EnumProperty(items=get_style_types, name="Style Type")
+    styles: CollectionProperty(name="Styles", type=Style)
+    active_style_index: IntProperty(name="Active Style Index")
+
+
 class BIMStyleProperties(PropertyGroup):
    attributes: CollectionProperty(name="Attributes", type=Attribute)
    is_editing: BoolProperty(name="Is Editing")
@@ -17,9 +17,51 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.

 import blenderbim.bim.helper
-from bpy.types import Panel
+from bpy.types import Panel, UIList
 from blenderbim.bim.ifc import IfcStore
-from blenderbim.bim.module.style.data import StyleAttributesData
+from blenderbim.bim.module.style.data import StylesData, StyleAttributesData
+
+
+class BIM_PT_styles(Panel):
+    bl_label = "IFC Styles"
+    bl_idname = "BIM_PT_styles"
+    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):
+        if not StylesData.is_loaded:
+            StylesData.load()
+
+        self.props = context.scene.BIMStylesProperties
+
+        row = self.layout.row(align=True)
+        row.label(text="{} Styles Found".format(StylesData.data["total_styles"]), icon="MATERIAL")
+        row = self.layout.row(align=True)
+        if self.props.is_editing:
+            row.operator("bim.disable_editing_styles", text="", icon="CANCEL")
+        else:
+            row.prop(self.props, "style_type", text="")
+            row.operator("bim.load_styles", text="", icon="IMPORT").style_type = self.props.style_type
+            return
+
+        row = self.layout.row(align=True)
+        row.alignment = "RIGHT"
+
+        #row.operator("bim.add_presentation_style", text="", icon="ADD")
+        if self.props.styles and self.props.active_style_index < len(self.props.styles):
+            style = self.props.styles[self.props.active_style_index]
+        #    op = row.operator("bim.select_by_style", text="", icon="RESTRICT_SELECT_OFF")
+        #    op.style = style.ifc_definition_id
+            row.operator("bim.remove_style", text="", icon="X").style = style.ifc_definition_id
+
+        self.layout.template_list("BIM_UL_styles", "", self.props, "styles", self.props, "active_style_index")


 class BIM_PT_style(Panel):
@@ -42,8 +84,9 @@ class BIM_PT_style(Panel):
        row = self.layout.row(align=True)
        if props.ifc_style_id:
            row.operator("bim.update_style_colours", icon="GREASEPENCIL")
+            row.operator("bim.update_style_textures", icon="TEXTURE", text="")
            row.operator("bim.unlink_style", icon="UNLINKED", text="")
-            row.operator("bim.remove_style", icon="X", text="")
+            row.operator("bim.remove_style", icon="X", text="").style = props.ifc_style_id
        else:
            row.operator("bim.add_style", icon="ADD")

@@ -88,3 +131,13 @@ class BIM_PT_style_attributes(Panel):
                row = self.layout.row(align=True)
                row.label(text=attribute["name"])
                row.label(text=attribute["value"])
+
+
+class BIM_UL_styles(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.name)
+            #row2 = row.row()
+            #row2.alignment = "RIGHT"
+            #row2.label(text=str(item.total_elements))
--- a/Show More
+++ b/Show More