ifcgeom: retry failed batched opening cuts sequentially (#487 )

convert_openings groups openings with similar minimal edge lengths into a single multi-tool BOPAlgo_CUT (batching introduced in 7c1071f588 for robustness and speed on the common case). On the file attached to #487 one such batch of 3 openings fails the interference checks at every fuzziness the retry ladder is allowed to attempt, because the ladder rightly refuses to raise fuzziness past the smallest real edge length of the 20mm recess operand, and the whole batch is dropped, leaving the wall uncut. Each of those openings subtracts cleanly when cut on its own. This adds a gated last resort in boolean_operation: only after a multi-tool CUT has exhausted every fuzziness attempt, reattempt it by applying the same tool operands one at a time, each cut feeding the next. The batched path stays the default; single-tool cuts and non-CUT operations are unaffected, and the fallback is all-or-nothing so a partial sequential success never silently replaces the operand. This change was written with the assistance of an AI coding tool.
Bonsai: fix UnboundLocalError crash in polyline angle calculation
2026-08-07 16:31:37 +00:00 · 2026-07-25 08:34:52 +03:00 · 2026-07-25 13:57:51 +10:00 · 2026-07-24 23:21:18 +01:00 · 2026-07-25 07:47:13 +10:00 · 2026-07-24 21:51:21 +05:00
144 changed files with 2872 additions and 527 deletions
@@ -21,12 +21,12 @@ jobs:

    steps:
      - name: Checkout Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive

      - name: Checkout Build Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/build-outputs
          path: ./build
@@ -9,13 +9,13 @@ jobs:

    steps:
      - name: Checkout Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive
          path: IfcOpenShell

      - name: Checkout Build Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/build-outputs
          path: ifcopenshell_build
@@ -35,12 +35,12 @@ jobs:
          aws --version

      - name: Checkout Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive

      - name: Checkout Build Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/build-outputs
          path: ./build
@@ -35,12 +35,12 @@ jobs:
          aws --version

      - name: Checkout Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive

      - name: Checkout Build Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/build-outputs
          path: ./build
@@ -27,12 +27,12 @@ jobs:

    steps:
      - name: Checkout Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive

      - name: Checkout Build Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/build-outputs
          path: ${{ matrix.deps_dir }}
@@ -19,7 +19,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6 # https://github.com/actions/checkout
+      - uses: actions/checkout@v7 # https://github.com/actions/checkout
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -34,7 +34,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
        with:
          fetch-tags: true
          fetch-depth: 0
@@ -65,7 +65,7 @@ jobs:
            config:
              short_name: macos
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -98,7 +98,7 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout bonsai_unstable_repo repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/bonsai_unstable_repo
          token: ${{ secrets.IFCOPENBOT_TOKEN }}
@@ -48,7 +48,7 @@ jobs:
            config:
              short_name: macos
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -37,7 +37,7 @@ jobs:
            short_name: macosm164
          }
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6
        with:
          python-version: '3.11'
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6
        with:
          python-version: '3.11'
@@ -21,7 +21,7 @@ jobs:
      date: ${{ steps.date.outputs.date }}
      verdate: ${{ steps.verdate.outputs.verdate }}
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - name: Set env
        run: echo ok go
      
@@ -75,7 +75,7 @@ jobs:
            echo "ARTIFACTS_DIR=/home/runner/work/artifacts" >> $GITHUB_ENV
          fi
      
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
        with:
          submodules: recursive

@@ -21,7 +21,7 @@ jobs:
    runs-on: ubuntu-22.04
    needs: activate
    steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
      with:
        submodules: recursive

@@ -86,7 +86,7 @@ jobs:
    name: Docker Build, Tag, Push

    steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
      with:
        lfs: true
    
@@ -47,7 +47,7 @@ jobs:
            short_name: macosm164
          }
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
        with:
          submodules: recursive
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
@@ -38,7 +38,7 @@ jobs:
            short_name: macosm164
          }
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
        with:
          submodules: recursive
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6
        with:
          python-version: '3.11'
@@ -25,7 +25,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -19,7 +19,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -10,9 +10,9 @@ jobs:
  publish_website:
    runs-on: ubuntu-22.04
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - name: Checkout ifctester_org_static_html
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/ifctester_org_static_html
          token: ${{ secrets.IFCOPENBOT_TOKEN }}
@@ -18,7 +18,7 @@ jobs:
    strategy:
      fail-fast: false
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
@@ -34,7 +34,7 @@ jobs:
    runs-on: ubuntu-22.04

    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
        with:
          submodules: recursive

@@ -12,7 +12,7 @@ jobs:
      MIN_BLENDER_PY_VERSION: "3.11"
    steps:
      - name: Action - checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7

      - name: Action - install python
        uses: actions/setup-python@v6
@@ -8,7 +8,7 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout IfcOpenShell
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7

      - name: Install uv
        uses: astral-sh/setup-uv@v7
@@ -25,7 +25,7 @@ jobs:
          echo "name=$(basename $WHEEL)" >> $GITHUB_OUTPUT

      - name: Checkout wasm-wheels
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/wasm-wheels
          path: wasm-wheels
@@ -43,7 +43,7 @@ jobs:
      CLICOLOR_FORCE: "1"
      CMAKE_COLOR_DIAGNOSTICS: "ON"
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
        with:
            submodules: recursive

@@ -257,7 +257,7 @@ jobs:
          cd ../ifcdiff && make test || ERROR=1
          cd ../ifcpatch && make test || ERROR=1
          pip install -e ../ifc5d --no-deps
-          pip install odfpy xlsxwriter
+          pip install odfpy openpyxl
          cd ../ifc5d && make test || ERROR=1
          pip install -e ../ifcquery --no-deps
          cd ../ifcquery && make test || ERROR=1
@@ -11,7 +11,7 @@ jobs:

    steps:
      - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7

      - name: Set up Python
        uses: actions/setup-python@v6
@@ -27,12 +27,12 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout (recursive)
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive
          fetch-depth: 0
      - name: Checkout intermediate Pages repo
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/aichat_ifcopenshell_org_static_html
          ref: gh-pages
@@ -7,7 +7,7 @@ jobs:
  publish:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7

      - uses: astral-sh/setup-uv@v7

@@ -27,12 +27,12 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout (recursive)
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive
          fetch-depth: 0
      - name: Checkout intermediate Pages repo
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          repository: IfcOpenShell/wasm_ifcopenshell_org_static_html
          ref: gh-pages
@@ -17,7 +17,7 @@ jobs:
    runs-on: ubuntu-22.04
    steps:
      - name: Checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
        with:
          submodules: recursive
      - name: Install C++ dependencies
@@ -3,7 +3,7 @@
 <package xmlns="http://schemas.microsoft.com/packaging/2015/06/nuspec.xsd">
  <metadata>
    <id>blenderbim-nightly</id>
-    <version>blenderbim_build_version-alpha</version>
+    <version>blenderbim_build_version</version>
    <packageSourceUrl>https://github.com/IfcOpenShell/IfcOpenShell</packageSourceUrl>
    <owners>fbpyr</owners>
    <!-- == SOFTWARE SPECIFIC SECTION == -->
@@ -3,11 +3,12 @@
 apt update && apt install git wget curl ptpython mono-devel micro
 mkdir -p /home/runner/work/IfcOpenShell && cd /home/runner/work/IfcOpenShell
 git clone https://github.com/IfcOpenShell/IfcOpenShell
-cd /home/runner/work/IfcOpenShell/IfcOpenShell/choco/blenderbim/
+cd /home/runner/work/IfcOpenShell/IfcOpenShell/choco/bonsai/
 micro choco_release.py # paste this script, comment out push command
 export CHOCO_TOKEN="secret_choco_release_token"
 python3 choco_release.py
 """
+
 import datetime
 import hashlib
 import os
@@ -28,7 +29,7 @@ def get_repo_tag_names() -> list[str]:


 def request_repo_info(url: str):
-    req  = request.Request(url)
+    req = request.Request(url)
    resp = request.urlopen(req)
    if not resp.status == 200:
        print(f"[ERROR] could not contact server: {url}")
@@ -85,13 +86,15 @@ def run(command: str) -> None:

 start = datetime.datetime.now()

-URL_CHOCO_PACKAGE  = "https://community.chocolatey.org/packages/blender"
-URL_BLENDER_CMAKE  = "https://raw.githubusercontent.com/blender/blender/{}/build_files/cmake/Modules/FindPythonLibsUnix.cmake"
-RE_BLENDER_VERSION_MIN_MAJ        = r"Latest Version.+<span>Blender (\d+\.\d+)\..+</span>"
-RE_BLENDER_VERSION_MIN_MAJ_PAT    = r"Latest Version.+<span>Blender (\d+\.\d+\.\d+)</span>"
+URL_CHOCO_PACKAGE = "https://community.chocolatey.org/packages/blender"
+URL_BLENDER_CMAKE = (
+    "https://raw.githubusercontent.com/blender/blender/{}/build_files/cmake/Modules/FindPythonLibsUnix.cmake"
+)
+RE_BLENDER_VERSION_MIN_MAJ = r"Latest Version.+<span>Blender (\d+\.\d+)\..+</span>"
+RE_BLENDER_VERSION_MIN_MAJ_PAT = r"Latest Version.+<span>Blender (\d+\.\d+\.\d+)</span>"
 RE_BLENDER_PYTHON_VERSION_MAJ_MIN = r"\(_PYTHON_VERSION_SUPPORTED (\d+\.\d+)\)"

-BLENDERBIM_DIR = pathlib.Path("/home/runner/work/IfcOpenShell/IfcOpenShell/choco/blenderbim/")
+BLENDERBIM_DIR = pathlib.Path("/home/runner/work/IfcOpenShell/IfcOpenShell/choco/bonsai/")

 print("_____ check choco release needed?")

@@ -148,7 +151,7 @@ print(f"{blender_python_version_maj_min=}")
 python_version = f"py{found[0].replace('.', '')}"
 print(f"{python_version=}")

-blenderbim_build_version = target_release_tag.replace("blenderbim-", "")
+blenderbim_build_version = target_release_tag.replace("bonsai-", "")

 # url_blenderbim_py3x_win_zip
 release_zip_file_name, url_blenderbim_py3x_win_zip = get_release_zip(target_release_tag)
@@ -166,15 +169,15 @@ topics = {
        "path": HERE_DIR / "blenderbim.nuspec",
        "key_values": {
            "latest_blender_version_maj_min_pat": latest_blender_release_maj_min_pat,
-            "blenderbim_build_version"          : blenderbim_build_version,
+            "blenderbim_build_version": blenderbim_build_version,
        },
    },
    "install": {
        "path": HERE_DIR / "tools" / "chocolateyinstall.ps1",
        "key_values": {
-            "url_blenderbim_py3x_win_zip"      : url_blenderbim_py3x_win_zip,
+            "url_blenderbim_py3x_win_zip": url_blenderbim_py3x_win_zip,
            "sha256sum_blenderbim_py3x_win_zip": sha256sum_blenderbim_py3x_win_zip,
-            "latest_blender_version_maj_min"   : blender_version_min_maj,
+            "latest_blender_version_maj_min": blender_version_min_maj,
        },
    },
    "uninstall": {
@@ -121,7 +121,7 @@ import tarfile
 import threading
 from datetime import datetime

-ssl._create_default_https_context = ssl._create_unverified_context
+ssl._create_default_https_context = ssl._create_unverified_context  # ty:ignore[invalid-assignment]

 import time
 from collections.abc import Generator, Sequence
@@ -697,7 +697,10 @@ def build_dependency(
            compr = "xz"
        else:
            raise RuntimeError("fix source for new download type")
-        download_tarfile = tarfile.open(name=download_tarfile_path, mode=f"r:{compr}")
+        # ty: false positive bug upstream.
+        download_tarfile = tarfile.open(
+            name=download_tarfile_path, mode=f"r:{compr}"
+        )  # ty:ignore[no-matching-overload]
        # tarfile seriously doesn't have a function to retrieve the root directory more easily
        extract_dir_name = os.path.commonprefix([x for x in download_tarfile.getnames() if x != "."])
        # run([tar, "--exclude=\"*/*\"", "-tf", download_name], cwd=build_dir).strip() no longer works
@@ -156,7 +156,8 @@ exclude = [
 [tool.poe.tasks]

 dev-setup.sequence = [
-    {cmd = "uv sync"},
+    # 3.13 is chosen because it's the version used in the latest Bonsai.
+    {cmd = "uv sync --python 3.13"},
    {cmd = "uv pip install -e ./src/bsdd/"},
    {cmd = "uv pip install -e ./src/ifcopenshell-python/[advanced,dev]"},
    {cmd = "uv pip install -e ./src/ifcedit/"},
@@ -1,5 +1,5 @@
 black==26.3.1
-ruff==0.15.12
+ruff==0.16.0
 poethepoet
-ty==0.0.61
-gersemi==0.26.1
+ty==0.0.63
+gersemi==0.28.0
@@ -5,7 +5,7 @@ FILE_NAME('EPset_Drawing.ifc','2020-01-01T00:00:00',$,$,'EPset_Drawing','EPset_D
 FILE_SCHEMA(('IFC4'));
 ENDSEC;
 DATA;
-#1=IFCPROPERTYSETTEMPLATE('2JhNIvqZrFnAgxfhK0XVQX',$,'EPset_Drawing','',.PSET_OCCURRENCEDRIVEN.,'IfcAnnotation/DRAWING',(#23,#22,#27,#24,#29,#30,#19,#12,#26,#9,#8,#7,#6,#4,#18,#11,#5,#20,#25,#14,#10,#17,#28,#16,#3,#21,#13,#15,#2,#31,#32,#33,#34,#35,#36));
+#1=IFCPROPERTYSETTEMPLATE('2JhNIvqZrFnAgxfhK0XVQX',$,'EPset_Drawing','',.PSET_OCCURRENCEDRIVEN.,'IfcAnnotation/DRAWING',(#23,#22,#27,#24,#29,#30,#19,#12,#26,#9,#8,#7,#6,#4,#18,#11,#5,#20,#25,#14,#10,#17,#28,#16,#3,#21,#13,#15,#2,#31,#32,#33,#34,#35,#36,#37));
 #2=IFCSIMPLEPROPERTYTEMPLATE('23JavTMk98ZxXhrUEnjAcf',$,'TargetView','',.P_SINGLEVALUE.,'IfcLabel',$,$,$,$,$,.READWRITE.);
 #3=IFCSIMPLEPROPERTYTEMPLATE('1yVWUt5H9DAOuu0OaMMLpe',$,'Scale','The scale of this drawing represented as a numerator and denominator, such as 1/100',.P_SINGLEVALUE.,'IfcLabel',$,$,$,$,$,.READWRITE.);
 #4=IFCSIMPLEPROPERTYTEMPLATE('3gsuPBtU93b8f0gg1pjkq6',$,'HumanScale','The scale of this drawing in human readable format, such as 1:100',.P_SINGLEVALUE.,'IfcLabel',$,$,$,$,$,.READWRITE.);
@@ -41,5 +41,6 @@ DATA;
 #34=IFCSIMPLEPROPERTYTEMPLATE('2epSGfC4bFM9gb1X7zBIp4',$,'RenderSharp','Whether to render ''sharp'' (convex) edges. Only relevant when UseEdgeClassification is enabled.',.P_SINGLEVALUE.,'IfcBoolean',$,$,$,$,$,.READWRITE.);
 #35=IFCSIMPLEPROPERTYTEMPLATE('3TZwsEjkr5WRDKcgrYzSIA',$,'RidgeAngleMinDegrees','Minimum convex dihedral deviation from flat, in degrees, for a projection edge to be classified as ''sharp'' rather than ''flush''.',.P_SINGLEVALUE.,'IfcReal',$,$,$,$,$,.READWRITE.);
 #36=IFCSIMPLEPROPERTYTEMPLATE('2Jua$lO754vgZOkBoHM2gA',$,'RenderFlush','Whether to render ''flush'' edges (dihedral deviation below both ridge/valley thresholds). Only relevant when UseEdgeClassification is enabled.',.P_SINGLEVALUE.,'IfcBoolean',$,$,$,$,$,.READWRITE.);
+#37=IFCSIMPLEPROPERTYTEMPLATE('1zM9sia2L8RQDnWZxgUwlZ',$,'JoinClasses','Comma separated list of IFC classes whose cut linework will be joined together when they meet (e.g. mitred at a corner).\X2\000A\X0\Defaults to ''IfcWall,IfcSlab'' if not set. Override to also join other classes, such as ''IfcWall,IfcSlab,IfcCovering''.',.P_SINGLEVALUE.,'IfcText',$,$,$,$,$,.READWRITE.);
 ENDSEC;
 END-ISO-10303-21;
@@ -10,6 +10,7 @@ if bonsai_lib_path:
 import argparse
 import base64
 import json
+import urllib.parse
 import xml.etree.ElementTree as ET

 import pystache
@@ -18,8 +19,53 @@ from aiohttp import web

 sio_port = 8080  # default port

+
+def get_asset_version() -> str:
+    """A cache-busting token appended to locally served static asset URLs.
+
+    Browsers otherwise keep serving a stale cached copy of static/js and
+    static/css after Bonsai ships a code change, until the user does a hard
+    refresh. Using the Bonsai version (which includes the build's commit
+    hash) means the token changes on every shipped update.
+    """
+    if bonsai_version:
+        return urllib.parse.quote(bonsai_version, safe="")
+    # Fallback for standalone runs without BONSAI_VERSION set (e.g. running
+    # sioserver.py directly outside of Blender): derive a token from the
+    # newest mtime among the static assets, so it still changes whenever the
+    # shipped files change.
+    static_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), "static")
+    latest_mtime = 0
+    for root, _dirs, files in os.walk(static_dir):
+        for name in files:
+            latest_mtime = max(latest_mtime, int(os.path.getmtime(os.path.join(root, name))))
+    return f"dev-{latest_mtime}"
+
+
+asset_version = get_asset_version()
+
+
+@web.middleware
+async def no_cache_static_middleware(request: web.Request, handler):
+    """Force revalidation of locally served static assets.
+
+    Query-string version stamping (see `asset_version`) busts the cache for
+    the HTML-referenced entry points, but JS files that statically import
+    other local modules (e.g. cost.js/gantt.js importing utilities/costui.js)
+    reference those modules by an un-stamped relative path. Marking all
+    /static/ and /jsgantt/ responses as no-cache makes browsers always
+    revalidate with the server (a cheap conditional GET / 304 when nothing
+    changed), so nested imports also pick up shipped changes without
+    requiring a hard refresh.
+    """
+    response = await handler(request)
+    if request.path.startswith("/static/") or request.path.startswith("/jsgantt/"):
+        response.headers["Cache-Control"] = "no-cache, must-revalidate"
+    return response
+
+
 sio = socketio.AsyncServer(cors_allowed_origins="*", async_mode="aiohttp", max_http_buffer_size=10000000)
-app = web.Application()
+app = web.Application(middlewares=[no_cache_static_middleware])
 sio.attach(app)


@@ -199,28 +245,28 @@ class BlenderNamespace(socketio.AsyncNamespace):
 async def schedules(request):
    with open("templates/index.html", "r") as f:
        template = f.read()
-    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version})
+    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version, "v": asset_version})
    return web.Response(text=html_content, content_type="text/html")


 async def costing(request):
    with open("templates/costing.html", "r") as f:
        template = f.read()
-    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version})
+    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version, "v": asset_version})
    return web.Response(text=html_content, content_type="text/html")


 async def sequencing(request):
    with open("templates/gantt.html", "r") as f:
        template = f.read()
-    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version})
+    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version, "v": asset_version})
    return web.Response(text=html_content, content_type="text/html")


 async def documentation(request):
    with open("templates/drawings.html", "r") as f:
        template = f.read()
-    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version})
+    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version, "v": asset_version})
    return web.Response(text=html_content, content_type="text/html")


@@ -229,7 +275,7 @@ async def documentation(request):
 async def demo(request):
    with open("templates/demo.html", "r") as f:
        template = f.read()
-    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version})
+    html_content = pystache.render(template, {"port": sio_port, "version": bonsai_version, "v": asset_version})
    return web.Response(text=html_content, content_type="text/html")


@@ -244,7 +244,7 @@ function addGanttElement(blenderId, tasks, workSched, filename) {
      vShowTaskInfoLink: 1, // Show link in tool tip (0/1)
      vShowEndWeekDate: 0, // Show/Hide the date for the last day of the week in header for daily
      vUseSingleCell: 10000, // Set the threshold cell per table row (Helps performance for large data.
-      vFormatArr: ["Day", "Week", "Month", "Quarter"], // Even with setUseSingleCell using Hour format on such a large chart can cause issues in some browsers,
+      vFormatArr: ["Hour", "Day", "Week", "Month", "Quarter"], // vUseSingleCell keeps Hour usable on large charts.
      vShowRes: true, // 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.
@@ -250,6 +250,14 @@ export class CostUI {
      },
    });

+    CostUI.addRibbonButton({
+      text: "Download CSV",
+      icon: "fa-solid fa-file-csv",
+      callback: () => {
+        CostUI.downloadCsv();
+      },
+    });
+
    CostUI.addRibbonButton({
      text: "Hide Schedules",
      icon: "fa-regular fa-eye-slash",
@@ -523,6 +531,81 @@ export class CostUI {
    }
  }

+  static downloadCsv() {
+    const tables = document.querySelectorAll("table[id^='cost-items-']");
+    if (tables.length === 0) {
+      alert("No cost schedule loaded to export!");
+      return;
+    }
+    tables.forEach((table) => {
+      const scheduleId = table.id.split("-").pop();
+      const csv = CostUI.tableToCsv(table);
+      if (csv === null) {
+        return;
+      }
+      const nameEl = document.querySelector(
+        "#cost-schedule-container-" + scheduleId + " .form-header span"
+      );
+      const scheduleName = nameEl
+        ? nameEl.textContent
+        : "cost_schedule_" + scheduleId;
+      CostUI.triggerCsvDownload(csv, scheduleName + ".csv");
+    });
+  }
+
+  static tableToCsv(table) {
+    const escapeCsvCell = (value) => {
+      const text = (value === null || value === undefined ? "" : value)
+        .toString()
+        .trim();
+      if (/[",\n]/.test(text)) {
+        return '"' + text.replace(/"/g, '""') + '"';
+      }
+      return text;
+    };
+
+    const cellText = (cell) => {
+      const input = cell.querySelector("input");
+      return input ? input.value : cell.innerText;
+    };
+
+    // The Actions column only holds buttons (edit/delete/etc), not data.
+    const isDataColumn = (column) => column && column !== "Actions";
+
+    const headerCells = Array.from(table.querySelectorAll("thead th")).filter(
+      (th) => isDataColumn(th.getAttribute("data-column"))
+    );
+    if (headerCells.length === 0) {
+      return null;
+    }
+
+    const rows = [headerCells.map((th) => escapeCsvCell(th.textContent)).join(",")];
+
+    table.querySelectorAll("tbody tr").forEach((row) => {
+      const cells = Array.from(row.children).filter((cell) =>
+        isDataColumn(cell.getAttribute("data-column"))
+      );
+      if (cells.length === 0) {
+        return; // e.g. the "No cost items found" placeholder row.
+      }
+      rows.push(cells.map((cell) => escapeCsvCell(cellText(cell))).join(","));
+    });
+
+    return rows.join("\n");
+  }
+
+  static triggerCsvDownload(csvContent, filename) {
+    const blob = new Blob([csvContent], { type: "text/csv;charset=utf-8;" });
+    const url = URL.createObjectURL(blob);
+    const link = document.createElement("a");
+    link.href = url;
+    link.download = filename;
+    document.body.appendChild(link);
+    link.click();
+    document.body.removeChild(link);
+    URL.revokeObjectURL(url);
+  }
+
  static createCostTable({ costSchedule, currency, callbacks }) {
    const preferences = CostUI.getColumnPreferences();
    const isScheduleOfRates = costSchedule.PredefinedType === "SCHEDULEOFRATES";
@@ -7,7 +7,7 @@
    <link
      rel="stylesheet"
      type="text/css"
-      href="/static/css/cost.css"
+      href="/static/css/cost.css?v={{v}}"
      id="index-stylesheet"
    />
    <link
@@ -21,7 +21,7 @@
    />
    <script
      type="text/javascript"
-      src="/static/js/jquery.min.js"
+      src="/static/js/jquery.min.js?v={{v}}"
    ></script>
    <script
      type="text/javascript"
@@ -34,7 +34,7 @@
    <script>
      var SOCKET_PORT = {{port}};
    </script>
-    <script type="module" defer src="./static/js/cost.js"></script>
+    <script type="module" defer src="./static/js/cost.js?v={{v}}"></script>
  </head>
  <body>
    <nav>
@@ -12,14 +12,14 @@
    />
    <!-- here we request the CSS file from the server, -->
    <!-- using registered static path in the server -->
-    <link rel="stylesheet" href="/static/css/demo.css" id="demo-stylesheet" />
+    <link rel="stylesheet" href="/static/css/demo.css?v={{v}}" id="demo-stylesheet" />
    <link
      rel="stylesheet"
      href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.6.0/css/all.min.css"
    />
    <script
      type="text/javascript"
-      src="/static/js/jquery.min.js"
+      src="/static/js/jquery.min.js?v={{v}}"
    ></script>
    <script
      type="text/javascript"
@@ -33,7 +33,7 @@
    </script>
    <!-- here we request the JS file from the server-->
    <!-- using registered static path in the server -->
-    <script defer src="./static/js/demo.js"></script>
+    <script defer src="./static/js/demo.js?v={{v}}"></script>
  </head>
  <body>
    <!-- the navigation bar at the top of the page. -->
@@ -15,7 +15,7 @@
    />
    <link
      rel="stylesheet"
-      href="/static/css/drawings.css"
+      href="/static/css/drawings.css?v={{v}}"
      id="drawings-stylesheet"
    />
    <link
@@ -24,7 +24,7 @@
    />
    <script
      type="text/javascript"
-      src="/static/js/jquery.min.js"
+      src="/static/js/jquery.min.js?v={{v}}"
    ></script>
    <script
      type="text/javascript"
@@ -45,7 +45,7 @@
    <script>
      var SOCKET_PORT = {{port}};
    </script>
-    <script defer src="./static/js/drawings.js"></script>
+    <script defer src="./static/js/drawings.js?v={{v}}"></script>
  </head>
  <body>
    <nav>
@@ -9,25 +9,25 @@
      type="image/x-icon"
      href="https://bonsaibim.org/assets/images/favicon-blender.png"
    />
-    <link rel="stylesheet" type="text/css" href="/jsgantt/jsgantt.css" />
-    <link rel="stylesheet" href="/static/css/gantt.css" id="gantt-stylesheet" />
+    <link rel="stylesheet" type="text/css" href="/jsgantt/jsgantt.css?v={{v}}" />
+    <link rel="stylesheet" href="/static/css/gantt.css?v={{v}}" id="gantt-stylesheet" />
    <link
      rel="stylesheet"
      href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.6.0/css/all.min.css"
    />
    <script
      type="text/javascript"
-      src="/static/js/jquery.min.js"
+      src="/static/js/jquery.min.js?v={{v}}"
    ></script>
    <script
      type="text/javascript"
      src="https://cdn.socket.io/4.0.0/socket.io.min.js"
    ></script>
-    <script type="text/javascript" src="./jsgantt/jsgantt.js"></script>
+    <script type="text/javascript" src="./jsgantt/jsgantt.js?v={{v}}"></script>
    <script>
      var SOCKET_PORT = {{port}};
    </script>
-    <script type="module" defer src="./static/js/gantt.js"></script>
+    <script type="module" defer src="./static/js/gantt.js?v={{v}}"></script>
  </head>
  <body>
    <nav class="no-print">
@@ -9,7 +9,7 @@
      type="image/x-icon"
      href="https://bonsaibim.org/assets/images/favicon-blender.png"
    />
-    <link rel="stylesheet" href="/static/css/index.css" id="index-stylesheet" />
+    <link rel="stylesheet" href="/static/css/index.css?v={{v}}" id="index-stylesheet" />
    <link
      rel="stylesheet"
      id="tabulator-stylesheet"
@@ -21,7 +21,7 @@
    />
    <script
      type="text/javascript"
-      src="/static/js/jquery.min.js"
+      src="/static/js/jquery.min.js?v={{v}}"
    ></script>
    <script
      type="text/javascript"
@@ -34,7 +34,7 @@
    <script>
      var SOCKET_PORT = {{port}};
    </script>
-    <script defer src="./static/js/index.js"></script>
+    <script defer src="./static/js/index.js?v={{v}}"></script>
  </head>
  <body>
    <nav>
@@ -418,9 +418,10 @@ def get_user(ifc: ifcopenshell.file) -> Union[ifcopenshell.entity_instance, None


 def viewport_shading_changed_callback(area: bpy.types.Area) -> None:
-    shading = area.spaces.active.shading.type
-    if shading == "RENDERED":
-        tool.Style.get_style_props().active_style_type = "External"
+    shading_type = area.spaces.active.shading.type
+    tool.Style.restore_material_style_types(shading_type)
+    if shading_type == "SOLID":
+        area.spaces.active.shading.color_type = "MATERIAL"


 def subscribe_to_viewport_shading_changes():
@@ -133,10 +133,6 @@ class MaterialCreator:
                if shape_has_openings and coords.is_a("IfcIndexedTextureMap"):
                    continue
                tool.Loader.load_indexed_map(coords, self.mesh)
-            elif tool.Style.get_texture_style(material):
-                # No explicit coordinate mapping (e.g. IFC2X3 has no IsMappedBy,
-                # and IFC4 COORD uses generated UVs). Bake XY→UV as fallback.
-                tool.Loader.load_generated_uv_map(self.mesh)

    def assign_material_slots_to_faces(self) -> None:
        if not self.mesh["ios_materials"]:
@@ -47,6 +47,7 @@ classes = (
    operator.CleanWireframes,
    operator.ContractSheet,
    operator.ConvertSVGToDXF,
+    operator.CopyAnnotationToDrawing,
    operator.CopyTextToSelection,
    operator.CreateDrawing,
    operator.CreateSheets,
@@ -107,6 +108,7 @@ classes = (
    operator.SelectAssignedProduct,
    operator.SelectSimilarTextLiteralValue,
    operator.ToggleTargetView,
+    operator.ToggleDrawingCategorySelection,
    operator.OpenDocumentationWebUi,
    operator.FilterSelectedObjectsIfIntersectedByCamera,
    prop.Variable,
@@ -228,6 +228,90 @@ class DuplicateDrawing(bpy.types.Operator, tool.Ifc.Operator):
        )


+def get_copy_annotation_target_drawings(self, context):
+    global COPY_ANNOTATION_TARGET_DRAWINGS_ENUM
+    drawings = [e for e in tool.Ifc.get().by_type("IfcAnnotation") if e.ObjectType == "DRAWING"]
+    drawings.sort(key=lambda d: d.Name or "")
+    COPY_ANNOTATION_TARGET_DRAWINGS_ENUM = [(str(d.id()), d.Name or "Unnamed", "") for d in drawings]
+    return COPY_ANNOTATION_TARGET_DRAWINGS_ENUM
+
+
+COPY_ANNOTATION_TARGET_DRAWINGS_ENUM = []
+
+
+class CopyAnnotationToDrawing(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.copy_annotation_to_drawing"
+    bl_label = "Copy Annotation To Drawing"
+    bl_description = (
+        "Copy the selected annotations to another drawing.\n\n"
+        "The copies become independent annotations assigned to the chosen drawing, "
+        "placed in its view plane. The originals stay in their current drawing"
+    )
+    bl_options = {"REGISTER", "UNDO"}
+    target_drawing: bpy.props.EnumProperty(name="Target Drawing", items=get_copy_annotation_target_drawings)
+
+    if TYPE_CHECKING:
+        target_drawing: str
+
+    @classmethod
+    def poll(cls, context):
+        if not tool.Ifc.get():
+            cls.poll_message_set("No IFC project loaded.")
+            return False
+        if not cls.get_selected_annotations(context):
+            cls.poll_message_set("No annotation selected.")
+            return False
+        return True
+
+    @classmethod
+    def get_selected_annotations(cls, context) -> list[ifcopenshell.entity_instance]:
+        return [
+            element
+            for obj in context.selected_objects
+            if (element := tool.Ifc.get_entity(obj))
+            and element.is_a("IfcAnnotation")
+            and element.ObjectType != "DRAWING"
+        ]
+
+    def invoke(self, context, event):
+        assert context.window_manager
+        return context.window_manager.invoke_props_dialog(self)
+
+    def draw(self, context):
+        assert self.layout
+        row = self.layout.row()
+        row.prop(self, "target_drawing")
+
+    def _execute(self, context):
+        if not self.target_drawing:
+            self.report({"ERROR"}, "No target drawing selected.")
+            return {"CANCELLED"}
+        target_drawing = tool.Ifc.get().by_id(int(self.target_drawing))
+        annotations = self.get_selected_annotations(context)
+        previous_selection = [obj for a in annotations if (obj := tool.Ifc.get_object(a))]
+        previous_active = context.view_layer.objects.active
+        copied = core.copy_annotations_to_drawing(
+            tool.Ifc,
+            tool.Collector,
+            tool.Drawing,
+            tool.Geometry,
+            annotations=annotations,
+            target_drawing=target_drawing,
+        )
+        for obj in context.selected_objects:
+            obj.select_set(False)
+        for obj in previous_selection:
+            if obj.name in context.view_layer.objects:
+                obj.select_set(True)
+        if previous_active and previous_active.name in context.view_layer.objects:
+            context.view_layer.objects.active = previous_active
+        skipped = len(annotations) - len(copied)
+        message = f"Copied {len(copied)} annotations to {target_drawing.Name or 'Unnamed'}."
+        if skipped:
+            message += f" Skipped {skipped} already in that drawing."
+        self.report({"INFO"}, message)
+
+
 class CreateDrawing(bpy.types.Operator):
    """Creates/refreshes a .svg drawing

@@ -1471,6 +1555,15 @@ class CreateDrawing(bpy.types.Operator):
                "Material.Name",
            ]

+        join_classes = ifcopenshell.util.element.get_pset(self.camera_element, "EPset_Drawing", "JoinClasses")
+        if join_classes:
+            join_classes = tuple(c.strip() for c in join_classes.split(",") if c.strip())
+        else:
+            # Architectural convention only merges these objects by default. E.g. pipe
+            # segments and fittings shouldn't merge. Users may override this per-drawing
+            # via the EPset_Drawing.JoinClasses property (e.g. to also join IfcCovering).
+            join_classes = ("IfcWall", "IfcSlab")
+
        group = root.find("{http://www.w3.org/2000/svg}g")
        joined_paths = {}
        self.is_manifold_cache = {}
@@ -1572,8 +1665,7 @@ class CreateDrawing(bpy.types.Operator):
                            )
                        path.attrib["d"] = d

-            # Architectural convention only merges these objects. E.g. pipe segments and fittings shouldn't merge.
-            if not element.is_a("IfcWall") and not element.is_a("IfcSlab"):
+            if not any(element.is_a(c) for c in join_classes):
                continue

            keys = []
@@ -2218,7 +2310,11 @@ class SelectAllDrawings(bpy.types.Operator):

    def execute(self, context):
        props = tool.Drawing.get_document_props()
+        # When filtering to sheeted drawings only, act on the visible drawings only.
+        sheeted_ids = tool.Drawing.get_sheeted_drawing_ids() if props.show_drawings_on_sheets_only else None
        for drawing in props.drawings:
+            if sheeted_ids is not None and drawing.is_drawing and drawing.ifc_definition_id not in sheeted_ids:
+                continue
            if drawing.is_selected != self.select_all:
                drawing.is_selected = self.select_all
        return {"FINISHED"}
@@ -3778,6 +3874,26 @@ class ToggleTargetView(bpy.types.Operator):
        return {"FINISHED"}


+class ToggleDrawingCategorySelection(bpy.types.Operator):
+    bl_idname = "bim.toggle_drawing_category_selection"
+    bl_label = "Toggle Category Selection"
+    bl_description = "Select or deselect all drawings in this view category"
+    bl_options = {"REGISTER", "UNDO"}
+
+    target_view: bpy.props.StringProperty()
+
+    if TYPE_CHECKING:
+        target_view: str
+
+    def execute(self, context):
+        drawings = tool.Drawing.get_visible_drawings_in_category(self.target_view)
+        # If everything visible in the category is already selected, deselect all; otherwise select all.
+        new_state = not all(d.is_selected for d in drawings)
+        for drawing in drawings:
+            drawing.is_selected = new_state
+        return {"FINISHED"}
+
+
 class ExpandSheet(bpy.types.Operator):
    bl_idname = "bim.expand_sheet"
    bl_label = "Expand Sheet"
@@ -409,6 +409,12 @@ class DocProperties(PropertyGroup):
        options=set(),
    )
    is_editing_drawings: BoolProperty(name="Is Editing Drawings", default=False)
+    show_drawings_on_sheets_only: BoolProperty(
+        name="Show Only Drawings on Sheets",
+        description="Only show drawings that are placed on a sheet",
+        default=False,
+        options=set(),
+    )
    is_editing_schedules: BoolProperty(name="Is Editing Schedules", default=False)
    is_editing_references: BoolProperty(name="Is Editing References", default=False)
    target_view: EnumProperty(
@@ -439,6 +445,7 @@ class DocProperties(PropertyGroup):
        should_use_annotation_cache: bool
        should_draw_linked_projects: bool
        is_editing_drawings: bool
+        show_drawings_on_sheets_only: bool
        is_editing_schedules: bool
        is_editing_references: bool
        target_view: Literal["PLAN_VIEW", "ELEVATION_VIEW", "SECTION_VIEW", "REFLECTED_PLAN_VIEW", "MODEL_VIEW"]
@@ -332,6 +332,8 @@ class BIM_PT_drawings(Panel):

                row3.separator(factor=0.5, type="SPACE")

+                row3.operator("bim.copy_annotation_to_drawing", icon="PASTEDOWN", text="")
+
                row3.operator("bim.select_all_drawings", icon="CHECKBOX_HLT", text="")
                row3.operator("bim.create_drawing", text="", icon="OUTPUT")
                row3.operator("bim.convert_svg_to_dxf", text="", icon="SEQ_PREVIEW").view = active_drawing.name
@@ -339,6 +341,7 @@ class BIM_PT_drawings(Panel):
            self.layout.template_list(
                "BIM_UL_drawinglist", "", self.props, "drawings", self.props, "active_drawing_index"
            )
+            self.layout.prop(self.props, "show_drawings_on_sheets_only")


 class BIM_PT_schedules(Panel):
@@ -871,8 +874,8 @@ class BIM_UL_drawinglist(bpy.types.UIList):
            layout.label(text="", translate=False)
            return

-        row = layout.row(align=True)
        if item.is_drawing:
+            row = layout.row(align=True)
            row.label(text="", icon="BLANK1")
            selected_icon = "CHECKBOX_HLT" if item.is_selected else "CHECKBOX_DEHLT"
            row.prop(item, "is_selected", text="", icon=selected_icon, emboss=False)
@@ -893,6 +896,9 @@ class BIM_UL_drawinglist(bpy.types.UIList):
                    item.ifc_definition_id
                )
        else:
+            # Give category headers a distinct inset background so they stand out from drawing rows.
+            box = layout.box()
+            row = box.row(align=True)
            if item.target_view == "PLAN_VIEW":
                icon = "UV_FACESEL"
            elif item.target_view == "ELEVATION_VIEW":
@@ -913,7 +919,55 @@ class BIM_UL_drawinglist(bpy.types.UIList):
                op = row.operator("bim.toggle_target_view", text="", emboss=False, icon="DISCLOSURE_TRI_RIGHT")
                op.target_view = item.target_view
                op.option = "EXPAND"
-            row.prop(item, "name", text="", icon=icon, emboss=False)
+            group = tool.Drawing.get_visible_drawings_in_category(item.target_view)
+            all_selected = bool(group) and all(d.is_selected for d in group)
+            row.operator(
+                "bim.toggle_drawing_category_selection",
+                text="",
+                icon="CHECKBOX_HLT" if all_selected else "CHECKBOX_DEHLT",
+                emboss=False,
+            ).target_view = item.target_view
+            row.separator(factor=0.5, type="SPACE")
+            # Clicking the header name toggles expand/contract, same as the disclosure triangle.
+            op = row.operator("bim.toggle_target_view", text=item.name, icon=icon, emboss=False)
+            op.target_view = item.target_view
+            op.option = "CONTRACT" if item.is_expanded else "EXPAND"
+
+    def filter_items(self, context, data: DocProperties, propname: str):
+        drawings = getattr(data, propname)
+        helper_funcs = bpy.types.UI_UL_list
+
+        flt_flags = []
+        flt_neworder = []
+
+        if self.filter_name:
+            flt_flags = helper_funcs.filter_items_by_name(
+                self.filter_name,
+                self.bitflag_filter_item,
+                drawings,
+                "name",
+                reverse=self.use_filter_sort_reverse,
+            )
+        if not flt_flags:
+            flt_flags = [self.bitflag_filter_item] * len(drawings)
+
+        props = tool.Drawing.get_document_props()
+        if props.show_drawings_on_sheets_only:
+            ifc_file = tool.Ifc.get()
+            sheeted_ids = tool.Drawing.get_sheeted_drawing_ids()
+            # Target view headers are only shown if they contain a sheeted drawing.
+            sheeted_target_views = {
+                tool.Drawing.get_drawing_target_view(ifc_file.by_id(drawing_id)) for drawing_id in sheeted_ids
+            }
+            for i, item in enumerate(drawings):
+                if item.is_drawing:
+                    is_visible = item.ifc_definition_id in sheeted_ids
+                else:
+                    is_visible = item.target_view in sheeted_target_views
+                if not is_visible:
+                    flt_flags[i] &= ~self.bitflag_filter_item
+
+        return flt_flags, flt_neworder


 class BIM_UL_sheets(bpy.types.UIList):
@@ -225,6 +225,9 @@ class AnnotationToolUI:
    def draw_edit_object_interface(cls, context):
        if DecoratorData.get_text_data(bpy.context.active_object):
            add_layout_hotkey_operator(cls.layout, "Edit Text", "S_E", "")
+        if bpy.ops.bim.copy_annotation_to_drawing.poll():
+            row = cls.layout.row(align=True)
+            row.operator("bim.copy_annotation_to_drawing", icon="PASTEDOWN", text="Copy To Drawing")

    @classmethod
    def draw_type_selection_interface(cls):
@@ -163,14 +163,52 @@ class AssignGroup(bpy.types.Operator, tool.Ifc.Operator):
    def _execute(self, context):
        if not self.is_assigning:
            return bpy.ops.bim.unassign_group(group=self.group)
+        ifc_file = tool.Ifc.get()
+        group = ifc_file.by_id(self.group)
        products = [
            element
            for o in tool.Blender.get_selected_objects(include_active=False)
            if (element := tool.Ifc.get_entity(o))
        ]
-        ifcopenshell.api.group.assign_group(tool.Ifc.get(), products=products, group=tool.Ifc.get().by_id(self.group))
+        relocated_annotations = self.unassign_from_previous_drawing(ifc_file, group, products)
+        ifcopenshell.api.group.assign_group(ifc_file, products=products, group=group)
+        self.relocate_annotations_to_drawing(relocated_annotations, group)
        self.report({"INFO"}, f"Assigned {len(products)} objects to group.")

+    def unassign_from_previous_drawing(self, ifc_file, group, products) -> list[ifcopenshell.entity_instance]:
+        """Assigning an annotation to a group that represents a drawing means the
+        annotation should belong to that drawing only, so it needs to leave
+        whichever drawing it was previously part of, instead of ending up
+        visible in both at once.
+        """
+        new_drawing = tool.Drawing.get_group_drawing(group)
+        if not new_drawing:
+            return []
+        relocated = []
+        for product in products:
+            if not product.is_a("IfcAnnotation") or product.ObjectType == "DRAWING":
+                continue
+            old_drawing = tool.Drawing.get_annotation_drawing(product)
+            if not old_drawing or old_drawing.id() == new_drawing.id():
+                continue
+            if old_group := tool.Drawing.get_drawing_group(old_drawing):
+                ifcopenshell.api.group.unassign_group(ifc_file, products=[product], group=old_group)
+            relocated.append(product)
+        return relocated
+
+    def relocate_annotations_to_drawing(self, products, group) -> None:
+        """Move the relocated annotations into the new drawing's collection and
+        depth, now that they have actually been assigned to its group.
+        """
+        if not products:
+            return
+        new_drawing = tool.Drawing.get_group_drawing(group)
+        new_camera = tool.Ifc.get_object(new_drawing) or tool.Drawing.import_drawing(new_drawing)
+        for product in products:
+            if obj := tool.Ifc.get_object(product):
+                tool.Drawing.ensure_annotation_in_drawing_plane(obj, camera=new_camera)
+                tool.Collector.assign(obj)
+

 class UnassignGroup(bpy.types.Operator, tool.Ifc.Operator):
    bl_idname = "bim.unassign_group"
@@ -56,6 +56,7 @@ classes = (
    operator.RemoveMaterial,
    operator.RemoveMaterialSet,
    operator.RemoveProfile,
+    operator.RenameMaterial,
    operator.ReorderMaterialSetItem,
    operator.SelectByMaterial,
    operator.SelectMaterialInMaterialsUI,
@@ -102,6 +102,26 @@ class EditMaterial(bpy.types.Operator, tool.Ifc.Operator):
        core.edit_material(tool.Ifc, tool.Material, material=tool.Ifc.get().by_id(self.material))


+class RenameMaterial(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.rename_material"
+    bl_label = "Rename Material"
+    bl_description = "Rename an IfcMaterial"
+    bl_options = {"REGISTER", "UNDO"}
+    material: bpy.props.IntProperty()
+    name: bpy.props.StringProperty(name="Name")
+
+    def invoke(self, context, event):
+        material = tool.Ifc.get().by_id(self.material)
+        self.name = material.Name or ""
+        return context.window_manager.invoke_props_dialog(self)
+
+    def draw(self, context):
+        self.layout.prop(self, "name")
+
+    def _execute(self, context):
+        core.rename_material(tool.Ifc, tool.Material, material=tool.Ifc.get().by_id(self.material), name=self.name)
+
+
 class DisableEditingMaterial(bpy.types.Operator):
    bl_idname = "bim.disable_editing_material"
    bl_label = "Disable Editing Material"
@@ -93,6 +93,30 @@ def _stroke_lines_alpha(
    gpu.state.blend_set("NONE")


+def _connected_components(
+    vertex_groups: dict[int, list[bmesh.types.BMVert]],
+) -> list[list[bmesh.types.BMVert]]:
+    """Split each vertex group's members into their connected components,
+    since a duplicated arc/circle loop shares its source loop's group index."""
+    components = []
+    for verts in vertex_groups.values():
+        remaining = set(verts)
+        while remaining:
+            seed = remaining.pop()
+            stack = [seed]
+            component = [seed]
+            while stack:
+                v = stack.pop()
+                for edge in v.link_edges:
+                    other = edge.other_vert(v)
+                    if other in remaining:
+                        remaining.discard(other)
+                        stack.append(other)
+                        component.append(other)
+            components.append(component)
+    return components
+
+
 class ProfileDecorator:
    installed = None

@@ -265,7 +289,7 @@ class ProfileDecorator:
        # Draw arcs
        arc_centroids = []
        arc_segments = []
-        for arc in arcs.values():
+        for arc in _connected_components(arcs):
            if len(arc) != 3:
                continue
            sorted_arc = [None, None, None]
@@ -292,7 +316,7 @@ class ProfileDecorator:
        # Draw circles
        circle_centroids = []
        circle_segments = []
-        for circle in circles.values():
+        for circle in _connected_components(circles):
            if len(circle) != 2:
                continue
            p1 = obj.matrix_world @ circle[0].co
@@ -162,7 +162,7 @@ class ProjectLibraryData:
        library_file = IfcStore.library_file
        if library_file is None or library_file.schema == "IFC2X3":
            return results
-        root = tool.Project.get_root_context(library_file)
+        root = library_file.by_type("IfcProject")[0]
        results.append((str(root.id()), f"{root.is_a()} {root.Name or 'Unnamed'}", root.Description or ""))
        for library_id, data in cls.data["project_libraries"].items():
            results.append((str(library_id), data["Name"] or "Unnamed", data["Description"] or ""))
@@ -281,7 +281,7 @@ class RefreshLibrary(bpy.types.Operator):
        elements = {e for e in elements if not tool.Project.is_element_assigned_to_project_library(e, rels)}
        self.props.add_library_project_library("Unassigned", len(elements), 0, False)

-        root_context = tool.Project.get_root_context(library_file)
+        root_context = library_file.by_type("IfcProject")[0]
        hierarchy = tool.Project.get_project_hierarchy(library_file)
        tool.Project.load_project_libraries_to_ui(root_context, hierarchy)
        return {"FINISHED"}
@@ -761,21 +761,22 @@ class EditProjectLibrary(bpy.types.Operator):
        attributes = bonsai.bim.helper.export_attributes(props.project_library_attributes)
        ifcopenshell.api.attribute.edit_attributes(library_file, project_library, attributes)

-        # Update parent library.
+        # Update parent library. Tear down the old IfcRelDeclares/IfcRelNests before
+        # creating the new one; a library must have exactly one of the two, never both.
        previous_parent_library = tool.Project.get_parent_library(project_library)
        new_parent_library = library_file.by_id(int(props.parent_library))
        if previous_parent_library != new_parent_library:
-            if previous_parent_library is None:
-                # Edited library was a root in a library-only file; nest it under the new parent.
+            if previous_parent_library is not None:
+                if previous_parent_library.is_a("IfcProject"):
+                    ifcopenshell.api.project.unassign_declaration(
+                        library_file, [project_library], previous_parent_library
+                    )
+                else:
+                    ifcopenshell.api.nest.unassign_object(library_file, [project_library])
+            if new_parent_library.is_a("IfcProject"):
+                ifcopenshell.api.project.assign_declaration(library_file, [project_library], new_parent_library)
+            else:
                ifcopenshell.api.nest.assign_object(library_file, [project_library], new_parent_library)
-            elif previous_parent_library.is_a("IfcProject"):
-                # Then new one is IfcProjectLibrary.
-                ifcopenshell.api.nest.assign_object(library_file, [project_library], new_parent_library)
-            else:  # Previous is IfcProjectLibrary.
-                ifcopenshell.api.nest.unassign_object(library_file, [project_library])
-                # If new one is IfcProject, then it's already assigned by default.
-                if new_parent_library.is_a("IfcProjectLibrary"):
-                    ifcopenshell.api.nest.assign_object(library_file, [project_library], new_parent_library)

        props.is_editing_project_library = False
        bpy.ops.bim.refresh_library()
@@ -809,12 +810,9 @@ class AddProjectLibrary(bpy.types.Operator):
        props = tool.Project.get_project_props()
        library_file = IfcStore.library_file
        assert library_file
-        root_context = tool.Project.get_root_context(library_file)
+        root_context = library_file.by_type("IfcProject")[0]
        project_library = ifcopenshell.api.root.create_entity(library_file, "IfcProjectLibrary")
-        if root_context.is_a("IfcProject"):
-            ifcopenshell.api.project.assign_declaration(library_file, [project_library], root_context)
-        else:
-            ifcopenshell.api.nest.assign_object(library_file, [project_library], root_context)
+        ifcopenshell.api.project.assign_declaration(library_file, [project_library], root_context)
        ProjectLibraryData.load()  # Update enum.
        props.selected_project_library = str(project_library.id())
        props.is_editing_project_library = True
@@ -1301,6 +1299,10 @@ class LoadProjectElements(bpy.types.Operator):
        tool.Project.set_default_modeling_dimensions()
        tool.Root.reload_grid_decorator()
        bonsai.bim.handler.refresh_ui_data()
+        for screen in bpy.data.screens:
+            for area in screen.areas:
+                if area.type == "VIEW_3D":
+                    bonsai.bim.handler.viewport_shading_changed_callback(area)
        return {"FINISHED"}

    def get_decomposition_elements(self) -> set[ifcopenshell.entity_instance]:
@@ -1578,10 +1580,13 @@ class LoadLink(bpy.types.Operator, tool.Ifc.Operator):
        json_filepath = self.filepath_.with_suffix(".ifc.cache.json")

        def should_clear_cache() -> bool:
-            if not self.use_cache:
-                return True
+            # Nothing to clear if the cache file was never created (e.g. a
+            # fresh link). Check this first so os.remove below is never
+            # called on a non-existent path, regardless of use_cache.
            if not blend_filepath.exists():
                return False
+            if not self.use_cache:
+                return True
            data = json.loads(json_filepath.read_text())
            # Empty 'query' - model loaded without custom query.
            # Missing 'query' - model was loaded before custom queries were introduced in Bonsai.
@@ -104,7 +104,7 @@ def get_footing_length(o: bpy.types.Object) -> float:
        return get_length(o)
    if predefined_type == "FOOTING_BEAM" or predefined_type == "STRIP_FOOTING":
        return get_z(o)
-    elif predefined_type == "PAD_FOOTING":
+    elif predefined_type == "PAD_FOOTING" or predefined_type == "PILE_CAP":
        return max(get_x(o), get_y(o))
    else:
        return get_length(o)
@@ -197,12 +197,26 @@ def get_footing_height(o: bpy.types.Object) -> float:
        return get_height(o)
    if predefined_type == "FOOTING_BEAM" or predefined_type == "STRIP_FOOTING":
        return get_y(o)
-    elif predefined_type == "PAD_FOOTING":
+    elif predefined_type == "PAD_FOOTING" or predefined_type == "PILE_CAP":
        return get_z(o)
    else:
        return get_height(o)


+def get_footing_width(o: bpy.types.Object) -> float:
+    element = tool.Ifc.get_entity(o)
+    assert element
+    predefined_type = ifcopenshell.util.element.get_predefined_type(element)
+    if not predefined_type:
+        return get_width(o)
+    if predefined_type == "FOOTING_BEAM" or predefined_type == "STRIP_FOOTING":
+        return get_x(o)
+    elif predefined_type == "PAD_FOOTING" or predefined_type == "PILE_CAP":
+        return get_width(o)
+    else:
+        return get_width(o)
+
+
 def get_height(o: bpy.types.Object) -> float:
    """_summary_: Returns the height of the object bounding box

@@ -225,7 +239,7 @@ def get_opening_depth(obj: bpy.types.Object) -> float:
    if is_opening_horizontal(obj):
        return get_height(obj)
    else:
-        return get_width(obj)
+        return get_y(obj)


 def get_opening_mapping_area(obj: bpy.types.Object) -> float:
@@ -413,12 +413,13 @@ class UnlinkObject(bpy.types.Operator, tool.Ifc.Operator):
    skip_invoke: bpy.props.BoolProperty(default=False, options={"SKIP_SAVE"})

    def _execute(self, context):
+        objects: list[bpy.types.Object]
        if self.obj:
-            objects = [bpy.data.objects.get(self.obj)]
+            requested_obj = bpy.data.objects.get(self.obj)
+            objects = [requested_obj] if requested_obj is not None else []
        else:
            objects = context.selected_objects

-        objects: list[bpy.types.Object]
        for obj in objects:
            was_active_object = obj == context.active_object

@@ -132,5 +132,12 @@ class SelectSimilarData:
            if pset.endswith("Common"):
                keys.extend([f'/.*Common/."{name}"' for name in properties.keys() if name != "id"])
            else:
-                keys.extend([f"{pset}.{name}" for name in properties.keys() if name != "id"])
+                pset_part = f'"{pset}"' if " " in pset else pset
+                keys.extend(
+                    [
+                        f'{pset_part}."{name}"' if " " in name else f"{pset_part}.{name}"
+                        for name in properties.keys()
+                        if name != "id"
+                    ]
+                )
        return [(k, k, "") for k in keys]
@@ -12,7 +12,7 @@ function create_gantt_chart(json_data) {
        vShowTaskInfoLink: 1, // Show link in tool tip (0/1)
        vShowEndWeekDate: 0,  // Show/Hide the date for the last day of the week in header for daily
        vUseSingleCell: 10000, // Set the threshold cell per table row (Helps performance for large data.
-        vFormatArr: ['Day', 'Week', 'Month', 'Quarter'], // Even with setUseSingleCell using Hour format on such a large chart can cause issues in some browsers,
+        vFormatArr: ['Hour', 'Day', 'Week', 'Month', 'Quarter'], // vUseSingleCell keeps Hour usable on large charts.
        vShowRes: true, // 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.
@@ -45,6 +45,7 @@ class SpatialTool(WorkSpaceTool):
        ("bim.spatial_hotkey", {"type": "T", "value": "PRESS", "shift": True}, {"properties": [("hotkey", "S_T")]}),
        ("bim.spatial_hotkey", {"type": "G", "value": "PRESS", "shift": True}, {"properties": [("hotkey", "S_G")]}),
        ("bim.spatial_hotkey", {"type": "H", "value": "PRESS", "shift": True}, {"properties": [("hotkey", "S_H")]}),
+        ("bim.spatial_hotkey", {"type": "Q", "value": "PRESS", "shift": True}, {"properties": [("hotkey", "S_Q")]}),
    )

    def draw_settings(context, layout, ws_tool):
@@ -184,3 +185,9 @@ class Hotkey(bpy.types.Operator, tool.Ifc.Operator):

    def hotkey_S_G(self):
        bpy.ops.bim.generate_space()
+
+    def hotkey_S_Q(self):
+        # Mirrors BimTool.hotkey_S_Q so quantities can be (re)calculated without switching tools.
+        if not bpy.context.selected_objects:
+            return
+        bpy.ops.bim.perform_quantity_take_off()
@@ -45,7 +45,9 @@ classes = (
    operator.SelectByStyle,
    operator.SelectStyleInStylesUI,
    operator.SetAssetMaterialToExternalStyle,
+    operator.SuggestShadeFromExternalStyle,
    operator.UnlinkStyle,
+    operator.TogglePreferIfcShading,
    operator.UpdateCurrentStyle,
    operator.UpdateStyleColours,
    operator.UpdateStyleTextures,
@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.

+import colorsys
 import os
 from pathlib import Path
 from typing import Any, Union
@@ -238,13 +239,15 @@ class UpdateCurrentStyle(bpy.types.Operator):
            if not isinstance(obj.data, (bpy.types.Mesh, bpy.types.Curve)):
                continue
            for mat in obj.data.materials:
-                if (
-                    mat
-                    and mat not in updated_materials
-                    and (msprops_ := tool.Style.get_material_style_props(mat)).ifc_definition_id != 0
-                ):
-                    msprops_.active_style_type = current_style_type
-                    updated_materials.add(mat)
+                if not mat:
+                    continue
+                msprops_ = tool.Style.get_material_style_props(mat)
+                if msprops_.ifc_definition_id == 0:
+                    continue
+                if mat in updated_materials:
+                    continue
+                msprops_.active_style_type = current_style_type
+                updated_materials.add(mat)
        return {"FINISHED"}


@@ -457,10 +460,14 @@ class ActivateExternalStyle(bpy.types.Operator):
            self.report({"ERROR"}, f"Error loading external style for \"{material.name}\" - {db['msg']}")
            return {"CANCELLED"}

-        self.copy_material_attributes(db["data_block"], material)
+        ext_mat = db["data_block"]
+        self.copy_material_attributes(ext_mat, material)
        if tool.Style.get_use_nodes(material):
-            tool.Blender.copy_node_graph(material, db["data_block"])
-        bpy.data.materials.remove(db["data_block"])
+            if material.get("bim_dual_branch"):
+                tool.Style.update_external_branch(material, ext_mat)
+            else:
+                tool.Style.setup_dual_branch(material, ext_mat)
+        bpy.data.materials.remove(ext_mat)
        return {"FINISHED"}

    def copy_material_attributes(self, source, target):
@@ -503,6 +510,218 @@ class ActivateExternalStyle(bpy.types.Operator):
            set_prop(prop_name)


+class TogglePreferIfcShading(bpy.types.Operator):
+    bl_idname = "bim.toggle_prefer_ifc_shading"
+    bl_label = "Toggle Flat/Pretty"
+    bl_description = (
+        "Toggle between Flat (IFC-native shading) and Pretty (external .blend style) for ALL styles.\n\n"
+        "SHIFT+CLICK to apply to this style only"
+    )
+    bl_options = {"REGISTER", "UNDO"}
+    material_name: bpy.props.StringProperty(name="Material Name", default="", options={"SKIP_SAVE"})
+    single_only: bpy.props.BoolProperty(name="Single Only", default=False, options={"SKIP_SAVE"})
+
+    def invoke(self, context, event):
+        if event.shift:
+            self.single_only = True
+        return self.execute(context)
+
+    def execute(self, context):
+        wm = context.window_manager
+        space = tool.Blender.get_view3d_space()
+        is_solid = space and space.shading.type == "SOLID"
+
+        if is_solid:
+            if space.shading.color_type == "TEXTURE":
+                space.shading.color_type = "MATERIAL"
+            else:
+                meshes_needing_uv = []
+                for obj in bpy.context.scene.objects:
+                    if not isinstance(obj.data, bpy.types.Mesh):
+                        continue
+                    for slot in obj.material_slots:
+                        mat = slot.material
+                        if not mat or not tool.Blender.get_ifc_definition_id(mat):
+                            continue
+                        style_elements = tool.Style.get_style_elements(mat)
+                        if style_elements.get("IfcSurfaceStyleWithTextures") and not obj.data.uv_layers:
+                            meshes_needing_uv.append(obj.data)
+                            break
+                wm.progress_begin(0, max(len(meshes_needing_uv), 1))
+                try:
+                    for i, mesh in enumerate(meshes_needing_uv):
+                        tool.Loader.load_generated_uv_map(mesh)
+                        wm.progress_update(i)
+                finally:
+                    wm.progress_end()
+                space.shading.color_type = "TEXTURE"
+            return {"FINISHED"}
+
+        if self.single_only:
+            mat = bpy.data.materials.get(self.material_name)
+            if not mat:
+                return {"CANCELLED"}
+            msprops = tool.Style.get_material_style_props(mat)
+            msprops.prefer_ifc_shading = not msprops.prefer_ifc_shading
+        else:
+            # Default: apply to all IFC materials
+            source_mat = bpy.data.materials.get(self.material_name)
+            new_value = not tool.Style.get_material_style_props(source_mat).prefer_ifc_shading if source_mat else True
+            ifc_mats = [m for m in bpy.data.materials if tool.Blender.get_ifc_definition_id(m)]
+            for mat in ifc_mats:
+                tool.Style.get_material_style_props(mat).prefer_ifc_shading = new_value
+        return {"FINISHED"}
+
+
+class SuggestShadeFromExternalStyle(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.suggest_shade_from_external_style"
+    bl_label = "Suggest Shade from External Style"
+    bl_description = (
+        "Generate a Shade style (Surface Colour + Transparency) from the external .blend style.\n\n"
+        "ALT+CLICK to apply to all styles with an external .blend style"
+    )
+    bl_options = {"REGISTER", "UNDO"}
+    material_name: bpy.props.StringProperty(name="Material Name", default="", options={"SKIP_SAVE"})
+    all_styles: bpy.props.BoolProperty(name="All Styles", default=False, options={"SKIP_SAVE"})
+    value_offset: bpy.props.FloatProperty(
+        name="Value",
+        description="Offset added to the colour's value (-1 = fully dark, 0 = unchanged, +1 = fully light)",
+        default=0.0,
+        min=-1.0,
+        max=1.0,
+        step=1,
+        precision=2,
+        options={"SKIP_SAVE"},
+    )
+    saturation_factor: bpy.props.FloatProperty(
+        name="Saturation",
+        description="Scale applied to the colour's saturation (0 = greyscale, 1 = unchanged, >1 = more saturated)",
+        default=1.0,
+        min=0.0,
+        max=2.0,
+        step=1,
+        precision=2,
+        options={"SKIP_SAVE"},
+    )
+
+    def invoke(self, context, event):
+        if event.alt:
+            self.all_styles = True
+        return context.window_manager.invoke_props_dialog(self)
+
+    def draw(self, context):
+        layout = self.layout
+        layout.prop(self, "value_offset", slider=True)
+        layout.prop(self, "saturation_factor", slider=True)
+        if self.all_styles:
+            layout.label(text="Will apply to all external styles", icon="INFO")
+
+    def _execute(self, context):
+        if self.all_styles:
+            candidates = [
+                (mat, tool.Style.get_style_elements(mat))
+                for mat in bpy.data.materials
+                if tool.Blender.get_ifc_definition_id(mat)
+            ]
+            candidates = [(mat, se) for mat, se in candidates if tool.Style.has_blender_external_style(se)]
+            wm = context.window_manager
+            wm.progress_begin(0, max(len(candidates), 1))
+            count = 0
+            color_cache: dict[tuple[str, str, str], tuple | None] = {}
+            try:
+                for i, (mat, style_elements) in enumerate(candidates):
+                    wm.progress_update(i)
+                    if self._apply_to_material(
+                        mat, style_elements, self.value_offset, self.saturation_factor, color_cache
+                    ):
+                        count += 1
+            finally:
+                wm.progress_end()
+            self.report({"INFO"}, f"Shade style generated for {count} style(s).")
+        else:
+            mat = bpy.data.materials.get(self.material_name)
+            if not mat:
+                return {"CANCELLED"}
+            style_elements = tool.Style.get_style_elements(mat)
+            if not tool.Style.has_blender_external_style(style_elements):
+                self.report({"ERROR"}, "No external .blend style assigned. Please assign an external style first.")
+                return {"CANCELLED"}
+            self._apply_to_material(mat, style_elements, self.value_offset, self.saturation_factor)
+        props = tool.Style.get_style_props()
+        if props.is_editing:
+            core.load_styles(tool.Style, style_type=props.style_type)
+
+    def _apply_to_material(
+        self,
+        material: bpy.types.Material,
+        style_elements: dict,
+        value_offset: float = 0.0,
+        saturation_factor: float = 1.0,
+        color_cache: "dict[tuple[str, str, str], tuple | None] | None" = None,
+    ) -> bool:
+        external_style = style_elements["IfcExternallyDefinedSurfaceStyle"]
+        style_path = Path(tool.Ifc.resolve_uri(external_style.Location))
+        data_block_type, data_block = external_style.Identification.split("/")
+
+        cache_key = (str(style_path), data_block_type, data_block)
+        if color_cache is not None and cache_key in color_cache:
+            cached = color_cache[cache_key]
+            if cached is None:
+                return False  # previously failed for this path
+            surface_colour, transparency = cached
+        else:
+            try:
+                db = tool.Blender.append_data_block(str(style_path), data_block_type, data_block)
+            except OSError as e:
+                self.report({"WARNING"}, f'Could not open blend file for "{material.name}": {e}')
+                if color_cache is not None:
+                    color_cache[cache_key] = None
+                return False
+            if not db["data_block"]:
+                self.report({"WARNING"}, f'Could not load external style for "{material.name}": {db["msg"]}')
+                if color_cache is not None:
+                    color_cache[cache_key] = None
+                return False
+
+            ext_mat = db["data_block"]
+            surface_colour, transparency = tool.Style.get_representative_material_color(ext_mat)
+            bpy.data.materials.remove(ext_mat)
+            if color_cache is not None:
+                color_cache[cache_key] = (surface_colour, transparency)
+
+        if value_offset != 0.0 or saturation_factor != 1.0:
+            h, s, v = colorsys.rgb_to_hsv(*surface_colour)
+            v = max(0.0, min(1.0, v + value_offset))
+            s = max(0.0, min(1.0, s * saturation_factor))
+            surface_colour = colorsys.hsv_to_rgb(h, s, v)
+
+        ifc_style = tool.Ifc.get_entity(material)
+        attributes: dict = {
+            "SurfaceColour": {
+                "Name": None,
+                "Red": surface_colour[0],
+                "Green": surface_colour[1],
+                "Blue": surface_colour[2],
+            },
+        }
+        if tool.Ifc.get_schema() != "IFC2X3":
+            attributes["Transparency"] = transparency
+
+        shading_style = style_elements.get("IfcSurfaceStyleShading")
+        if shading_style:
+            tool.Ifc.run("style.edit_surface_style", style=shading_style, attributes=attributes)
+        else:
+            tool.Ifc.run(
+                "style.add_surface_style",
+                style=ifc_style,
+                ifc_class="IfcSurfaceStyleShading",
+                attributes=attributes,
+            )
+        material.diffuse_color = (*surface_colour, 1.0 - transparency)
+        tool.Style.sync_flat_branch_shading(material, surface_colour, transparency)
+        return True
+
+
 class DisableEditingStyles(bpy.types.Operator):
    bl_idname = "bim.disable_editing_styles"
    bl_options = {"REGISTER", "UNDO"}
@@ -372,6 +372,16 @@ def update_shading_style(self: "BIMStyleProperties", context: bpy.types.Context)
        tool.Style.switch_shading(blender_material, self.active_style_type)


+def update_prefer_ifc_shading(self: "BIMStyleProperties", context: bpy.types.Context) -> None:
+    style_elements = tool.Style.get_style_elements(self.id_data)
+    has_external = tool.Style.has_blender_external_style(style_elements)
+    if self.prefer_ifc_shading or not has_external:
+        self.active_style_type = "Shading"
+    else:
+        self.active_style_type = "External"
+    self.id_data.update_tag()
+
+
 class BIMStyleProperties(PropertyGroup):
    ifc_definition_id: IntProperty(name="IFC Definition ID")
    active_style_type: EnumProperty(
@@ -381,9 +391,19 @@ class BIMStyleProperties(PropertyGroup):
        default="Shading",
        update=update_shading_style,
    )
+    prefer_ifc_shading: BoolProperty(
+        name="Flat / Pretty",
+        description=(
+            "Toggle between Flat (IFC-native shading) and Pretty (external .blend style). "
+            "When set to Flat, viewport switches to Material Preview or Rendered will not activate the external style."
+        ),
+        default=False,
+        update=update_prefer_ifc_shading,
+    )
    is_renaming: BoolProperty(description="Used to prevent triggering handler callback.", default=False)

    if TYPE_CHECKING:
        ifc_definition_id: int
        active_style_type: tool.Style.StyleType
+        prefer_ifc_shading: bool
        is_renaming: bool
@@ -110,6 +110,11 @@ class BIM_PT_styles(Panel):
                op = row.operator("bim.update_current_style", icon="FILE_REFRESH", text="")
                op.style_id = style.ifc_definition_id

+            if active_style and self.props.style_type == "IfcSurfaceStyle":
+                if material := style.blender_material:
+                    msprops = tool.Style.get_material_style_props(material)
+                    self.draw_style_status_row(material, msprops)
+
            if self.props.style_type == "IfcSurfaceStyle":
                self.layout.label(text="Surface Style Element:")
                col = self.layout.column(align=True)
@@ -161,6 +166,66 @@ class BIM_PT_styles(Panel):
                edit_label = "Save Lighting Style"
            self.draw_edit_ui(edit_label)

+    def draw_style_status_row(self, material: bpy.types.Material, msprops) -> None:
+        space = tool.Blender.get_view3d_space()
+        box = self.layout.box()
+
+        obj = bpy.context.active_object
+
+        parts = []
+        if space:
+            shading_type = space.shading.type
+            shading_labels = {
+                "SOLID": "Solid",
+                "MATERIAL": "Material Preview",
+                "RENDERED": "Rendered",
+                "WIREFRAME": "Wireframe",
+            }
+            parts.append(f"Viewport: {shading_labels.get(shading_type, shading_type)}")
+        else:
+            parts.append("No 3D viewport")
+            shading_type = None
+
+        if obj:
+            obj_has_uv = isinstance(obj.data, bpy.types.Mesh) and bool(obj.data.uv_layers)
+            uv_label = "UV \u2713" if obj_has_uv else "UV \u2717"
+            parts.append(f"Selected Object: {obj.name} {uv_label}")
+        else:
+            parts.append("Selected Object: None")
+
+        if shading_type == "SOLID":
+            is_flat = space.shading.color_type != "TEXTURE"
+            mode_label = "Flat"
+            dep_label = "Shade"
+            if not is_flat:
+                mode_label = "Pretty"
+                dep_label = "Texture \u2192 Shade"
+        elif shading_type in ("MATERIAL", "RENDERED"):
+            is_flat = msprops.prefer_ifc_shading
+            mode_label = "Flat"
+            dep_label = "Render+Texture \u2192 Render \u2192 Shade"
+            if not is_flat:
+                mode_label = "Pretty"
+                dep_label = "External \u2192 Render+Texture \u2192 Render \u2192 Shade"
+        else:
+            is_flat = False
+            mode_label = ""
+            dep_label = ""
+
+        row1 = box.row(align=True)
+        row1.label(text=" | ".join(parts))
+
+        if mode_label:
+            row2 = box.row(align=True)
+            row2.label(text=f"Current Mode: {mode_label} \u2014 {dep_label}")
+
+        row3 = box.row(align=True)
+        row3.alignment = "RIGHT"
+        op = row3.operator("bim.suggest_shade_from_external_style", text="", icon="BRUSHES_ALL")
+        op.material_name = material.name
+        op = row3.operator("bim.toggle_prefer_ifc_shading", text="", icon="UV_SYNC_SELECT")
+        op.material_name = material.name
+
    def draw_surface_style_shading(self):
        row = self.layout.row()
        row.prop(self.props, "surface_colour")
@@ -117,9 +117,7 @@ class UnassignType(bpy.types.Operator, tool.Ifc.Operator):
        related_object: str

    @staticmethod
-    def _reattach_styles(
-        file: ifcopenshell.file, copied_entities: dict[int, ifcopenshell.entity_instance]
-    ) -> None:
+    def _reattach_styles(file: ifcopenshell.file, copied_entities: dict[int, ifcopenshell.entity_instance]) -> None:
        """copy_deep only follows forward references, so IfcStyledItem (an inverse,
        ``StyledByItem``) is not carried onto the copied geometry. Re-create a
        styled item on each copy that points at the same presentation styles as
@@ -41,6 +41,7 @@ import bonsai.bim.helper
 import bonsai.tool as tool
 from bonsai.bim.ifc import is_cache_locked_by_other_process
 from bonsai.bim.module.bsdd.prop import BIMBSDDProperties, BSDDProperty
+from bonsai.bim.module.material.operator import SelectByMaterial
 from bonsai.bim.module.model import prop as _model_prop
 from bonsai.bim.module.model import ui as _model_ui
 from bonsai.bim.module.pset.prop import IfcProperty
@@ -1854,6 +1855,21 @@ def draw_statusbar(self, context):

 def draw_custom_context_menu(self: bpy.types.Menu, context: bpy.types.Context) -> None:
    # https://blender.stackexchange.com/a/275555/86891
+
+    # Context menu for material name buttons (e.g. `bim.select_by_material`),
+    # offering a quick "Rename Material" entry instead of having to look up
+    # the material in the scene Materials panel to rename it.
+    button_operator = getattr(context, "button_operator", None)
+    if button_operator is not None and button_operator.bl_rna.identifier == SelectByMaterial.bl_rna.identifier:
+        ifc_file = tool.Ifc.get()
+        material = ifc_file.by_id(button_operator.material) if ifc_file else None
+        if material is not None and material.is_a("IfcMaterial"):
+            assert self.layout
+            self.layout.separator()
+            op = self.layout.operator("bim.rename_material", text="Rename Material", icon="GREASEPENCIL")
+            op.material = material.id()
+        return
+
    if (
        not hasattr(context, "button_pointer")
        or not hasattr(context, "button_prop")
@@ -411,6 +411,37 @@ def duplicate_drawing(
    return new_drawing


+def copy_annotations_to_drawing(
+    ifc: type[tool.Ifc],
+    collector: type[tool.Collector],
+    drawing_tool: type[tool.Drawing],
+    geometry: type[tool.Geometry],
+    annotations: list[ifcopenshell.entity_instance],
+    target_drawing: ifcopenshell.entity_instance,
+) -> list[ifcopenshell.entity_instance]:
+    """Duplicate annotations into another drawing, leaving the originals untouched."""
+    target_group = drawing_tool.get_drawing_group(target_drawing)
+    if not target_group:
+        return []
+    annotations = [a for a in annotations if drawing_tool.get_annotation_drawing(a) != target_drawing]
+    annotation_objs = [obj for a in annotations if (obj := ifc.get_object(a))]
+    if not annotation_objs:
+        return []
+    camera = ifc.get_object(target_drawing) or drawing_tool.import_drawing(target_drawing)
+    old_to_new, _ = geometry.duplicate_ifc_objects(annotation_objs)
+    copied: list[ifcopenshell.entity_instance] = []
+    for new_elements in old_to_new.values():
+        for new_element in new_elements:
+            if old_group := drawing_tool.get_drawing_group(new_element):
+                ifc.run("group.unassign_group", group=old_group, products=[new_element])
+            ifc.run("group.assign_group", group=target_group, products=[new_element])
+            new_obj = ifc.get_object(new_element)
+            drawing_tool.ensure_annotation_in_drawing_plane(new_obj, camera)
+            collector.assign(new_obj, should_clean_users_collection=True)
+            copied.append(new_element)
+    return copied
+
+
 def remove_drawing(
    ifc: type[tool.Ifc], drawing_tool: type[tool.Drawing], drawing: ifcopenshell.entity_instance
 ) -> None:
@@ -107,6 +107,15 @@ def disable_editing_material(material_tool: type[tool.Material]) -> None:
    material_tool.disable_editing_material()


+def rename_material(
+    ifc: type[tool.Ifc], material_tool: type[tool.Material], material: ifcopenshell.entity_instance, name: str
+) -> None:
+    ifc.run("material.edit_material", material=material, attributes={"Name": name})
+    if material_tool.is_editing_materials():
+        material_tool.import_material_definitions(material_tool.get_active_material_type())
+    material_tool.refresh()
+
+
 def assign_material(
    ifc: type[tool.Ifc],
    material_tool: type[tool.Material],
@@ -354,6 +354,7 @@ class Drawing:
    def enable_editing_schedules(cls): pass
    def enable_editing_sheets(cls): pass
    def enable_editing_text(cls, obj): pass
+    def ensure_annotation_in_drawing_plane(cls, obj, camera=None): pass
    def ensure_drawings_parent_document(cls): pass
    def ensure_drawings_parent_group(cls): pass
    def ensure_unique_drawing_name(cls, name): pass
@@ -367,6 +368,7 @@ class Drawing:
    def generate_reference_attributes(cls, reference, **attributes): pass
    def generate_sheet_identification(cls): pass
    def get_annotation_context(cls, target_view, object_type=None): pass
+    def get_annotation_drawing(cls, element): pass
    def get_annotation_representation(cls, element_type): pass
    def get_assigned_product(cls, element): pass
    def get_assigned_product_workaround(cls, element): pass
@@ -384,6 +386,7 @@ class Drawing:
    def get_drawing_group(cls, drawing): pass
    def get_drawing_references(cls, drawing): pass
    def get_drawing_target_view(cls, drawing): pass
+    def get_group_drawing(cls, group): pass
    def get_group_elements(cls, group): pass
    def get_ifc_representation_class(cls, object_type): pass
    def get_name(cls, element): pass
@@ -397,6 +400,7 @@ class Drawing:
    def get_unit_system(cls): pass
    def import_assigned_product(cls, obj): pass
    def import_documents(cls, document_type): pass
+    def import_drawing(cls, drawing): pass
    def import_drawings(cls): pass
    def import_sheets(cls): pass
    def import_text_attributes(cls, obj): pass
@@ -663,6 +667,7 @@ class Material:
    def is_editing_materials(cls): pass
    def is_material_used_in_sets(cls, material): pass
    def load_material_attributes(cls, material): pass
+    def refresh(cls): pass
    def replace_material_with_material_profile(cls, element): pass
    def update_elements_using_material(cls, material): pass

@@ -803,6 +803,40 @@ class Blender(bonsai.core.tool.Blender):
        # restore shader editor settings
        shader_editor.pin = previous_pin_setting

+    @classmethod
+    def copy_node_graph_additive(
+        cls, material_to: bpy.types.Material, material_from: bpy.types.Material
+    ) -> bpy.types.ShaderNodeOutputMaterial | None:
+        """Paste nodes from material_from alongside the existing nodes in material_to.
+
+        Unlike copy_node_graph this does NOT clear the existing node tree first.
+        Returns the OUTPUT_MATERIAL node that was added from material_from, or None.
+        """
+        temp_override = cls.get_shader_editor_context()
+        shader_editor = temp_override["space"]
+
+        before_names = {n.name for n in material_to.node_tree.nodes}
+
+        previous_pin_setting = shader_editor.pin
+        shader_editor.pin = True
+        shader_editor.node_tree = material_from.node_tree
+
+        for node in material_from.node_tree.nodes:
+            node.select = True
+        with bpy.context.temp_override(**temp_override):
+            bpy.ops.node.clipboard_copy()
+
+        shader_editor.node_tree = material_to.node_tree
+        with bpy.context.temp_override(**temp_override):
+            bpy.ops.node.clipboard_paste(offset=(0, 0))
+
+        shader_editor.pin = previous_pin_setting
+
+        for node in material_to.node_tree.nodes:
+            if node.name not in before_names and node.type == "OUTPUT_MATERIAL":
+                return node
+        return None
+
    @classmethod
    def get_material_node(
        cls, blender_material: bpy.types.Material, node_type: str, kwargs: Optional[dict] = {}
@@ -138,7 +138,6 @@ class Bsdd(bonsai.core.tool.Bsdd):
    def get_dictionaries(cls) -> list[bsdd.DictionaryContractV1]:
        prefs = tool.Blender.get_addon_preferences()
        baseurl = getattr(prefs, "bsdd_baseurl", "https://api.bsdd.buildingsmart.org/api/")
-        cls.client = bsdd.Client()
        if hasattr(cls.client, "baseurl"):
            cls.client.baseurl = baseurl
        response = cls.client.get_dictionary(include_test_dictionaries=prefs.bsdd_load_test_dictionaries)
@@ -1270,6 +1270,17 @@ class ClipBox:
    def on_depsgraph_update_caps(cls, scene, depsgraph) -> None:
        """Depsgraph entry-point — guard, then delegate to the
        modal-aware debounce in :meth:`_handle_cap_tick`."""
+        # Same file-load danger window as on_depsgraph_update: a real
+        # depsgraph tick during load (between load_pre and the new file's
+        # first paint) must not re-arm a cap-rebuild timer. _on_load_pre
+        # already cancels any in-flight timer via _cancel_pending_cap_rebuild;
+        # without this gate, a depsgraph_update_post event firing later in
+        # the same load (Blender fires these while building the new file's
+        # scene) would immediately reschedule one via _handle_cap_tick,
+        # undoing that cancellation and re-arming against regions whose GPU
+        # state is not yet wired.
+        if cls._file_loading:
+            return
        if getattr(bpy.context, "screen", None) is None:
            return
        if cls._active_scene_props(scene) is None:
@@ -756,6 +756,17 @@ class Drawing(bonsai.core.tool.Drawing):
            if rel.is_a("IfcRelAssignsToGroup") and rel.RelatingGroup.ObjectType == "DRAWING":
                return rel.RelatingGroup

+    @classmethod
+    def get_group_drawing(cls, group: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
+        """Get the drawing that owns this group, if the group represents a drawing."""
+        if group.ObjectType != "DRAWING":
+            return None
+        for rel in group.IsGroupedBy or []:
+            for related_object in rel.RelatedObjects:
+                if related_object.is_a("IfcAnnotation") and related_object.ObjectType == "DRAWING":
+                    return related_object
+        return None
+
    @classmethod
    def get_drawing_document(cls, drawing: ifcopenshell.entity_instance) -> ifcopenshell.entity_instance:
        for rel in drawing.HasAssociations:
@@ -2876,6 +2887,50 @@ class Drawing(bonsai.core.tool.Drawing):
                    break
        return sheet_references

+    @classmethod
+    def get_sheeted_drawing_ids(cls) -> set[int]:
+        """Get the IFC ids of all drawings that are placed on at least one sheet."""
+        ifc_file = tool.Ifc.get()
+        sheet_locations: set[Union[str, None]] = set()
+        for sheet in ifc_file.by_type("IfcDocumentInformation"):
+            if sheet.Scope != "SHEET":
+                continue
+            for reference in cls.get_document_references(sheet):
+                sheet_locations.add(reference.Location)
+        if not sheet_locations:
+            return set()
+        result: set[int] = set()
+        for drawing in ifc_file.by_type("IfcAnnotation"):
+            if drawing.ObjectType != "DRAWING":
+                continue
+            drawing_document = cls.get_drawing_document(drawing)
+            if drawing_document and drawing_document.Location in sheet_locations:
+                result.add(drawing.id())
+        return result
+
+    @classmethod
+    def get_visible_drawings_in_category(cls, target_view: str) -> list[DrawingProperties]:
+        """Get the drawing items in a target view category that are currently visible in the drawing list.
+
+        Grouping is positional: individual drawing items don't carry their own ``target_view``, they belong to
+        the most recent header item above them. Only expanded categories contribute drawing items to the
+        collection, so a collapsed category yields an empty list. Respects the ``show_drawings_on_sheets_only``
+        filter so that select-all only affects visible drawings.
+        """
+        props = cls.get_document_props()
+        drawings: list[DrawingProperties] = []
+        in_category = False
+        for item in props.drawings:
+            if not item.is_drawing:
+                # Header row: we're inside the requested category until the next header.
+                in_category = item.target_view == target_view
+            elif in_category:
+                drawings.append(item)
+        if props.show_drawings_on_sheets_only:
+            sheeted_ids = cls.get_sheeted_drawing_ids()
+            drawings = [d for d in drawings if d.ifc_definition_id in sheeted_ids]
+        return drawings
+
    @classmethod
    def get_camera_matrix(cls, camera: bpy.types.Object) -> Matrix:
        matrix_world = camera.matrix_world.copy().normalized()
@@ -1151,6 +1151,9 @@ class Geometry(bonsai.core.tool.Geometry):
        settings.set("layerset-first", True)
        settings.set("keep-bounding-boxes", True)
        settings.set("dimensionality", ifcopenshell.ifcopenshell_wrapper.CURVES_SURFACES_AND_SOLIDS)
+        settings.set("mesher-linear-deflection", ifc_import_settings.deflection_tolerance)
+        settings.set("mesher-angular-deflection", ifc_import_settings.angular_tolerance)
+        geometry_library = ifc_import_settings.geometry_library

        ifc_importer = bonsai.bim.import_ifc.IfcImporter(ifc_import_settings)
        ifc_importer.file = tool.Ifc.get()
@@ -1162,7 +1165,11 @@ class Geometry(bonsai.core.tool.Geometry):
        shape = None
        if elements:
            iterator = ifcopenshell.geom.iterator(
-                settings, tool.Ifc.get(), multiprocessing.cpu_count(), include=elements
+                settings,
+                tool.Ifc.get(),
+                multiprocessing.cpu_count(),
+                include=elements,
+                geometry_library=geometry_library,
            )
        else:
            iterator = None  # For example, when switching representation of a type with no occurrences
@@ -1217,7 +1224,9 @@ class Geometry(bonsai.core.tool.Geometry):
        for element in element_types:
            if obj := tool.Ifc.get_object(element):
                if representation := ifcopenshell.util.representation.get_representation(element, context):
-                    geometry = ifcopenshell.geom.create_shape(settings, representation)
+                    geometry = ifcopenshell.geom.create_shape(
+                        settings, representation, geometry_library=geometry_library
+                    )
                    mesh_name = tool.Loader.get_mesh_name_from_shape(geometry)
                    mesh = meshes.get(mesh_name)
                    if mesh is None:
@@ -146,6 +146,12 @@ class Material(bonsai.core.tool.Material):

        MaterialsData.data["material_styles_data"] = MaterialsData.material_styles_data()

+    @classmethod
+    def refresh(cls) -> None:
+        from bonsai.bim.module.material.data import refresh as refresh_material_data
+
+        refresh_material_data()
+
    @classmethod
    def is_editing_materials(cls) -> bool:
        props = tool.Material.get_material_props()
@@ -2292,32 +2292,18 @@ class Model(bonsai.core.tool.Model):
        deform_layer = bm.verts.layers.deform.active

        # Sanity check
-        group_verts = {"IFCARCINDEX": {}, "IFCCIRCLE": {}}
        if deform_layer:
            for vert in bm.verts:
                vert_group_indices = tool.Blender.bmesh_get_vertex_groups(vert, deform_layer)
-                is_circle = False
-                for group_index in vert_group_indices:
-                    group_type = "IFCARCINDEX" if group_index in groups["IFCARCINDEX"] else "IFCCIRCLE"
-                    group_verts[group_type].setdefault(group_index, 0)
-                    group_verts[group_type][group_index] += 1
-                    if group_type == "IFCCIRCLE":
-                        is_circle = True
+                is_circle = any(gi in groups["IFCCIRCLE"] for gi in vert_group_indices)
+                is_arc = any(gi in groups["IFCARCINDEX"] for gi in vert_group_indices)
+                if (is_circle or is_arc) and not vert.link_edges:
+                    return (False, "CIRCLE" if is_circle else "3POINT_ARC")
                if is_circle:
                    pass  # Circles are allowed to be unclosed
                elif len(vert.link_edges) != 2:  # Unclosed loop or forked loop
                    return (False, "UNCLOSED_LOOP")

-        for group_type, group_counts in group_verts.items():
-            if group_type == "IFCARCINDEX":
-                for group_count in group_counts.values():
-                    if group_count != 3:  # Each arc needs 3 verts
-                        return (False, "3POINT_ARC")
-            elif group_type == "IFCCIRCLE":
-                for group_count in group_counts.values():
-                    if group_count != 2:  # Each circle needs 2 verts
-                        return (False, "CIRCLE")
-
        loop_edges = list(bm.edges)

        # Create loops from edges
@@ -2340,6 +2326,28 @@ class Model(bonsai.core.tool.Model):
                        has_found_connected_edge = True
            loops.append(loop)

+        # Sanity check, per loop rather than across the whole mesh
+        if deform_layer:
+            for loop in loops:
+                loop_group_counts = {"IFCARCINDEX": {}, "IFCCIRCLE": {}}
+                loop_verts = {v for edge in loop for v in edge.verts}
+                for vert in loop_verts:
+                    for group_index in tool.Blender.bmesh_get_vertex_groups(vert, deform_layer):
+                        if group_index in groups["IFCARCINDEX"]:
+                            group_type = "IFCARCINDEX"
+                        elif group_index in groups["IFCCIRCLE"]:
+                            group_type = "IFCCIRCLE"
+                        else:
+                            continue
+                        loop_group_counts[group_type].setdefault(group_index, 0)
+                        loop_group_counts[group_type][group_index] += 1
+                for group_count in loop_group_counts["IFCARCINDEX"].values():
+                    if group_count != 3:  # Each arc needs 3 verts
+                        return (False, "3POINT_ARC")
+                for group_count in loop_group_counts["IFCCIRCLE"].values():
+                    if group_count != 2:  # Each circle needs 2 verts
+                        return (False, "CIRCLE")
+
        tmp = ifcopenshell.file(schema=tool.Ifc.get().schema)

        def is_in_group(v: bmesh.types.BMVert, group_name: str) -> bool:
@@ -2520,27 +2528,11 @@ class Model(bonsai.core.tool.Model):
        deform_layer = bm.verts.layers.deform.active

        # Sanity check
-        group_verts = {"IFCARCINDEX": {}, "IFCCIRCLE": {}}
        if deform_layer:
            for vert in bm.verts:
-                vert_group_indices = tool.Blender.bmesh_get_vertex_groups(vert, deform_layer)
-                for group_index in vert_group_indices:
-                    group_type = "IFCARCINDEX" if group_index in groups["IFCARCINDEX"] else "IFCCIRCLE"
-                    group_verts[group_type].setdefault(group_index, 0)
-                    group_verts[group_type][group_index] += 1
                if len(vert.link_edges) > 2:  # Forked loop
                    return (False, "FORKED_LOOP")

-        for group_type, group_counts in group_verts.items():
-            if group_type == "IFCARCINDEX":
-                for group_count in group_counts.values():
-                    if group_count != 3:  # Each arc needs 3 verts
-                        return (False, "3POINT_ARC")
-            elif group_type == "IFCCIRCLE":
-                for group_count in group_counts.values():
-                    if group_count != 2:  # Each circle needs 2 verts
-                        return (False, "CIRCLE")
-
        loop_edges = list(bm.edges)

        # Create loops from edges
@@ -2563,6 +2555,28 @@ class Model(bonsai.core.tool.Model):
                        has_found_connected_edge = True
            loops.append(loop)

+        # Sanity check, per loop rather than across the whole mesh
+        if deform_layer:
+            for loop in loops:
+                loop_group_counts = {"IFCARCINDEX": {}, "IFCCIRCLE": {}}
+                loop_verts = {v for edge in loop for v in edge.verts}
+                for vert in loop_verts:
+                    for group_index in tool.Blender.bmesh_get_vertex_groups(vert, deform_layer):
+                        if group_index in groups["IFCARCINDEX"]:
+                            group_type = "IFCARCINDEX"
+                        elif group_index in groups["IFCCIRCLE"]:
+                            group_type = "IFCCIRCLE"
+                        else:
+                            continue
+                        loop_group_counts[group_type].setdefault(group_index, 0)
+                        loop_group_counts[group_type][group_index] += 1
+                for group_count in loop_group_counts["IFCARCINDEX"].values():
+                    if group_count != 3:  # Each arc needs 3 verts
+                        return (False, "3POINT_ARC")
+                for group_count in loop_group_counts["IFCCIRCLE"].values():
+                    if group_count != 2:  # Each circle needs 2 verts
+                        return (False, "CIRCLE")
+
        tmp = ifcopenshell.file(schema=tool.Ifc.get().schema)

        def is_in_group(v: bmesh.types.BMVert, group_name: str) -> bool:
@@ -47,7 +47,15 @@ class Nest(bonsai.core.tool.Nest):
            return False
        if relating_object == related_object:
            return False
-        is_compatible_class = relating_object.is_a("IfcElement") and related_object.is_a("IfcElement")
+        # IfcRelNests.RelatingObject/RelatedObjects are typed as the general
+        # IfcObjectDefinition, so nesting is schema-legal both between element
+        # occurrences (the common case, e.g. a faucet nested into a sink) and
+        # between element types (e.g. an assembly type nesting its component
+        # types). Mixing an occurrence with a type isn't a real modeling
+        # pattern, so only allow same-kind pairs. See #2283.
+        is_compatible_class = (relating_object.is_a("IfcElement") and related_object.is_a("IfcElement")) or (
+            relating_object.is_a("IfcTypeProduct") and related_object.is_a("IfcTypeProduct")
+        )
        if not is_compatible_class:
            return False
        # Prevent cyclic references: walk up the full hierarchy from the
@@ -168,12 +168,12 @@ class Polyline(bonsai.core.tool.Polyline):
        distance = (mouse_vector - last_point).length
        if distance < 0:
            return
-        angle, orientation_angle, angle_round_threshold = None, None
+        angle, orientation_angle = None, None
+        angle_round_threshold = 1000  # Avoids rounding when distance is too big
        if distance > 0:
            angle = tool.Cad.angle_3_vectors(
                second_to_last_point, last_point, mouse_vector, new_angle=None, degrees=True
            )
-            angle_round_threshold = 1000  # Avoids rounding when distance is too big

            # Round angle to the nearest 0.05
            angle = round(angle / 0.05) * 0.05 if distance < angle_round_threshold else angle
@@ -189,7 +189,7 @@ class Polyline(bonsai.core.tool.Polyline):
            angle = 0
            orientation_angle = 0
        if input_ui:
-            assert angle is not None and orientation_angle is not None and angle_round_threshold is not None
+            assert angle is not None and orientation_angle is not None
            if should_round:
                angle_snap = tool.Snap.get_angle_snap_value(context)
                angle = angle_snap * round(angle / angle_snap) if distance < angle_round_threshold else angle
@@ -391,29 +391,14 @@ class Project(bonsai.core.tool.Project):
    def get_parent_library(
        cls, project_library: ifcopenshell.entity_instance
    ) -> Union[ifcopenshell.entity_instance, None]:
-        """Return the IfcContext that declares or nests ``project_library``.
-
-        Returns ``None`` when ``project_library`` is itself the root of a
-        library-only file (no IfcRelNests, no IfcRelDeclares).
-        """
+        """Return the IfcContext that declares or nests ``project_library``, or ``None``
+        if neither relationship is present."""
        if nests := project_library.Nests:
            return nests[0].RelatingObject
        if has_context := project_library.HasContext:
            return has_context[0].RelatingContext
        return None

-    @classmethod
-    def get_root_context(cls, ifc_file: ifcopenshell.file) -> ifcopenshell.entity_instance:
-        """Return the file's root IfcContext.
-
-        Prefers IfcProject if present, otherwise falls back to IfcProjectLibrary —
-        library-only files are valid per IFC4+ and contain no IfcProject. Caller is
-        responsible for the IFC2X3 guard; IfcContext does not exist in that schema.
-        """
-        if projects := ifc_file.by_type("IfcProject"):
-            return projects[0]
-        return ifc_file.by_type("IfcProjectLibrary")[0]
-
    @classmethod
    def get_project_hierarchy(cls, ifc_file: ifcopenshell.file) -> HiearchyDict:
        """Get project hierarchy in the following form:
@@ -1159,11 +1159,11 @@ class Sequence(bonsai.core.tool.Sequence):
        props.task_input_colors.clear()
        for group, data in groups.items():
            for predefined_type in data["PredefinedType"]:
-                if group in ["CREATION", "OPERATION", "MOVEMENT_TO"]:
+                if group in ("CREATION", "OPERATION", "MOVEMENT_TO"):
                    predefined_type_item = props.task_output_colors.add()
-                elif group in ["MOVEMENT_FROM"]:
+                elif group in ("MOVEMENT_FROM",):
                    predefined_type_item = props.task_input_colors.add()
-                elif group in ["USERDEFINED", "DESTRUCTION"]:
+                elif group in ("USERDEFINED", "DESTRUCTION"):
                    predefined_type_item = props.task_input_colors.add()
                    predefined_type_item2 = props.task_output_colors.add()
                    predefined_type_item2.name = predefined_type
@@ -597,6 +597,146 @@ class Style(bonsai.core.tool.Style):
        external_style = style_elements.get("IfcExternallyDefinedSurfaceStyle", None)
        return bool(external_style and external_style.Location and external_style.Location.endswith(".blend"))

+    @classmethod
+    def _color_from_principled(cls, node: bpy.types.Node) -> tuple[tuple[float, float, float], float]:
+        color = cls._resolve_color_socket(node.inputs["Base Color"])
+        alpha_socket = node.inputs["Alpha"]
+        alpha_source = cls._upstream_color_source(alpha_socket)
+        if alpha_source and alpha_source[0] == "IMAGE":
+            pixels = alpha_source[1].pixels[:]
+            n = len(pixels) // 4
+            step = max(1, n // 4096)
+            a_sum = sum(pixels[i * 4 + 3] for i in range(0, n, step))
+            count = len(range(0, n, step)) or 1
+            transparency = 1.0 - (a_sum / count)
+        else:
+            transparency = 1.0 - alpha_socket.default_value
+        return color, transparency
+
+    @classmethod
+    def _color_from_shader_socket(
+        cls, socket: bpy.types.NodeSocket, seen: set[str] | None = None
+    ) -> tuple[tuple[float, float, float], float] | None:
+        if seen is None:
+            seen = set()
+        for link in socket.links:
+            node = link.from_node
+            if node.name in seen:
+                continue
+            seen.add(node.name)
+            if node.type == "BSDF_PRINCIPLED":
+                return cls._color_from_principled(node)
+            if node.type in ("BSDF_DIFFUSE", "DIFFUSE_BSDF"):
+                return cls._resolve_color_socket(node.inputs["Color"]), 0.0
+            if node.type == "BSDF_GLASS":
+                return cls._resolve_color_socket(node.inputs["Color"]), 0.0
+            if node.type in ("MIX_SHADER", "ADD_SHADER"):
+                for inp in node.inputs:
+                    if inp.type == "SHADER" and inp.is_linked:
+                        result = cls._color_from_shader_socket(inp, seen)
+                        if result:
+                            return result
+        return None
+
+    @classmethod
+    def get_representative_material_color(
+        cls, material: bpy.types.Material
+    ) -> tuple[tuple[float, float, float], float]:
+        if material.node_tree:
+            nodes = material.node_tree.nodes
+            output_node = next((n for n in nodes if n.type == "OUTPUT_MATERIAL" and n.is_active_output), None) or next(
+                (n for n in nodes if n.type == "OUTPUT_MATERIAL"), None
+            )
+            if output_node:
+                result = cls._color_from_shader_socket(output_node.inputs["Surface"])
+                if result:
+                    return result
+            # Fallback: scan all shader nodes if no output node or graph traversal found nothing
+            for node in nodes:
+                if node.type == "BSDF_PRINCIPLED":
+                    return cls._color_from_principled(node)
+            for node in nodes:
+                if node.type in ("BSDF_DIFFUSE", "DIFFUSE_BSDF"):
+                    return cls._resolve_color_socket(node.inputs["Color"]), 0.0
+            for node in nodes:
+                if node.type == "BSDF_GLASS":
+                    return cls._resolve_color_socket(node.inputs["Color"]), 0.0
+        color = tuple(material.diffuse_color[:3])
+        transparency = 1.0 - material.diffuse_color[3]
+        return color, transparency
+
+    @classmethod
+    def _collect_upstream_sources(cls, socket: bpy.types.NodeSocket, seen: set[str]) -> list[tuple[str, object]]:
+        """Recursively collect all upstream colour/image sources reachable from *socket*."""
+        results = []
+        for link in socket.links:
+            node = link.from_node
+            if node.name in seen:
+                continue
+            seen.add(node.name)
+            if node.type == "TEX_IMAGE":
+                results.append(("IMAGE", node.image))
+            elif node.type == "VALTORGB":
+                results.append(("COLORRAMP", node))
+            else:
+                for inp in node.inputs:
+                    if inp.is_linked:
+                        results.extend(cls._collect_upstream_sources(inp, seen))
+        return results
+
+    @classmethod
+    def _upstream_color_source(
+        cls, socket: bpy.types.NodeSocket, seen: set[str] | None = None
+    ) -> tuple[str, object] | None:
+        sources = cls._collect_upstream_sources(socket, set() if seen is None else seen)
+        # Prefer a concrete image texture over a colour ramp (which may be greyscale/procedural).
+        for s in sources:
+            if s[0] == "IMAGE":
+                return s
+        for s in sources:
+            if s[0] == "COLORRAMP":
+                return s
+        return None
+
+    @classmethod
+    def _resolve_color_socket(cls, socket: bpy.types.NodeSocket) -> tuple[float, float, float]:
+        source = cls._upstream_color_source(socket)
+        if source is None:
+            return tuple(socket.default_value[:3])
+        kind, obj = source
+        if kind == "IMAGE":
+            return cls._average_image_color(obj)
+        if kind == "COLORRAMP":
+            return cls._average_colorramp_color(obj)
+        return tuple(socket.default_value[:3])
+
+    @staticmethod
+    def _average_image_color(image: bpy.types.Image) -> tuple[float, float, float]:
+        pixels = image.pixels[:]
+        n = len(pixels) // 4
+        if n == 0:
+            return (0.5, 0.5, 0.5)
+        step = max(1, n // 4096)
+        r_sum = g_sum = b_sum = 0.0
+        count = 0
+        for i in range(0, n, step):
+            base = i * 4
+            r_sum += pixels[base]
+            g_sum += pixels[base + 1]
+            b_sum += pixels[base + 2]
+            count += 1
+        return (r_sum / count, g_sum / count, b_sum / count)
+
+    @staticmethod
+    def _average_colorramp_color(node: bpy.types.Node) -> tuple[float, float, float]:
+        elements = node.color_ramp.elements
+        if not elements:
+            return (0.5, 0.5, 0.5)
+        r = sum(e.color[0] for e in elements) / len(elements)
+        g = sum(e.color[1] for e in elements) / len(elements)
+        b = sum(e.color[2] for e in elements) / len(elements)
+        return (r, g, b)
+
    @classmethod
    def is_editing_styles(cls) -> bool:
        props = cls.get_style_props()
@@ -674,9 +814,179 @@ class Style(bonsai.core.tool.Style):
        props = cls.get_material_style_props(blender_material)
        props.active_style_type = props.active_style_type

+    @classmethod
+    def get_branch_outputs(
+        cls, material: bpy.types.Material
+    ) -> tuple[bpy.types.ShaderNode | None, bpy.types.ShaderNode | None]:
+        """Return (external_output_node, flat_output_node), or (None, None) if not dual-branch."""
+        if not material.node_tree:
+            return None, None
+        ext = material.node_tree.nodes.get("BIM_Output_External")
+        fast = material.node_tree.nodes.get("BIM_Output_Flat")
+        return ext, fast
+
+    @classmethod
+    def _remove_external_branch(cls, material: bpy.types.Material) -> None:
+        """Remove all nodes reachable from BIM_Output_External (walks links backwards)."""
+        if not material.node_tree:
+            return
+        nodes = material.node_tree.nodes
+        output = nodes.get("BIM_Output_External")
+        if not output:
+            return
+        to_remove: set[str] = set()
+        stack = [output]
+        while stack:
+            node = stack.pop()
+            if node.name in to_remove:
+                continue
+            to_remove.add(node.name)
+            for inp in node.inputs:
+                for link in inp.links:
+                    stack.append(link.from_node)
+        for name in list(to_remove):
+            n = nodes.get(name)
+            if n:
+                nodes.remove(n)
+
+    @classmethod
+    def _build_flat_branch_nodes(cls, material: bpy.types.Material) -> bpy.types.ShaderNode:
+        """Add a Principled BSDF flat-branch to material's existing node tree.
+
+        Reads IfcSurfaceStyleRendering or IfcSurfaceStyleShading from the linked IFC entity.
+        Defaults to a white BSDF when no IFC shading data is available.
+        Returns the new Material Output node (named BIM_Output_Flat, is_active_output=False).
+        """
+        from mathutils import Vector
+
+        style_elements = cls.get_style_elements(material)
+        nodes = material.node_tree.nodes
+        links = material.node_tree.links
+
+        bsdf = nodes.new("ShaderNodeBsdfPrincipled")
+        bsdf.location = Vector((10, -600))
+        output = nodes.new("ShaderNodeOutputMaterial")
+        output.name = "BIM_Output_Flat"
+        output.location = Vector((300, -600))
+        output.is_active_output = False
+        links.new(bsdf.outputs["BSDF"], output.inputs["Surface"])
+
+        rendering_style = None
+        shading_only = None
+        for surface_style in style_elements.values():
+            if surface_style.is_a() == "IfcSurfaceStyleShading":
+                shading_only = surface_style
+            elif surface_style.is_a("IfcSurfaceStyleRendering"):
+                rendering_style = surface_style
+                shading_only = None
+
+        if rendering_style:
+            d = tool.Loader.surface_style_to_dict(rendering_style)
+            if d.get("DiffuseColour"):
+                ctype, cval = d["DiffuseColour"]
+                if ctype == "IfcColourRgb":
+                    bsdf.inputs["Base Color"].default_value = cval + (1,)
+                    solid_color = cval
+                else:
+                    cval = tuple(v * cval for v in d["SurfaceColour"])
+                    bsdf.inputs["Base Color"].default_value = cval + (1,)
+                    solid_color = cval
+            else:
+                r, g, b = d["SurfaceColour"]
+                bsdf.inputs["Base Color"].default_value = (r, g, b, 1.0)
+                solid_color = (r, g, b)
+            if d.get("SpecularColour"):
+                ctype, cval = d["SpecularColour"]
+                if ctype == "IfcNormalisedRatioMeasure":
+                    bsdf.inputs["Metallic"].default_value = cval
+            if d.get("SpecularHighlight"):
+                bsdf.inputs["Roughness"].default_value = d["SpecularHighlight"]
+            transparency = d.get("Transparency") or 0.0
+            bsdf.inputs["Alpha"].default_value = 1 - transparency
+            if transparency > 0:
+                material.blend_method = "BLEND"
+            material.diffuse_color = solid_color + (1.0 - transparency,)
+        elif shading_only:
+            d = tool.Loader.surface_style_to_dict(shading_only)
+            r, g, b = d["SurfaceColour"]
+            alpha = 1 - (d.get("Transparency") or 0.0)
+            bsdf.inputs["Base Color"].default_value = (r, g, b, 1.0)
+            bsdf.inputs["Alpha"].default_value = alpha
+            if alpha < 1.0:
+                material.blend_method = "BLEND"
+            material.diffuse_color = (r, g, b, alpha)
+        # else: leave default white Principled BSDF
+        return output
+
+    @classmethod
+    def setup_dual_branch(cls, material: bpy.types.Material, ext_material: bpy.types.Material) -> bool:
+        """Build a dual-branch node tree: flat branch from IFC data + external branch from ext_material.
+
+        Clears any existing nodes and builds both branches from scratch.
+        External branch output (BIM_Output_External) is set active — Pretty mode.
+        Flat branch output (BIM_Output_Flat) is inactive — Flat mode.
+        Returns True on success; False if no shader editor is available (falls back to single-branch).
+        """
+        cls.set_use_nodes(material, True)
+        for n in material.node_tree.nodes[:]:
+            material.node_tree.nodes.remove(n)
+
+        cls._build_flat_branch_nodes(material)
+
+        ext_output = tool.Blender.copy_node_graph_additive(material, ext_material)
+        if not ext_output:
+            # No shader editor available: fall back to single-branch
+            tool.Blender.copy_node_graph(material, ext_material)
+            return False
+
+        ext_output.name = "BIM_Output_External"
+        ext_output.is_active_output = True
+        material["bim_dual_branch"] = True
+        return True
+
+    @classmethod
+    def update_external_branch(cls, material: bpy.types.Material, ext_material: bpy.types.Material) -> None:
+        """Replace the external-branch nodes of an already dual-branch material."""
+        cls._remove_external_branch(material)
+        ext_output = tool.Blender.copy_node_graph_additive(material, ext_material)
+        if ext_output:
+            ext_output.name = "BIM_Output_External"
+            ext_output.is_active_output = True
+            fast = material.node_tree.nodes.get("BIM_Output_Flat")
+            if fast:
+                fast.is_active_output = False
+
+    @classmethod
+    def sync_flat_branch_shading(
+        cls, material: bpy.types.Material, surface_colour: tuple[float, float, float], transparency: float
+    ) -> None:
+        """Update the flat-branch Principled BSDF with new shading values.
+
+        Call this after creating or editing IfcSurfaceStyleShading so the flat branch
+        stays in sync without requiring a full setup_dual_branch rebuild.
+        """
+        if not material.node_tree:
+            return
+        fast_output = material.node_tree.nodes.get("BIM_Output_Flat")
+        if not fast_output:
+            return
+        for link in fast_output.inputs["Surface"].links:
+            if link.from_node.type == "BSDF_PRINCIPLED":
+                bsdf = link.from_node
+                r, g, b = surface_colour
+                bsdf.inputs["Base Color"].default_value = (r, g, b, 1.0)
+                bsdf.inputs["Alpha"].default_value = 1.0 - transparency
+                break
+
    @classmethod
    def switch_shading(cls, blender_material: bpy.types.Material, style_type: StyleType) -> None:
        if style_type == "External":
+            ext, fast = cls.get_branch_outputs(blender_material)
+            if ext and fast:
+                ext.is_active_output = True
+                fast.is_active_output = False
+                blender_material.update_tag()
+                return
            try:
                bpy.ops.bim.activate_external_style(material_name=blender_material.name)
            except RuntimeError as error:
@@ -684,21 +994,41 @@ class Style(bonsai.core.tool.Style):
                    return
                raise error
        elif style_type == "Shading":
+            ext, fast = cls.get_branch_outputs(blender_material)
+            if ext and fast:
+                fast.is_active_output = True
+                ext.is_active_output = False
+                blender_material.update_tag()
+                return
            style_elements = tool.Style.get_style_elements(blender_material)
            rendering_style = None
            texture_style = None
+            shading_only_style = None

            for surface_style in style_elements.values():
                if surface_style.is_a() == "IfcSurfaceStyleShading":
+                    shading_only_style = surface_style
                    tool.Loader.create_surface_style_shading(blender_material, surface_style)
                elif surface_style.is_a("IfcSurfaceStyleRendering"):
                    rendering_style = surface_style
+                    shading_only_style = None  # rendering overrides shading-only path
                    tool.Loader.create_surface_style_rendering(blender_material, surface_style)
                elif surface_style.is_a("IfcSurfaceStyleWithTextures"):
                    texture_style = surface_style

            if rendering_style and texture_style:
                tool.Loader.create_surface_style_with_textures(blender_material, rendering_style, texture_style)
+            elif shading_only_style and not rendering_style:
+                # create a minimal Principled BSDF so Material Preview/Rendered shows the colour instead of white.
+                tool.Style.set_use_nodes(blender_material, True)
+                tool.Loader.restart_material_node_tree(blender_material)
+                bsdf = tool.Blender.get_material_node(blender_material, "BSDF_PRINCIPLED")
+                if bsdf:
+                    r, g, b, a = blender_material.diffuse_color
+                    bsdf.inputs["Base Color"].default_value = (r, g, b, 1)
+                    bsdf.inputs["Alpha"].default_value = a
+                    if a < 1.0:
+                        blender_material.blend_method = "BLEND"
        else:
            assert False, f"Invalid style type found: {style_type}"

@@ -744,3 +1074,36 @@ class Style(bonsai.core.tool.Style):
        elements = ifcopenshell.util.element.get_elements_by_style(tool.Ifc.get(), style)
        objects = [tool.Ifc.get_object(e) for e in elements]
        tool.Geometry.reload_representation(objects)
+
+    _last_shading_type: str | None = None
+
+    @classmethod
+    def restore_material_style_types(cls, shading_type: str) -> None:
+        """Set each IFC material's active_style_type to the richest available for the given viewport mode.
+
+        In SOLID mode all materials use "Shading".
+        In MATERIAL_PREVIEW / RENDERED, materials with an external .blend style use "External"
+        unless prefer_ifc_shading is set on that material.
+        """
+        if cls._last_shading_type == shading_type:
+            return
+        cls._last_shading_type = shading_type
+
+        for material in bpy.data.materials:
+            if not tool.Blender.get_ifc_definition_id(material):
+                continue
+            props = cls.get_material_style_props(material)
+            style_elements = cls.get_style_elements(material)
+            if shading_type == "SOLID":
+                props.active_style_type = "Shading"
+                shading = style_elements.get("IfcSurfaceStyleRendering") or style_elements.get("IfcSurfaceStyleShading")
+                if shading:
+                    d = tool.Loader.surface_style_to_dict(shading)
+                    alpha = 1.0 - (d.get("Transparency") or 0.0)
+                    material.diffuse_color = d["SurfaceColour"] + (alpha,)
+            else:  # MATERIAL_PREVIEW or RENDERED
+                if cls.has_blender_external_style(style_elements) and not props.prefer_ifc_shading:
+                    props.active_style_type = "External"
+                else:
+                    props.active_style_type = "Shading"
+            material.update_tag()
@@ -24,7 +24,7 @@ Blender versions:
 - 64-bit MacOS Intel (``macos-x64``)
 - 64-bit MacOS Silicon (``macos-arm64``)
 - 64-bit Windows (``windows-x64``)
- Blender 4.3, 4.4, or 4.5 with Python 3.11
+- Blender 5.1 or 5.2 with Python 3.13

 Developer builds may exist for different versions of Python but there will be
 no guarantee of the uptime or stability of these builds.
@@ -15,6 +15,7 @@ Example usage:

 """

+import argparse
 import shutil
 import subprocess
 import sys
@@ -27,6 +28,17 @@ if sys.platform not in available_platforms:
    print(f"Currently only available on {', '.join(available_platforms)}. Not available on {sys.platform}.")
    exit(1)

+parser = argparse.ArgumentParser(description=__doc__)
+parser.add_argument(
+    "--skip-binaries",
+    action="store_true",
+    help=(
+        "Skip copying compiled dependencies (e.g. ifcopenshell_wrapper) to the repo. "
+        "Useful if you already have the latest binaries in the repo and don't want them to be overridden."
+    ),
+)
+args = parser.parse_args()
+
 # ---------------------------
 # SETTINGS.
 # ---------------------------
@@ -125,17 +137,20 @@ def main() -> None:
        path.unlink()
    subprocess.check_call(("git", "checkout", "--", symlinks_glob), cwd=REPO_PATH)

-    print("Copying compiled dependencies to the repo...")
-    dest = REPO_PATH / "src" / "ifcopenshell-python" / "ifcopenshell"
-    for path in PACKAGE_PATH.glob("ifcopenshell/*_wrapper*"):
-        if path.suffix.lower() == ".pyi":
-            continue
-        dest_ = dest / path.name
-        print(f"Copying {path} -> {dest_}")
-        try:
-            shutil.copy(path, dest_)
-        except shutil.SameFileError:
-            pass
+    if args.skip_binaries:
+        print("Skipping copying compiled dependencies to the repo...")
+    else:
+        print("Copying compiled dependencies to the repo...")
+        dest = REPO_PATH / "src" / "ifcopenshell-python" / "ifcopenshell"
+        for path in PACKAGE_PATH.glob("ifcopenshell/*_wrapper*"):
+            if path.suffix.lower() == ".pyi":
+                continue
+            dest_ = dest / path.name
+            print(f"Copying {path} -> {dest_}")
+            try:
+                shutil.copy(path, dest_)
+            except shutil.SameFileError:
+                pass

    print("Symlinking extension to the git repo...")
    # fmt: off
@@ -16,20 +16,26 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.

+import argparse
+
 import ezdxf
 import ifcopenshell
 import ifcopenshell.guid


 class Dxf2Ifc:
+    def __init__(self, dxf_path, outfile):
+        self.dxf_path = dxf_path
+        self.outfile = outfile
+
    def execute(self):
        self.create_ifc_file()
-        doc = ezdxf.readfile("input.dxf")
+        doc = ezdxf.readfile(self.dxf_path)
        model = doc.modelspace()
        products = []
        for entity in model:
            print(entity)
-            if entity.get_mode() == "AcDbPolyFaceMesh":
+            if entity.dxftype() == "POLYLINE" and entity.is_poly_face_mesh:
                ifc_faces = []
                for face in entity.faces():
                    ifc_faces.append(
@@ -67,15 +73,18 @@ class Dxf2Ifc:
                            "Name": entity.dxf.layer,
                            "ObjectPlacement": self.placement,
                            "Representation": representation,
-                        }
+                        },
                    )
                )
            else:
-                print("Not yet implemented")
-        self.file.createIfcRelContainedInSpatialStructure(
-            ifcopenshell.guid.new(), None, None, None, products, self.site
-        )
-        self.file.write("test.ifc")
+                print(f"Skipping unsupported entity: {entity.dxftype()}")
+        if products:
+            self.file.createIfcRelContainedInSpatialStructure(
+                ifcopenshell.guid.new(), None, None, None, products, self.site
+            )
+        else:
+            print("No AcDbPolyFaceMesh entities found, writing an empty IFC")
+        self.file.write(self.outfile)

    def create_ifc_file(self):
        self.file = ifcopenshell.file()
@@ -97,14 +106,20 @@ class Dxf2Ifc:
                "Name": "DXF Conversion",
                "RepresentationContexts": [self.context],
                "UnitsInContext": units,
-            }
+            },
        )
        self.site = self.file.create_entity(
            "IfcSite",
-            **{"GlobalId": ifcopenshell.guid.new(), "Name": "DXF Conversion Site", "ObjectPlacement": self.placement}
+            **{"GlobalId": ifcopenshell.guid.new(), "Name": "DXF Conversion Site", "ObjectPlacement": self.placement},
        )
        self.file.createIfcRelAggregates(ifcopenshell.guid.new(), None, None, None, self.project, [self.site])


-dxf2ifc = Dxf2Ifc()
-dxf2ifc.execute()
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Converts DXF polyface meshes (AcDbPolyFaceMesh) to an IFC")
+    parser.add_argument("dxf", type=str, help="The input DXF file")
+    parser.add_argument("-o", "--output", type=str, help="The output IFC file", default="out.ifc")
+    args = parser.parse_args()
+
+    dxf2ifc = Dxf2Ifc(args.dxf, args.output)
+    dxf2ifc.execute()
@@ -12,16 +12,19 @@ Scenario: Ensure added booleans are marked as manual
    And I click "OK"
    And the object "IfcFurniture/Unnamed" exists
    And I toggle edit mode
-    And the object "Item/IfcExtrudedAreaSolid/73" exists
+    And the variable "extrusion" is "{ifc}.by_type('IfcExtrudedAreaSolid')[0].id()"
+    And the object "Item/IfcExtrudedAreaSolid/{extrusion}" exists
    And I open the "Add Item" menu
    When I click "Half Space Solid"
-    And the object "Item/IfcHalfSpaceSolid/90" exists
+    And the variable "half_space" is "{ifc}.by_type('IfcHalfSpaceSolid')[0].id()"
+    And the variable "boolean" is "{ifc}.by_type('IfcBooleanResult')[0].id()"
+    And the object "Item/IfcHalfSpaceSolid/{half_space}" exists
    And I deselect all objects
    And I toggle edit mode
    And I select the object "IfcFurniture/Unnamed"
    And I look at the "Property Sets" panel
    Then I see "BBIM_Boolean"
-    And I see "[91]"
+    And I see "[{boolean}]"

 Scenario: Ensure removed booleans are unmarked as manual
    Given an empty IFC project
@@ -33,17 +36,20 @@ Scenario: Ensure removed booleans are unmarked as manual
    And I click "OK"
    And the object "IfcFurniture/Unnamed" exists
    And I toggle edit mode
-    And the object "Item/IfcExtrudedAreaSolid/73" exists
+    And the variable "extrusion" is "{ifc}.by_type('IfcExtrudedAreaSolid')[0].id()"
+    And the object "Item/IfcExtrudedAreaSolid/{extrusion}" exists
    And I open the "Add Item" menu
    And I click "Half Space Solid"
+    And the variable "half_space" is "{ifc}.by_type('IfcHalfSpaceSolid')[0].id()"
+    And the variable "boolean" is "{ifc}.by_type('IfcBooleanResult')[0].id()"
    And I deselect all objects
    And I toggle edit mode
    And I select the object "IfcFurniture/Unnamed"
    And I toggle edit mode
-    And I select the object "Item/IfcHalfSpaceSolid/90"
+    And I select the object "Item/IfcHalfSpaceSolid/{half_space}"
    When I delete the selected objects
    And I toggle edit mode
    And I select the object "IfcFurniture/Unnamed"
    And I look at the "Property Sets" panel
    Then I don't see "BBIM_Boolean"
-    And I don't see "[91]"
+    And I don't see "[{boolean}]"
@@ -0,0 +1,141 @@
+# Bonsai - OpenBIM Blender Add-on
+# Copyright (C) 2026
+#
+# This file is part of Bonsai.
+#
+# Bonsai 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.
+#
+# Bonsai 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 Bonsai.  If not, see <http://www.gnu.org/licenses/>.
+#
+# This file was generated with the assistance of an AI coding tool.
+
+"""Regression tests for ``ProfileDecorator``'s ``_connected_components`` helper.
+
+Duplicating a circle/arc void's loop in Edit Mode (Tab, Tab, select the
+loop, Shift+D) copies the ``IFCARCINDEX``/``IFCCIRCLE`` vertex-group
+weights onto the new geometry, since Blender's mesh duplicate never
+allocates a new vertex group. Before this fix, ``ProfileDecorator``
+grouped arc/circle vertices by group index alone, so the duplicate's
+vertices piled into the same entry as the source loop's, failing the
+"exactly 2/3 verts" check and silently dropping *both* loops from the
+decorator until the mesh was re-imported (e.g. by leaving and re-entering
+Edit Mode). ``_connected_components`` splits each group's vertices back
+into their connected loops so a duplicate is drawn immediately, see #6944."""
+
+import bmesh
+import bpy
+import pytest
+
+from bonsai.bim.module.model.decorator import _connected_components
+
+pytestmark = pytest.mark.model
+
+
+def _bm_with_groups(verts, edges, groups):
+    """Build a standalone bmesh with a deform layer, and populate ``groups``:
+    a list of (group_index, [vert_indices]) pairs, mirroring how
+    ``tool.Model.import_profile``/``convert_curve_to_mesh`` assign one
+    vertex group per circle/arc loop."""
+    bm = bmesh.new()
+    deform_layer = bm.verts.layers.deform.new()
+    bm_verts = [bm.verts.new(v) for v in verts]
+    bm.verts.ensure_lookup_table()
+    for a, b in edges:
+        bm.edges.new((bm_verts[a], bm_verts[b]))
+    bm.verts.ensure_lookup_table()
+    bm_verts = list(bm.verts)
+    for group_index, vert_indices in groups:
+        for vi in vert_indices:
+            bm_verts[vi][deform_layer][group_index] = 1.0
+    return bm, bm_verts, deform_layer
+
+
+def _group_dict(bm_verts, deform_layer, group_index, vert_indices):
+    return {group_index: [bm_verts[i] for i in vert_indices]}
+
+
+def test_single_circle_loop_is_one_component():
+    # A circle is exactly 2 verts joined by 1 edge (tool.Model.convert_curve_to_mesh).
+    bm, bm_verts, deform_layer = _bm_with_groups(
+        verts=[(0, -1, 0), (0, 1, 0)],
+        edges=[(0, 1)],
+        groups=[(0, [0, 1])],
+    )
+    circles = _group_dict(bm_verts, deform_layer, 0, [0, 1])
+    components = _connected_components(circles)
+    assert len(components) == 1
+    assert len(components[0]) == 2
+    bm.free()
+
+
+def test_single_arc_loop_is_one_component():
+    # An arc is exactly 3 verts: endpoint-midpoint-endpoint (2 edges).
+    bm, bm_verts, deform_layer = _bm_with_groups(
+        verts=[(0, -1, 0), (0, 0, 0.3), (0, 1, 0)],
+        edges=[(0, 1), (1, 2)],
+        groups=[(0, [0, 1, 2])],
+    )
+    arcs = _group_dict(bm_verts, deform_layer, 0, [0, 1, 2])
+    components = _connected_components(arcs)
+    assert len(components) == 1
+    assert len(components[0]) == 3
+    bm.free()
+
+
+def test_duplicated_circle_loop_splits_into_two_components():
+    # Duplicating verts 0-1 (Shift+D) yields verts 2-3, connected to each
+    # other but NOT to the source loop, while keeping the same group index
+    # (0) -- exactly what bmesh.ops.duplicate produces mid Edit-Mode.
+    bm, bm_verts, deform_layer = _bm_with_groups(
+        verts=[(0, -1, 0), (0, 1, 0), (5, -1, 0), (5, 1, 0)],
+        edges=[(0, 1), (2, 3)],
+        groups=[(0, [0, 1, 2, 3])],
+    )
+    circles = _group_dict(bm_verts, deform_layer, 0, [0, 1, 2, 3])
+    components = _connected_components(circles)
+    assert len(components) == 2
+    assert sorted(len(c) for c in components) == [2, 2]
+    bm.free()
+
+
+def test_duplicated_arc_loop_splits_into_two_components():
+    bm, bm_verts, deform_layer = _bm_with_groups(
+        verts=[(0, -1, 0), (0, 0, 0.3), (0, 1, 0), (5, -1, 0), (5, 0, 0.3), (5, 1, 0)],
+        edges=[(0, 1), (1, 2), (3, 4), (4, 5)],
+        groups=[(0, [0, 1, 2, 3, 4, 5])],
+    )
+    arcs = _group_dict(bm_verts, deform_layer, 0, [0, 1, 2, 3, 4, 5])
+    components = _connected_components(arcs)
+    assert len(components) == 2
+    assert sorted(len(c) for c in components) == [3, 3]
+    bm.free()
+
+
+def test_distinct_circle_groups_stay_separate_and_correctly_sized():
+    # Multiple genuinely different circles (distinct group indices) must
+    # each still resolve to their own single 2-vert component.
+    verts = []
+    edges = []
+    groups = []
+    for i in range(5):
+        base = len(verts)
+        verts += [(i * 3, -1, 0), (i * 3, 1, 0)]
+        edges.append((base, base + 1))
+        groups.append((i, [base, base + 1]))
+    bm, bm_verts, deform_layer = _bm_with_groups(verts, edges, groups)
+    circles = {}
+    for group_index, vert_indices in groups:
+        circles[group_index] = [bm_verts[i] for i in vert_indices]
+    components = _connected_components(circles)
+    assert len(components) == 5
+    assert all(len(c) == 2 for c in components)
+    bm.free()
@@ -32,64 +32,91 @@ from test.bim.bootstrap import NewIfc
 pytestmark = pytest.mark.project


-def _make_library_only_file(*, with_child: bool = False) -> ifcopenshell.file:
-    """Build a minimal IFC4 file containing only an IfcProjectLibrary (no IfcProject).
+def _make_library_file(*, with_child: bool = False) -> ifcopenshell.file:
+    """Build a spec-valid IFC4 library file: IfcProject + IfcProjectLibrary declared to it.

-    Per IFC4+, a file must contain at least one IfcContext; IfcProjectLibrary is a
-    valid root on its own. ``with_child=True`` nests a sub-library under the root via
-    IfcRelNests, mirroring real authored library files.
+    Per the IFC Project Context concept template, every project data set (library
+    files included) shall contain exactly one IfcProject, and IfcProjectLibrary
+    instances are assigned to it via IfcRelDeclares. This matches how every library
+    file shipped in bonsai/bim/data/libraries is actually authored. ``with_child=True``
+    also nests a sub-library under the root via IfcRelNests.
    """
    library_file = ifcopenshell.api.project.create_file(version="IFC4")
+    project = ifcopenshell.api.root.create_entity(library_file, ifc_class="IfcProject", name="Demo Project")
    root = ifcopenshell.api.root.create_entity(library_file, ifc_class="IfcProjectLibrary", name="RootLib")
+    ifcopenshell.api.project.assign_declaration(library_file, definitions=[root], relating_context=project)
    if with_child:
        child = ifcopenshell.api.root.create_entity(library_file, ifc_class="IfcProjectLibrary", name="ChildLib")
        ifcopenshell.api.nest.assign_object(library_file, [child], root)
    return library_file


-class TestLibraryOnlyFile(NewIfc):
-    def test_get_root_context_returns_project_library_when_no_project(self):
-        library_file = _make_library_only_file()
-        assert not library_file.by_type("IfcProject")
+class TestLibraryFile(NewIfc):
+    """Project-library UI code operating on a spec-valid model (IfcProject root).

-        root = tool.Project.get_root_context(library_file)
+    A file containing only IfcProjectLibrary and no IfcProject is not valid IFC and
+    is not supported; see test_parent_libraries_enum_raises_for_a_file_without_a_project.
+    """

-        assert root.is_a("IfcProjectLibrary")
-        assert root.Name == "RootLib"
+    def test_parent_libraries_enum_raises_for_a_file_without_a_project(self):
+        library_file = ifcopenshell.api.project.create_file(version="IFC4")
+        ifcopenshell.api.root.create_entity(library_file, ifc_class="IfcProjectLibrary", name="RootLib")
+        IfcStore.library_file = library_file
+        try:
+            with pytest.raises(IndexError):
+                ProjectLibraryData.parent_libraries_enum()
+        finally:
+            IfcStore.library_file = None

-    def test_get_parent_library_returns_none_for_root_library(self):
-        library_file = _make_library_only_file()
+    def test_get_parent_library_returns_project_for_declared_root_library(self):
+        library_file = _make_library_file()
+        project = library_file.by_type("IfcProject")[0]
        root = library_file.by_type("IfcProjectLibrary")[0]

-        assert tool.Project.get_parent_library(root) is None
+        assert tool.Project.get_parent_library(root) == project

-    def test_get_project_hierarchy_skips_root_library(self):
-        library_file = _make_library_only_file(with_child=True)
+    def test_get_parent_library_returns_the_library_for_a_nested_sub_library(self):
+        library_file = _make_library_file(with_child=True)
+        root = next(lib for lib in library_file.by_type("IfcProjectLibrary") if lib.Name == "RootLib")
+        child = next(lib for lib in library_file.by_type("IfcProjectLibrary") if lib.Name == "ChildLib")
+
+        assert tool.Project.get_parent_library(child) == root
+
+    def test_get_parent_library_returns_none_for_an_orphaned_library(self):
+        library_file = ifcopenshell.api.project.create_file(version="IFC4")
+        orphan = ifcopenshell.api.root.create_entity(library_file, ifc_class="IfcProjectLibrary", name="Orphan")
+
+        assert tool.Project.get_parent_library(orphan) is None
+
+    def test_get_project_hierarchy_roots_libraries_under_the_project(self):
+        library_file = _make_library_file(with_child=True)
+        project = library_file.by_type("IfcProject")[0]
        root = next(lib for lib in library_file.by_type("IfcProjectLibrary") if lib.Name == "RootLib")
        child = next(lib for lib in library_file.by_type("IfcProjectLibrary") if lib.Name == "ChildLib")

        hierarchy = tool.Project.get_project_hierarchy(library_file)

-        assert root in hierarchy
+        assert root in hierarchy[project]
        assert child in hierarchy[root]

-    def test_project_library_data_loads_without_crash(self):
-        IfcStore.library_file = _make_library_only_file()
+    def test_project_library_data_loads_with_unique_enum_keys(self):
+        IfcStore.library_file = _make_library_file(with_child=True)
        try:
            ProjectLibraryData.is_loaded = False
            ProjectLibraryData.load()
            assert ProjectLibraryData.is_loaded
            enum = ProjectLibraryData.data["parent_libraries_enum"]
-            assert len(enum) == 1
-            assert enum[0][1].startswith("IfcProjectLibrary ")
+            keys = [entry[0] for entry in enum]
+            assert len(keys) == len(set(keys))
+            assert enum[0][1].startswith("IfcProject ")
        finally:
            IfcStore.library_file = None
            ProjectLibraryData.is_loaded = False

-    def test_refresh_library_succeeds_on_library_only_file(self):
+    def test_refresh_library_succeeds(self):
        import bpy

-        IfcStore.library_file = _make_library_only_file(with_child=True)
+        IfcStore.library_file = _make_library_file(with_child=True)
        try:
            result = bpy.ops.bim.refresh_library()
            assert result == {"FINISHED"}
@@ -97,13 +124,65 @@ class TestLibraryOnlyFile(NewIfc):
            IfcStore.library_file = None
            ProjectLibraryData.is_loaded = False

-    def test_add_project_library_nests_under_root_when_no_project(self):
+    def test_edit_project_library_moves_a_project_declared_library_under_another_library(self):
        import bpy

-        IfcStore.library_file = _make_library_only_file()
+        library_file = _make_library_file()
+        project = library_file.by_type("IfcProject")[0]
+        root = library_file.by_type("IfcProjectLibrary")[0]
+        target = ifcopenshell.api.root.create_entity(library_file, ifc_class="IfcProjectLibrary", name="TargetLib")
+        ifcopenshell.api.project.assign_declaration(library_file, definitions=[target], relating_context=project)
+        IfcStore.library_file = library_file
+        try:
+            props = tool.Project.get_project_props()
+            props.selected_project_library = str(root.id())
+            props.is_editing_project_library = True
+            props.parent_library = str(target.id())
+
+            result = bpy.ops.bim.edit_project_library()
+
+            assert result == {"FINISHED"}
+            assert tool.Project.get_parent_library(root) == target
+            assert root.Nests and root.Nests[0].RelatingObject == target
+            assert not root.HasContext
+        finally:
+            if props.is_editing_project_library:
+                props.is_editing_project_library = False
+            IfcStore.library_file = None
+            ProjectLibraryData.is_loaded = False
+
+    def test_edit_project_library_moves_a_nested_library_back_under_the_project(self):
+        import bpy
+
+        library_file = _make_library_file(with_child=True)
+        project = library_file.by_type("IfcProject")[0]
+        child = next(lib for lib in library_file.by_type("IfcProjectLibrary") if lib.Name == "ChildLib")
+        IfcStore.library_file = library_file
+        try:
+            props = tool.Project.get_project_props()
+            props.selected_project_library = str(child.id())
+            props.is_editing_project_library = True
+            props.parent_library = str(project.id())
+
+            result = bpy.ops.bim.edit_project_library()
+
+            assert result == {"FINISHED"}
+            assert tool.Project.get_parent_library(child) == project
+            assert child.HasContext and child.HasContext[0].RelatingContext == project
+            assert not child.Nests
+        finally:
+            if props.is_editing_project_library:
+                props.is_editing_project_library = False
+            IfcStore.library_file = None
+            ProjectLibraryData.is_loaded = False
+
+    def test_add_project_library_declares_new_library_under_the_project_root(self):
+        import bpy
+
+        IfcStore.library_file = _make_library_file()
        library_file = IfcStore.library_file
        try:
-            root = library_file.by_type("IfcProjectLibrary")[0]
+            project = library_file.by_type("IfcProject")[0]
            before = set(library_file.by_type("IfcProjectLibrary"))

            result = bpy.ops.bim.add_project_library()
@@ -113,9 +192,9 @@ class TestLibraryOnlyFile(NewIfc):
            new_libraries = after - before
            assert len(new_libraries) == 1
            new_library = next(iter(new_libraries))
-            assert new_library.Nests
-            assert new_library.Nests[0].RelatingObject == root
-            assert not new_library.HasContext
+            assert new_library.HasContext
+            assert new_library.HasContext[0].RelatingContext == project
+            assert not new_library.Nests
        finally:
            IfcStore.library_file = None
            ProjectLibraryData.is_loaded = False
@@ -21,6 +21,10 @@ from typing import Any, Optional, Union


 class bSDDClientStub:
+    def __init__(self):
+        # Mirrors bsdd.Client so tool.Bsdd.identifier_url() works against the stub.
+        self.baseurl = "https://api.bsdd.buildingsmart.org/api/"
+
    def get_dictionary(self, dictionary_uri=None, include_test_dictionaries=False):
        dicts = {
            "dictionaries": [
@@ -187,7 +187,14 @@ class PanelSpy:
            after = ""
            if self.spied_labels:
                after = self.spied_labels[-1]
-            spied_operator = {"operator": operator, "icon": icon, "text": text, "kwargs": {}, "after": after}
+            spied_operator = {
+                "operator": operator,
+                "icon": icon,
+                "text": text,
+                "kwargs": {},
+                "after": after,
+                "bl_idname": bl_idname,
+            }
            self.spied_operators.append(spied_operator)
            return OperatorSpy(spied_operator)
        elif self.spied_attr == "panel":
@@ -210,6 +217,14 @@ class OperatorSpy:
        else:
            self.spied_data["kwargs"][name] = value

+    @property
+    def bl_rna(self) -> Any:
+        # Mirror the real `UILayout.operator()` return value (an OperatorProperties
+        # instance), which exposes `.bl_rna` so panel code such as
+        # `"module" in op.bl_rna.properties` (bonsai/bim/helper.py) also works when
+        # drawing is spied on during BDD tests.
+        return getattr(bpy.types, self.spied_data["bl_idname"]).bl_rna
+

 class TemplateListSpy(PanelSpy):
    items: bpy.types.bpy_prop_collection_idprop[bpy.types.PropertyGroup]
@@ -453,6 +468,7 @@ def i_trigger_operator(operator):
@then(parsers.parse('I see "{text}"'))
 def i_see_text(text):
    assert panel_spy
+    text = replace_variables(text)
    panel_spy.refresh_spy()
    assert [l for l in panel_spy.spied_labels if text in l], f"Text {text} not found in {panel_spy.spied_labels}"

@@ -587,6 +603,7 @@ def i_select_the_row_where_i_see_text_in_the_nth_list(text, nth):
@then(parsers.parse('I don\'t see "{text}"'))
 def i_dont_see_text(text):
    assert panel_spy
+    text = replace_variables(text)
    panel_spy.refresh_spy()
    assert not [l for l in panel_spy.spied_labels if text in l], f"Text {text} found in {panel_spy.spied_labels}"

@@ -773,7 +790,11 @@ def i_create_default_mep_types():
    with bpy.context.temp_override(active_object=bpy.data.objects["IfcActuatorType/ACTUATOR"]):
        bpy.ops.bim.add_port()
        # port at cube's left side
-        bpy.data.objects["IfcDistributionPort/Port"].location = (-0.5, 0, 0)
+        # Newly created ports are never given an explicit IFC `.Name` (see
+        # `core/system.py:create_port_at_cursor` / `tool/system.py`), so
+        # `tool.Loader.get_name()` falls back to the standard "Unnamed" convention
+        # used throughout Bonsai for freshly-created, not-yet-named elements.
+        bpy.data.objects["IfcDistributionPort/Unnamed"].location = (-0.5, 0, 0)
        bpy.ops.bim.hide_ports()


@@ -1073,6 +1094,7 @@ def then_the_object_name_is_placed_in_the_collection_collection(name: str, colle
@given(parsers.parse('additionally the object "{name}" is selected'))
@when(parsers.parse('additionally the object "{name}" is selected'))
 def additionally_the_object_name_is_selected(name):
+    name = replace_variables(name)
    obj = bpy.context.scene.objects.get(name)
    if not obj:
        total = len(bpy.context.scene.objects)
@@ -1153,6 +1175,7 @@ def nothing_happens():
@when(parsers.parse('the object "{name}" exists'))
@then(parsers.parse('the object "{name}" exists'))
 def the_object_name_exists(name: str) -> bpy.types.Object:
+    name = replace_variables(name)
    # Some objects from linked collections may share the same name. This disambiguates them.
    if name.startswith("Col:"):
        _, collection_name, name = name.split(":")
@@ -1167,6 +1190,7 @@ def the_object_name_exists(name: str) -> bpy.types.Object:

@then(parsers.parse('the object "{name}" does not exist'))
 def the_object_name_does_not_exist(name) -> None:
+    name = replace_variables(name)
    obj = bpy.data.objects.get(name)
    assert obj is None, f'The object "{name}" exists'

--- a/Show More
+++ b/Show More