Merge branch 'v0.8.0' into ifcmax/initial-refresh

.gitignore

@@ -82,6 +82,8 @@ src/bonsai/bonsai/translations.py
 
 # bonsai test temp files
 src/bonsai/test/files/temp
+src/bonsai/test/files/basic.ifc.cache.blend
+src/bonsai/test/files/basic.ifc.cache.sqlite
 
 # bonsai data
 src/bonsai/bonsai/bim/data/build/

AGENTS.md

@@ -0,0 +1,153 @@
+<!-- This file was generated with the assistance of an AI coding tool. -->
+
+# AGENTS.md
+
+Guidelines for AI coding agents contributing to IfcOpenShell. This file is
+intended to be read by all AI agents regardless of platform (Claude Code,
+Copilot, Cursor, etc.) in addition to any tool-specific configuration files.
+
+Human contributors using AI tools should also read this document carefully,
+as they are responsible for ensuring their contributions comply with these
+guidelines.
+
+## Project Overview
+
+IfcOpenShell is an open source library for working with Industry Foundation
+Classes (IFC). It provides C++ and Python APIs, geometry processing, and an
+ecosystem of tools including IfcConvert and the Bonsai Blender add-on.
+
+## Licensing
+
+All contributions must be compatible with the project's licensing:
+
+- **Library code** (everything except Bonsai): **LGPL-3.0-or-later**
+- **Bonsai** (`src/bonsai/`): **GPL-3.0-or-later**
+
+There is no Contributor License Agreement (CLA). By submitting a pull request,
+you agree that your contribution is licensed under the applicable license above.
+
+## Indicating AI-Generated Code
+
+Contributors must clearly indicate when code has been generated or
+substantially written by an AI tool.
+
+### Commits
+
+Commits that modify existing code must include a note in the **body** of the
+commit message (not the subject line) indicating that the change was
+AI-generated. For example:
+
+```
+Fix off-by-one error in element iteration
+
+The loop termination condition was incorrect when processing
+IfcRelAggregates relationships.
+
+Generated with the assistance of an AI coding tool.
+```
+
+### New Files
+
+New files that are AI-generated must include a comment near the top of the
+file indicating this. Use the appropriate comment syntax for the language:
+
+```python
+# This file was generated with the assistance of an AI coding tool.
+```
+
+```cpp
+// This file was generated with the assistance of an AI coding tool.
+```
+
+### Pull Requests
+
+Pull requests containing AI-generated code must indicate in the PR description
+which parts of the contribution are AI-generated. If the entire PR is
+AI-generated, state that clearly. If only specific commits or files are
+AI-generated, identify them.
+
+## Pull Request Guidelines
+
+### Scope and Size
+
+- Each pull request should address a **single issue or feature**.
+- Do not mix unrelated changes (e.g., bug fixes with refactoring or style
+  changes) in the same PR.
+- Large pull requests should be broken down into **multiple small, standalone
+  commits** that are each easy to review independently. Rewrite commit history
+  for this purpose if necessary.
+- PRs that are minimal, focused solutions to a specific problem are much more
+  likely to be accepted.
+
+### What to Avoid
+
+- **Over-engineering**: Do not add features, abstractions, or configurability
+  beyond what is needed to solve the immediate problem.
+- **Scope creep**: Do not make changes to files or code that are not directly
+  related to the task at hand.
+- **Unnecessary additions**: Do not add docstrings, comments, type annotations,
+  or error handling to code you did not otherwise need to change.
+- **Cosmetic changes**: Do not reformat, rename, or reorganize code that is
+  unrelated to your change.
+
+## Commit Messages
+
+- The **subject line** must be **50 characters or less**.
+- Use the **imperative mood** (e.g., "Fix crash in geometry kernel", not
+  "Fixed crash" or "Fixes crash").
+- A commit message can be a single line if the purpose is obvious from the
+  subject alone.
+- Otherwise, add a blank line after the subject followed by a short explanation
+  of a few lines in the body.
+
+## Code Style
+
+### Python
+
+- **Line length**: 120 characters
+- **Formatter**: black
+- **Linter**: ruff
+- Configuration is in `pyproject.toml`
+
+### C++
+
+- **Standard**: C++17 minimum
+- **Formatter**: clang-format (configuration in `.clang-format`)
+- **Linter**: clang-tidy (configuration in `.clang-tidy`)
+
+Run linters and formatters **before submitting** your pull request. Do not rely
+on CI to catch formatting issues.
+
+## Testing
+
+- Pull requests with test coverage are **much more likely to be merged**.
+- If tests are appropriate and feasible for your change, they should be
+  included.
+- Tests are not required for every change (e.g., documentation-only changes),
+  but the expectation is that testable code changes come with tests.
+- Python tests use **pytest** and are located in `test/` or `tests/` directories
+  within each package under `src/`.
+- Run the existing test suite for the package you modified before submitting.
+
+## Architecture Quick Reference
+
+### Directory Structure
+
+- `src/ifcparse/` — C++ IFC file parsing
+- `src/ifcgeom/` — C++ geometry processing (OpenCASCADE and CGAL kernels)
+- `src/serializers/` — Output format serializers (glTF, Collada, SVG, etc.)
+- `src/ifcwrap/` — SWIG Python bindings
+- `src/ifcconvert/` — CLI conversion tool
+- `src/ifcopenshell-python/` — Python API (`ifcopenshell` package)
+- `src/bonsai/` — Blender add-on (GPL-3.0-or-later)
+- `src/ifctester/` — IDS model auditing
+- `src/ifcpatch/` — IFC file manipulation scripts
+- `src/ifcdiff/` — IFC model comparison
+- `src/ifcclash/` — Clash detection
+- `src/ifccsv/` — Schedule import/export
+
+### IFC Schema Versions
+
+The library supports IFC2x3 TC1, IFC4 Add2 TC1, IFC4x1, IFC4x2, and
+IFC4x3 Add2. Schema-specific code is compiled conditionally. Be aware of
+which schema versions your change affects.

pyproject.toml

@@ -3,7 +3,7 @@ name = "IfcOpenShell"
 version = "0.0.0"
 dependencies = [
     "black==26.1.0",
-    "ruff==0.15.0",
+    "ruff==0.15.1",
     "poethepoet",
     "gersemi==0.25.4",
 ]

src/bonsai/Makefile

@@ -371,7 +371,7 @@ test-tool:
 ifndef MODULE
 	pytest test/tool
 else
-	pytest test/tool/test_$(MODULE).py
+	pytest test/tool/test_$(MODULE).py --maxfail=1
 endif
 
 # Reregistering test is not added to the standard test suite because during unregister

src/bonsai/bonsai/bim/export_ifc.py

@@ -52,7 +52,6 @@ class IfcExporter:
         self.set_header()
         IfcStore.update_cache()
         self.sync_all_objects()
-        tool.Project.save_linked_models_to_ifc()
         extension = self.ifc_export_settings.output_file.split(".")[-1].lower()
         if extension == "ifczip":
             with tempfile.TemporaryDirectory() as unzipped_path:

src/bonsai/bonsai/bim/module/bsdd/ui.py

@@ -24,6 +24,7 @@ import bpy
 from bpy.types import Panel, UIList
 
 import bonsai.tool as tool
+import bsdd
 from bonsai.bim.module.bsdd.data import BSDDData
 
 if TYPE_CHECKING:
@@ -83,7 +84,6 @@ class BIM_PT_bsdd(Panel):
             row = self.layout.row()
             row.operator("bim.load_bsdd_dictionaries")
 
-
 class BIM_UL_bsdd_dictionaries(UIList):
     def draw_item(
         self,

src/bonsai/bonsai/bim/module/drawing/operator.py

@@ -928,7 +928,7 @@ class CreateDrawing(bpy.types.Operator):
 
         props = tool.Project.get_project_props()
         for link in props.get_loaded_links_for_drawings():
-            files[link.name] = self.get_linked_file(link)
+            files[link.filepath] = self.get_linked_file(link)
 
         target_view = ifcopenshell.util.element.get_psets(self.camera_element)["EPset_Drawing"]["TargetView"]
         self.setup_serialiser(target_view)
@@ -1374,7 +1374,7 @@ class CreateDrawing(bpy.types.Operator):
         return True
 
     def get_linked_file(self, link: "Link") -> ifcopenshell.file:
-        link_path = link.name
+        link_path = link.filepath
         ifc_file = IfcStore.session_files.get(link_path, None)
         if ifc_file is not None:
             return ifc_file
@@ -2896,12 +2896,16 @@ class AddSchedule(bpy.types.Operator, tool.Ifc.Operator, ImportHelper):
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Add an .ods, .xls or .xlsx file as a schedule"
 
+    files: bpy.props.CollectionProperty(name="Files", type=bpy.types.OperatorFileListElement)
+    directory: bpy.props.StringProperty(subtype="DIR_PATH")
     filter_glob: bpy.props.StringProperty(default="*.ods;*.xls;*.xlsx", options={"HIDDEN"})
     use_relative_path: bpy.props.BoolProperty(name="Use Relative Path", default=True)
 
     def _execute(self, context):
-        filepath = tool.Ifc.get_uri(self.filepath, use_relative_path=self.use_relative_path)
+        for filepath in tool.Blender.get_selected_files(
-        core.add_document(tool.Ifc, tool.Drawing, "SCHEDULE", uri=filepath)
+            self.directory, self.files, use_relative_path=self.use_relative_path
+        ):
+            core.add_document(tool.Ifc, tool.Drawing, "SCHEDULE", uri=filepath)
 
 
 class RemoveSchedule(bpy.types.Operator, tool.Ifc.Operator):
@@ -3090,23 +3094,16 @@ class AddReference(bpy.types.Operator, tool.Ifc.Operator, ImportHelper):
     bl_description = "Import a .svg file to the project as a reference"
     bl_options = {"REGISTER", "UNDO"}
 
+    files: bpy.props.CollectionProperty(name="Files", type=bpy.types.OperatorFileListElement)
+    directory: bpy.props.StringProperty(subtype="DIR_PATH")
     filter_glob: bpy.props.StringProperty(default="*.svg", options={"HIDDEN"})
     use_relative_path: bpy.props.BoolProperty(name="Use Relative Path", default=True)
     filename_ext = ".svg"
 
-    files: bpy.props.CollectionProperty(type=bpy.types.OperatorFileListElement)
-    directory: bpy.props.StringProperty(subtype="DIR_PATH")
-
     def _execute(self, context):
-        # Handle both single and multiple file selection
+        for filepath in tool.Blender.get_selected_files(
-        if self.files:
+            self.directory, self.files, use_relative_path=self.use_relative_path
-            for file_elem in self.files:
+        ):
-                filepath = os.path.join(self.directory, file_elem.name)
-                uri = tool.Ifc.get_uri(filepath, use_relative_path=self.use_relative_path)
-                core.add_document(tool.Ifc, tool.Drawing, "REFERENCE", uri=uri)
-        else:
-            # Fallback for single file (backward compatibility)
-            filepath = tool.Ifc.get_uri(self.filepath, use_relative_path=self.use_relative_path)
             core.add_document(tool.Ifc, tool.Drawing, "REFERENCE", uri=filepath)
 
 
@@ -3165,6 +3162,7 @@ class EditTextPopup(bpy.types.Operator):
         bpy.ops.bim.disable_editing_text()
 
     def execute(self, context):
+        # TODO: check for possible subtle undo bug here
         # can't use invoke() because this operator
         # will be run indirectly by hotkey
         # so we use execute() and track whether it's the first run of the operator
@@ -3817,91 +3815,14 @@ class AddReferenceImage(bpy.types.Operator, tool.Ifc.Operator, ImportHelper):
         description="Existing object name to add a style with reference image to. If not provided will create a new object.",
         options={"SKIP_SAVE"},
     )
-
+    size: bpy.props.FloatProperty(name="Size", description="Size of the reference image", default=1.0, unit="LENGTH")
-    x_length: bpy.props.FloatProperty(
-        name="X Length",
-        description="Width of the reference image in project units",
-        default=1.0,
-        min=0.001,
-        soft_min=0.01,
-        precision=3,
-    )
-    y_length: bpy.props.FloatProperty(
-        name="Y Length",
-        description="Height of the reference image in project units",
-        default=1.0,
-        min=0.001,
-        soft_min=0.01,
-        precision=3,
-    )
-
-    show_dimensions_dialog: bpy.props.BoolProperty(default=False, options={"HIDDEN", "SKIP_SAVE"})
 
     def draw(self, context):
-        layout = self.layout
+        if Path(tool.Ifc.get_path()).is_file():
-
+            self.layout.prop(self, "use_relative_path")
-        if getattr(self, "show_dimensions_dialog", False):
+        self.layout.prop(self, "override_existing_image")
-            if tool.Ifc.get():
+        self.layout.prop(self, "use_existing_object_by_name")
-                length_unit = ifcopenshell.util.unit.get_project_unit(tool.Ifc.get(), "LENGTHUNIT")
+        self.layout.prop(self, "size")
-                if length_unit:
-                    unit_name = ifcopenshell.util.unit.get_full_unit_name(length_unit).lower()
-                else:
-                    unit_name = "project units"
-                layout.label(text=f"Set Reference Image Dimensions (in {unit_name}):")
-            else:
-                layout.label(text="Set Reference Image Dimensions (in project units):")
-            layout.separator()
-            layout.prop(self, "x_length")
-            layout.prop(self, "y_length")
-        else:
-            if Path(tool.Ifc.get_path()).is_file():
-                layout.prop(self, "use_relative_path")
-            else:
-                self.use_relative_path = False
-                layout.label(text="Save the .ifc file first ")
-                layout.label(text="to use relative paths.")
-            layout.prop(self, "override_existing_image")
-            layout.prop(self, "use_existing_object_by_name")
-
-    def invoke(self, context, event):
-        if not getattr(self, "show_dimensions_dialog", False):
-            context.window_manager.fileselect_add(self)
-            return {"RUNNING_MODAL"}
-        else:
-            return context.window_manager.invoke_props_dialog(self)
-
-    def execute(self, context):
-        if not getattr(self, "show_dimensions_dialog", False):
-            abs_path = Path(self.filepath).absolute().resolve()
-            if self.override_existing_image:
-                params = {"check_existing": True, "force_reload": True}
-            else:
-                params = {"check_existing": False}
-
-            try:
-                image = load_image(abs_path.name, str(abs_path.parent), **params)
-
-                image_width_px = image.size[0]
-                image_height_px = image.size[1]
-                aspect_ratio = image_width_px / image_height_px
-
-                if aspect_ratio >= 1.0:
-                    self.x_length = 1.0
-                    self.y_length = 1.0 / aspect_ratio
-                else:
-                    self.x_length = aspect_ratio
-                    self.y_length = 1.0
-
-                bpy.data.images.remove(image)
-
-            except Exception as e:
-                self.report({"ERROR"}, f"Failed to load image: {str(e)}")
-                return {"CANCELLED"}
-
-            self.show_dimensions_dialog = True
-            return context.window_manager.invoke_props_dialog(self)
-
-        return self._execute(context)
 
     def _execute(self, context):
         space = tool.Blender.get_view3d_space()
@@ -3922,11 +3843,19 @@ class AddReferenceImage(bpy.types.Operator, tool.Ifc.Operator, ImportHelper):
             params = {"check_existing": False}
         image = load_image(abs_path.name, str(abs_path.parent), **params)
 
+        aspect_ratio = image.size[0] / image.size[1]
+        if aspect_ratio >= 1.0:  # Landscape
+            x_length = self.size
+            y_length = self.size / aspect_ratio
+        else:
+            x_length = self.size / aspect_ratio
+            y_length = self.size
+
         def bm_add_image_plane(mesh):
             bm = tool.Blender.get_bmesh_for_mesh(mesh, clean=True)
 
             unit_scale = ifcopenshell.util.unit.calculate_unit_scale(ifc_file)
-            plane_scale = Vector((self.x_length * unit_scale / 2.0, self.y_length * unit_scale / 2.0, 1.0))
+            plane_scale = Vector((x_length / 2.0, y_length / 2.0, 1.0))
             matrix = Matrix.LocRotScale(None, None, plane_scale)
             bmesh.ops.create_grid(bm, x_segments=1, y_segments=1, size=1, matrix=matrix, calc_uvs=False)
 
@@ -4030,8 +3959,6 @@ class AddReferenceImage(bpy.types.Operator, tool.Ifc.Operator, ImportHelper):
         tool.Style.reload_material_from_ifc(material)
         tool.Geometry.record_object_materials(obj)
 
-        return {"FINISHED"}
-
 
 class ConvertSVGToDXF(bpy.types.Operator):
     bl_idname = "bim.convert_svg_to_dxf"

src/bonsai/bonsai/bim/module/drawing/ui.py

@@ -89,7 +89,7 @@ class BIM_PT_camera(Panel):
                     for link in links:
                         row = panel.row(align=True)
                         split = row.split(factor=0.9)
-                        split.label(text=link.name, icon="FILE")
+                        split.label(text=link.filepath, icon="FILE")
                         split.prop(link, "include_in_drawings", text="")
                 else:
                     panel.label(text="No IFC projects linked and loaded.")

src/bonsai/bonsai/bim/module/geometry/operator.py

@@ -902,6 +902,7 @@ class OverrideDelete(bpy.types.Operator):
 
             if not is_valid_data_block:
                 continue
+            
             element = tool.Ifc.get_entity(obj)
             if element:
                 if tool.Geometry.is_locked(element):
@@ -912,6 +913,9 @@ class OverrideDelete(bpy.types.Operator):
                 if ifcopenshell.util.element.get_pset(element, "BBIM_Array"):
                     self.report({"INFO"}, "Elements that are part of an array cannot be deleted.")
                     continue
+                if element.is_a("IfcDocumentReference"):
+                    self.report({"INFO"}, "Linked models cannot be deleted.")
+                    continue
                 if element.is_a("IfcGridAxis"):
                     # Deleting the last W axis is OK
                     if ((grid := element.PartOfU) and len(grid[0].UAxes) == 1) or (
@@ -1208,6 +1212,11 @@ class OverrideDuplicateMove(bpy.types.Operator):
                 operator.report({"ERROR"}, f"Drawing '{obj.name}' not duplicated.")
                 continue
 
+            if element.is_a("IfcDocumentReference"):
+                objects_to_remove.add(obj)
+                operator.report({"ERROR"}, f"Linked model '{obj.name}' not duplicated.")
+                continue
+
             if tool.Geometry.is_locked(element):
                 objects_to_remove.add(obj)
                 operator.report({"ERROR"}, lock_error_message(obj.name))

src/bonsai/bonsai/bim/module/georeference/operator.py

@@ -51,7 +51,7 @@ class RemoveGeoreferencing(bpy.types.Operator, tool.Ifc.Operator):
     bl_description = "Remove the georeferencing"
 
     def _execute(self, context):
-        core.remove_georeferencing(tool.Ifc)
+        core.remove_georeferencing(tool.Ifc, tool.Georeference)
 
 
 class EditGeoreferencing(bpy.types.Operator, tool.Ifc.Operator):

src/bonsai/bonsai/bim/module/georeference/prop.py

@@ -224,16 +224,12 @@ class BIMGeoreferenceProperties(PropertyGroup):
     x_axis_ordinate: StringProperty(name="X Axis Ordinate", update=update_grid_north_vector)
     x_axis_is_null: BoolProperty(name="X Axis Is Null")
 
-    # These are only for reference to capture data about a host model from a linked model
-    # If you relink a model from a new host origin, we can autodetect it in theory with this
-    host_model_origin: StringProperty(name="Host Model Origin")
-    host_model_origin_si: StringProperty(name="Host Model Origin SI")
-    host_model_project_north: StringProperty(name="Host Model Angle to Grid North")
-
     # This is the ENH in project units and SI units of the Blender session's 0,0,0.
     # These are only for reference, using tool.Georeference.set_model_origin on
     # project load, project create, and when linking for the first time from an
     # empty Blender session.
+    model_is_georeferenced: BoolProperty(name="Model Is Georeferenced")
+    model_crs: StringProperty(name="Model CRS")
     model_origin: StringProperty(name="Model Origin")
     model_origin_si: StringProperty(name="Model Origin SI")
     model_project_north: StringProperty(name="Model Angle to Grid North")
@@ -275,10 +271,6 @@ class BIMGeoreferenceProperties(PropertyGroup):
         x_axis_ordinate: str
         x_axis_is_null: bool
 
-        host_model_origin: str
-        host_model_origin_si: str
-        host_model_project_north: str
-
         model_origin: str
         model_origin_si: str
         model_project_north: str

src/bonsai/bonsai/bim/module/project/__init__.py

@@ -31,27 +31,31 @@ classes = (
     operator.BIM_OT_load_clipping_planes,
     operator.BIM_OT_save_clipping_planes,
     operator.ChangeLibraryElement,
+    operator.ClearMeasurement,
     operator.ClearRecentIFCProjects,
     operator.CreateClippingPlane,
     operator.CreateProject,
     operator.DisableCulling,
     operator.DisableEditingHeader,
+    operator.DisableEditingLink,
     operator.EditHeader,
+    operator.EditLink,
     operator.EditProjectLibrary,
     operator.EnableCulling,
     operator.EnableEditingHeader,
+    operator.EnableEditingLink,
     operator.ExportIFC,
     operator.FlipClippingPlane,
     operator.IFCFileHandlerOperator,
     operator.ImageScalingTool,
     operator.LinkIfc,
+    operator.LoadBlendMetadataAndIFC,
     operator.LoadLink,
     operator.LoadLinkedProject,
     operator.LoadProject,
     operator.LoadProjectElements,
-    operator.MeasureTool,
     operator.MeasureFaceAreaTool,
-    operator.ClearMeasurement,
+    operator.MeasureTool,
     operator.NewProject,
     operator.QueryLinkedElement,
     operator.RefreshClippingPlanes,
@@ -69,7 +73,6 @@ classes = (
     operator.UnassignLibraryDeclaration,
     operator.UnlinkIfc,
     operator.UnloadLink,
-    operator.LoadBlendMetadataAndIFC,
     workspace.ExploreHotkey,
     prop.LibraryBreadcrumb,
     prop.LibraryElement,

src/bonsai/bonsai/bim/module/project/operator.py

@@ -18,6 +18,7 @@
 
 import datetime
 import json
+import math
 import logging
 import os
 import subprocess
@@ -59,6 +60,15 @@ import bonsai.core.project as core
 import bonsai.tool as tool
 from bonsai.bim import export_ifc, import_ifc
 from bonsai.bim.ifc import IfcStore
+from bonsai.bim.ui import IFCFileSelector
+from bonsai.bim import import_ifc
+from bonsai.bim import export_ifc
+from math import radians, degrees
+from pathlib import Path
+from collections import defaultdict
+from mathutils import Vector, Matrix
+from bpy.app.handlers import persistent
+from ifcopenshell.geom import ShapeElementType
 from bonsai.bim.module.model.decorator import FaceAreaDecorator, PolylineDecorator
 from bonsai.bim.module.model.polyline import PolylineOperator
 from bonsai.bim.module.project.data import LinksData, ProjectLibraryData
@@ -1321,7 +1331,7 @@ class ToggleFilterCategories(bpy.types.Operator):
         return {"FINISHED"}
 
 
-class LinkIfc(bpy.types.Operator, ImportHelper):
+class LinkIfc(bpy.types.Operator, ImportHelper, tool.Ifc.Operator):
     bl_idname = "bim.link_ifc"
     bl_label = "Link IFC"
     bl_options = {"REGISTER", "UNDO"}
@@ -1360,134 +1370,125 @@ class LinkIfc(bpy.types.Operator, ImportHelper):
             row = self.layout.row()
             row.prop(pprops, "project_north")
 
-    def execute(self, context):
+    def _execute(self, context):
         start = time.time()
         files = [f.name for f in self.files] if self.files else [self.filepath]
+
+        if not files or all(not f or not f.strip() for f in files):
+            self.report({"ERROR"}, "No file selected")
+            return {"CANCELLED"}
+
+        existing_links = tool.Project.get_linked_models_documents() if tool.Ifc.get() else {}
         for filename in files:
+            if not filename or not filename.strip():
+                continue
             filepath = Path(self.directory) / filename
             if bpy.data.filepath and filepath.samefile(bpy.data.filepath):
                 self.report({"INFO"}, "Can't link the current .blend file")
                 continue
             props = tool.Project.get_project_props()
-            new = props.links.add()
             filepath = tool.Ifc.get_uri(filepath, use_relative_path=self.use_relative_path)
+
+            new = props.links.add()
+            if tool.Ifc.get():
+                if not (document := existing_links.get(filepath)):
+                    document = ifcopenshell.api.document.add_information(tool.Ifc.get())
+                    document.Name = Path(filepath).name
+                    document.Scope = "LINKED_MODEL"
+                reference = ifcopenshell.api.document.add_reference(tool.Ifc.get(), information=document)
+                reference[1] = ",".join([str(o) for o in np.eye(4).flatten().tolist()])
+                reference.Location = filepath.replace("\\", "/")
+                new.ifc_definition_id = reference.id()
             new.name = filepath
-            status = bpy.ops.bim.load_link(filepath=filepath, use_cache=self.use_cache)
+            new.filepath = filepath
-            if status == {"CANCELLED"}:
+            bpy.ops.bim.load_link(link_index=-1, use_cache=self.use_cache)
-                error_msg = (
-                    f'Error processing IFC file "{filepath}" '
-                    "was critical and blend file either wasn't saved or wasn't updated. "
-                    "See logs above in system console for details."
-                )
-                print(error_msg)
-                self.report({"ERROR"}, error_msg)
-                return {"FINISHED"}
-        print(f"Finished linking {len(files)} IFCs", time.time() - start)
-        return {"FINISHED"}
 
 
-class UnlinkIfc(bpy.types.Operator):
+class UnlinkIfc(bpy.types.Operator, tool.Ifc.Operator):
     bl_idname = "bim.unlink_ifc"
     bl_label = "Unlink IFC"
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Remove the selected file from the link list"
-    filepath: bpy.props.StringProperty()
+    link_index: bpy.props.IntProperty(name="Link Index")
 
-    def execute(self, context):
+    def _execute(self, context):
-        filepath = Path(self.filepath).as_posix()
-        bpy.ops.bim.unload_link(filepath=filepath)
         props = tool.Project.get_project_props()
-        index = props.links.find(filepath)
+        link = props.links[self.link_index]
-        if index != -1:
+        bpy.ops.bim.unload_link(link_index=self.link_index)
-            props.links.remove(index)
+        if tool.Ifc.get():
-        return {"FINISHED"}
+            reference = tool.Ifc.get().by_id(link.ifc_definition_id)
+            document = tool.Document.get_reference_document(reference)
+            ifcopenshell.api.document.remove_reference(tool.Ifc.get(), reference)
+            if document and not tool.Document.get_document_references(document):
+                ifcopenshell.api.document.remove_information(tool.Ifc.get(), document)
+        props.links.remove(self.link_index)
 
 
-class UnloadLink(bpy.types.Operator):
+class UnloadLink(bpy.types.Operator, tool.Ifc.Operator):
     bl_idname = "bim.unload_link"
     bl_label = "Unload Link"
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Unload the selected linked file"
-    filepath: bpy.props.StringProperty()
+    link_index: bpy.props.IntProperty(name="Link Index")
 
-    def execute(self, context):
+    def _execute(self, context):
-        filepath = tool.Blender.ensure_blender_path_is_abs(Path(self.filepath))
+        link = tool.Project.get_project_props().links[self.link_index]
-        if filepath.suffix.lower() == ".ifc":
+        if obj := tool.Project.get_link_empty_handle(link):
-            filepath = filepath.with_suffix(".ifc.cache.blend")
+            collection = obj.instance_collection
-
+            library = collection.library
-        for library in list(bpy.data.libraries):
+            tool.Ifc.unlink(obj=obj)
-            if tool.Blender.ensure_blender_path_is_abs(Path(library.filepath)) == filepath:
+            bpy.data.objects.remove(obj)
+            if collection.users == 0:
+                bpy.data.collections.remove(collection)
+            if not len([c for c in bpy.data.collections if c.library == library]):
                 bpy.data.libraries.remove(library)
-
-        props = tool.Project.get_project_props()
-        links = props.links
-        link = links[self.filepath]
-        # Let's assume that user might delete it.
-        if empty_handle := link.empty_handle:
-            bpy.data.objects.remove(empty_handle)
-
-        # following lines removes the library also when use_relative_path=True, otherwise it doesn't
-        libraries = bpy.data.libraries
-        for library in libraries:
-            if library.name == self.filepath + ".cache.blend":
-                bpy.data.libraries.remove(library)
-
         link.is_loaded = False
-
+        ProjectDecorator.uninstall()
-        if not any([l.is_loaded for l in links]):
-            ProjectDecorator.uninstall()
-        # we make sure we don't draw queried object from the file that was just unlinked
-        elif queried_obj := props.queried_obj:
-            queried_filepath = Path(queried_obj["ifc_filepath"])
-            if queried_filepath == filepath:
-                ProjectDecorator.uninstall()
-
-        return {"FINISHED"}
 
 
-class LoadLink(bpy.types.Operator):
+class LoadLink(bpy.types.Operator, tool.Ifc.Operator):
     bl_idname = "bim.load_link"
     bl_label = "Load Link"
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Load the selected file"
-    filepath: bpy.props.StringProperty(name="Link Filepath")
+    link_index: bpy.props.IntProperty(name="Link Index")
     use_cache: bpy.props.BoolProperty(name="Use Cache", default=True)
 
-    filepath_: Path
+    def _execute(self, context):
-
+        self.link = tool.Project.get_project_props().links[self.link_index]
-    def execute(self, context):
+        filepath = Path(tool.Ifc.resolve_uri(self.link.filepath))
-        filepath = Path(tool.Ifc.resolve_uri(self.filepath))
         if not filepath.exists():
             self.report({"ERROR"}, f"File does not exist: '{filepath}'")
             return {"CANCELLED"}
         self.filepath_ = filepath
-        if filepath.suffix.lower().endswith(".blend"):
+        if filepath.suffix.lower().endswith(".ifc"):
-            self.link_blend(filepath)
+            return self.link_ifc()
-        elif filepath.suffix.lower().endswith(".ifc"):
-            status = self.link_ifc()
-            if status:
-                return status
-        return {"FINISHED"}
 
     def link_blend(self, filepath: Path) -> None:
         with bpy.data.libraries.load(str(filepath), link=True) as (data_from, data_to):
-            data_to.scenes = data_from.scenes
+            data_to.collections = [c for c in data_from.collections if "IfcProject" in c]
-        link = tool.Project.get_project_props().links[self.filepath]
+
-        for scene in bpy.data.scenes:
+        # Find the linked collection
-            if not scene.library or Path(scene.library.filepath) != filepath:
+        for collection in bpy.data.collections:
+            if not collection.library or Path(collection.library.filepath) != filepath:
                 continue
-            for child in scene.collection.children:
+            # Create unique empty instance for this link
-                if "IfcProject" not in child.name:
+            empty_name = collection.name
-                    continue
+            empty = bpy.data.objects.new(empty_name, None)
-                empty = bpy.data.objects.new(child.name, None)
+            empty.instance_type = "COLLECTION"
-                empty.instance_type = "COLLECTION"
+            empty.instance_collection = collection
-                empty.instance_collection = child
+            empty.matrix_world = Matrix(tool.Project.calculate_link_matrix(self.link))
-                link.empty_handle = empty
+
-                bpy.context.scene.collection.objects.link(empty)
+            tool.Project.set_link_empty_handle(self.link, empty)
-                break
+            bpy.context.scene.collection.objects.link(empty)
+            self.link.is_loaded = True
+            if tool.Ifc.get():  # For non-IFC projects, locking has no meaning
+                tool.Geometry.lock_object(empty)
+            tool.Blender.select_and_activate_single_object(bpy.context, empty)
             break
-        link.is_loaded = True
+        else:
-        tool.Blender.select_and_activate_single_object(bpy.context, empty)
+            print(f"WARNING: No IfcProject collection found in {filepath}")
+            self.link.is_loaded = False
 
     def link_ifc(self) -> Union[set[str], None]:
         blend_filepath = self.filepath_.with_suffix(".ifc.cache.blend")
@@ -1502,14 +1503,12 @@ class LoadLink(bpy.types.Operator):
 
             code = f"""
 import bpy
+import sys
 
 def run():
     import bonsai.tool as tool
     gprops = tool.Georeference.get_georeference_props()
     # Our model origin becomes their host model origin
-    gprops.host_model_origin = "{gprops.model_origin}"
-    gprops.host_model_origin_si = "{gprops.model_origin_si}"
-    gprops.host_model_project_north = "{gprops.model_project_north}"
     gprops.has_blender_offset = {gprops.has_blender_offset}
     gprops.blender_offset_x = "{gprops.blender_offset_x}"
     gprops.blender_offset_y = "{gprops.blender_offset_y}"
@@ -1522,7 +1521,12 @@ def run():
     pprops.false_origin = "{pprops.false_origin}"
     pprops.project_north = "{pprops.project_north}"
     # Use absolute path to be safe from cwd changes.
-    bpy.ops.bim.load_linked_project(filepath=r"{str(self.filepath_)}")
+    try:
+        bpy.ops.bim.load_linked_project(filepath=r"{str(self.filepath_)}")
+    except RuntimeError as e:
+        # Operator failed (returned CANCELLED with error report)
+        print(f"Failed to load linked project: {{e}}")
+        sys.exit(1)
     # Use str instead of as_posix to avoid issues with Windows shared paths.
     bpy.ops.wm.save_as_mainfile(filepath=r"{str(blend_filepath)}")
 
@@ -1556,14 +1560,17 @@ except Exception as e:
                 if not blend_filepath.exists() or blend_filepath.stat().st_mtime < t:
                     return {"CANCELLED"}
 
-            self.set_model_origin_from_link()
+        self.set_model_origin_from_link()
-
+        self.set_georeferencing_indicator()
         self.link_blend(blend_filepath)
 
     def set_model_origin_from_link(self) -> None:
         if tool.Ifc.get():
             return  # The current model's coordinates always take priority.
 
+        if len(tool.Project.get_project_props().links) > 1:
+            return  # Only the first link sets the origin
+
         json_filepath = self.filepath_.with_suffix(".ifc.cache.json")
         if not json_filepath.exists():
             return
@@ -1576,21 +1583,36 @@ except Exception as e:
             if (value := data.get(prop, None)) is not None:
                 setattr(gprops, prop, value)
 
+    def set_georeferencing_indicator(self) -> None:
+        if not tool.Ifc.get():
+            self.link.georeferenced = "NONE"
+            return
+        if not (crs_name := (ifcopenshell.util.geolocation.get_crs(tool.Ifc.get()) or {}).get("Name", "")):
+            self.link.georeferenced = "NONE"
+            return
+        reference = tool.Ifc.get().by_id(self.link.ifc_definition_id)
+        json_filepath = Path(reference.Location).with_suffix(".ifc.cache.json")
+        if not json_filepath.exists():
+            self.link.georeferenced = "NONE"
+            return
+        with open(json_filepath, "r") as f:
+            data = json.load(f)
+        if not data["model_is_georeferenced"]:
+            self.link.georeferenced = "NONE"
+        else:
+            self.link.georeferenced = "FULL_COMPATIBLE" if crs_name == data["model_crs"] else "NOT_COMPATIBLE"
+
 
 class ReloadLink(bpy.types.Operator):
     bl_idname = "bim.reload_link"
     bl_label = "Reload Link"
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Reload the selected file"
-    filepath: bpy.props.StringProperty()
+    link_index: bpy.props.IntProperty(name="Link Index")
 
     def execute(self, context):
-        is_abs = os.path.isabs(Path(self.filepath))
+        bpy.ops.bim.unload_link(link_index=self.link_index)
-        use_relative_path = not is_abs
+        return bpy.ops.bim.load_link(link_index=self.link_index, use_cache=False) or {"FINISHED"}
-        bpy.ops.bim.unlink_ifc(filepath=self.filepath)
-        filepath = tool.Ifc.resolve_uri(self.filepath)
-        status = bpy.ops.bim.link_ifc(filepath=filepath, use_cache=False, use_relative_path=use_relative_path)
-        return {"FINISHED"}
 
 
 class ToggleLinkSelectability(bpy.types.Operator):
@@ -1598,16 +1620,18 @@ class ToggleLinkSelectability(bpy.types.Operator):
     bl_label = "Toggle Link Selectability"
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Toggle selectability"
-    link: bpy.props.StringProperty(name="Linked IFC Filepath")
+    link_index: bpy.props.IntProperty(name="Link Index")
 
     def execute(self, context):
         props = tool.Project.get_project_props()
-        link = props.links[self.link]
+        link = props.links[self.link_index]
-        self.library_filepath = tool.Blender.ensure_blender_path_is_abs(Path(self.link).with_suffix(".ifc.cache.blend"))
+        self.library_filepath = tool.Blender.ensure_blender_path_is_abs(
+            Path(link.filepath).with_suffix(".ifc.cache.blend")
+        )
         link.is_selectable = (is_selectable := not link.is_selectable)
         for collection in self.get_linked_collections():
             collection.hide_select = not is_selectable
-        if handle := link.empty_handle:
+        if handle := tool.Project.get_link_empty_handle(link):
             handle.hide_select = not is_selectable
         return {"FINISHED"}
 
@@ -1624,13 +1648,15 @@ class ToggleLinkVisibility(bpy.types.Operator):
     bl_label = "Toggle Link Visibility"
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Toggle visibility between SOLID and WIREFRAME"
-    link: bpy.props.StringProperty(name="Linked IFC Filepath")
+    link_index: bpy.props.IntProperty(name="Link Index")
     mode: bpy.props.EnumProperty(name="Visibility Mode", items=((i, i, "") for i in ("WIREFRAME", "VISIBLE")))
 
     def execute(self, context):
         props = tool.Project.get_project_props()
-        link = props.links[self.link]
+        link = props.links[self.link_index]
-        self.library_filepath = tool.Blender.ensure_blender_path_is_abs(Path(self.link).with_suffix(".ifc.cache.blend"))
+        self.library_filepath = tool.Blender.ensure_blender_path_is_abs(
+            Path(link.filepath).with_suffix(".ifc.cache.blend")
+        )
         if self.mode == "WIREFRAME":
             self.toggle_wireframe(link)
         elif self.mode == "VISIBLE":
@@ -1652,7 +1678,7 @@ class ToggleLinkVisibility(bpy.types.Operator):
         layer_collections = tool.Blender.get_layer_collections_mapping(linked_collections)
         for layer_collection in layer_collections.values():
             layer_collection.exclude = is_hidden
-        if handle := link.empty_handle:
+        if handle := tool.Project.get_link_empty_handle(link):
             handle.hide_set(is_hidden)
 
     def get_linked_collections(self) -> list[bpy.types.Collection]:
@@ -1663,17 +1689,95 @@ class ToggleLinkVisibility(bpy.types.Operator):
         ]
 
 
+class EnableEditingLink(bpy.types.Operator):
+    bl_idname = "bim.enable_editing_link"
+    bl_label = "Enable Editing Link"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Enable editing link location"
+
+    def execute(self, context):
+        link = tool.Project.get_project_props().active_link
+        link.is_editing = True
+        tool.Geometry.unlock_object(tool.Project.get_link_empty_handle(link))
+        return {"FINISHED"}
+
+
+class DisableEditingLink(bpy.types.Operator):
+    bl_idname = "bim.disable_editing_link"
+    bl_label = "Disable Editing Link"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Disable editing link and restore to previously saved location"
+
+    def execute(self, context):
+        link = tool.Project.get_project_props().active_link
+        link.is_editing = False
+        obj = tool.Project.get_link_empty_handle(link)
+        obj.matrix_world = Matrix(tool.Project.calculate_link_matrix(link))
+        tool.Geometry.lock_object(obj)
+        return {"FINISHED"}
+
+
+class EditLink(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.edit_link"
+    bl_label = "Edit Link"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Disable editing link and restore to previously saved location"
+
+    def _execute(self, context):
+        link = tool.Project.get_project_props().active_link
+        link.is_editing = False
+        obj = tool.Project.get_link_empty_handle(link)
+        new_obj_matrix = obj.matrix_world
+
+        filepath = Path(tool.Ifc.resolve_uri(link.filepath))
+        with open(filepath.with_suffix(".ifc.cache.json"), "r") as f:
+            metadata = json.load(f)
+
+        rot = ifcopenshell.util.shape_builder.np_rotation_matrix(
+            radians(-float(metadata["model_project_north"])), 4, "Z"
+        )
+        global_matrix = rot @ np.eye(4)
+        global_matrix[:, 3][:3] = [float(o) for o in metadata["model_origin_si"].split(",")]
+
+        gprops = tool.Georeference.get_georeference_props()
+        rot = ifcopenshell.util.shape_builder.np_rotation_matrix(radians(-float(gprops.model_project_north)), 4, "Z")
+        local_matrix = rot @ np.eye(4)
+        local_matrix[:, 3][:3] = [float(o) for o in gprops.model_origin_si.split(",")]
+
+        # obj_matrix is typically calculated as:
+        # obj_matrix = np.linalg.inv(local_matrix) @ transformation @ global_matrix
+        # So let's calculate the transformation
+
+        transformed_global_matrix = local_matrix @ np.array(new_obj_matrix)
+        transformation = transformed_global_matrix @ np.linalg.inv(global_matrix)
+        if np.allclose(transformation, np.eye(4)):
+            link.has_transformation = True
+            transformation = ",".join(map(str, np.eye(4).reshape(-1)))
+        else:
+            link.has_transformation = False
+            transformation = ",".join(map(str, transformation.reshape(-1)))
+
+        if tool.Ifc.get():
+            reference = tool.Ifc.get().by_id(link.ifc_definition_id)
+            reference[1] = transformation
+        else:
+            link.transformation = transformation
+
+        obj.matrix_world = Matrix(tool.Project.calculate_link_matrix(link))
+        tool.Geometry.lock_object(obj)
+
+
 class SelectLinkHandle(bpy.types.Operator):
     bl_idname = "bim.select_link_handle"
     bl_label = "Select Link Handle"
     bl_options = {"REGISTER", "UNDO"}
     bl_description = "Select link empty object handle"
-    index: bpy.props.IntProperty(name="Link Index")
+    link_index: bpy.props.IntProperty(name="Link Index")
 
     def execute(self, context):
         props = tool.Project.get_project_props()
-        link = props.links[self.index]
+        link = props.links[self.link_index]
-        handle = link.empty_handle
+        handle = tool.Project.get_link_empty_handle(link)
         if not handle:
             self.report({"ERROR"}, "Link has no empty handle (probably it was deleted).")
             return {"CANCELLED"}
@@ -1866,7 +1970,14 @@ class LoadLinkedProject(bpy.types.Operator, ImportHelper):
         print("Processing", self.filepath)
 
         self.collection = bpy.data.collections.new("IfcProject/" + os.path.basename(self.filepath))
-        self.file = ifcopenshell.open(self.filepath)
+
+        try:
+            self.file = ifcopenshell.open(self.filepath)
+        except Exception as e:
+            self.report({"ERROR"}, f"Failed to open IFC file: {str(e)}")
+            bpy.data.collections.remove(self.collection)
+            return {"CANCELLED"}
+
         tool.Ifc.set(self.file)
         print("Finished opening")
 
@@ -1897,20 +2008,13 @@ class LoadLinkedProject(bpy.types.Operator, ImportHelper):
         if tool.Loader.settings.false_origin_mode == "MANUAL" and tool.Loader.settings.false_origin:
             tool.Loader.set_manual_blender_offset(self.file)
         elif tool.Loader.settings.false_origin_mode == "AUTOMATIC":
-            if host_model_origin_si := gprops.host_model_origin_si:
+            tool.Loader.guess_false_origin(self.file)
-                host_model_origin_si = [float(o) / self.unit_scale for o in host_model_origin_si.split(",")]
-                tool.Loader.settings.false_origin = host_model_origin_si
-                tool.Loader.settings.project_north = float(gprops.host_model_project_north)
-                tool.Loader.set_manual_blender_offset(self.file)
-            else:
-                tool.Loader.guess_false_origin(self.file)
 
         tool.Georeference.set_model_origin()
         self.json_filepath = self.filepath + ".cache.json"
         data = {
-            "host_model_origin": gprops.host_model_origin,
+            "model_is_georeferenced": gprops.model_is_georeferenced,
-            "host_model_origin_si": gprops.host_model_origin_si,
+            "model_crs": gprops.model_crs,
-            "host_model_project_north": gprops.host_model_project_north,
             "model_origin": gprops.model_origin,
             "model_origin_si": gprops.model_origin_si,
             "model_project_north": gprops.model_project_north,

src/bonsai/bonsai/bim/module/project/prop.py

@@ -16,8 +16,9 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
-import os
+import math
 from collections.abc import Generator
+from pathlib import Path
 from typing import TYPE_CHECKING, Literal, Union, assert_never, get_args
 
 import bpy
@@ -219,29 +220,62 @@ class FilterCategory(PropertyGroup):
 
 
 class Link(PropertyGroup):
-    name: StringProperty(
+    name: StringProperty(name="Name")
-        name="Name",
+    filepath: StringProperty(
+        name="Filepath",
         description="Filepath to linked .ifc file, stored in posix format (could be relative to .ifc file, not to .blend)",
     )
+    transformation: StringProperty(
+        name="Transformation",
+        description="4x4 matrix transformation as a flattened comma separated list for the linked model",
+        default="",
+    )
+    georeferenced: EnumProperty(
+        name="Georeferenced",
+        description="Georeferencing status: compatibility between host and linked model",
+        items=[
+            ("NONE", "No Georef", "Linked model has no georeferencing"),
+            ("NOT_COMPATIBLE", "Not Compatible", "Has geo data but CRS differ from host"),
+            ("FULL_COMPATIBLE", "Full Compatible", "Both CRS name and vertical datum match host"),
+        ],
+        default="NONE",
+    )
+    has_transformation: BoolProperty(
+        name="Has Transformation",
+        description="Whether there is a transformation from its global coordinates",
+        default=False,
+    )
     is_loaded: BoolProperty(name="Is Loaded", default=False)
+    is_editing: BoolProperty(name="Is Editing", description="Whether the link is being transformed", default=False)
     is_selectable: BoolProperty(name="Is Selectable", default=True)
     is_wireframe: BoolProperty(name="Is Wireframe", default=False)
     is_hidden: BoolProperty(name="Is Hidden", default=False)
     include_in_drawings: BoolProperty(name="Include in Drawings", default=True, options=set())
     empty_handle: PointerProperty(
         name="Empty Object Handle",
-        description="We use empty object handle to allow simple manipulations with a linked model (moving, scaling, rotating)",
+        description="Storage for empty handle. Used in non-IFC scenarios or temporarily during link creation",
         type=bpy.types.Object,
     )
+    ifc_definition_id: IntProperty(
+        name="IFC Definition ID",
+        description="STEP ID of the IfcDocumentReference when linked to a parent IFC project. Zero when no parent IFC exists",
+        default=0,
+    )
 
     if TYPE_CHECKING:
         name: str
+        filepath: str
+        transformation: str
+        georeferenced: Literal["NONE", "NOT_COMPATIBLE", "FULL_COMPATIBLE"]
+        has_transformation: bool
         is_loaded: bool
+        is_editing: bool
         is_selectable: bool
         is_wireframe: bool
         is_hidden: bool
         include_in_drawings: bool
         empty_handle: Union[bpy.types.Object, None]
+        ifc_definition_id: int
 
 
 class EditedObj(PropertyGroup):
@@ -424,6 +458,10 @@ class BIMProjectProperties(PropertyGroup):
     clipping_planes_active_index: bpy.props.IntProperty(min=0, default=0, max=5)
     edited_objs: bpy.props.CollectionProperty(type=EditedObj)
 
+    @property
+    def active_link(self) -> Union[Link, None]:
+        return tool.Blender.get_active_uilist_element(self.links, self.active_link_index)
+
     @property
     def active_clipping_plane(self) -> ObjProperty | None:
         return tool.Blender.get_active_uilist_element(self.clipping_planes, self.clipping_planes_active_index)

src/bonsai/bonsai/bim/module/project/ui.py

@@ -22,6 +22,7 @@ import os
 from typing import TYPE_CHECKING
 
 import bpy
+import math
 import ifcopenshell
 from bpy.types import Menu, Panel, UIList
 
@@ -30,6 +31,7 @@ import bonsai.tool as tool
 from bonsai.bim.helper import draw_attributes, prop_with_search
 from bonsai.bim.ifc import IfcStore
 from bonsai.bim.module.project.data import LinksData, ProjectData
+from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
     from bonsai.bim.module.project.prop import (
@@ -477,17 +479,27 @@ class BIM_PT_links(Panel):
 
     def draw(self, context):
         self.props = tool.Project.get_project_props()
+
         row = self.layout.row(align=True)
         row.operator("bim.link_ifc")
         if self.props.links:
-            self.layout.template_list(
+            if self.props.active_link:
-                "BIM_UL_links",
+                row = self.layout.row(align=True)
-                "",
+                row.alignment = "RIGHT"
-                self.props,
+                index = self.props.active_link_index
-                "links",
+                if self.props.active_link.is_editing:
-                self.props,
+                    row.operator("bim.edit_link", text="", icon="CHECKMARK")
-                "active_link_index",
+                    row.operator("bim.disable_editing_link", text="", icon="CANCEL")
-            )
+                else:
+                    row.operator("bim.enable_editing_link", text="", icon="GREASEPENCIL")
+                if self.props.active_link.is_loaded:
+                    row.operator("bim.select_link_handle", text="", icon="OBJECT_DATA").link_index = index
+                    row.operator("bim.unload_link", text="", icon="UNLINKED").link_index = index
+                    row.operator("bim.reload_link", text="", icon="FILE_REFRESH").link_index = index
+                else:
+                    row.operator("bim.load_link", text="", icon="LINKED").link_index = index
+                    row.operator("bim.unlink_ifc", text="", icon="X").link_index = index
+            self.layout.template_list("BIM_UL_links", "", self.props, "links", self.props, "active_link_index")
 
         if LinksData.enable_culling:
             row = self.layout.row(align=True)
@@ -607,47 +619,30 @@ class BIM_UL_links(UIList):
         active_propname,
         index,
     ):
-        if item:
+        row = layout.row(align=True)
-            row = layout.row(align=True)
+        if item.is_loaded:
-            if item.is_loaded:
+            if item.georeferenced == "NONE":
-                row.label(text=item.name)
+                row.label(text="", icon="QUESTION")
-                op = row.operator(
+            elif item.georeferenced == "NOT_COMPATIBLE":
-                    "bim.toggle_link_selectability",
+                row.label(text="", icon="ERROR")
-                    text="",
+            elif item.georeferenced == "FULL_COMPATIBLE":
-                    icon="RESTRICT_SELECT_OFF" if item.is_selectable else "RESTRICT_SELECT_ON",
+                row.label(text="", icon="WORLD")
-                    emboss=False,
+            if item.has_transformation:
-                )
+                row.label(text="", icon="OBJECT_ORIGIN")
-                op.link = item.name
+
-                op = row.operator(
+            row.label(text=item.filepath)
-                    "bim.toggle_link_visibility",
+            icon = "RESTRICT_SELECT_OFF" if item.is_selectable else "RESTRICT_SELECT_ON"
-                    text="",
+            row.operator("bim.toggle_link_selectability", text="", icon=icon, emboss=False).link_index = index
-                    icon="CUBE" if item.is_wireframe else "MESH_CUBE",
+            icon = "CUBE" if item.is_wireframe else "MESH_CUBE"
-                    emboss=False,
+            op = row.operator("bim.toggle_link_visibility", text="", icon=icon, emboss=False)
-                )
+            op.link_index = index
-                op.link = item.name
+            op.mode = "WIREFRAME"
-                op.mode = "WIREFRAME"
+            icon = "HIDE_ON" if item.is_hidden else "HIDE_OFF"
-                op = row.operator(
+            op = row.operator("bim.toggle_link_visibility", text="", icon=icon, emboss=False)
-                    "bim.toggle_link_visibility",
+            op.link_index = index
-                    text="",
+            op.mode = "VISIBLE"
-                    icon="HIDE_ON" if item.is_hidden else "HIDE_OFF",
+        else:
-                    emboss=False,
+            row.label(text=item.filepath)
-                )
-                op.link = item.name
-                op.mode = "VISIBLE"
-                op = row.operator("bim.select_link_handle", text="", icon="OBJECT_DATA")
-                op.index = index
-                op = row.operator("bim.unload_link", text="", icon="UNLINKED")
-                op.filepath = item.name
-                op = row.operator("bim.reload_link", text="", icon="FILE_REFRESH")
-                op.filepath = item.name
-            else:
-                row.prop(item, "name", text="")
-                op = row.operator("bim.select_uri_attribute", text="", icon="FILE_FOLDER")
-                op.attribute_data_path = tool.Blender.get_full_data_path(item, "name")
-                op = row.operator("bim.load_link", text="", icon="LINKED")
-                op.filepath = item.name
-                op = row.operator("bim.unlink_ifc", text="", icon="X")
-                op.filepath = item.name
 
 
 class BIM_PT_purge(Panel):

src/bonsai/bonsai/bim/operator.py

@@ -268,63 +268,45 @@ class SaveBlendMetadataFile(bpy.types.Operator):
 import bpy
 
 # Ensure all styles are loaded before attempting to remove them
-try:
+bpy.ops.bim.load_styles()
-    bpy.ops.bim.load_styles()
-except Exception:
-    pass
 
 # 1. Collect all IfcStyle material names
 ifcstyle_material_names = []
-try:
+styles_props = getattr(bpy.context.scene, "BIMStylesProperties", None)
-    styles_props = getattr(bpy.context.scene, "BIMStylesProperties", None)
+if styles_props is None and bpy.data.scenes:
-    if styles_props is None and bpy.data.scenes:
+    styles_props = getattr(bpy.data.scenes[0], "BIMStylesProperties", None)
-        styles_props = getattr(bpy.data.scenes[0], "BIMStylesProperties", None)
+if styles_props:
-    if styles_props:
+    for style in list(styles_props.styles):
-        for style in list(styles_props.styles):
+        material = getattr(style, "blender_material", None)
-            material = getattr(style, "blender_material", None)
+        if material and material.name:
-            if material and material.name:
+            ifcstyle_material_names.append(material.name)
-                ifcstyle_material_names.append(material.name)
-except Exception:
-    pass
 
 # 2. Purge IfcStore
-try:
+from bonsai.bim.ifc import IfcStore
-    from bonsai.bim.ifc import IfcStore
+IfcStore.purge()
-except ImportError:
-    IfcStore = None
-
-if IfcStore:
-    try:
-        IfcStore.purge()
-    except Exception:
-        pass
 
 # 3. Remove all collections named IfcProject*
 for collection in list(bpy.data.collections):
     if collection.name.startswith('IfcProject'):
-        try:
+        bpy.data.collections.remove(collection, do_unlink=True)
-            bpy.data.collections.remove(collection, do_unlink=True)
-        except Exception:
-            pass
 
-# 4. Purge orphaned data blocks after removing IfcProject collections
+# 4.1 Remove all collections from linked libraries (they will be recreated by bonsai)
-try:
+for collection in list(bpy.data.collections):
-    bpy.ops.outliner.orphans_purge(do_local_ids=True, do_linked_ids=True, do_recursive=True)
+    if collection.library:
-except Exception:
+        bpy.data.collections.remove(collection, do_unlink=True)
-    pass
 
-# 5. Remove all materials corresponding to the IfcStyles we collected
+# 4.2. Remove all empty objects that are collection instances for linked models
-materials_removed = 0
+for obj in list(bpy.data.objects):
-try:
+    if obj.type == 'EMPTY' and obj.instance_type == 'COLLECTION' and obj.name.startswith('IfcProject/'):
-    for mat_name in ifcstyle_material_names:
+        bpy.data.objects.remove(obj, do_unlink=True)
-        if mat_name in bpy.data.materials:
+
-            try:
+# 5. Purge orphaned data blocks after removing IfcProject collections
-                bpy.data.materials.remove(bpy.data.materials[mat_name], do_unlink=True)
+bpy.ops.outliner.orphans_purge(do_local_ids=True, do_linked_ids=True, do_recursive=True)
-                materials_removed += 1
+
-            except Exception:
+# 6. Remove all materials corresponding to the IfcStyles we collected
-                pass
+for mat_name in ifcstyle_material_names:
-except Exception:
+    if mat_name in bpy.data.materials:
-    pass
+        bpy.data.materials.remove(bpy.data.materials[mat_name], do_unlink=True)
 
 bpy.ops.wm.save_as_mainfile(filepath=r'{blendmetadata_path}')
 """

src/bonsai/bonsai/bim/ui.py

@@ -660,6 +660,10 @@ class BIM_ADDON_preferences(bpy.types.AddonPreferences):
     bsdd_load_test_dictionaries: BoolProperty(
         name="Load Test Dictionaries", description="Load dictionaries that are for testing only", default=False
     )
+    bsdd_baseurl: StringProperty(
+        name="bSDD API Base URL", description="Base URL for data dictionary API requests, e.g. https://api.bsdd.buildingsmart.org/api/",
+        default="https://api.bsdd.buildingsmart.org/api/",
+    )
     should_disable_undo_on_save: BoolProperty(
         name="Disable Undo When Saving (Faster saves, no undo for you!)", default=False
     )
@@ -972,6 +976,7 @@ class BIM_ADDON_preferences(bpy.types.AddonPreferences):
         layout.prop(self, "bsdd_load_preview_dictionaries")
         layout.prop(self, "bsdd_load_inactive_dictionaries")
         layout.prop(self, "bsdd_load_test_dictionaries")
+        layout.prop(self, "bsdd_baseurl")
 
     def draw_extras_settings(self, layout: bpy.types.UILayout, context: bpy.types.Context) -> None:
         layout.prop(self, "container_hide_show_isolate")

src/bonsai/bonsai/core/georeference.py

@@ -29,6 +29,7 @@ if TYPE_CHECKING:
 
 def add_georeferencing(georeference: type[tool.Georeference]) -> None:
     georeference.add_georeferencing()
+    georeference.set_model_origin()
 
 
 def enable_editing_georeferencing(georeference: type[tool.Georeference]) -> None:
@@ -37,8 +38,9 @@ def enable_editing_georeferencing(georeference: type[tool.Georeference]) -> None
     georeference.enable_editing()
 
 
-def remove_georeferencing(ifc: type[tool.Ifc]) -> None:
+def remove_georeferencing(ifc: type[tool.Ifc], georeference: type[tool.Georeference]) -> None:
     ifc.run("georeference.remove_georeferencing")
+    georeference.set_model_origin()
 
 
 def disable_editing_georeferencing(georeference: type[tool.Georeference]) -> None:

src/bonsai/bonsai/tool/blender.py

@@ -2165,3 +2165,13 @@ class Blender(bonsai.core.tool.Blender):
         if cls.BLENDER_5:
             return np.array(mathutils_type)
         return np.array(mathutils_type, dtype=np.float32)
+
+    @classmethod
+    def get_selected_files(
+        cls, directory: str, files: bpy.types.OperatorFileListElement, use_relative_path=False
+    ) -> list[Path]:
+        return [
+            tool.Ifc.get_uri(Path(directory) / f.name, use_relative_path=use_relative_path)
+            for f in files
+            if (Path(directory) / f.name).is_file()
+        ]

src/bonsai/bonsai/tool/bsdd.py

@@ -123,6 +123,10 @@ class Bsdd(bonsai.core.tool.Bsdd):
     @classmethod
     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)
         dicts = response.get("dictionaries") or []
         statuses = ["Active"]

src/bonsai/bonsai/tool/document.py

@@ -251,11 +251,19 @@ class Document(bonsai.core.tool.Document):
     def get_document_references(
         cls, document: ifcopenshell.entity_instance
     ) -> tuple[ifcopenshell.entity_instance, ...]:
+        # TODO: migrate to util.document and replace all instances
         """Get IfcDocumentReference.ReferencedDocuments, compatible with IFC2X3."""
         if document.file.schema == "IFC2X3":
             return document.DocumentReferences or ()
         return document.HasDocumentReferences
 
+    @classmethod
+    def get_reference_document(cls, reference: ifcopenshell.entity_instance) -> ifcopenshell.entity_instance | None:
+        # TODO: migrate to util.document and replace all instances
+        if reference.file.schema == "IFC2X3":
+            return (reference.ReferenceToDocument or (None))[0]
+        return reference.ReferencedDocument
+
     @classmethod
     def clear_active_document(cls) -> None:
         props = cls.get_document_props()

src/bonsai/bonsai/tool/drawing.py

@@ -857,9 +857,11 @@ class Drawing(bonsai.core.tool.Drawing):
     def edit_text_literals(cls, obj: bpy.types.Object, literal_attributes: dict) -> None:
         assert (element := tool.Ifc.get_entity(obj))
         assert (rep := cls.get_annotation_representation(element))
-        for literal in cls.get_text_literal(obj, return_list=True):
+        to_remove = [i for i in rep.Items if i.is_a("IfcTextLiteral")]
+        new_literals = [cls.add_literal(**a) for a in literal_attributes]
+        rep.Items = [i for i in rep.Items if not i.is_a("IfcTextLiteral")] + new_literals
+        for literal in to_remove:
             ifcopenshell.util.element.remove_deep2(tool.Ifc.get(), literal)
-        rep.Items = [cls.add_literal(**a) for a in literal_attributes]
 
     @classmethod
     def add_literal(cls, **attributes: str) -> ifcopenshell.entity_instance:

src/bonsai/bonsai/tool/georeference.py

@@ -315,6 +315,21 @@ class Georeference(bonsai.core.tool.Georeference):
             )
         return coordinates
 
+    @classmethod
+    def global2local(cls, matrix, is_specified_in_map_units: bool) -> tuple[float, float, float]:
+        matrix = ifcopenshell.util.geolocation.auto_global2local(tool.Ifc.get(), matrix, is_specified_in_map_units=is_specified_in_map_units)
+        props = cls.get_georeference_props()
+        if props.has_blender_offset:
+            matrix = ifcopenshell.util.geolocation.global2local(
+                matrix,
+                float(props.blender_offset_x),
+                float(props.blender_offset_y),
+                float(props.blender_offset_z),
+                float(props.blender_x_axis_abscissa),
+                float(props.blender_x_axis_ordinate),
+            )
+        return matrix
+
     @classmethod
     def import_plot(cls, filepath: str) -> None:
         import bmesh
@@ -385,6 +400,9 @@ class Georeference(bonsai.core.tool.Georeference):
         unit_scale = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
         gprops = tool.Georeference.get_georeference_props()
         e, n, h = cls.xyz2enh((0, 0, 0), should_return_in_map_units=False)
+        crs = ifcopenshell.util.geolocation.get_crs(tool.Ifc.get()) or {}
+        gprops.model_is_georeferenced = bool(crs)
+        gprops.model_crs = crs.get("Name", "") or ""
         gprops.model_origin = f"{e},{n},{h}"
         gprops.model_origin_si = f"{e * unit_scale},{n * unit_scale},{h * unit_scale}"
         angle = ifcopenshell.util.geolocation.get_grid_north(tool.Ifc.get())

src/bonsai/bonsai/tool/project.py

@@ -19,10 +19,14 @@
 from __future__ import annotations
 
 import os
+import json
+import math
 import shutil
+import numpy as np
 from collections import defaultdict
+from math import radians
 from pathlib import Path
-from typing import TYPE_CHECKING, NamedTuple, Optional, Union
+from typing import TYPE_CHECKING, NamedTuple, Optional
 
 import bpy
 import ifcopenshell
@@ -58,6 +62,47 @@ class Project(bonsai.core.tool.Project):
         assert (scene := bpy.context.scene)
         return scene.MeasureToolSettings  # pyright: ignore[reportAttributeAccessIssue]
 
+    @classmethod
+    def get_link_empty_handle(cls, link) -> bpy.types.Object | None:
+        if tool.Ifc.get():
+            return tool.Ifc.get_object(tool.Ifc.get().by_id(link.ifc_definition_id))
+        return link.empty_handle
+
+    @classmethod
+    def set_link_empty_handle(cls, link, empty: bpy.types.Object) -> None:
+        if tool.Ifc.get():
+            tool.Ifc.link(tool.Ifc.get().by_id(link.ifc_definition_id), empty)
+        else:
+            link.empty_handle = empty
+
+    @classmethod
+    def calculate_link_matrix(cls, link) -> None:
+        filepath = Path(tool.Ifc.resolve_uri(link.filepath))
+        with open(filepath.with_suffix(".ifc.cache.json"), "r") as f:
+            metadata = json.load(f)
+
+        rot = ifcopenshell.util.shape_builder.np_rotation_matrix(
+            radians(-float(metadata["model_project_north"])), 4, "Z"
+        )
+        global_matrix = rot @ np.eye(4)
+        global_matrix[:, 3][:3] = [float(o) for o in metadata["model_origin_si"].split(",")]
+
+        if tool.Ifc.get():
+            transformation = tool.Ifc.get().by_id(link.ifc_definition_id)[1]  # Identification
+        else:
+            transformation = link.transformation
+
+        if transformation:
+            transformation = np.fromstring(transformation, sep=",", dtype=np.float64).reshape(4, 4)
+            if not np.allclose(transformation, np.eye(4)):
+                global_matrix = transformation @ global_matrix
+
+        gprops = tool.Georeference.get_georeference_props()
+        rot = ifcopenshell.util.shape_builder.np_rotation_matrix(radians(-float(gprops.model_project_north)), 4, "Z")
+        local_matrix = rot @ np.eye(4)
+        local_matrix[:, 3][:3] = [float(o) for o in gprops.model_origin_si.split(",")]
+        return np.linalg.inv(local_matrix) @ global_matrix
+
     @classmethod
     def append_all_types_from_template(cls, template: str) -> None:
         # TODO refactor
@@ -249,68 +294,32 @@ class Project(bonsai.core.tool.Project):
         tool.Root.reload_grid_decorator()
 
     @classmethod
-    def get_linked_models_document(cls) -> Union[ifcopenshell.entity_instance, None]:
+    def get_linked_models_documents(cls) -> dict[str, ifcopenshell.entity_instance]:
-        for document in tool.Ifc.get().by_type("IfcDocumentInformation"):
+        linked_docs = {}
-            if document.Name == "BBIM_Linked_Models":
+        for doc in tool.Ifc.get().by_type("IfcDocumentInformation"):
-                return document
+            if doc.Scope == "LINKED_MODEL":
+                for reference in tool.Drawing.get_document_references(doc):
+                    linked_docs[Path(reference.Location).as_posix()] = doc
+                    break
+        return linked_docs
 
     @classmethod
     def load_linked_models_from_ifc(cls) -> None:
         links = tool.Project.get_project_props().links
         links.clear()
-        links_document = cls.get_linked_models_document()
+        for doc in tool.Ifc.get().by_type("IfcDocumentInformation"):
-        if not links_document:
+            if doc.Scope != "LINKED_MODEL":
-            return
+                continue
-
+            for reference in tool.Drawing.get_document_references(doc):
-        references = tool.Document.get_document_references(links_document)
+                filepath = reference.Location
-        if not references:
+                link = links.add()
-            return
+                link.name = filepath
-
+                link.filepath = filepath
-        for reference in references:
+                link.ifc_definition_id = reference.id()
-            link = links.add()
+                link.has_transformation = False
-            link.name = reference.Location
+                if reference[1]:
-
+                    m = np.fromstring(reference[1], sep=",", dtype=np.float64).reshape(4, 4)
-    @classmethod
+                    link.has_transformation = not np.allclose(m, np.eye(4))
-    def save_linked_models_to_ifc(cls) -> None:
-        ifc_file = tool.Ifc.get()
-        links = tool.Project.get_project_props().links
-        filepaths: set[Path] = set()
-        for link in links:
-            filepaths.add(Path(link.name))
-
-        links_document = cls.get_linked_models_document()
-
-        if not filepaths and links_document is None:
-            return
-
-        paths_to_add = filepaths.copy()
-        references_to_remove: list[ifcopenshell.entity_instance] = []
-        if links_document:
-            references = tool.Document.get_document_references(links_document)
-            for reference in references:
-                # I guess got corrupted by the user.
-                if not (location := reference.Location):
-                    references_to_remove.remove(reference)
-                    continue
-                path = Path(location)
-                if path in paths_to_add:
-                    paths_to_add.remove(path)
-                else:
-                    references_to_remove.append(reference)
-
-        if paths_to_add:
-            if links_document is None:
-                links_document = ifcopenshell.api.document.add_information(ifc_file)
-                links_document.Name = "BBIM_Linked_Models"
-                links_document.Description = "Bonsai internal document containing references to currently linked models"
-
-            for path in paths_to_add:
-                reference = ifcopenshell.api.document.add_reference(ifc_file, links_document)
-                reference.Location = path.as_posix()
-
-        if references_to_remove:
-            for reference in references_to_remove:
-                ifcopenshell.api.document.remove_reference(ifc_file, reference)
 
     @classmethod
     def get_project_library_elements(

src/bonsai/bonsai/tool/snap.py

@@ -118,14 +118,10 @@ class Snap(bonsai.core.tool.Snap):
     def get_angle_snap_value(cls, context: bpy.types.Context) -> float:
         """Get the angle snap increment from Blender's tool settings.
 
-        Uses snap_angle_increment_3d (Blender 5.0+) or snap_angle_increment (Blender 4.x).
-
         :param context: Blender context
         :return: Angle snap increment in degrees
         """
-        if bpy.app.version >= (5, 0, 0):
+        return math.degrees(context.scene.tool_settings.snap_angle_increment_3d)
-            return math.degrees(context.scene.tool_settings.snap_angle_increment_3d)
-        return math.degrees(context.scene.tool_settings.snap_angle_increment)
 
     @classmethod
     def get_snap_points_on_raycasted_face(cls, context, event, obj, face_index):

src/bonsai/test/bim/bootstrap.py

@@ -34,6 +34,7 @@ from bonsai.bim.ifc import IfcStore
 
 # Monkey-patch webbrowser opening since we want to test headlessly
 webbrowser.open = lambda x: True
+tool.Drawing.open_with_user_command = lambda x, y: True
 
 
 variables = {"cwd": os.getcwd(), "ifc": "IfcStore.get_file()"}

src/bonsai/test/bim/feature/drawing.feature

@@ -3,12 +3,6 @@ Feature: Drawing
 
 Scenario: Duplicate drawing
     Given an empty IFC project
-    And I add a cube
-    And the object "Cube" is selected
-    And I look at the "Class" panel
-    And I set the "Products" property to "IfcElement"
-    And I set the "Class" property to "IfcWall"
-    And I click "Assign IFC Class"
     And I save IFC project
     And I look at the "Drawings" panel
     And I click "IMPORT"
@@ -315,3 +309,10 @@ Scenario: Create sheet - with a drawing added to it
     And I click "IMAGE_PLANE"
     When I click "OUTPUT"
     Then the file "{ifc_dir}/sheets/A01 - UNTITLED.svg" should contain "IfcWall"
+
+Scenario: Add reference image
+    Given an empty IFC project
+    And I save IFC project
+    When I press "bim.add_reference_image(filepath='{cwd}/test/files/image.jpg')"
+    Then the object "IfcAnnotation/image" exists
+    And the object "IfcAnnotation/image" dimensions are "1.0,0.565,0."

src/bonsai/test/bim/feature/project.feature

@@ -677,31 +677,43 @@ Scenario: Load project elements - all georeferencing coordinate situations with
     And the object "IfcActuator/J" has a vertex at "10.366,3.813,-1"
     And the object "IfcActuator/J" has a vertex at "12.298,4.331,-1"
 
-Scenario: Link IFC
+Scenario: Link IFC - from an empty IFC project
     Given an empty IFC project
-    When I link IFC project from "{cwd}/test/files/basic.ifc"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/basic.ifc')"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_loaded" is "True"
     And the collection "IfcProject/basic.ifc" exists
     And the object "Chunk" exists
     And the object "Chunk" is placed in the collection "IfcProject/basic.ifc"
 
-Scenario: Link IFC - disabled false origin mode
-    Given an empty IFC project
-    # Not currently possible via UI
-    And I set "scene.BIMProjectProperties.distance_limit" to "5"
-    And I set "scene.BIMProjectProperties.false_origin_mode" to "DISABLED"
-    When I link IFC project from "{cwd}/test/files/geolocation.ifc"
-    Then the object "Chunk" exists
-    And the object "Chunk" has a vertex at "2,2,-1"
-    And the object "Chunk" has a vertex at "9,-1,-1"
-    And the object "Chunk" has a vertex at "17,4,-1"
-
 Scenario: Link IFC - from an empty IFC project - automatic false origin mode (0,0,0 will be the false origin)
     Given an empty IFC project
     # Not currently possible via UI
     And I set "scene.BIMProjectProperties.distance_limit" to "5"
     And I set "scene.BIMProjectProperties.false_origin_mode" to "AUTOMATIC"
-    When I link IFC project from "{cwd}/test/files/geolocation.ifc"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
+    Then the object "Chunk" exists
+    And the object "Chunk" has a vertex at "2,2,-1"
+    And the object "Chunk" has a vertex at "9,-1,-1"
+    And the object "Chunk" has a vertex at "17,4,-1"
+
+Scenario: Link IFC - from an empty IFC project - manual false origin mode
+    Given an empty IFC project
+    # Not currently possible via UI
+    And I set "scene.BIMProjectProperties.distance_limit" to "5"
+    And I set "scene.BIMProjectProperties.false_origin_mode" to "MANUAL"
+    And I set "scene.BIMProjectProperties.false_origin" to "10000,0,0"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
+    Then the object "Chunk" exists
+    And the object "Chunk" has a vertex at "2,2,-1"
+    And the object "Chunk" has a vertex at "9,-1,-1"
+    And the object "Chunk" has a vertex at "17,4,-1"
+
+Scenario: Link IFC - from an empty IFC project - disabled false origin mode
+    Given an empty IFC project
+    # Not currently possible via UI
+    And I set "scene.BIMProjectProperties.distance_limit" to "5"
+    And I set "scene.BIMProjectProperties.false_origin_mode" to "DISABLED"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
     Then the object "Chunk" exists
     And the object "Chunk" has a vertex at "2,2,-1"
     And the object "Chunk" has a vertex at "9,-1,-1"
@@ -712,31 +724,42 @@ Scenario: Link IFC - from an empty Blender session - automatic false origin mode
     # Not currently possible via UI
     And I set "scene.BIMProjectProperties.distance_limit" to "5"
     And I set "scene.BIMProjectProperties.false_origin_mode" to "AUTOMATIC"
-    When I link IFC project from "{cwd}/test/files/geolocation.ifc"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
     Then the object "Chunk" exists
     And the object "Chunk" has a vertex at "-11,-2,0"
     And the object "Chunk" has a vertex at "-4,-5,0"
     And the object "Chunk" has a vertex at "4,0,0"
 
-Scenario: Link IFC - manual false origin mode
+Scenario: Link IFC - from an empty Blender session - manual false origin mode
     Given an empty Blender session
     # Not currently possible via UI
     And I set "scene.BIMProjectProperties.distance_limit" to "5"
     And I set "scene.BIMProjectProperties.false_origin_mode" to "MANUAL"
     And I set "scene.BIMProjectProperties.false_origin" to "10000,0,0"
-    When I link IFC project from "{cwd}/test/files/geolocation.ifc"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
     Then the object "Chunk" exists
     And the object "Chunk" has a vertex at "-8,2,-1"
     And the object "Chunk" has a vertex at "-1,-1,-1"
     And the object "Chunk" has a vertex at "7,4,-1"
 
-Scenario: Link IFC - automatic false origin mode - two different false origins and project norths - grid north is up because we start with geolocation.ifc
+Scenario: Link IFC - from an empty Blender session - disabled false origin mode
+    Given an empty Blender session
+    # Not currently possible via UI
+    And I set "scene.BIMProjectProperties.distance_limit" to "5"
+    And I set "scene.BIMProjectProperties.false_origin_mode" to "DISABLED"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
+    Then the object "Chunk" exists
+    And the object "Chunk" has a vertex at "2,2,-1"
+    And the object "Chunk" has a vertex at "9,-1,-1"
+    And the object "Chunk" has a vertex at "17,4,-1"
+
+Scenario: Link IFC - from an empty Blender session - automatic false origin mode - two different false origins and project norths - grid north is up because we start with geolocation.ifc
     Given an empty Blender session
     # Not currently possible via UI
     And I set "scene.BIMProjectProperties.distance_limit" to "5"
     And I set "scene.BIMProjectProperties.false_origin_mode" to "AUTOMATIC"
-    When I link IFC project from "{cwd}/test/files/geolocation.ifc"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
-    And I link IFC project from "{cwd}/test/files/geolocation-mapconversion-angle.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation-mapconversion-angle.ifc', use_cache=False)"
     Then the object "Col:IfcProject/geolocation.ifc:Chunk" exists
     And the object "Col:IfcProject/geolocation-mapconversion-angle.ifc:Chunk" exists
     And the object "Col:IfcProject/geolocation.ifc:Chunk" has a vertex at "-11,-2,0"
@@ -746,13 +769,13 @@ Scenario: Link IFC - automatic false origin mode - two different false origins a
     And the object "Col:IfcProject/geolocation-mapconversion-angle.ifc:Chunk" has a vertex at "9.294,-9.366,0"
     And the object "Col:IfcProject/geolocation-mapconversion-angle.ifc:Chunk" has a vertex at "18.722,-9.036,0"
 
-Scenario: Link IFC - automatic false origin mode - two different false origins and project norths - project north is up because we start with geolocation-mapconversion-angle.ifc
+Scenario: Link IFC - from an empty Blender session - automatic false origin mode - two different false origins and project norths - project north is up because we start with geolocation-mapconversion-angle.ifc
     Given an empty Blender session
     # Not currently possible via UI
     And I set "scene.BIMProjectProperties.distance_limit" to "5"
     And I set "scene.BIMProjectProperties.false_origin_mode" to "AUTOMATIC"
-    When I link IFC project from "{cwd}/test/files/geolocation-mapconversion-angle.ifc"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation-mapconversion-angle.ifc', use_cache=False)"
-    And I link IFC project from "{cwd}/test/files/geolocation.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation.ifc', use_cache=False)"
     Then the object "Col:IfcProject/geolocation.ifc:Chunk" exists
     And the object "Col:IfcProject/geolocation-mapconversion-angle.ifc:Chunk" exists
     And the object "Col:IfcProject/geolocation-mapconversion-angle.ifc:Chunk" has a vertex at "-11,-2,0"
@@ -762,14 +785,14 @@ Scenario: Link IFC - automatic false origin mode - two different false origins a
     And the object "Col:IfcProject/geolocation.ifc:Chunk" has a vertex at "-17.696,-7.866,0"
     And the object "Col:IfcProject/geolocation.ifc:Chunk" has a vertex at "-13.268,0.464,0"
 
-Scenario: Link IFC - automatic false origin mode - three identical false origins but different project and map units
+Scenario: Link IFC - from an empty Blender session - automatic false origin mode - three identical false origins but different project and map units
     Given an empty Blender session
     # Not currently possible via UI
     And I set "scene.BIMProjectProperties.distance_limit" to "5"
     And I set "scene.BIMProjectProperties.false_origin_mode" to "AUTOMATIC"
-    When I link IFC project from "{cwd}/test/files/geolocation-unit1.ifc"
+    When I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation-unit1.ifc', use_cache=False)"
-    And I link IFC project from "{cwd}/test/files/geolocation-unit2.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation-unit2.ifc', use_cache=False)"
-    And I link IFC project from "{cwd}/test/files/geolocation-unit3.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/geolocation-unit3.ifc', use_cache=False)"
     Then the object "Col:IfcProject/geolocation-unit1.ifc:Chunk" exists
     And the object "Col:IfcProject/geolocation-unit2.ifc:Chunk" exists
     And the object "Col:IfcProject/geolocation-unit3.ifc:Chunk" exists
@@ -779,54 +802,54 @@ Scenario: Link IFC - automatic false origin mode - three identical false origins
 
 Scenario: Toggle link visibility - wireframe mode
     Given an empty IFC project
-    And I link IFC project from "{cwd}/test/files/basic.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/basic.ifc')"
-    When I press "bim.toggle_link_visibility(link='{cwd}/test/files/basic.ifc', mode='WIREFRAME')"
+    When I press "bim.toggle_link_visibility(link_index=0, mode='WIREFRAME')"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_wireframe" is "True"
     And the object "Chunk" should display as "WIRE"
-    When I press "bim.toggle_link_visibility(link='{cwd}/test/files/basic.ifc', mode='WIREFRAME')"
+    When I press "bim.toggle_link_visibility(link_index=0, mode='WIREFRAME')"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_wireframe" is "False"
     And the object "Chunk" should display as "TEXTURED"
 
 Scenario: Toggle link selectability
     Given an empty IFC project
-    And I link IFC project from "{cwd}/test/files/basic.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/basic.ifc')"
-    When I press "bim.toggle_link_selectability(link='{cwd}/test/files/basic.ifc')"
+    When I press "bim.toggle_link_selectability(link_index=0)"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_selectable" is "False"
     And the collection "IfcProject/basic.ifc" is unselectable
-    When I press "bim.toggle_link_selectability(link='{cwd}/test/files/basic.ifc')"
+    When I press "bim.toggle_link_selectability(link_index=0)"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_selectable" is "True"
     And the collection "IfcProject/basic.ifc" is selectable
 
 Scenario: Toggle link visibility - visible mode
     Given an empty IFC project
-    And I link IFC project from "{cwd}/test/files/basic.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/basic.ifc')"
-    When I press "bim.toggle_link_visibility(link='{cwd}/test/files/basic.ifc', mode='VISIBLE')"
+    When I press "bim.toggle_link_visibility(link_index=0, mode='VISIBLE')"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_hidden" is "True"
     And the object "IfcProject/basic.ifc" is not visible
-    When I press "bim.toggle_link_visibility(link='{cwd}/test/files/basic.ifc', mode='VISIBLE')"
+    When I press "bim.toggle_link_visibility(link_index=0, mode='VISIBLE')"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_hidden" is "False"
     And the object "IfcProject/basic.ifc" is visible
 
 Scenario: Unload link
     Given an empty Blender session
-    And I link IFC project from "{cwd}/test/files/basic.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/basic.ifc')"
-    When I press "bim.unload_link(filepath='{cwd}/test/files/basic.ifc')"
+    When I press "bim.unload_link(link_index=0)"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_loaded" is "False"
     And the collection "IfcProject/basic.ifc" does not exist
 
 Scenario: Load link
     Given an empty Blender session
-    And I link IFC project from "{cwd}/test/files/basic.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/basic.ifc')"
-    And I press "bim.unload_link(filepath='{cwd}/test/files/basic.ifc')"
+    And I press "bim.unload_link(link_index=0)"
-    When I press "bim.load_link(filepath='{cwd}/test/files/basic.ifc')"
+    When I press "bim.load_link(link_index=0)"
     Then "scene.BIMProjectProperties.links['{cwd}/test/files/basic.ifc'].is_loaded" is "True"
     And the object "IfcProject/basic.ifc" exists
 
 Scenario: Unlink IFC
     Given an empty Blender session
-    And I link IFC project from "{cwd}/test/files/basic.ifc"
+    And I press "bim.link_ifc(filepath='{cwd}/test/files/basic.ifc')"
-    And I press "bim.unload_link(filepath='{cwd}/test/files/basic.ifc')"
+    And I press "bim.unload_link(link_index=0)"
-    When I press "bim.unlink_ifc(filepath='{cwd}/test/files/basic.ifc')"
+    When I press "bim.unlink_ifc(link_index=0)"
     Then "scene.BIMProjectProperties.links.get('{cwd}/test/files/basic.ifc')" is "None"
     And "scene.collection.children.get('IfcProject/basic.ifc')" is "None"
     And the object "Chunk" does not exist

src/bonsai/test/bim/test_feature.py

@@ -70,10 +70,7 @@ Can be useful for debugging, but has caveats - can't use ``wm.read_homefile``
 as resets the ``bpy.context`` and some it's members become `None`.
 """
 
-TMP = Path.cwd() / "test/files/temp"
+TMP = Path(f"{variables['cwd']}/test/files/temp")
-TEST_FILES_DIR = Path.cwd() / "test/files"
-
-CLEAN_LINKED_FILES_CACHE = False
 
 EPSET_DRAWING = Path.cwd() / "bonsai/bim/data/pset/EPset_Drawing.ifc"
 EPSET_DRAWING_BYTES = EPSET_DRAWING.read_bytes()
@@ -283,6 +280,8 @@ def create_ui_name_cache():
         try:
             panel_type = getattr(bpy.types, bl_idname)
             if panel_type.bl_rna.base.name == "Panel":
+                if "_tab_" in panel_type.bl_idname:
+                    continue  # Tab panels are just groups and not relevant in testing
                 ui_name_cache[panel_type.bl_label] = panel_type.bl_idname
             elif panel_type.bl_rna.base.name == "Operator":
                 ui_name_cache[panel_type.bl_label] = bl_idname
@@ -311,25 +310,6 @@ def vectors_are_equal(v1, v2):
     return all(is_x(v1[i], v2[i]) for i in range(len(v1)))
 
 
-@pytest.fixture(scope="function", autouse=True)
-def run_for_each_test() -> Generator[None]:
-    # Code before this runs before each test
-    yield
-    # Code after this runs after each test
-
-    global CLEAN_LINKED_FILES_CACHE
-    if CLEAN_LINKED_FILES_CACHE:
-        for filepath in TEST_FILES_DIR.glob("*.ifc.cache.*"):
-            filepath.unlink()
-        CLEAN_LINKED_FILES_CACHE = False
-
-    # pset_template tests are editing EPset_Drawing.ifc, so we need to restore it.
-    global RELOAD_EPSET_DRAWING
-    if RELOAD_EPSET_DRAWING:
-        EPSET_DRAWING.write_bytes(EPSET_DRAWING_BYTES)
-        RELOAD_EPSET_DRAWING = False
-
-
 @given("an untestable scenario")
 def an_untestable_scenario():
     pass
@@ -384,16 +364,6 @@ def saving_ifc_project() -> None:
     tool.Project.save_test_project()
 
 
-@given(parsers.parse('I link IFC project from "{filepath}"'))
-@when(parsers.parse('I link IFC project from "{filepath}"'))
-@then(parsers.parse('I link IFC project from "{filepath}"'))
-def i_link_ifc_project_from_filepath(filepath: str) -> None:
-    global CLEAN_LINKED_FILES_CACHE
-    filepath = replace_variables(filepath)
-    CLEAN_LINKED_FILES_CACHE = True
-    bpy.ops.bim.link_ifc(filepath=filepath, use_cache=False)
-
-
 @given("the Brickschema is stubbed")
 def the_brickschema_is_stubbed():
     # This makes things run faster since we don't need to load the entire brick schema
@@ -1587,10 +1557,19 @@ def the_object_name_has_a_vertex_at_location(name, location):
     is_pass = False
     target = Vector([float(co) for co in location.split(",")])
     verts = []
-    for v in obj.data.vertices:
+    depsgraph = bpy.context.evaluated_depsgraph_get()
-        verts.append(obj.matrix_world @ v.co)
+    obj_eval = obj.evaluated_get(depsgraph)
-        if (verts[-1] - target).length < 0.001:
+    mesh = obj_eval.to_mesh(preserve_all_data_layers=False, depsgraph=depsgraph)
-            is_pass = True
+    try:
+        for inst in depsgraph.object_instances:
+            if inst.object.original is obj:
+                mw = inst.matrix_world
+                for i, v in enumerate(mesh.vertices):
+                    verts.append(mw @ v.co)
+                    if (verts[-1] - target).length < 0.001:
+                        is_pass = True
+    finally:
+        obj_eval.to_mesh_clear()
     assert is_pass, f"No verts found at {location}: {verts}"
 
 

src/bonsai/test/tool/test_blender.py

@@ -24,8 +24,10 @@ import pytest
 
 import bonsai.core.tool
 import bonsai.tool as tool
+import tempfile
 from bonsai.tool.blender import Blender as subject
 from test.bim.bootstrap import NewFile
+from pathlib import Path
 
 if TYPE_CHECKING:
     import bpy.stub_internal.rna_enums as rna_enums
@@ -110,3 +112,35 @@ class TestBlenderErrorMessageExtraction(NewFile):
             assert error_reports == []
 
         bpy.utils.unregister_class(OBJECT_OT_test_fail_operator)
+
+
+class TestGetSelectedFiles(NewFile):
+    def test_get_a_single_file(self) -> None:
+        with tempfile.NamedTemporaryFile() as f:
+            file = type("", (object,), {"name": f.name})()
+            assert subject.get_selected_files(Path(f.name).parent, [file]) == [f.name]
+
+    def test_get_multiple_files(self) -> None:
+        with tempfile.NamedTemporaryFile() as f:
+            with tempfile.NamedTemporaryFile() as g:
+                file = type("", (object,), {"name": f.name})()
+                file2 = type("", (object,), {"name": g.name})()
+                assert subject.get_selected_files(Path(f.name).parent, [file, file2]) == [f.name, g.name]
+
+    def test_exclude_directories(self) -> None:
+        with tempfile.NamedTemporaryFile() as f:
+            with tempfile.TemporaryDirectory() as d:
+                file = type("", (object,), {"name": f.name})()
+                directory = type("", (object,), {"name": d})()
+                assert subject.get_selected_files(Path(f.name).parent, [file, directory]) == [f.name]
+
+    def test_get_relative_paths(self) -> None:
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            base_path = Path(tmp_dir)
+            with tempfile.NamedTemporaryFile(dir=tmp_dir, suffix=".ifc") as f:
+                tool.Ifc.set_path(str(f.name))
+                with tempfile.NamedTemporaryFile(dir=tmp_dir) as g:
+                    file = type("", (object,), {"name": g.name})
+                    assert subject.get_selected_files(Path(g.name).parent, [file], use_relative_path=True) == [
+                        Path(g.name).name
+                    ]

src/bonsai/test/tool/test_drawing.py

@@ -21,6 +21,7 @@ import xml.etree.ElementTree as ET
 from pathlib import Path
 
 import bpy
+import pytest
 import ifcopenshell
 import ifcopenshell.api.drawing
 import ifcopenshell.api.group
@@ -31,6 +32,7 @@ import ifcopenshell.util.element
 import mathutils
 import numpy as np
 from mathutils import Vector
+from ifcopenshell.util.shape_builder import ShapeBuilder
 
 import bonsai.core.tool
 import bonsai.tool as tool
@@ -150,6 +152,34 @@ class TestDisableEditingSheets(NewFile):
         assert props.is_editing_sheets == False
 
 
+class TestEditTextLiterals(NewFile):
+    def test_run(self):
+        ifc = ifcopenshell.file()
+        tool.Ifc.set(ifc)
+        obj = bpy.data.objects.new("Object", None)
+        element = ifc.createIfcAnnotation()
+        element.Representation = ifc.createIfcProductDefinitionShape()
+        context = ifc.createIfcGeometricRepresentationSubContext(ContextType="Plan", ContextIdentifier="Annotation")
+        item = ifc.createIfcTextLiteralWithExtent(Literal="Literal", Path="RIGHT", BoxAlignment="bottom-left")
+        builder = ShapeBuilder(tool.Ifc.get())
+        polyline = builder.polyline([(0.,0.,0.), (1.,0.,0.)])
+        representation = ifc.createIfcShapeRepresentation(ContextOfItems=context, Items=[item, polyline])
+        element.Representation.Representations = [representation]
+        tool.Ifc.link(element, obj)
+        literal_attributes = [
+            {
+                "Literal": "Foo",
+                "Path": "RIGHT",
+                "BoxAlignment": "bottom-left",
+            }
+        ]
+        subject.edit_text_literals(obj, literal_attributes)
+        assert len(ifc.by_type("IfcTextLiteralWithExtent")) == 1
+        literal = ifc.by_type("IfcTextLiteralWithExtent")[0]
+        assert literal in representation.Items
+        assert literal.Literal == "Foo"
+
+
 class TestDisableEditingText(NewFile):
     def test_run(self):
         obj = bpy.data.objects.new("Object", None)
@@ -908,7 +938,7 @@ class TestAddReferenceImage(NewFile):
 
         obj = bpy.data.objects["IfcAnnotation/image"]
         assert obj is not None
-        assert tool.Cad.are_vectors_equal(obj.dimensions, Vector((3.53982, 2.0, 0.0)))
+        assert tool.Cad.are_vectors_equal(obj.dimensions, Vector((1.0, 0.565, 0.0)))
 
         material = obj.active_material
         assert material
@@ -928,71 +958,3 @@ class TestAddReferenceImage(NewFile):
 
         uv_node = material_nodes["Texture Coordinate"]
         assert len(uv_node.outputs["Generated"].links[:]) == 1
-
-
-class TestAddReference(NewFile):
-    def test_add_single_reference(self):
-        """Test adding a single reference file (backward compatibility)"""
-        bpy.ops.bim.create_project()
-        ifc_path = Path("test/files/temp/test.ifc").absolute()
-        bpy.ops.bim.save_project(filepath=str(ifc_path), should_save_as=True)
-
-        # Create a temporary SVG file
-        svg_path = Path("test/files/temp/reference.svg").absolute()
-        svg_path.parent.mkdir(parents=True, exist_ok=True)
-        with open(svg_path, "w") as f:
-            f.write('<svg xmlns="http://www.w3.org/2000/svg"></svg>')
-
-        try:
-            # Add single reference
-            bpy.ops.bim.add_reference(filepath=str(svg_path))
-
-            # Verify reference was added
-            ifc = tool.Ifc.get()
-            references = [doc for doc in ifc.by_type("IfcDocumentInformation") if doc.Scope == "REFERENCE"]
-            assert len(references) == 1
-            assert references[0].Name == "reference"
-        finally:
-            # Cleanup
-            if svg_path.exists():
-                svg_path.unlink()
-
-    def test_add_multiple_references(self):
-        """Test adding multiple reference files at once"""
-        bpy.ops.bim.create_project()
-        ifc_path = Path("test/files/temp/test.ifc").absolute()
-        bpy.ops.bim.save_project(filepath=str(ifc_path), should_save_as=True)
-
-        # Create temporary SVG files
-        temp_dir = Path("test/files/temp").absolute()
-        temp_dir.mkdir(parents=True, exist_ok=True)
-
-        svg_files = []
-        for i in range(3):
-            svg_path = temp_dir / f"reference_{i}.svg"
-            with open(svg_path, "w") as f:
-                f.write('<svg xmlns="http://www.w3.org/2000/svg"></svg>')
-            svg_files.append(svg_path)
-
-        try:
-            # Test by directly calling core.add_document multiple times
-            # (simulating what the operator does with multiple files)
-            ifc = tool.Ifc.get()
-            for svg_file in svg_files:
-                uri = tool.Ifc.get_uri(str(svg_file), use_relative_path=True)
-                from bonsai.bim import core
-
-                core.drawing.add_document(tool.Ifc, tool.Drawing, "REFERENCE", uri=uri)
-
-            # Verify all references were added
-            references = [doc for doc in ifc.by_type("IfcDocumentInformation") if doc.Scope == "REFERENCE"]
-            assert len(references) == 3
-
-            reference_names = {ref.Name for ref in references}
-            expected_names = {f"reference_{i}" for i in range(3)}
-            assert reference_names == expected_names
-        finally:
-            # Cleanup
-            for svg_file in svg_files:
-                if svg_file.exists():
-                    svg_file.unlink()

src/bonsai/test/tool/test_project.py

@@ -16,9 +16,12 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+import json
 import contextlib
 import tempfile
+import numpy as np
 from pathlib import Path
+from tempfile import NamedTemporaryFile
 
 import bpy
 import ifcopenshell
@@ -263,7 +266,7 @@ class TestLoadLinkedModels(NewFile):
         props = tool.Project.get_project_props()
         ifcopenshell.api.root.create_entity(ifc, "IfcProject")
         document = ifcopenshell.api.document.add_information(ifc)
-        document.Name = "BBIM_Linked_Models"
+        document.Name = "X"
         tool.Ifc.set(ifc)
         subject.load_linked_models_from_ifc()
         assert len(props.links) == 0
@@ -273,86 +276,81 @@ class TestLoadLinkedModels(NewFile):
         props = tool.Project.get_project_props()
         ifcopenshell.api.root.create_entity(ifc, "IfcProject")
         document = ifcopenshell.api.document.add_information(ifc)
-        document.Name = "BBIM_Linked_Models"
+        document.Scope = "LINKED_MODEL"
         reference = ifcopenshell.api.document.add_reference(ifc, document)
-        linked_model_path = "test.ifc"
+        reference.Location = "test.ifc"
-        reference.Location = linked_model_path
+        reference.Identification = ""
+        reference2 = ifcopenshell.api.document.add_reference(ifc, document)
+        reference2.Location = "test2.ifc"
+        reference2.Identification = "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16"
         tool.Ifc.set(ifc)
         subject.load_linked_models_from_ifc()
-        assert len(props.links) == 1
+        assert len(props.links) == 2
-        assert props.links[0].name == linked_model_path
+        assert props.links[0].name == "test.ifc"
+        assert props.links[0].ifc_definition_id == reference.id()
+        assert props.links[0].has_transformation is False
+        assert props.links[1].name == "test2.ifc"
+        assert props.links[1].ifc_definition_id == reference2.id()
+        assert props.links[1].has_transformation is True
 
 
-class TestSaveLinkedModelsToIfc(NewFile):
+class TestCalculateLinkMatrix(NewFile):
-    def test_save_linked_models_to_ifc_no_links(self):
+    def test_linking_a_model_without_an_offset_to_our_session_with_no_offset(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        subject.save_linked_models_to_ifc()
-        assert len(ifc.by_type("IfcDocumentInformation")) == 0
-        assert len(ifc.by_type("IfcDocumentReference")) == 0
-
-    def test_save_linked_models_to_ifc_paths_to_add(self):
-        ifc = ifcopenshell.file()
-        ifcopenshell.api.root.create_entity(ifc, "IfcProject")
         props = tool.Project.get_project_props()
-        link = props.links.add()
+        gprops = tool.Georeference.get_georeference_props()
-        linked_model_path = "test.ifc"
+        with NamedTemporaryFile(suffix=".ifc.cache.json", mode="w", delete=True) as tmp:
-        link.name = linked_model_path
+            link = props.links.add()
-        tool.Ifc.set(ifc)
+            link.filepath = tmp.name.replace(".ifc.cache.json", ".ifc")
-        subject.save_linked_models_to_ifc()
+            json.dump({"model_project_north": "0", "model_origin_si": "0,0,0"}, tmp)
-        assert len(documents := ifc.by_type("IfcDocumentInformation")) == 1
+            tmp.flush()
-        assert documents[0].Name == "BBIM_Linked_Models"
+            gprops.model_project_north = "0"
-        assert len(references := ifc.by_type("IfcDocumentReference")) == 1
+            gprops.model_origin_si = "0,0,0"
-        assert references[0].Location == linked_model_path
+            assert np.allclose(subject.calculate_link_matrix(link), np.eye(4))
 
-    def test_save_linked_models_to_ifc_already_created_references(self):
+    def test_linking_an_offset_model_to_our_session_with_no_offset(self):
-        ifc = ifcopenshell.file()
+        props = tool.Project.get_project_props()
-        links = tool.Project.get_project_props().links
+        gprops = tool.Georeference.get_georeference_props()
-        ifcopenshell.api.root.create_entity(ifc, "IfcProject")
+        with NamedTemporaryFile(suffix=".ifc.cache.json", mode="w", delete=True) as tmp:
+            link = props.links.add()
+            link.filepath = tmp.name.replace(".ifc.cache.json", ".ifc")
+            json.dump({"model_project_north": "0", "model_origin_si": "5,0,0"}, tmp)
+            tmp.flush()
+            gprops.model_project_north = "0"
+            gprops.model_origin_si = "0,0,0"
+            m = np.eye(4)
+            m[0][3] = 5
+            assert np.allclose(subject.calculate_link_matrix(link), m)
 
-        document = ifcopenshell.api.document.add_information(ifc)
+    def test_linking_an_offset_model_to_our_session_with_offset(self):
-        document.Name = "BBIM_Linked_Models"
+        props = tool.Project.get_project_props()
-        document_id = document.id()
+        gprops = tool.Georeference.get_georeference_props()
-        reference = ifcopenshell.api.document.add_reference(ifc, document)
+        with NamedTemporaryFile(suffix=".ifc.cache.json", mode="w", delete=True) as tmp:
-        linked_model_path = "test.ifc"
+            link = props.links.add()
-        reference.Location = linked_model_path
+            link.filepath = tmp.name.replace(".ifc.cache.json", ".ifc")
-        reference_id = reference.id()
+            json.dump({"model_project_north": "0", "model_origin_si": "5,0,0"}, tmp)
+            tmp.flush()
+            gprops.model_project_north = "0"
+            gprops.model_origin_si = "2,0,0"
+            m = np.eye(4)
+            m[0][3] = 3
+            assert np.allclose(subject.calculate_link_matrix(link), m)
 
-        link = links.add()
+    def test_linking_an_offset_model_to_our_session_with_offset_and_transformation(self):
-        linked_model_path = "test.ifc"
+        props = tool.Project.get_project_props()
-        link.name = linked_model_path
+        gprops = tool.Georeference.get_georeference_props()
-        tool.Ifc.set(ifc)
+        with NamedTemporaryFile(suffix=".ifc.cache.json", mode="w", delete=True) as tmp:
-        subject.save_linked_models_to_ifc()
+            link = props.links.add()
-
+            link.filepath = tmp.name.replace(".ifc.cache.json", ".ifc")
-        # Information and references to stay intact.
+            transformation = np.eye(4)
-        assert len(documents := ifc.by_type("IfcDocumentInformation")) == 1
+            transformation[0][3] = 4
-        assert documents[0].id() == document_id
+            link.transformation = ",".join(map(str, transformation.reshape(-1)))
-        assert documents[0].Name == "BBIM_Linked_Models"
+            json.dump({"model_project_north": "0", "model_origin_si": "5,0,0"}, tmp)
-        assert len(references := ifc.by_type("IfcDocumentReference")) == 1
+            tmp.flush()
-        assert references[0].id() == reference_id
+            gprops.model_project_north = "0"
-        assert references[0].Location == linked_model_path
+            gprops.model_origin_si = "2,0,0"
-
+            m = np.eye(4)
-    def test_save_linked_models_to_ifc_references_to_remove(self):
+            m[0][3] = 7
-        ifc = ifcopenshell.file()
+            assert np.allclose(subject.calculate_link_matrix(link), m)
-        links = tool.Project.get_project_props().links
-        ifcopenshell.api.root.create_entity(ifc, "IfcProject")
-
-        document = ifcopenshell.api.document.add_information(ifc)
-        document.Name = "BBIM_Linked_Models"
-        document_id = document.id()
-        reference = ifcopenshell.api.document.add_reference(ifc, document)
-        linked_model_path = "test.ifc"
-        reference.Location = linked_model_path
-
-        tool.Ifc.set(ifc)
-        subject.save_linked_models_to_ifc()
-        links.clear()
-
-        # Remove reference for removed link.
-        assert len(documents := ifc.by_type("IfcDocumentInformation")) == 1
-        assert documents[0].id() == document_id
-        assert documents[0].Name == "BBIM_Linked_Models"
-        assert len(ifc.by_type("IfcDocumentReference")) == 0
 
 
 class TestLoadingIfcSqlite(NewFile):

src/ifcgeom/mapping/IfcSectionedSolidHorizontal.cpp

@@ -61,33 +61,9 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSectionedSolidHorizontal* in
 
 		longitudes.push_back(*pbde->DistanceAlong()->as<IfcSchema::IfcLengthMeasure>(true) * length_unit_);
 
-		// Corresponds to the profile X, Y directions (hopefully).
+		auto linear_placement = taxonomy::cast<taxonomy::matrix4>(map(csp));
-		Eigen::Vector3d po(
+      profile_offsets.push_back(linear_placement->ccomponents().block<3, 1>(0, 3));
-			pbde->OffsetLateral().get_value_or(0.),
+		boost::optional<Eigen::Matrix3d> rot(linear_placement->ccomponents().block<3,3>(0,0));
-			// @todo I don't understand whether vertical is an offset relative to the tangent plane or to the global XY plane
-			pbde->OffsetVertical().get_value_or(0.),
-			0.
-		);
-
-		profile_offsets.push_back(po);
-
-		boost::optional<Eigen::Matrix3d> rot;
-		if (csp->Axis() && csp->RefDirection()) {
-			rot = taxonomy::matrix4(
-				Eigen::Vector3d(0, 0, 0),
-				taxonomy::cast<taxonomy::direction3>(map(csp->Axis()))->ccomponents(),
-				taxonomy::cast<taxonomy::direction3>(map(csp->RefDirection()))->ccomponents()).ccomponents().block<3,3>(0,0);
-		} else if (csp->Axis()) {
-			rot = taxonomy::matrix4(
-				Eigen::Vector3d(0, 0, 0),
-				taxonomy::cast<taxonomy::direction3>(map(csp->Axis()))->ccomponents()).ccomponents().block<3, 3>(0, 0);
-        } else if (csp->RefDirection()) {
-            rot = taxonomy::matrix4(
-                Eigen::Vector3d(0, 0, 0),
-                Eigen::Vector3d(0, 0, 1),
-                taxonomy::cast<taxonomy::direction3>(map(csp->RefDirection()))->ccomponents()
-			).ccomponents().block<3, 3>(0, 0);
-        }
 		profile_rotations.push_back(rot);
 	}
 	if (faces.size() != profile_offsets.size()) {

src/ifcgeom/mapping/IfcSectionedSurface.cpp

@@ -63,35 +63,10 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSectionedSurface* inst) {
 
 		longitudes.push_back(*pbde->DistanceAlong()->as<IfcSchema::IfcLengthMeasure>(true) * length_unit_);
 
-		// Corresponds to the profile X, Y directions (hopefully).
+		auto linear_placement = taxonomy::cast<taxonomy::matrix4>(map(csp));
-		Eigen::Vector3d po(
+      profile_offsets.push_back(linear_placement->ccomponents().block<3, 1>(0, 3));
-			pbde->OffsetLateral().get_value_or(0.),
+      boost::optional<Eigen::Matrix3d> rot(linear_placement->ccomponents().block<3, 3>(0, 0));
-			// @todo I don't understand whether vertical is an offset relative to the tangent plane or to the global XY plane
+      profile_rotations.push_back(rot);
-			pbde->OffsetVertical().get_value_or(0.),
-			0.
-		);
-
-		profile_offsets.push_back(po);
-
-		boost::optional<Eigen::Matrix3d> rot;
-		if (csp->Axis() && csp->RefDirection()) {
-			rot = taxonomy::matrix4(
-				Eigen::Vector3d(0, 0, 0),
-				taxonomy::cast<taxonomy::direction3>(map(csp->Axis()))->ccomponents(),
-				taxonomy::cast<taxonomy::direction3>(map(csp->RefDirection()))->ccomponents()).ccomponents().block<3, 3>(0, 0);
-		} else if (csp->Axis()) {
-			rot = taxonomy::matrix4(
-				Eigen::Vector3d(0, 0, 0),
-				taxonomy::cast<taxonomy::direction3>(map(csp->Axis()))->ccomponents()).ccomponents().block<3, 3>(0, 0);
-        } else if (csp->RefDirection()) {
-            rot = taxonomy::matrix4(
-                      Eigen::Vector3d(0, 0, 0),
-                      Eigen::Vector3d(0, 0, 1),
-                      taxonomy::cast<taxonomy::direction3>(map(csp->RefDirection()))->ccomponents())
-                      .ccomponents()
-                      .block<3, 3>(0, 0);
-        }
-		profile_rotations.push_back(rot);
 	}
 #else
 	return nullptr;

src/ifcopenshell-python/ifcopenshell/util/geolocation.py

@@ -18,7 +18,7 @@
 
 import math
 from decimal import ROUND_HALF_UP, Decimal
-from typing import NamedTuple, Optional, Union
+from typing import NamedTuple, Optional, Union, Any
 
 import numpy as np
 
@@ -268,6 +268,15 @@ def get_helmert_transformation_parameters(ifc_file: ifcopenshell.file) -> Option
     return HelmertTransformation(e, n, h, xaa, xao, scale, factor_x, factor_y, factor_z)
 
 
+def get_crs(ifc_file: ifcopenshell.file) -> dict[str, Any]:
+    """Get CRS information from an IFC file."""
+    if ifc_file.schema == "IFC2X3":
+        return ifcopenshell.util.element.get_pset(ifc_file.by_type("IfcProject")[0], "ePSet_ProjectedCRS")
+    for context in ifc_file.by_type("IfcGeometricRepresentationContext", include_subtypes=False):
+        if operation := context.HasCoordinateOperation:
+            return operation[0].TargetCRS.get_info()
+
+
 def auto_z2e(ifc_file: ifcopenshell.file, z: float, should_return_in_map_units: bool = True) -> float:
     """Convert a Z coordinate to an elevation using model georeferencing data