Rework memory mngmt

as it is the main IFC4X3 schema

.github/workflows/ci-ifcsverchok-build.yml

@@ -0,0 +1,53 @@
+name: Publish-ifcsverchok
+
+on:
+  push:
+    paths:
+      - '.github/workflows/ci-ifcsverchok-build.yml'
+      - 'src/ifcsverchok/*'
+    branches:
+      - v0.7.0
+
+env:
+  major: 0
+  minor: 0
+  name: ifcsverchok
+
+jobs:
+  activate:
+    runs-on: ubuntu-latest
+    if: |
+      github.repository == 'IfcOpenShell/IfcOpenShell'
+    steps:
+    - name: Set env
+      run: echo ok go
+
+  build:
+    needs: activate
+    name: ifcsverchok
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2 # https://github.com/actions/setup-python
+        with:
+          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
+          python-version: '3.11'
+      - run: echo ${{ env.DATE }}
+      - name: Get current date
+        id: date
+        run: echo "::set-output name=date::$(date +'%y%m%d')"
+      - name: Compile
+        run: |
+          cd src/ifcsverchok
+          make dist
+      - name: Upload Zip file to release
+        uses: svenstaro/upload-release-action@v2
+        with:
+          repo_token: ${{ secrets.GITHUB_TOKEN }}
+          file: src/ifcsverchok/dist/ifcsverchok-${{steps.date.outputs.date}}.zip
+          asset_name: ifcsverchok-${{steps.date.outputs.date}}.zip
+          tag: "ifcsverchok-${{steps.date.outputs.date}}"
+          overwrite: true
+          body: "ifcsverchok build for ${{steps.date.outputs.date}}"

aws/lambda/Dockerfile

@@ -12,7 +12,7 @@ RUN apt-get -y update && apt-get -y install unzip curl
 # Install AWS Lambda runtime interface client
 RUN pip install --target ${FUNCTION_DIR} awslambdaric
 
-# Set the IfcOpenShell build version (check available builds at: https://blenderbim.org/docs-python/ifcopenshell-python/installation.html)
+# Set the IfcOpenShell build version (check available builds at: https://docs.ifcopenshell.org/ifcopenshell-python/installation.html)
 ARG IFC_OPENSHELL_BUILD="39-v0.7.0-476ab50"
 
 # Download and extract IfcOpenShell

choco/blenderbim/blenderbim.nuspec

@@ -15,7 +15,7 @@
     <licenseUrl>https://github.com/IfcOpenShell/IfcOpenShell/blob/v0.7.0/COPYING</licenseUrl>
     <requireLicenseAcceptance>true</requireLicenseAcceptance>
     <projectSourceUrl>https://github.com/IfcOpenShell/IfcOpenShell</projectSourceUrl>
-    <docsUrl>https://blenderbim.org/docs/</docsUrl>
+    <docsUrl>https://docs.blenderbim.org/</docsUrl>
     <!--<mailingListUrl></mailingListUrl>-->
     <bugTrackerUrl>https://github.com/IfcOpenShell/IfcOpenShell/issues</bugTrackerUrl>
     <tags>blender bim blenderbim ifc python opensource foss</tags>

cmake/CMakeLists.txt

@@ -746,7 +746,7 @@ if(NOT SCHEMA_VERSIONS)
         # super arbitrarily try to keep size down at least a little bit
         set(SCHEMA_VERSIONS "2x3" "4")
     else()
-        set(SCHEMA_VERSIONS "2x3" "4" "4x1" "4x2" "4x3_tc1" "4x3_add1" "4x3_add2")
+        set(SCHEMA_VERSIONS "2x3" "4" "4x1" "4x2" "4x3" "4x3_tc1" "4x3_add1" "4x3_add2")
     endif()
 endif()
 

nix/build-all.py

@@ -51,6 +51,7 @@
 ###############################################################################
 import logging
 import os
+import re
 import sys
 import subprocess as sp
 import shutil
@@ -468,6 +469,8 @@ if "wasm" in flags:
 # If the linker supports GC sections, set it up to reduce binary file size
 # -fPIC is required for the shared libraries to work
 
+compiler_flags = "CFLAGS", "CXXFLAGS", "LDFLAGS"
+
 CXXFLAGS = os.environ.get("CXXFLAGS", "")
 CFLAGS = os.environ.get("CFLAGS", "")
 LDFLAGS = os.environ.get("LDFLAGS", "")
@@ -493,7 +496,11 @@ else:
         CXXFLAGS=CXXFLAGS_MINIMAL
         CFLAGS=CFLAGS_MINIMAL
     LDFLAGS = f"{LDFLAGS} {ADDITIONAL_ARGS_STR}"
-    
+
+if "lto" in flags:
+    for f in compiler_flags:
+        locals()[f] += f" -flto={IFCOS_NUM_BUILD_PROCS}"
+
 os.environ["CXXFLAGS"] = CXXFLAGS
 os.environ["CFLAGS"] = CFLAGS
 os.environ["LDFLAGS"] = LDFLAGS
@@ -503,6 +510,11 @@ os.environ["LDFLAGS"] = LDFLAGS
 # build_dependency(name="cmake-%s" % (CMAKE_VERSION,), mode="autoconf", build_tool_args=[], download_url="https://cmake.org/files/v%s" % (CMAKE_VERSION_2,), download_name="cmake-%s.tar.gz" % (CMAKE_VERSION,))
 
 if 'hdf5' in targets:
+    # not supported
+    orig = [os.environ[f] for f in compiler_flags]
+    for f in compiler_flags:
+        os.environ[f] = re.sub("-flto(=\w+)?", "", os.environ[f])
+
     HDF5_MAJOR = ".".join(HDF5_VERSION.split(".")[:-1])
     build_dependency(
         name=f"hdf5-{HDF5_VERSION}",
@@ -513,6 +525,10 @@ if 'hdf5' in targets:
         ctest_result=f"HDF5-{HDF5_VERSION}-{platform.system()}",
         ctest_result_path=f"HDF_Group/HDF5/{HDF5_VERSION}"
     )
+    
+    for f, o in zip(compiler_flags, orig):
+        os.environ[f] = o
+    
 
 if "json" in targets:
     json_url = f"https://github.com/nlohmann/json/releases/download/{JSON_VERSION}/json.hpp"

src/blenderbim/blenderbim/bim/ifc.py

@@ -148,7 +148,7 @@ class IfcStore:
                 bpy.context.scene.BIMProjectProperties.export_schema
             )
         elif IfcStore.schema is None:
-            IfcStore.schema = ifcopenshell.ifcopenshell_wrapper.schema_by_name(IfcStore.file.schema)
+            IfcStore.schema = ifcopenshell.ifcopenshell_wrapper.schema_by_name(IfcStore.file.schema_identifier)
         return IfcStore.schema
 
     @staticmethod

src/blenderbim/blenderbim/bim/import_ifc.py

@@ -199,7 +199,7 @@ class MaterialCreator:
 
 
 class IfcImporter:
-    def __init__(self, ifc_import_settings):
+    def __init__(self, ifc_import_settings: IfcImportSettings):
         self.ifc_import_settings = ifc_import_settings
         self.diff = None
         self.file: ifcopenshell.file = None
@@ -391,20 +391,20 @@ class IfcImporter:
 
         for context in self.contexts:
             settings = ifcopenshell.geom.settings()
-            settings.set_deflection_tolerance(self.ifc_import_settings.deflection_tolerance)
-            settings.set_angular_tolerance(self.ifc_import_settings.angular_tolerance)
-            settings.set(settings.STRICT_TOLERANCE, True)
-            settings.set(settings.INCLUDE_CURVES, True)
-            settings.set_context_ids([context.id()])
+            settings.set('mesher-linear-deflection', self.ifc_import_settings.deflection_tolerance)
+            settings.set('mesher-angular-deflection', self.ifc_import_settings.angular_tolerance)
+            # settings.set(settings.STRICT_TOLERANCE, True)
+            settings.set('dimensionality', ifcopenshell.ifcopenshell_wrapper.CURVES_SURFACES_AND_SOLIDS)
+            settings.set('context-ids', [context.id()])
             self.context_settings.append(settings)
 
             settings = ifcopenshell.geom.settings()
-            settings.set_deflection_tolerance(self.ifc_import_settings.deflection_tolerance)
-            settings.set_angular_tolerance(self.ifc_import_settings.angular_tolerance)
-            settings.set(settings.STRICT_TOLERANCE, True)
-            settings.set(settings.INCLUDE_CURVES, True)
-            settings.set(settings.DISABLE_OPENING_SUBTRACTIONS, True)
-            settings.set_context_ids([context.id()])
+            settings.set('mesher-linear-deflection', self.ifc_import_settings.deflection_tolerance)
+            settings.set('mesher-angular-deflection', self.ifc_import_settings.angular_tolerance)
+            # settings.set(settings.STRICT_TOLERANCE, True)
+            settings.set('dimensionality', ifcopenshell.ifcopenshell_wrapper.CURVES_SURFACES_AND_SOLIDS)
+            settings.set('disable-opening-subtractions', True)
+            settings.set('context-ids', [context.id()])
             self.gross_context_settings.append(settings)
 
     def process_element_filter(self):
@@ -430,7 +430,7 @@ class IfcImporter:
         self.annotations = set([a for a in self.file.by_type("IfcAnnotation")])
         self.annotations -= drawing_annotations
 
-        self.elements = [e for e in self.elements if not e.is_a("IfcFeatureElement")]
+        self.elements = [e for e in self.elements if not e.is_a("IfcFeatureElement") or e.is_a("IfcSurfaceFeature")]
         if self.ifc_import_settings.is_coordinating:
             self.elements = [e for e in self.elements if e.Representation]
 
@@ -693,10 +693,7 @@ class IfcImporter:
             shape = self.create_generic_shape(element)
             if not shape:
                 continue
-            m = shape.transformation.matrix.data
-            mat = np.array(
-                ([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1])
-            )
+            mat = np.array(shape.transformation.matrix).reshape((4, 4), order="F")
             point = np.array(
                 (
                     shape.geometry.verts[0] / self.unit_scale,
@@ -725,7 +722,7 @@ class IfcImporter:
                         if len(subelement.Coordinates) == 3 and self.is_point_far_away(subelement, is_meters=False):
                             return True
 
-    def apply_blender_offset_to_matrix_world(self, obj, matrix):
+    def apply_blender_offset_to_matrix_world(self, obj: bpy.types.Object, matrix: np.ndarray) -> mathutils.Matrix:
         props = bpy.context.scene.BIMGeoreferenceProperties
         if props.has_blender_offset:
             if obj.data and obj.data.get("has_cartesian_point_offset", None):
@@ -857,7 +854,10 @@ class IfcImporter:
         print("Done creating geometry")
 
     def create_spatial_elements(self) -> None:
-        self.create_generic_elements(self.spatial_elements, unselectable=True)
+        if bpy.context.preferences.addons["blenderbim"].preferences.spatial_elements_unselectable:
+            self.create_generic_elements(self.spatial_elements, unselectable=True)
+        else:
+            self.create_generic_elements(self.spatial_elements, unselectable=False)
 
     def create_elements(self) -> None:
         self.create_generic_elements(self.elements)
@@ -949,7 +949,9 @@ class IfcImporter:
             self.create_product(element, mesh=mesh)
 
     def create_products(
-        self, products, settings: Optional[ifcopenshell.geom.main.settings] = None
+        self,
+        products: set[ifcopenshell.entity_instance],
+        settings: Optional[ifcopenshell.geom.main.settings] = None,
     ) -> set[ifcopenshell.entity_instance]:
         results = set()
         if not products:
@@ -1149,11 +1151,8 @@ class IfcImporter:
         self.link_element(element, obj)
 
         if shape:
-            m = shape.transformation.matrix.data
             # We use numpy here because Blender mathutils.Matrix is not accurate enough
-            mat = np.array(
-                ([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1])
-            )
+            mat = np.array(shape.transformation.matrix).reshape((4, 4), order="F")
             self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, mat))
             self.material_creator.create(element, obj, mesh)
         elif mesh:
@@ -1623,30 +1622,34 @@ class IfcImporter:
         if self.ifc_import_settings.has_filter:
             rel_aggregates = set()
             for element in self.elements:
-                if element.IsDecomposedBy:
-                    rel_aggregates.add(element.IsDecomposedBy[0])
-                elif element.Decomposes:
-                    rel_aggregates.add(element.Decomposes[0])
-                elif getattr(element, "IsNestedBy", []):  # IFC2X3 does not have IsNestedBy
-                    if [e for e in element.IsNestedBy[0].RelatedObjects if not e.is_a("IfcPort")]:
-                        rel_aggregates.add(element.IsNestedBy[0])
-                elif getattr(element, "Nests", []):
-                    rel_aggregates.add(element.Nests[0])
+                if decomposed_by := element.IsDecomposedBy:
+                    rel_aggregates.add(decomposed_by[0])
+                elif decomposes := element.Decomposes:
+                    rel_aggregates.add(decomposes[0])
+                elif nested_by := getattr(element, "IsNestedBy", []):  # IFC2X3 does not have IsNestedBy
+                    if next((e for e in nested_by[0].RelatedObjects if not e.is_a("IfcPort")), None):
+                        rel_aggregates.add(nested_by[0])
+                elif nests := getattr(element, "Nests", []):
+                    rel_aggregates.add(nests[0])
+                elif element.is_a("IfcSurfaceFeature") and self.file.schema == "IFC4X3":
+                    rel_aggregates.add(element.AdheresToElement[0])
         else:
             rel_aggregates = [
                 r
                 for r in self.file.by_type("IfcRelAggregates")
-                if r.RelatingObject.is_a("IfcElement") or r.RelatingObject.is_a("IfcElementType")
+                if (relating_obj := r.RelatingObject).is_a("IfcElement") or relating_obj.is_a("IfcElementType")
             ] + [
                 r
                 for r in self.file.by_type("IfcRelNests")
                 if (
-                    r.RelatingObject.is_a("IfcElement")
-                    or r.RelatingObject.is_a("IfcElementType")
-                    or (r.RelatingObject.is_a("IfcPositioningElement") and not r.RelatingObject.is_a("IfcGrid"))
+                    (relating_obj := r.RelatingObject).is_a("IfcElement")
+                    or relating_obj.is_a("IfcElementType")
+                    or (relating_obj.is_a("IfcPositioningElement") and not relating_obj.is_a("IfcGrid"))
                 )
                 and [e for e in r.RelatedObjects if not e.is_a("IfcPort")]
             ]
+            if self.file.schema == "IFC4X3":
+                rel_aggregates += [r for r in self.file.by_type("IfcRelAdheresToElement")]
 
         if len(rel_aggregates) > 10000:
             # More than 10,000 collections makes Blender unhappy
@@ -1656,7 +1659,9 @@ class IfcImporter:
 
         aggregates: dict[str, dict] = {}
         for rel_aggregate in rel_aggregates:
-            element: ifcopenshell.entity_instance = rel_aggregate.RelatingObject
+            element: ifcopenshell.entity_instance = getattr(rel_aggregate, "RelatingObject", None) or getattr(
+                rel_aggregate, "RelatingElement"
+            )
             collection = bpy.data.collections.new(tool.Loader.get_name(element))
             aggregates[element.GlobalId] = {"element": element, "collection": collection}
             self.collections[element.GlobalId] = collection
@@ -1757,6 +1762,9 @@ class IfcImporter:
         elif getattr(element, "Nests", None) and not element.is_a("IfcPort"):
             nest = ifcopenshell.util.element.get_nest(element)
             return self.collections[nest.GlobalId].objects.link(obj)
+        elif element.is_a("IfcSurfaceFeature") and self.file.schema == "IFC4X3":
+            adherend = element.AdheresToElement[0].RelatingElement
+            return self.collections[adherend.GlobalId].objects.link(obj)
 
         return self.place_object_in_spatial_decomposition_collection(element, obj)
 
@@ -1806,7 +1814,7 @@ class IfcImporter:
             if rel.is_a("IfcRelAssignsToGroup") and rel.RelatingGroup.ObjectType == "DRAWING":
                 return rel.RelatingGroup
 
-    def get_element_matrix(self, element: ifcopenshell.entity_instance) -> np.array:
+    def get_element_matrix(self, element: ifcopenshell.entity_instance) -> np.ndarray:
         if isinstance(element, ifcopenshell.sqlite_entity):
             result = self.geometry_cache["shapes"][element.id()]["matrix"]
         else:
@@ -1889,10 +1897,7 @@ class IfcImporter:
                 and geometry.verts
                 and self.is_point_far_away((geometry.verts[0], geometry.verts[1], geometry.verts[2]))
             ):
-                m = shape.transformation.matrix.data
-                mat = np.array(
-                    ([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1])
-                )
+                mat = np.array(shape.transformation.matrix).reshape((4, 4), order="F")
                 offset_point = np.linalg.inv(mat) @ np.array(
                     (
                         float(props.blender_eastings),
@@ -1946,7 +1951,7 @@ class IfcImporter:
                 edges = [[e[i], e[i + 1]] for i in range(0, len(e), 2)]
                 mesh.from_pydata(vertices, edges, [])
 
-            mesh["ios_materials"] = [int(m.name.split("-")[2]) for m in geometry.materials]
+            mesh["ios_materials"] = [m.instance_id() for m in geometry.materials]
             mesh["ios_material_ids"] = geometry.material_ids
             return mesh
         except:
@@ -1955,14 +1960,14 @@ class IfcImporter:
 
             print(traceback.format_exc())
 
-    def a2p(self, o, z, x):
+    def a2p(self, o: mathutils.Vector, z: mathutils.Vector, x: mathutils.Vector) -> mathutils.Matrix:
         y = z.cross(x)
         r = mathutils.Matrix((x, y, z, o))
         r.resize_4x4()
         r.transpose()
         return r
 
-    def get_axis2placement(self, plc):
+    def get_axis2placement(self, plc: ifcopenshell.entity_instance) -> mathutils.Matrix:
         if plc.is_a("IfcAxis2Placement3D"):
             z = mathutils.Vector(plc.Axis.DirectionRatios if plc.Axis else (0, 0, 1))
             x = mathutils.Vector(plc.RefDirection.DirectionRatios if plc.RefDirection else (1, 0, 0))
@@ -1982,7 +1987,7 @@ class IfcImporter:
         o = plc.LocalOrigin.Coordinates
         return self.a2p(o, z, x)
 
-    def get_local_placement(self, plc):
+    def get_local_placement(self, plc: Optional[ifcopenshell.entity_instance] = None) -> mathutils.Matrix:
         if plc is None:
             return mathutils.Matrix()
         if plc.PlacementRelTo is None:
@@ -1997,11 +2002,11 @@ class IfcImporter:
                 bpy.context.scene.BIMRootProperties.contexts = str(subcontext.id())
                 break
 
-    def link_element(self, element, obj):
+    def link_element(self, element: ifcopenshell.entity_instance, obj: IFC_CONNECTED_TYPE) -> None:
         self.added_data[element.id()] = obj
         tool.Ifc.link(element, obj)
 
-    def set_matrix_world(self, obj, matrix_world):
+    def set_matrix_world(self, obj: bpy.types.Object, matrix_world: mathutils.Matrix) -> None:
         obj.matrix_world = matrix_world
         tool.Geometry.record_object_position(obj)
 

src/blenderbim/blenderbim/bim/module/aggregate/operator.py

@@ -190,12 +190,17 @@ class BIM_OT_select_parts(bpy.types.Operator):
 
     def execute(self, context):
         self.file = IfcStore.get_file()
-        obj = bpy.data.objects.get(self.obj) or context.active_object
-        parts = ifcopenshell.util.element.get_parts(tool.Ifc.get_entity(obj))
-        parts_objs = set(tool.Ifc.get_object(part) for part in parts)
-        selectable_parts_objs = set(context.selectable_objects).intersection(parts_objs)
-        for selectable_part_obj in selectable_parts_objs:
-            selectable_part_obj.select_set(True)
+        # obj = bpy.data.objects.get(self.obj) or context.active_object
+
+        for obj in context.selected_objects:
+            parts = ifcopenshell.util.element.get_parts(tool.Ifc.get_entity(obj))
+            if parts:
+                parts_objs = set(tool.Ifc.get_object(part) for part in parts)
+                selectable_parts_objs = set(context.selectable_objects).intersection(parts_objs)
+                for selectable_part_obj in selectable_parts_objs:
+                    selectable_part_obj.select_set(True)
+            else:
+                obj.select_set(False)
         return {"FINISHED"}
 
 
@@ -217,18 +222,43 @@ class BIM_OT_select_aggregate(bpy.types.Operator):
 
     def execute(self, context):
         self.file = IfcStore.get_file()
-        obj = bpy.data.objects.get(self.obj) or context.active_object
-        aggregate = ifcopenshell.util.element.get_aggregate(tool.Ifc.get_entity(obj))
-        aggregate_obj = tool.Ifc.get_object(aggregate)
+
+        # obj = bpy.data.objects.get(self.obj) or context.active_object
+        # aggregate = ifcopenshell.util.element.get_aggregate(tool.Ifc.get_entity(obj))
+        # aggregate_obj = tool.Ifc.get_object(aggregate)
+        
+        all_parts = []
+        for obj in context.selected_objects:
+            element = tool.Ifc.get_entity(obj)
+            if element:
+                aggregate = ifcopenshell.util.element.get_aggregate(element)
+                if aggregate:
+                    all_parts.append(aggregate)
+                    obj.select_set(False)
+                else:
+                    pass
+            if not element:
+                obj.select_set(False)
+        
         if self.select_parts:
-            bpy.ops.bim.select_parts(obj=aggregate_obj.name)
-        if aggregate_obj in context.selectable_objects:
-            tool.Blender.set_objects_selection(
-                context,
-                aggregate_obj,
-                [aggregate_obj],
-                clear_previous_selection=not self.select_parts,
-            )
+            all_objs = []
+            for part in all_parts:
+                if part.IsDecomposedBy:
+                    for subpart in part.IsDecomposedBy[0].RelatedObjects:
+                        all_parts.append(subpart)
+                all_objs.append(part)
+
+            for element in all_objs:
+                obj = tool.Ifc.get_object(element)
+                if obj:
+                    obj.select_set(True)
+
+        else:
+            for aggregate_element in all_parts:
+                aggregate_obj = tool.Ifc.get_object(aggregate_element)
+                aggregate_obj.select_set(True)
+                bpy.context.view_layer.objects.active = aggregate_obj      
+
         return {"FINISHED"}
 
 
@@ -292,28 +322,51 @@ class BIM_OT_select_linked_aggregates(bpy.types.Operator, Operator):
     bl_idname = "bim.select_linked_aggregates"
     bl_label = "Select linked aggregates"
     bl_options = {"REGISTER", "UNDO"}
+    select_parts: bpy.props.BoolProperty(default=False)
+
+    @classmethod
+    def description(cls, context, properties):
+        if properties.select_parts:
+            return "Select all aggregates, subaggregates and all their parts"
+        else:
+            return "Select all aggregates"
 
     def _execute(self, context):
-        element = tool.Ifc.get_entity(bpy.context.active_object)
-        aggregate = ifcopenshell.util.element.get_aggregate(element)
-        if not aggregate:
-            return []
-        if not element:
-            return []
-
-        linked_aggregate_group = [
-            r.RelatingGroup
-            for r in getattr(aggregate, "HasAssignments", []) or []
-            if r.is_a("IfcRelAssignsToGroup")
-            if "BBIM_Linked_Aggregate" in r.RelatingGroup.Name
-        ]
-
+        
         for obj in context.selected_objects:
             obj.select_set(False)
+            element = tool.Ifc.get_entity(obj)
+            aggregate = ifcopenshell.util.element.get_aggregate(element)
+            if not aggregate:
+                continue
+            if not element:
+                continue
 
-        for rel in linked_aggregate_group[0].IsGroupedBy or []:
-            for element in rel.RelatedObjects:
-                obj = tool.Ifc.get_object(element)
-                obj.select_set(True)
+            linked_aggregate_group = [
+                r.RelatingGroup
+                for r in getattr(aggregate, "HasAssignments", []) or []
+                if r.is_a("IfcRelAssignsToGroup")
+                if "BBIM_Linked_Aggregate" in r.RelatingGroup.Name
+            ]
+
+            group_rel = linked_aggregate_group[0].IsGroupedBy or []
+            for group_link in group_rel:
+                parts = list(group_link.RelatedObjects)
+                if self.select_parts:
+                    parts_objs = []
+                    for part in parts:
+                        if part.IsDecomposedBy:
+                            for subpart in part.IsDecomposedBy[0].RelatedObjects:
+                                parts.append(subpart)
+                        parts_objs.append(part)
+
+                    for element in parts_objs:
+                        obj = tool.Ifc.get_object(element)
+                        if obj:
+                            obj.select_set(True)
+                else:
+                    for element in parts:
+                        obj = tool.Ifc.get_object(element)
+                        obj.select_set(True)
 
         return {"FINISHED"}

src/blenderbim/blenderbim/bim/module/aggregate/ui.py

@@ -139,7 +139,10 @@ class BIM_PT_linked_aggregate(Panel):
         if type(AggregateData.data['total_linked_aggregate']) is int:
             if AggregateData.data['total_linked_aggregate'] > 0:
                 row.label(text=f"{AggregateData.data['total_linked_aggregate']} Linked Aggregates")
-                row.operator("bim.select_linked_aggregates", text="", icon="RESTRICT_SELECT_OFF")
+                op = row.operator("bim.select_linked_aggregates", text="", icon="OUTLINER_DATA_POINTCLOUD")
+                op.select_parts = False
+                op = row.operator("bim.select_linked_aggregates", text="", icon="OUTLINER_OB_POINTCLOUD")
+                op.select_parts = True
                 row.operator("bim.refresh_linked_aggregate", text="", icon="FILE_REFRESH")
                 op = row.operator("bim.break_link_to_other_aggregates", text="", icon="X")
         else:

src/blenderbim/blenderbim/bim/module/attribute/operator.py

@@ -47,10 +47,18 @@ class EnableEditingAttributes(bpy.types.Operator):
             obj = bpy.data.objects.get(self.obj)
         elif self.obj_type == "Material":
             obj = bpy.data.materials.get(self.obj)
-        oprops = obj.BIMObjectProperties
         props = obj.BIMAttributeProperties
         props.attributes.clear()
 
+        element = tool.Ifc.get_entity(obj)
+        has_inherited_predefined_type = False
+        if not element.is_a("IfcTypeObject") and (element_type := ifcopenshell.util.element.get_type(element)):
+            # Allow for None due to https://github.com/buildingSMART/IFC4.3.x-development/issues/818
+            has_inherited_predefined_type = ifcopenshell.util.element.get_predefined_type(element_type) not in (
+                "NOTDEFINED",
+                None,
+            )
+
         def callback(name, prop, data):
             if name in ("RefLatitude", "RefLongitude"):
                 new = props.attributes.add()
@@ -62,10 +70,11 @@ class EnableEditingAttributes(bpy.types.Operator):
                 new.string_value = "" if new.is_null else json.dumps(data[name])
                 blenderbim.bim.helper.add_attribute_description(new)
                 new.description += " The degrees, minutes and seconds should follow this format : [12,34,56]"
+            if name in ("PredefinedType", "ObjectType") and has_inherited_predefined_type:
+                props.attributes.remove(len(props.attributes) - 1)
+                return True
 
-        blenderbim.bim.helper.import_attributes2(
-            tool.Ifc.get().by_id(oprops.ifc_definition_id), props.attributes, callback=callback
-        )
+        blenderbim.bim.helper.import_attributes2(element, props.attributes, callback=callback)
         props.is_editing_attributes = True
         return {"FINISHED"}
 

src/blenderbim/blenderbim/bim/module/boundary/operator.py

@@ -832,7 +832,7 @@ class AddBoundary(bpy.types.Operator, tool.Ifc.Operator):
                         settings = ifcopenshell.geom.settings()
                         settings.set(settings.STRICT_TOLERANCE, True)
                         shape = ifcopenshell.geom.create_shape(settings, opening)
-                        m = shape.transformation.matrix.data
+                        m = shape.transformation.matrix
                         mat = Matrix(
                             (
                                 [m[0], m[3], m[6], m[9]],
@@ -1035,7 +1035,7 @@ class AddBoundary(bpy.types.Operator, tool.Ifc.Operator):
         settings.set(settings.STRICT_TOLERANCE, True)
         # geometry = ifcopenshell.geom.create_shape(settings, body)
         shape = ifcopenshell.geom.create_shape(settings, element)
-        m = shape.transformation.matrix.data
+        m = shape.transformation.matrix
         mat = Matrix(([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1]))
         verts = [space_matrix_i @ mat @ Vector(v) for v in ifcopenshell.util.shape.get_vertices(shape.geometry)]
         faces = ifcopenshell.util.shape.get_faces(shape.geometry)

src/blenderbim/blenderbim/bim/module/classification/operator.py

@@ -20,6 +20,8 @@ import bpy
 import json
 import ifcopenshell
 import ifcopenshell.api
+import ifcopenshell.util.classification
+import ifcopenshell.util.element
 import blenderbim.tool as tool
 import blenderbim.bim.helper
 from blenderbim.bim.ifc import IfcStore
@@ -87,7 +89,7 @@ class AddManualClassificationReference(bpy.types.Operator, tool.Ifc.Operator):
         reference = ifcopenshell.api.run(
             "classification.add_reference",
             tool.Ifc.get(),
-            product=product,
+            products=[product],
             classification=classification,
             identification="X",
             name="Unnamed",
@@ -292,6 +294,7 @@ class RemoveClassificationReference(bpy.types.Operator, tool.Ifc.Operator):
         active_reference = tool.Ifc.get().by_id(self.reference)
         identification = active_reference[1]
 
+        elements_by_references: dict[ifcopenshell.entity_instance, list[ifcopenshell.entity_instance]] = {}
         for obj in objects:
             ifc_definition_id = tool.Blender.get_obj_ifc_definition_id(obj, self.obj_type, context)
             element = tool.Ifc.get().by_id(ifc_definition_id)
@@ -300,12 +303,16 @@ class RemoveClassificationReference(bpy.types.Operator, tool.Ifc.Operator):
                 if (identification and reference[1] == identification) or (
                     not identification and reference == active_reference
                 ):
-                    ifcopenshell.api.run(
-                        "classification.remove_reference",
-                        tool.Ifc.get(),
-                        reference=reference,
-                        product=element,
-                    )
+                    elements_by_references.setdefault(reference, []).append(element)
+
+        if elements_by_references:
+            for reference, products in elements_by_references.items():
+                ifcopenshell.api.run(
+                    "classification.remove_reference",
+                    tool.Ifc.get(),
+                    reference=reference,
+                    products=products,
+                )
 
 
 class EditClassificationReference(bpy.types.Operator, tool.Ifc.Operator):
@@ -357,15 +364,18 @@ class AddClassificationReference(bpy.types.Operator, tool.Ifc.Operator):
                 classification = element
                 break
 
-        for obj in objects:
-            ifc_definition_id = tool.Blender.get_obj_ifc_definition_id(obj, self.obj_type, context)
-            if not ifc_definition_id:
-                continue
+        ifc_file = tool.Ifc.get()
+        products = [
+            ifc_file.by_id(ifc_definition_id)
+            for obj in objects
+            if (ifc_definition_id := tool.Blender.get_obj_ifc_definition_id(obj, self.obj_type, context))
+        ]
+        if products:
             ifcopenshell.api.run(
                 "classification.add_reference",
                 tool.Ifc.get(),
                 reference=IfcStore.classification_file.by_id(self.reference),
-                product=tool.Ifc.get().by_id(ifc_definition_id),
+                products=products,
                 classification=classification,
             )
 
@@ -413,7 +423,7 @@ class AddClassificationReferenceFromBSDD(bpy.types.Operator, tool.Ifc.Operator):
             reference = ifcopenshell.api.run(
                 "classification.add_reference",
                 tool.Ifc.get(),
-                product=element,
+                products=[element],
                 classification=classification,
                 identification=bsdd_classification.reference_code,
                 name=bsdd_classification.name,

src/blenderbim/blenderbim/bim/module/constraint/operator.py

@@ -114,7 +114,7 @@ class EditObjective(bpy.types.Operator):
         ifcopenshell.api.run(
             "constraint.edit_objective",
             self.file,
-            **{"objective": self.file.by_id(props.active_constraint_id), "attributes": attributes}
+            **{"objective": self.file.by_id(props.active_constraint_id), "attributes": attributes},
         )
         bpy.ops.bim.load_objectives()
         return {"FINISHED"}
@@ -179,19 +179,17 @@ class AssignConstraint(bpy.types.Operator):
         return IfcStore.execute_ifc_operator(self, context)
 
     def _execute(self, context):
-        self.file = IfcStore.get_file()
+        self.file = tool.Ifc.get()
         objs = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
-        for obj in objs:
-            obj_id = obj.BIMObjectProperties.ifc_definition_id
-            if not obj_id:
-                continue
+        products = [self.file.by_id(obj_id) for obj in objs if (obj_id := obj.BIMObjectProperties.ifc_definition_id)]
+        if products:
             ifcopenshell.api.run(
                 "constraint.assign_constraint",
                 self.file,
                 **{
-                    "product": self.file.by_id(obj_id),
+                    "products": products,
                     "constraint": self.file.by_id(self.constraint),
-                }
+                },
             )
         return {"FINISHED"}
 
@@ -207,18 +205,16 @@ class UnassignConstraint(bpy.types.Operator):
         return IfcStore.execute_ifc_operator(self, context)
 
     def _execute(self, context):
-        self.file = IfcStore.get_file()
+        self.file = tool.Ifc.get()
         objs = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
-        for obj in objs:
-            obj_id = obj.BIMObjectProperties.ifc_definition_id
-            if not obj_id:
-                continue
+        products = [self.file.by_id(obj_id) for obj in objs if (obj_id := obj.BIMObjectProperties.ifc_definition_id)]
+        if products:
             ifcopenshell.api.run(
                 "constraint.unassign_constraint",
                 self.file,
                 **{
-                    "product": self.file.by_id(obj_id),
+                    "products": products,
                     "constraint": self.file.by_id(self.constraint),
-                }
+                },
             )
         return {"FINISHED"}

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

@@ -2373,6 +2373,7 @@ class LoadSheets(bpy.types.Operator, Operator):
             if not filepath.is_file():
                 sheet_name = f"{sheet_prop.identification} - {sheet_prop.name}"
                 sheets_not_found.append(f'"{sheet_name}" - {document_uri}')
+                core.regenerate_sheet(tool.Drawing, sheet)
 
         if sheets_not_found:
             self.report({"ERROR"}, "Some sheets svg files are missing:\n" + "\n".join(sheets_not_found))
@@ -2570,8 +2571,16 @@ class EnableEditingElementFilter(bpy.types.Operator, Operator):
 
     def _execute(self, context):
         obj = bpy.context.scene.camera
-        if obj:
-            obj.data.BIMCameraProperties.filter_mode = self.filter_mode
+        if not obj:
+            return
+        obj.data.BIMCameraProperties.filter_mode = self.filter_mode
+        element = tool.Ifc.get_entity(obj)
+        if query := ifcopenshell.util.element.get_pset(element, "EPset_Drawing", self.filter_mode.title()):
+            filter_groups = tool.Search.get_filter_groups(f"drawing_{self.filter_mode.lower()}")
+            try:
+                tool.Search.import_filter_query(query, filter_groups)
+            except:
+                pass
 
 
 class EditElementFilter(bpy.types.Operator, Operator):

src/blenderbim/blenderbim/bim/module/drawing/prop.py

@@ -66,6 +66,11 @@ def get_location_hint(self, context):
 
 
 def update_diagram_scale(self, context):
+    if not context.scene.camera or context.scene.camera.data != self.id_data:
+        return
+    element = tool.Ifc.get_entity(context.scene.camera)
+    if not element:
+        return
     try:
         element = (
             tool.Ifc.get()
@@ -87,6 +92,11 @@ def update_diagram_scale(self, context):
 
 
 def update_is_nts(self, context):
+    if not context.scene.camera or context.scene.camera.data != self.id_data:
+        return
+    element = tool.Ifc.get_entity(context.scene.camera)
+    if not element:
+        return
     try:
         element = (
             tool.Ifc.get()

src/blenderbim/blenderbim/bim/module/drawing/svgwriter.py

@@ -93,7 +93,7 @@ class SvgWriter:
 
     def setup_drawing_resource_paths(self, element):
         pset = ifcopenshell.util.element.get_pset(element, "EPset_Drawing")
-        for resource in ("Stylesheet", "Markers", "Symbols", "Patterns"):
+        for resource in ("Stylesheet", "Markers", "Symbols", "Patterns", "ShadingStyles"):
             resource_path = pset.get(resource)
             if not resource_path:
                 self.resource_paths[resource] = None

src/blenderbim/blenderbim/bim/module/material/ui.py

@@ -175,7 +175,7 @@ class BIM_PT_object_material(Panel):
 
         if ObjectMaterialData.data["type_material"]:
             row = self.layout.row(align=True)
-            row.label(text="Inherited Material: " + ObjectMaterialData.data["type_material"], icon="FILE_PARENT")
+            row.label(text="Inherited Material: " + ObjectMaterialData.data["type_material"], icon="CON_CHILDOF")
 
         if ObjectMaterialData.data["material_class"]:
             return self.draw_material_ui()

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

@@ -25,6 +25,8 @@ classes = (
     operator.AppendLibraryElement,
     operator.AppendLibraryElementByQuery,
     operator.AssignLibraryDeclaration,
+    operator.BIM_OT_load_clipping_planes,
+    operator.BIM_OT_save_clipping_planes,
     operator.ChangeLibraryElement,
     operator.CreateClippingPlane,
     operator.CreateProject,

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

@@ -39,6 +39,8 @@ from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.ui import IFCFileSelector
 from blenderbim.bim import import_ifc
 from blenderbim.bim import export_ifc
+from collections import defaultdict
+import json
 from math import radians
 from pathlib import Path
 from mathutils import Vector, Matrix
@@ -734,7 +736,7 @@ class LoadProjectElements(bpy.types.Operator):
     def execute(self, context):
         self.props = context.scene.BIMProjectProperties
         self.file = IfcStore.get_file()
-        blenderbim.bim.schema.reload(self.file.schema)
+        blenderbim.bim.schema.reload(self.file.schema_identifier)
         start = time.time()
         logger = logging.getLogger("ImportIFC")
         path_log = os.path.join(context.scene.BIMProperties.data_dir, "process.log")
@@ -1425,7 +1427,7 @@ class LoadLinkedProject(bpy.types.Operator):
         return {"FINISHED"}
 
     def is_local(self, shape):
-        m = shape.transformation.matrix.data
+        m = shape.transformation.matrix
         if max([abs(co) for co in (m[9], m[10], m[11])]) > 1000:
             return False
         elif max([abs(co) for co in shape.geometry.verts[0:3]]) > 1000:
@@ -1434,13 +1436,13 @@ class LoadLinkedProject(bpy.types.Operator):
 
     def process_occurrence(self, shape):
         element = self.file.by_id(shape.id)
-        matrix = shape.transformation.matrix.data
+        matrix = shape.transformation.matrix
         faces = shape.geometry.faces
         verts = shape.geometry.verts
         materials = shape.geometry.materials
         material_ids = shape.geometry.material_ids
 
-        m = shape.transformation.matrix.data
+        m = shape.transformation.matrix
         mat = np.array(([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1]))
 
         mesh = self.meshes.get(shape.geometry.id, None)
@@ -1999,3 +2001,61 @@ class FlipClippingPlane(bpy.types.Operator):
             obj.rotation_euler[0] += radians(180)
             context.view_layer.update()
         return {"FINISHED"}
+
+
+CLIPPING_PLANES_FILE_NAME = "ClippingPlanes.json"  # TODO un-hardcode :=
+
+
+class BIM_OT_save_clipping_planes(bpy.types.Operator):
+    bl_idname = "bim.save_clipping_planes"
+    bl_label = "Save Clipping Planes"
+    bl_description = "Save Clipping Planes to Disk"
+    bl_options = {"REGISTER", "UNDO"}
+
+    @classmethod
+    def poll(cls, context):
+        if IfcStore.path:
+            return context.scene.BIMProjectProperties.clipping_planes
+        cls.poll_message_set("Please Save The IFC File")
+
+    def execute(self, context):
+        clipping_planes_to_serialize = defaultdict(dict)
+        clipping_planes = context.scene.BIMProjectProperties.clipping_planes
+        for clipping_plane in clipping_planes:
+            obj = clipping_plane.obj
+            name = obj.name
+            clipping_planes_to_serialize[name]["location"] = obj.location[0:3]
+            clipping_planes_to_serialize[name]["rotation"] = obj.rotation_euler[0:3]
+        with open(Path(IfcStore.path).with_name(CLIPPING_PLANES_FILE_NAME), "w") as file:
+            json.dump(clipping_planes_to_serialize, file, indent=4)
+        return {"FINISHED"}
+
+
+class BIM_OT_load_clipping_planes(bpy.types.Operator):
+    bl_idname = "bim.load_clipping_planes"
+    bl_label = "Load Clipping Planes"
+    bl_description = "Load Clipping Planes from Disk"
+    bl_options = {"REGISTER", "UNDO"}
+
+    @classmethod
+    def poll(cls, context):
+        if filepath := IfcStore.path:
+            if Path(filepath).with_name(CLIPPING_PLANES_FILE_NAME).exists():
+                return True
+            else:
+                cls.poll_message_set(f"No Clipping Planes File in Folder {filepath}")
+        else:
+            cls.poll_message_set("Please Save The IFC File")
+
+    def execute(self, context):
+        bpy.data.batch_remove(context.scene.BIMProjectProperties.clipping_planes_objs)
+        context.scene.BIMProjectProperties.clipping_planes.clear()
+        with open(Path(IfcStore.path).with_name(CLIPPING_PLANES_FILE_NAME), "r") as file:
+            clipping_planes_dict = json.load(file)
+        for name, values in clipping_planes_dict.items():
+            bpy.ops.bim.create_clipping_plane()
+            obj = context.scene.BIMProjectProperties.clipping_planes_objs[-1]
+            obj.name = name
+            obj.location = values["location"]
+            obj.rotation_euler = values["rotation"]
+        return {"FINISHED"}

src/blenderbim/blenderbim/bim/module/pset/data.py

@@ -69,6 +69,7 @@ class ObjectPsetsData(Data):
     @classmethod
     def load(cls):
         cls.data = {
+            "is_occurrence": cls.is_occurrence(),
             "psets": cls.psetqtos(tool.Ifc.get_entity(bpy.context.active_object), psets_only=True),
             "inherited_psets": cls.inherited_psets(),
             "pset_name": cls.pset_name(),
@@ -76,6 +77,10 @@ class ObjectPsetsData(Data):
         }
         cls.is_loaded = True
 
+    @classmethod
+    def is_occurrence(cls):
+        return not tool.Ifc.get_entity(bpy.context.active_object).is_a("IfcTypeObject")
+
     @classmethod
     def inherited_psets(cls):
         element = tool.Ifc.get_entity(bpy.context.active_object)
@@ -126,11 +131,16 @@ class ObjectQtosData(Data):
     @classmethod
     def load(cls):
         cls.data = {
+            "is_occurrence": cls.is_occurrence(),
             "qtos": cls.psetqtos(tool.Ifc.get_entity(bpy.context.active_object), qtos_only=True),
             "inherited_qsets": cls.inherited_qsets(),
         }
         cls.is_loaded = True
 
+    @classmethod
+    def is_occurrence(cls):
+        return not tool.Ifc.get_entity(bpy.context.active_object).is_a("IfcTypeObject")
+
     @classmethod
     def inherited_qsets(cls):
         element = tool.Ifc.get_entity(bpy.context.active_object)

src/blenderbim/blenderbim/bim/module/pset/ui.py

@@ -208,12 +208,15 @@ class BIM_PT_object_psets(Panel):
             draw_psetqto_ui(context, 0, {}, props, self.layout, "Object")
 
         if ObjectPsetsData.data["psets"]:
-            self.layout.label(text="Instance:")
+            if ObjectPsetsData.data["is_occurrence"]:
+                self.layout.label(text="Occurrence Properties:")
+            else:
+                self.layout.label(text="Type Properties:")
             for pset in ObjectPsetsData.data["psets"]:
                 draw_psetqto_ui(context, pset["id"], pset, props, self.layout, "Object")
 
         if ObjectPsetsData.data["inherited_psets"]:
-            self.layout.label(text="Type:")
+            self.layout.label(text="Inherited Type Properties:", icon="CON_CHILDOF")
             for pset in ObjectPsetsData.data["inherited_psets"]:
                 draw_psetqto_ui(context, pset["id"], pset, props, self.layout, "Object", allow_removing=False)
 
@@ -252,12 +255,15 @@ class BIM_PT_object_qtos(Panel):
             draw_psetqto_ui(context, 0, {}, props, self.layout, "Object")
 
         if ObjectQtosData.data["qtos"]:
-            self.layout.label(text="Instance:")
+            if ObjectQtosData.data["is_occurrence"]:
+                self.layout.label(text="Occurrence Quantities:")
+            else:
+                self.layout.label(text="Type Quantities:")
             for qto in ObjectQtosData.data["qtos"]:
                 draw_psetqto_ui(context, qto["id"], qto, props, self.layout, "Object")
 
         if ObjectQtosData.data["inherited_qsets"]:
-            self.layout.label(text="Type:")
+            self.layout.label(text="Inherited Type Quantities:", icon="CON_CHILDOF")
             for qset in ObjectQtosData.data["inherited_qsets"]:
                 draw_psetqto_ui(context, qset["id"], qset, props, self.layout, "Object", allow_removing=False)
 

src/blenderbim/blenderbim/bim/module/root/data.py

@@ -42,6 +42,7 @@ class IfcClassData:
         cls.data["contexts"] = cls.contexts()
         cls.data["has_entity"] = cls.has_entity()
         cls.data["name"] = cls.name()
+        cls.data["has_inherited_predefined_type"] = cls.has_inherited_predefined_type()
         cls.data["ifc_class"] = cls.ifc_class()
         cls.data["ifc_predefined_types"] = cls.ifc_predefined_types()
         cls.data["can_reassign_class"] = cls.can_reassign_class()
@@ -162,6 +163,16 @@ class IfcClassData:
             name += f"[{predefined_type}]"
         return name
 
+    @classmethod
+    def has_inherited_predefined_type(cls):
+        element = tool.Ifc.get_entity(bpy.context.view_layer.objects.active)
+        if not element:
+            return
+        if element_type := ifcopenshell.util.element.get_type(element):
+            # Allow for None due to https://github.com/buildingSMART/IFC4.3.x-development/issues/818
+            return ifcopenshell.util.element.get_predefined_type(element_type) not in ("NOTDEFINED", None)
+        return False
+
     @classmethod
     def ifc_class(cls):
         element = tool.Ifc.get_entity(bpy.context.view_layer.objects.active)

src/blenderbim/blenderbim/bim/module/root/ui.py

@@ -61,7 +61,10 @@ class BIM_PT_class(Panel):
                 self.layout.prop(context.scene.BIMRootProperties, "relating_class_object", icon="COPYDOWN")
             else:
                 row = self.layout.row(align=True)
-                row.label(text=IfcClassData.data["name"])
+                row.label(
+                    text=IfcClassData.data["name"],
+                    icon="CON_CHILDOF" if IfcClassData.data["has_inherited_predefined_type"] else "NONE",
+                )
                 row.operator("bim.select_ifc_class", text="", icon="RESTRICT_SELECT_OFF")
                 row.operator("bim.unlink_object", icon="UNLINKED", text="")
                 if IfcClassData.data["can_reassign_class"]:

src/blenderbim/blenderbim/bim/module/search/operator.py

@@ -235,7 +235,7 @@ class LoadSearch(Operator, tool.Ifc.Operator):
     def _execute(self, context):
         filter_groups = tool.Search.get_filter_groups(self.module)
         group = tool.Ifc.get().by_id(int(context.scene.BIMSearchProperties.saved_searches))
-        query = tool.Search.import_filter_query(tool.Search.get_group_query(group), filter_groups)
+        tool.Search.import_filter_query(tool.Search.get_group_query(group), filter_groups)
 
     def draw(self, context):
         props = context.scene.BIMSearchProperties

src/blenderbim/blenderbim/bim/ui.py

@@ -131,6 +131,8 @@ class BIM_PT_section_with_cappings(Panel):
         box = layout.box()
         header = box.row(align=True)
         header.label(text="Clipping Planes")
+        header.operator("bim.save_clipping_planes", text="", icon="EXPORT")
+        header.operator("bim.load_clipping_planes", text="", icon="IMPORT")
         header.operator("bim.create_clipping_plane", text="", icon="ADD")
 
         box.template_list(
@@ -150,7 +152,7 @@ class BIM_PT_section_with_cappings(Panel):
 
 class BIM_UL_clipping_plane(bpy.types.UIList):
     def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
-        if item:
+        if item and item.obj:
             obj = item.obj
             row = layout.row(align=True)
             row.prop(obj, "name", text="", emboss=False)
@@ -202,6 +204,7 @@ class BIM_ADDON_preferences(bpy.types.AddonPreferences):
         name="Should Make A Cha-Ching Sound When Project Costs Updates", default=False
     )
     lock_grids_on_import: BoolProperty(name="Should Lock Grids By Default", default=True)
+    spatial_elements_unselectable: BoolProperty(name="Should Make Spatial Elements Unselectable By Default", default=True)
     decorations_colour: bpy.props.FloatVectorProperty(
         name="Decorations Colour", subtype="COLOR", default=(1, 1, 1, 1), min=0.0, max=1.0, size=4
     )
@@ -283,6 +286,10 @@ class BIM_ADDON_preferences(bpy.types.AddonPreferences):
         row.prop(self, "should_play_chaching_sound")
         row = layout.row()
         row.prop(self, "lock_grids_on_import")
+        row = layout.row()
+        row.prop(self, "spatial_elements_unselectable")
+
+
 
         row = layout.row()
         row.prop(context.scene.BIMProjectProperties, "should_disable_undo_on_save")

src/blenderbim/blenderbim/core/brick.py

@@ -74,7 +74,7 @@ def assign_brick_reference(ifc, brick, element=None, library=None, brick_uri=Non
     if not reference:
         reference = ifc.run("library.add_reference", library=library)
         ifc.run("library.edit_reference", reference=reference, attributes=brick.export_brick_attributes(brick_uri))
-    ifc.run("library.assign_reference", product=element, reference=reference)
+    ifc.run("library.assign_reference", products=[element], reference=reference)
     project = brick.get_brickifc_project()
     if not project:
         project = brick.add_brickifc_project(brick.get_namespace(brick_uri))

src/blenderbim/blenderbim/core/document.py

@@ -109,8 +109,8 @@ def remove_document(ifc, document_tool, document=None):
 
 
 def assign_document(ifc, product=None, document=None):
-    ifc.run("document.assign_document", product=product, document=document)
+    ifc.run("document.assign_document", products=[product], document=document)
 
 
 def unassign_document(ifc, product=None, document=None):
-    ifc.run("document.unassign_document", product=product, document=document)
+    ifc.run("document.unassign_document", products=[product], document=document)

src/blenderbim/blenderbim/core/drawing.py

@@ -16,6 +16,8 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
+from pathlib import Path
+
 
 def enable_editing_text(drawing, obj=None):
     drawing.enable_editing_text(obj)
@@ -89,6 +91,12 @@ def add_sheet(ifc, drawing, titleblock=None):
     drawing.import_sheets()
 
 
+def regenerate_sheet(drawing, sheet=None):
+    titleblock_uri = drawing.get_document_uri(sheet, "TITLEBLOCK")
+    drawing.create_svg_sheet(sheet, drawing.sanitise_filename(Path(titleblock_uri).stem))
+    drawing.add_drawings(sheet)
+
+
 def open_sheet(drawing, sheet=None):
     drawing.open_layout_svg(drawing.get_document_uri(sheet, "LAYOUT"))
 
@@ -241,7 +249,7 @@ def add_drawing(ifc, collector, drawing, target_view=None, location_hint=None):
         attributes = {"Identification": "X", "Name": drawing_name, "Scope": "DRAWING"}
     ifc.run("document.edit_information", information=information, attributes=attributes)
     ifc.run("document.edit_reference", reference=reference, attributes={"Location": uri})
-    ifc.run("document.assign_document", product=element, document=reference)
+    ifc.run("document.assign_document", products=[element], document=reference)
     drawing.import_drawings()
 
 
@@ -265,7 +273,7 @@ def duplicate_drawing(ifc, drawing_tool, drawing=None, should_duplicate_annotati
             ifc.run("group.assign_group", group=new_group, products=[new_annotation])
 
     old_reference = drawing_tool.get_drawing_document(new_drawing)
-    ifc.run("document.unassign_document", product=new_drawing, document=old_reference)
+    ifc.run("document.unassign_document", products=[new_drawing], document=old_reference)
 
     information = ifc.run("document.add_information")
     uri = drawing_tool.get_default_drawing_path(drawing_name)
@@ -276,7 +284,7 @@ def duplicate_drawing(ifc, drawing_tool, drawing=None, should_duplicate_annotati
         attributes = {"Identification": "X", "Name": drawing_name, "Scope": "DRAWING"}
     ifc.run("document.edit_information", information=information, attributes=attributes)
     ifc.run("document.edit_reference", reference=reference, attributes={"Location": uri})
-    ifc.run("document.assign_document", product=new_drawing, document=reference)
+    ifc.run("document.assign_document", products=[new_drawing], document=reference)
 
     drawing_tool.import_drawings()
     return new_drawing

src/blenderbim/blenderbim/core/library.py

@@ -83,8 +83,8 @@ def edit_library_reference(ifc, library):
 
 
 def assign_library_reference(ifc, obj=None, reference=None):
-    ifc.run("library.assign_reference", product=ifc.get_entity(obj), reference=reference)
+    ifc.run("library.assign_reference", products=[ifc.get_entity(obj)], reference=reference)
 
 
 def unassign_library_reference(ifc, obj=None, reference=None):
-    ifc.run("library.unassign_reference", product=ifc.get_entity(obj), reference=reference)
+    ifc.run("library.unassign_reference", products=[ifc.get_entity(obj)], reference=reference)

src/blenderbim/blenderbim/core/resource.py

@@ -195,7 +195,7 @@ def add_usage_constraint(ifc, resource_tool, resource=None, reference_path=None)
         },
     )
     ifc.run("constraint.add_metric_reference", metric=metric, reference_path=reference_path)
-    ifc.run("constraint.assign_constraint", product=resource, constraint=objective)
+    ifc.run("constraint.assign_constraint", products=[resource], constraint=objective)
 
 
 def remove_usage_constraint(ifc, resource_tool, resource, reference_path):
@@ -206,7 +206,7 @@ def remove_usage_constraint(ifc, resource_tool, resource, reference_path):
             reference = resource_tool.get_metric_reference(metric, is_deep=True)
             if reference == reference_path:
                 ifc.run("constraint.remove_metric", metric=metric)
-                ifc.run("constraint.unassign_constraint", product=resource, constraint=constraint)
+                ifc.run("constraint.unassign_constraint", products=[resource], constraint=constraint)
                 ifc.run("constraint.remove_constraint", constraint=constraint)
 
 

src/blenderbim/blenderbim/core/spatial.py

@@ -32,7 +32,7 @@ def reference_structure(
     element: Optional[ifcopenshell.entity_instance] = None,
 ) -> Union[ifcopenshell.entity_instance, None]:
     if spatial.can_reference(structure, element):
-        return ifc.run("spatial.reference_structure", product=element, relating_structure=structure)
+        return ifc.run("spatial.reference_structure", products=[element], relating_structure=structure)
 
 
 def dereference_structure(
@@ -42,7 +42,7 @@ def dereference_structure(
     element: Optional[ifcopenshell.entity_instance] = None,
 ) -> None:
     if spatial.can_reference(structure, element):
-        return ifc.run("spatial.dereference_structure", product=element, relating_structure=structure)
+        return ifc.run("spatial.dereference_structure", products=[element], relating_structure=structure)
 
 
 def assign_container(

src/blenderbim/blenderbim/tool/collector.py

@@ -187,6 +187,9 @@ class Collector(blenderbim.core.tool.Collector):
             if any(e for e in element.IsNestedBy[0].RelatedObjects if not e.is_a("IfcPort")):
                 return cls._create_own_collection(obj)
 
+        if getattr(element, "HasSurfaceFeatures", None):
+            return cls._create_own_collection(obj)
+
     @classmethod
     def _get_collection(cls, element: ifcopenshell.entity_instance, obj: bpy.types.Object) -> bpy.types.Collection:
         """get or create collection for the element based on it's type"""
@@ -247,6 +250,13 @@ class Collector(blenderbim.core.tool.Collector):
             if collection:
                 return collection
 
+        if element.is_a("IfcSurfaceFeature") and element.file.schema == "IFC4X3":
+            adherend = element.AdheresToElement[0].RelatingElement
+            adherend_obj = tool.Ifc.get_object(adherend)
+            collection = adherend_obj.BIMObjectProperties.collection
+            if collection:
+                return collection
+
         if element.is_a("IfcProject"):
             return bpy.context.scene.collection
 

src/blenderbim/blenderbim/tool/drawing.py

@@ -247,6 +247,21 @@ class Drawing(blenderbim.core.tool.Drawing):
         sheet_builder.create(uri, titleblock)
         return uri
 
+    @classmethod
+    def add_drawings(cls, sheet):
+        sheet_builder = sheeter.SheetBuilder()
+        sheet_builder.data_dir = bpy.context.scene.BIMProperties.data_dir
+        sheet_reference = None
+        drawing_names = []
+        for reference in cls.get_document_references(sheet):
+            if reference.Description == "LAYOUT":
+                sheet_reference = reference
+            elif reference.Description == "DRAWING":
+                drawing_names.append(Path(reference.Location).stem)
+        for annotation in [e for e in tool.Ifc.get().by_type("IfcAnnotation") if e.ObjectType == "DRAWING"]:
+            if annotation.Name in drawing_names:
+                sheet_builder.add_drawing(sheet_reference, annotation, sheet)
+
     @classmethod
     def delete_collection(cls, collection):
         bpy.data.collections.remove(collection, do_unlink=True)
@@ -677,7 +692,7 @@ class Drawing(blenderbim.core.tool.Drawing):
         cls.import_camera_props(drawing, obj)
         tool.Ifc.link(drawing, obj)
 
-        m = shape.transformation.matrix.data
+        m = shape.transformation.matrix
         mat = mathutils.Matrix(
             ([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1])
         )
@@ -733,7 +748,6 @@ class Drawing(blenderbim.core.tool.Drawing):
 
         obj.BIMObjectProperties.ifc_definition_id = ifc_definition_id
 
-
     @classmethod
     def import_drawings(cls):
         props = bpy.context.scene.DocProperties
@@ -1776,7 +1790,6 @@ class Drawing(blenderbim.core.tool.Drawing):
         element_obj_names = set()
         for element in filtered_elements:
             obj = tool.Ifc.get_object(element)
-            element_obj_names.add(obj.name)
             current_representation = tool.Geometry.get_active_representation(obj)
             if current_representation:
                 subcontext = current_representation.ContextOfItems
@@ -1805,10 +1818,14 @@ class Drawing(blenderbim.core.tool.Drawing):
 
             # Don't hide IfcAnnotations as some of them might exist without representations
             if has_context or element.is_a("IfcAnnotation"):
-                # Note that render visibility is only set on drawing generation time for speed.
-                obj.hide_set(False)
+                element_obj_names.add(obj.name)
 
-        [obj.hide_set(False) for obj in bpy.context.view_layer.objects if obj.name not in element_obj_names]
+        # Note that render visibility is only set on drawing generation time for speed.
+        [
+            obj.hide_set(False)  # Show the object
+            for obj in bpy.context.view_layer.objects
+            if obj.name in element_obj_names or not tool.Ifc.get_entity(obj)
+        ]
 
         cls.import_camera_props(drawing, camera)
 

src/blenderbim/blenderbim/tool/geometry.py

@@ -91,6 +91,17 @@ class Geometry(blenderbim.core.tool.Geometry):
         if element.is_a("IfcRelSpaceBoundary"):
             ifcopenshell.api.run("boundary.remove_boundary", tool.Ifc.get(), boundary=element)
             return bpy.data.objects.remove(obj)
+        if element.is_a("IfcGridAxis"):
+            is_last_axis = False
+            # Deleting the last W axis is OK
+            if ((grid := element.PartOfU) and len(grid[0].UAxes) == 1) or (
+                (grid := element.PartOfV) and len(grid[0].VAxes) == 1
+            ):
+                is_last_axis = True
+            if is_last_axis:
+                return
+            ifcopenshell.api.run("grid.remove_grid_axis", tool.Ifc.get(), axis=element)
+            return bpy.data.objects.remove(obj)
 
         collection = obj.BIMObjectProperties.collection
         if collection:
@@ -611,7 +622,7 @@ class Geometry(blenderbim.core.tool.Geometry):
         obj.data.BIMMeshProperties.material_checksum = str([s.id() for s in cls.get_styles(obj) if s])
 
     @classmethod
-    def record_object_position(cls, obj):
+    def record_object_position(cls, obj: bpy.types.Object) -> None:
         # These are recorded separately because they have different numerical tolerances
         obj.BIMObjectProperties.location_checksum = repr(np.array(obj.matrix_world.translation).tobytes())
         obj.BIMObjectProperties.rotation_checksum = repr(np.array(obj.matrix_world.to_3x3()).tobytes())

src/blenderbim/docs/users/other_addons.rst

@@ -29,12 +29,14 @@ Some of these add-ons are not shipped with Blender:
 - `Sverchok <https://github.com/nortikin/sverchok/>`__ - Sverchok is a visual
   programming add-on for Blender that allows you to generate parametric
   geometry, create scripts for non-programmers, model solids from FreeCAD, and
-  much more.
+  much more. There is also
+  `IfcSverchok <https://github.com/IfcOpenShell/IfcOpenShell/blob/v0.7.0/src/ifcsverchok/README.md/>`__ 
+  that adds IFC features to Sverchok.
 - `BlenderGIS <https://github.com/domlysz/BlenderGIS>`__ - BlenderGIS lets you
   import GIS data, grab elevation data from the web, and generate TINs from
   survey points and contours.
 - `Ladybug Tools for Blender
-  <https://blenderbim.org/builds/ladybug-blender-220127.zip>`__ - Ladybug Tools
+  <https://github.com/Andrej730/ladybug-blender/releases/download/ladybug-blender-240419/ladybug-blender-240419.zip>`__ - Ladybug Tools
   is an extension of Sverchok for environmental analysis and building physics
   simulation. It allows analysis of solar, daylight, energy, and CFD.
 - `Topologic <https://topologic.app/>`__ - Perform spatial and topological

src/blenderbim/test/core/test_brick.py

@@ -124,21 +124,21 @@ class TestAssignBrickReference:
         ifc.run("library.add_reference", library="library").should_be_called().will_return("reference")
         brick.export_brick_attributes("brick_uri").should_be_called().will_return("attributes")
         ifc.run("library.edit_reference", reference="reference", attributes="attributes").should_be_called()
-        ifc.run("library.assign_reference", product="element", reference="reference").should_be_called()
+        ifc.run("library.assign_reference", products=["element"], reference="reference").should_be_called()
         brick.get_brickifc_project().should_be_called().will_return("project")
         brick.add_brickifc_reference("brick_uri", "element", "project").should_be_called()
         subject.assign_brick_reference(ifc, brick, element="element", library="library", brick_uri="brick_uri")
 
     def test_assigning_to_an_existing_reference(self, ifc, brick):
         brick.get_library_brick_reference("library", "brick_uri").should_be_called().will_return("reference")
-        ifc.run("library.assign_reference", product="element", reference="reference").should_be_called()
+        ifc.run("library.assign_reference", products=["element"], reference="reference").should_be_called()
         brick.get_brickifc_project().should_be_called().will_return("project")
         brick.add_brickifc_reference("brick_uri", "element", "project").should_be_called()
         subject.assign_brick_reference(ifc, brick, element="element", library="library", brick_uri="brick_uri")
 
     def test_adding_a_brickifc_project_if_it_doesnt_exist(self, ifc, brick):
         brick.get_library_brick_reference("library", "brick_uri").should_be_called().will_return("reference")
-        ifc.run("library.assign_reference", product="element", reference="reference").should_be_called()
+        ifc.run("library.assign_reference", products=["element"], reference="reference").should_be_called()
         brick.get_brickifc_project().should_be_called().will_return(None)
         brick.get_namespace("brick_uri").should_be_called().will_return("namespace")
         brick.add_brickifc_project("namespace").should_be_called().will_return("project")
@@ -277,4 +277,4 @@ class TestSetBrickListRoot:
 class TestRemoveBrickRelation:
     def test_run(self, brick):
         brick.remove_relation("brick_uri", "predicate", "object").should_be_called()
-        subject.remove_brick_relation(brick, brick_uri="brick_uri", predicate="predicate", object="object")
+        subject.remove_brick_relation(brick, brick_uri="brick_uri", predicate="predicate", object="object")

src/blenderbim/test/core/test_document.py

@@ -133,11 +133,11 @@ class TestRemoveDocument:
 
 class TestAssignDocument:
     def test_run(self, ifc):
-        ifc.run("document.assign_document", product="product", document="document").should_be_called()
+        ifc.run("document.assign_document", products=["product"], document="document").should_be_called()
         subject.assign_document(ifc, product="product", document="document")
 
 
 class TestUnassignDocument:
     def test_run(self, ifc):
-        ifc.run("document.unassign_document", product="product", document="document").should_be_called()
+        ifc.run("document.unassign_document", products=["product"], document="document").should_be_called()
         subject.unassign_document(ifc, product="product", document="document")

src/blenderbim/test/core/test_drawing.py

@@ -365,7 +365,7 @@ class TestAddDrawing:
             attributes={"Identification": "X", "Name": "name", "Scope": "DRAWING"},
         ).should_be_called()
         ifc.run("document.edit_reference", reference="reference", attributes={"Location": "uri"}).should_be_called()
-        ifc.run("document.assign_document", product="element", document="reference").should_be_called()
+        ifc.run("document.assign_document", products=["element"], document="reference").should_be_called()
         drawing.import_drawings().should_be_called()
         subject.add_drawing(ifc, collector, drawing, target_view="target_view", location_hint="location_hint")
 
@@ -391,7 +391,7 @@ class TestDuplicateDrawing:
         ifc.run("group.assign_group", group="new_group", products=["new_annotation"]).should_be_called()
 
         drawing.get_drawing_document("new_drawing").should_be_called().will_return("old_reference")
-        ifc.run("document.unassign_document", product="new_drawing", document="old_reference").should_be_called()
+        ifc.run("document.unassign_document", products=["new_drawing"], document="old_reference").should_be_called()
 
         ifc.run("document.add_information").should_be_called().will_return("information")
         ifc.run("document.add_reference", information="information").should_be_called().will_return("reference")
@@ -405,7 +405,7 @@ class TestDuplicateDrawing:
         ifc.run(
             "document.edit_reference", reference="reference", attributes={"Location": "drawing_path"}
         ).should_be_called()
-        ifc.run("document.assign_document", product="new_drawing", document="reference").should_be_called()
+        ifc.run("document.assign_document", products=["new_drawing"], document="reference").should_be_called()
 
         drawing.import_drawings().should_be_called()
         subject.duplicate_drawing(ifc, drawing, drawing="drawing", should_duplicate_annotations=True)

src/blenderbim/test/core/test_library.py

@@ -114,12 +114,12 @@ class TestEditLibraryReference:
 class TestAssignLibraryReference:
     def test_run(self, ifc):
         ifc.get_entity("obj").should_be_called().will_return("product")
-        ifc.run("library.assign_reference", product="product", reference="reference").should_be_called()
+        ifc.run("library.assign_reference", products=["product"], reference="reference").should_be_called()
         subject.assign_library_reference(ifc, obj="obj", reference="reference")
 
 
 class TestUnassignLibraryReference:
     def test_run(self, ifc):
         ifc.get_entity("obj").should_be_called().will_return("product")
-        ifc.run("library.unassign_reference", product="product", reference="reference").should_be_called()
+        ifc.run("library.unassign_reference", products=["product"], reference="reference").should_be_called()
         subject.unassign_library_reference(ifc, obj="obj", reference="reference")

src/blenderbim/test/core/test_spatial.py

@@ -23,14 +23,14 @@ from test.core.bootstrap import ifc, collector, spatial
 class TestReferenceStructure:
     def test_run(self, ifc, spatial):
         spatial.can_reference("structure", "element").should_be_called().will_return(True)
-        ifc.run("spatial.reference_structure", product="element", relating_structure="structure").should_be_called()
+        ifc.run("spatial.reference_structure", products=["element"], relating_structure="structure").should_be_called()
         subject.reference_structure(ifc, spatial, structure="structure", element="element")
 
 
 class TestDereferenceStructure:
     def test_run(self, ifc, spatial):
         spatial.can_reference("structure", "element").should_be_called().will_return(True)
-        ifc.run("spatial.dereference_structure", product="element", relating_structure="structure").should_be_called()
+        ifc.run("spatial.dereference_structure", products=["element"], relating_structure="structure").should_be_called()
         subject.dereference_structure(ifc, spatial, structure="structure", element="element")
 
 

src/blenderbim/test/tool/test_document.py

@@ -18,6 +18,7 @@
 
 import bpy
 import ifcopenshell
+import ifcopenshell.api
 import blenderbim.core.tool
 import blenderbim.tool as tool
 from test.bim.bootstrap import NewFile
@@ -188,7 +189,7 @@ class TestImportReferences(NewFile):
         assert len(props.documents) == 1
         assert props.documents[0].ifc_definition_id == reference.id()
         assert props.documents[0].name == "Unnamed"
-        assert props.documents[0].identification == "*"
+        assert props.documents[0].identification == "X"
         assert props.documents[0].is_information is False
 
 

src/examples/IfcAlignment.cpp

@@ -50,6 +50,7 @@ Schema::IfcProject* setup_project(IfcHierarchyHelper<Schema>& file) {
 
     auto project = file.addProject();
     project->setName(std::string("FHWA Bridge Geometry Manual Example Alignment"));
+    project->setDescription(std::string("C++ Example"));
 
     // set up project units for feet
     // the call to file.addProject() sets up length units as millimeter.
@@ -151,7 +152,7 @@ std::pair<typename Schema::IfcCurveSegment*, typename Schema::IfcAlignmentSegmen
 // creates geometry and business logic segments for vertical profile parabolic vertical curves
 std::pair<typename Schema::IfcCurveSegment*, typename Schema::IfcAlignmentSegment*> create_vcurve(typename Schema::IfcCartesianPoint* p, double start_slope, double end_slope, double length) {
     // geometry
-    double A = 0.0;
+    double A = p->Coordinates()[1];
     double B = start_slope;
     double C = (end_slope - start_slope) / (2 * length);
 
@@ -163,7 +164,7 @@ std::pair<typename Schema::IfcCurveSegment*, typename Schema::IfcAlignmentSegmen
 
     auto curve_segment = new Schema::IfcCurveSegment(
         Schema::IfcTransitionCode::IfcTransitionCode_CONTSAMEGRADIENT,
-        new Schema::IfcAxis2Placement2D(p, new Schema::IfcDirection(std::vector<double>{1.0, 0.0})),
+        new Schema::IfcAxis2Placement2D(p, new Schema::IfcDirection(std::vector<double>{sqrt(1 - start_slope * start_slope), start_slope})),
         new Schema::IfcLengthMeasure(0.0),
         new Schema::IfcLengthMeasure(length),
         parent_curve);
@@ -394,6 +395,7 @@ int main() {
 
     // Zero-length terminator
     auto vertical_terminator_segment = create_gradient(vpoe, -0.5 / 100, 0.0);
+    vertical_terminator_segment.first->setTransition(Schema::IfcTransitionCode::IfcTransitionCode_DISCONTINUOUS);
     vertical_curve_segments->push(vertical_terminator_segment.first);
     vertical_segments->push(vertical_terminator_segment.second);
 
@@ -479,7 +481,10 @@ int main() {
         auto site = file.addSite(project, nullptr);
         site->setName(os.str());
 
-        auto rel_referenced_in_spatial_structure = new Schema::IfcRelReferencedInSpatialStructure(IfcParse::IfcGlobalId(), nullptr, boost::none, boost::none, list_alignments_referenced_in_site, site);
+        std::ostringstream description;
+        description << "Alignments referenced into the spatial structure of Bridge Site " << i;
+
+        auto rel_referenced_in_spatial_structure = new Schema::IfcRelReferencedInSpatialStructure(IfcParse::IfcGlobalId(), nullptr, boost::none, description.str(), list_alignments_referenced_in_site, site);
         file.addEntity(rel_referenced_in_spatial_structure);
     }
 

src/examples/IfcParseExamples.cpp

@@ -119,7 +119,7 @@ void process_pset(element_properties& props, const T* inst) {
 		auto ps = pset->HasProperties();
 		for (auto it = ps->begin(); it != ps->end(); ++it) {
 			auto& p = *it;
-			if (auto singleval = p->as<typename Schema::IfcPropertySingleValue>()) {
+			if (auto singleval = p->template as<typename Schema::IfcPropertySingleValue>()) {
 				std::string propname, propvalue;
 				if constexpr (is_ifc4_or_higher<Schema>::value) {
 					if (!singleval->Name()) {
@@ -133,26 +133,26 @@ void process_pset(element_properties& props, const T* inst) {
 				if (!singleval->NominalValue()) {
 					propvalue = "-";
 				} else {
-					props[*pset->Name()][propname] = format_string(singleval->NominalValue()->as<IfcUtil::IfcBaseClass>()->data().getArgument(0));
+					props[*pset->Name()][propname] = format_string(singleval->NominalValue()->template as<IfcUtil::IfcBaseClass>()->data().getArgument(0));
 				}
 			}
 		}
 	}
-	if (auto qset = inst->as<typename Schema::IfcElementQuantity>()) {
+	if (auto qset = inst->template as<typename Schema::IfcElementQuantity>()) {
 		if (!qset->Name()) {
 			return;
 		}
 		auto qs = qset->Quantities();
 		for (auto it = qs->begin(); it != qs->end(); ++it) {
 			auto& q = *it;
-			if (q->as<typename Schema::IfcPhysicalSimpleQuantity>() && q->data().getArgument(3)->type() == IfcUtil::Argument_DOUBLE) {
+			if (q->template as<typename Schema::IfcPhysicalSimpleQuantity>() && q->data().getArgument(3)->type() == IfcUtil::Argument_DOUBLE) {
 				double v = *q->data().getArgument(3);
 				props[*qset->Name()][q->Name()] = std::to_string(v);
 			}
 		}
 	}
 	if constexpr (is_ifc4_or_higher<Schema>::value) {
-		if (auto extprops = inst->as<Schema::IfcExtendedProperties>()) {
+		if (auto extprops = inst->template as<typename Schema::IfcExtendedProperties>()) {
 			// @todo
 		}
 	}
@@ -161,7 +161,7 @@ void process_pset(element_properties& props, const T* inst) {
 template <typename Schema>
 void get_psets_s(element_properties& props, const typename Schema::IfcObjectDefinition* inst) {
 	// Extracts the property definitions for an IFC instance. 
-	if (auto tyob = inst->as<typename Schema::IfcTypeObject>()) {
+	if (auto tyob = inst->template as<typename Schema::IfcTypeObject>()) {
 		if (tyob->HasPropertySets()) {
 			auto defs = *tyob->HasPropertySets();
 			for (auto it = defs->begin(); it != defs->end(); ++it) {
@@ -171,14 +171,14 @@ void get_psets_s(element_properties& props, const typename Schema::IfcObjectDefi
 		}
 	}
 	if constexpr (is_ifc4_or_higher<Schema>::value) {
-		if (auto mdef = inst->as<typename Schema::IfcMaterialDefinition>()) {
+		if (auto mdef = inst->template as<typename Schema::IfcMaterialDefinition>()) {
 			auto defs = mdef->HasProperties();
 			for (auto it = defs->begin(); it != defs->end(); ++it) {
 				auto& def = *it;
 				process_pset<Schema>(props, def);
 			}
 		}
-		if (auto pdef = inst->as<typename Schema::IfcProfileDef>()) {
+		if (auto pdef = inst->template as<typename Schema::IfcProfileDef>()) {
 			auto defs = pdef->HasProperties();
 			for (auto it = defs->begin(); it != defs->end(); ++it) {
 				auto& def = *it;
@@ -186,7 +186,7 @@ void get_psets_s(element_properties& props, const typename Schema::IfcObjectDefi
 			}
 		}
 	}
-	if (auto ob = inst->as<typename Schema::IfcObject>()) {
+	if (auto ob = inst->template as<typename Schema::IfcObject>()) {
 		if constexpr (is_ifc4_or_higher<Schema>::value) {
 			auto rels = ob->IsTypedBy();
 			for (auto it = rels->begin(); it != rels->end(); ++it) {
@@ -198,9 +198,9 @@ void get_psets_s(element_properties& props, const typename Schema::IfcObjectDefi
 			auto rels = ob->IsDefinedBy();
 			for (auto it = rels->begin(); it != rels->end(); ++it) {
 				auto& rel = *it;
-				if (auto bytype = rel->as<typename Schema::IfcRelDefinesByType>()) {
+				if (auto bytype = rel->template as<typename Schema::IfcRelDefinesByType>()) {
 					get_psets_s<Schema>(props, bytype->RelatingType());
-				} else if (auto byprops = rel->as<typename Schema::IfcRelDefinesByProperties>()) {
+				} else if (auto byprops = rel->template as<typename Schema::IfcRelDefinesByProperties>()) {
 					process_pset<Schema>(props, byprops->RelatingPropertyDefinition());
 				}
 			}

src/examples/IfcSimplifiedAlignment.cpp

@@ -46,6 +46,7 @@ Schema::IfcProject* setup_project(IfcHierarchyHelper<Schema>& file) {
 
     auto project = file.addProject();
     project->setName(std::string("FHWA Bridge Geometry Manual Example Alignment"));
+    project->setDescription(std::string("C++ Example - Simplified"));
 
     // set up project units for feet
     // the call to file.addProject() sets up length units as millimeter.
@@ -150,7 +151,10 @@ int main() {
         auto site = file.addSite(project, nullptr);
         site->setName(os.str());
 
-        auto rel_referenced_in_spatial_structure = new Schema::IfcRelReferencedInSpatialStructure(IfcParse::IfcGlobalId(), nullptr, boost::none, boost::none, list_alignments_referenced_in_site, site);
+        std::ostringstream description;
+        description << "Alignments referenced into the spatial structure of Bridge Site " << i;
+
+        auto rel_referenced_in_spatial_structure = new Schema::IfcRelReferencedInSpatialStructure(IfcParse::IfcGlobalId(), nullptr, boost::none, description.str(), list_alignments_referenced_in_site, site);
         file.addEntity(rel_referenced_in_spatial_structure);
     }
 

src/ifcbimtester/CITATION.cff

@@ -11,7 +11,7 @@ authors:
   - name: "IfcOpenShell contributors"authors:
 repository-code: >-
   https://github.com/IfcOpenShell/IfcOpenShell/tree/v0.7.0/src/ifcbimtester
-url: 'https://blenderbim.org/docs-python/bimtester.html'
+url: 'https://docs.ifcopenshell.org/bimtester.html'
 abstract: Wrapper for Gherkin based unit testing for IFC models
 keywords:
   - Gherkin

src/ifcconvert/IfcConvert.cpp

@@ -814,7 +814,7 @@ int main(int argc, char** argv) {
 		}
 	}
 
-	if (!geometry_settings.get<ifcopenshell::geometry::settings::WeldVertices>().has()) {
+	if (vmap[ifcopenshell::geometry::settings::WeldVertices::name].defaulted()) {
 		geometry_settings.get<ifcopenshell::geometry::settings::WeldVertices>().value = false;
 	}
 
@@ -1508,7 +1508,7 @@ namespace latebound_access {
 			IfcParse::IfcGlobalId guid;
 			latebound_access::set(inst, "GlobalId", (std::string) guid);
 		}
-		return f.addEntity(inst);
+		return &*f.addEntity(inst);
 	}
 }
 

src/ifcgeom/AbstractKernel.cpp

@@ -2,6 +2,7 @@
 
 #include "../ifcgeom/IfcGeomElement.h"
 #include "../ifcgeom/ConversionSettings.h"
+#include "../ifcgeom/abstract_mapping.h"
 
 #ifdef IFOPSH_WITH_OPENCASCADE
 #include "../ifcgeom/kernels/opencascade/OpenCascadeKernel.h"
@@ -38,8 +39,109 @@ const Settings& ifcopenshell::geometry::kernels::AbstractKernel::settings() cons
 	return settings_;
 }
 
-ifcopenshell::geometry::kernels::AbstractKernel* ifcopenshell::geometry::kernels::construct(const std::string& geometry_library, const Settings& conv_settings) {
-	const std::string geometry_library_lower = boost::to_lower_copy(geometry_library);
+
+bool is_valid_for_kernel(const ifcopenshell::geometry::kernels::AbstractKernel* k, const IfcGeom::ConversionResult& shp) {
+#ifdef IFOPSH_WITH_OPENCASCADE
+	if (k->geometry_library() == "opencascade") {
+		return dynamic_cast<ifcopenshell::geometry::OpenCascadeShape*>(shp.Shape().get()) != nullptr;
+	}
+#endif
+#ifdef IFOPSH_WITH_CGAL
+	if (k->geometry_library() == "cgal-simple") {
+		return dynamic_cast<ifcopenshell::geometry::SimpleCgalShape*>(shp.Shape().get()) != nullptr;
+	}
+	if (k->geometry_library() == "cgal") {
+		return dynamic_cast<ifcopenshell::geometry::CgalShape*>(shp.Shape().get()) != nullptr;
+	}
+#endif
+}
+
+class HybridKernel : public ifcopenshell::geometry::kernels::AbstractKernel {
+	std::vector<AbstractKernel*> kernels_;
+	ifcopenshell::geometry::abstract_mapping* mapping_;
+public:
+	HybridKernel(const std::string& name, IfcParse::IfcFile* file, Settings& settings, std::vector<AbstractKernel*> kernels)
+		: AbstractKernel(name, settings)
+		, kernels_(kernels)
+		, mapping_(ifcopenshell::geometry::impl::mapping_implementations().construct(file, settings))
+	{}
+	virtual bool convert(const taxonomy::ptr item, IfcGeom::ConversionResults& rs) {
+		auto ops = mapping_->find_openings(item->instance->as<IfcUtil::IfcBaseEntity>());
+		bool has_openings = ops && ops->size();
+		for (auto& k : kernels_) {
+#ifdef IFOPSH_WITH_CGAL
+			if (has_openings && dynamic_cast<ifcopenshell::geometry::kernels::SimpleCgalKernel*>(k)) {
+				// @todo this would fail later on in the find_openings() call, because we have a
+				// SimpleCgalShape which cannot be used on a kernel that supports booleans.
+				// @todo 1 implement the translation between various conversion result shapes
+				// @todo 2 fold the boolean result openings into the taxonomy item. This should be possible
+				//         now that we have shared_ptr<item> and caching in place. So the inability
+				//         to instance wouldn't matter as much.
+				continue;
+			}
+#endif
+			bool success = false;
+			try {
+				success = k->convert(item, rs);
+			} catch(...) {}
+			if (success) {
+				return true;
+			}
+		}
+		return false;
+	}
+	virtual bool apply_layerset(IfcGeom::ConversionResults& items, const ifcopenshell::geometry::layerset_information& layers) {
+		for (auto& k : kernels_) {
+			bool success = false;
+			try {
+				success = k->apply_layerset(items, layers);
+			} catch (...) {}
+			if (success) {
+				return true;
+			}
+		}
+		return false;
+	}
+	virtual bool apply_folded_layerset(IfcGeom::ConversionResults& items, const ifcopenshell::geometry::layerset_information& layers, const std::map<IfcUtil::IfcBaseEntity*, ifcopenshell::geometry::layerset_information>& folds) {
+		for (auto& k : kernels_) {
+			bool success = false;
+			try {
+				success = k->apply_folded_layerset(items, layers, folds);
+			} catch (...) {}
+			if (success) {
+				return true;
+			}
+		}
+		return false;
+	}
+	virtual bool convert_openings(const IfcUtil::IfcBaseEntity* entity, const std::vector<std::pair<taxonomy::ptr, ifcopenshell::geometry::taxonomy::matrix4>>& openings,
+		const IfcGeom::ConversionResults& entity_shapes, const ifcopenshell::geometry::taxonomy::matrix4& entity_trsf, IfcGeom::ConversionResults& cut_shapes)
+	{
+		for (auto& k : kernels_) {
+			bool is_valid = true;
+			for (auto& s : entity_shapes) {
+				if (!is_valid_for_kernel(k, s)) {
+					is_valid = false;
+					break;
+				}
+			}
+			if (!is_valid) {
+				continue;
+			}
+			bool success = false;
+			try {
+				success = k->convert_openings(entity, openings, entity_shapes, entity_trsf, cut_shapes);
+			} catch (...) {}
+			if (success) {
+				return true;
+			}
+		}
+		return false;
+	}
+};
+
+ifcopenshell::geometry::kernels::AbstractKernel* ifcopenshell::geometry::kernels::construct(IfcParse::IfcFile* file, const std::string& geometry_library, Settings& conv_settings) {
+	std::string geometry_library_lower = boost::to_lower_copy(geometry_library);
 
 #ifdef IFOPSH_WITH_OPENCASCADE
 	if (geometry_library_lower == "opencascade") {
@@ -56,6 +158,44 @@ ifcopenshell::geometry::kernels::AbstractKernel* ifcopenshell::geometry::kernels
 		return new SimpleCgalKernel(conv_settings);
 	}
 #endif
+
+	if (geometry_library_lower.rfind("hybrid-", 0) == 0) {
+		geometry_library_lower = geometry_library_lower.substr(strlen("hybrid"));
+		std::vector<AbstractKernel*> kernels;
+		while (!geometry_library_lower.empty()) {
+			if (geometry_library_lower.find("-", 0) == 0) {
+				geometry_library_lower = geometry_library_lower.substr(strlen("-"));
+			} else {
+				throw IfcParse::IfcException("Invalid hybrid kernel " + geometry_library);
+			}
+			auto n = kernels.size();
+#ifdef IFOPSH_WITH_OPENCASCADE
+			if (geometry_library_lower.find("opencascade", 0) == 0) {
+				kernels.push_back(new IfcGeom::OpenCascadeKernel(conv_settings));
+				geometry_library_lower = geometry_library_lower.substr(strlen("opencascade"));
+			}
+#endif
+
+#ifdef IFOPSH_WITH_CGAL
+			if (geometry_library_lower.find("cgal-simple", 0) == 0) {
+				kernels.push_back(new SimpleCgalKernel(conv_settings));
+				geometry_library_lower = geometry_library_lower.substr(strlen("cgal-simple"));
+			}
+
+			if (geometry_library_lower.find("cgal", 0) == 0) {
+				kernels.push_back(new CgalKernel(conv_settings));
+				geometry_library_lower = geometry_library_lower.substr(strlen("cgal"));
+			}
+#endif
+			if (kernels.size() != n + 1) {
+				throw IfcParse::IfcException("Invalid hybrid kernel " + geometry_library);
+			}
+		}
+
+		if (!kernels.empty()) {
+			return new HybridKernel(geometry_library, file, conv_settings, kernels);
+		}
+	}
 	
 	throw IfcParse::IfcException("No geometry kernel registered for " + geometry_library);
 }

src/ifcgeom/AbstractKernel.h

@@ -19,16 +19,19 @@ namespace ifcopenshell { namespace geometry { namespace kernels {
 
 	class IFC_GEOM_API AbstractKernel {
 	protected:
-		std::string geometry_library;
+		std::string geometry_library_;
 		Settings settings_;
 
 	public:
 		AbstractKernel(const std::string& geometry_library, const Settings& settings)
-			: geometry_library(geometry_library)
+			: geometry_library_(geometry_library)
 			, settings_(settings) {}
 
-		bool convert(const taxonomy::ptr, IfcGeom::ConversionResults&);
+		virtual bool convert(const taxonomy::ptr, IfcGeom::ConversionResults&);
 		const Settings& settings() const;
+		const std::string& geometry_library() const {
+			return geometry_library_;
+		}
 
 		virtual bool convert_impl(const taxonomy::matrix4::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
 		virtual bool convert_impl(const taxonomy::point3::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
@@ -50,6 +53,7 @@ namespace ifcopenshell { namespace geometry { namespace kernels {
 		virtual bool convert_impl(const taxonomy::revolve::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
 		virtual bool convert_impl(const taxonomy::bspline_surface::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
 		virtual bool convert_impl(const taxonomy::cylinder::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
+		virtual bool convert_impl(const taxonomy::sphere::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
 		virtual bool convert_impl(const taxonomy::solid::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
 		virtual bool convert_impl(const taxonomy::surface_curve_sweep::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
 		virtual bool convert_impl(const taxonomy::loft::ptr, IfcGeom::ConversionResults&) { throw std::runtime_error("Not implemented"); }
@@ -68,7 +72,7 @@ namespace ifcopenshell { namespace geometry { namespace kernels {
 
 	};
 
-	AbstractKernel* construct(const std::string& geometry_library, const Settings& conv_settings);
+	AbstractKernel* construct(IfcParse::IfcFile* file, const std::string& geometry_library, Settings& conv_settings);
 
 }
 }

src/ifcgeom/ConversionSettings.h

@@ -187,6 +187,13 @@ namespace ifcopenshell {
 				static constexpr bool defaultvalue = false;
 			};
 
+			struct UseMaterialNames : public SettingBase<UseMaterialNames, bool> {
+				static constexpr const char* const name = "use-material-names";
+				static constexpr const char* const description = "Use material names instead of unique IDs for naming materials upon serialization. "
+					"Applicable for OBJ and DAE output.";
+				static constexpr bool defaultvalue = false;
+			};
+
 			struct ConvertBackUnits : public SettingBase<ConvertBackUnits, bool> {
 				static constexpr const char* const name = "convert-back-units";
 				static constexpr const char* const description = "Specifies whether to convert back geometrical output back to the "
@@ -221,7 +228,7 @@ namespace ifcopenshell {
 			struct OutputDimensionality : public SettingBase<OutputDimensionality, OutputDimensionalityTypes> {
 				static constexpr const char* const name = "dimensionality";
 				static constexpr const char* const description = "Specifies whether to include curves and/or surfaces and solids in the output result. Defaults to only surfaces and solids.";
-				static constexpr OutputDimensionalityTypes defaultvalue = CURVES_SURFACES_AND_SOLIDS;
+				static constexpr OutputDimensionalityTypes defaultvalue = SURFACES_AND_SOLIDS;
 			};
 
 			enum IteratorOutputOptions {
@@ -373,6 +380,13 @@ namespace ifcopenshell {
 			template <std::size_t Index>
 			void set_option_(const std::string& name, const value_variant_t& val) {
 				if (std::tuple_element_t<Index, settings_t>::name == name) {
+					if constexpr (std::is_enum_v<typename std::tuple_element_t<Index, settings_t>::base_type>) {
+						if (val.which() == 1) {
+							auto val_as_enum = (typename std::tuple_element_t<Index, settings_t>::base_type) boost::get<int>(val);
+							std::get<Index>(settings).value = val_as_enum;
+							return;
+						}
+					}
 					std::get<Index>(settings).value = boost::get<typename std::tuple_element_t<Index, settings_t>::base_type>(val);
 				} else if constexpr (Index + 1 < std::tuple_size_v<settings_t>) {
 					set_option_<Index + 1>(name, val);
@@ -426,7 +440,7 @@ namespace ifcopenshell {
 		};
 
 		class IFC_GEOM_API Settings : public SettingsContainer<
-                                          std::tuple<MesherLinearDeflection, MesherAngularDeflection, ReorientShells, LengthUnit, PlaneUnit, Precision, OutputDimensionality, LayersetFirst, DisableBooleanResult, NoWireIntersectionCheck, NoWireIntersectionTolerance, PrecisionFactor, DebugBooleanOperations, BooleanAttempt2d, WeldVertices, UseWorldCoords, ConvertBackUnits, ContextIds, ContextTypes, ContextIdentifiers, IteratorOutput, DisableOpeningSubtractions, ApplyDefaultMaterials, DontEmitNormals, GenerateUvs, ApplyLayerSets, UseElementHierarchy, ValidateQuantities, EdgeArrows, BuildingLocalPlacement, SiteLocalPlacement, ForceSpaceTransparency, CircleSegments, KeepBoundingBoxes, PiecewiseStepType, PiecewiseStepParam>
+                                          std::tuple<MesherLinearDeflection, MesherAngularDeflection, ReorientShells, LengthUnit, PlaneUnit, Precision, OutputDimensionality, LayersetFirst, DisableBooleanResult, NoWireIntersectionCheck, NoWireIntersectionTolerance, PrecisionFactor, DebugBooleanOperations, BooleanAttempt2d, WeldVertices, UseWorldCoords, UseMaterialNames, ConvertBackUnits, ContextIds, ContextTypes, ContextIdentifiers, IteratorOutput, DisableOpeningSubtractions, ApplyDefaultMaterials, DontEmitNormals, GenerateUvs, ApplyLayerSets, UseElementHierarchy, ValidateQuantities, EdgeArrows, BuildingLocalPlacement, SiteLocalPlacement, ForceSpaceTransparency, CircleSegments, KeepBoundingBoxes, PiecewiseStepType, PiecewiseStepParam>
 		>
 		{};
 }

src/ifcgeom/Converter.cpp

@@ -9,7 +9,7 @@ ifcopenshell::geometry::Converter::Converter(const std::string& geometry_library
 	, settings_(s)
 {
 	mapping_ = impl::mapping_implementations().construct(file, settings_);
-	kernel_ = kernels::construct(geometry_library, mapping_->settings());
+	kernel_ = kernels::construct(file, geometry_library, mapping_->settings());
 }
 
 namespace {

src/ifcgeom/GeometrySerializer.h

@@ -49,13 +49,6 @@ inline namespace settings {
 		static constexpr bool defaultvalue = false;
 	};
 
-	struct UseMaterialNames : public SettingBase<UseMaterialNames, bool> {
-		static constexpr const char* const name = "use-material-names";
-		static constexpr const char* const description = "Use material names instead of unique IDs for naming materials upon serialization. "
-					"Applicable for OBJ and DAE output.";
-		static constexpr bool defaultvalue = false;
-	};
-
 	struct UseElementTypes : public SettingBase<UseElementTypes, bool> {
 		static constexpr const char* const name = "use-element-types";
 		static constexpr const char* const description = "Use element types instead of unique IDs for naming elements upon serialization. "

src/ifcgeom/abstract_mapping.h

@@ -44,6 +44,7 @@ namespace geometry {
 		virtual IfcUtil::IfcBaseEntity* representation_of(const IfcUtil::IfcBaseEntity* product) = 0;
 
 		const Settings& settings() const { return settings_; }
+		Settings& settings() { return settings_; }
     };
 
 	namespace impl {

src/ifcgeom/kernels/opencascade/solid.cpp

@@ -24,6 +24,7 @@
 #include <BRepPrimAPI_MakePrism.hxx>
 #include <BRepAlgoAPI_Common.hxx>
 #include <ShapeFix_Solid.hxx>
+#include <BRepPrimAPI_MakeSphere.hxx>
 
 using namespace ifcopenshell::geometry;
 using namespace ifcopenshell::geometry::kernels;
@@ -64,18 +65,34 @@ bool OpenCascadeKernel::convert(const taxonomy::solid::ptr solid, TopoDS_Shape&
 
 		result = halfspace;
 		return true;
+	} else if (solid->children.size() == 1 
+		&& solid->children[0]->children.size() == 1 
+		&& solid->children[0]->children[0]->basis
+		&& solid->children[0]->children[0]->basis->kind() == taxonomy::SPHERE)
+	{
+		auto sphere = taxonomy::cast<taxonomy::sphere>(solid->children[0]->children[0]->basis);
+		gp_GTrsf gtrsf;
+		convert(sphere->matrix, gtrsf);
+		BRepPrimAPI_MakeSphere builder(sphere->radius);
+		auto s = builder.Solid();
+		s.Move(gtrsf.Trsf());
+		result = s;
+		return true;
 	}
 
 	for (auto& s : solid->children) {
 		TopoDS_Shape shl;
-		convert(s, shl);
-		if (shl.ShapeType() == TopAbs_SHELL) {
-			ShapeFix_Solid solid;
-			S = solid.SolidFromShell(TopoDS::Shell(shl));
-		} else if (solid->children.size() == 1) {
-			S = shl;
+		if (convert(s, shl)) {
+			if (shl.ShapeType() == TopAbs_SHELL) {
+				ShapeFix_Solid solid;
+				S = solid.SolidFromShell(TopoDS::Shell(shl));
+			} else if (solid->children.size() == 1) {
+				S = shl;
+			} else {
+				throw std::runtime_error("Unexpected configuration of subshapes");
+			}
 		} else {
-			throw std::runtime_error("Unexpected configuration of subshapes");
+			Logger::Warning("Ignored shell", s->instance);
 		}
 	}
 	if (!S.IsNull()) {

src/ifcgeom/mapping/IfcCompositeCurve.cpp

@@ -23,7 +23,7 @@ using namespace ifcopenshell::geometry;
 
 taxonomy::ptr mapping::map_impl(const IfcSchema::IfcCompositeCurve* inst) {
 	auto loop = taxonomy::make<taxonomy::loop>();
-	auto pwf = taxonomy::make<taxonomy::piecewise_function>(&settings_);
+	std::vector<taxonomy::piecewise_function::ptr> pwfs;
 
 #ifdef SCHEMA_HAS_IfcSegment
 	// 4x3
@@ -31,7 +31,7 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcCompositeCurve* inst) {
 #else
 	IfcSchema::IfcCompositeCurveSegment::list::ptr segments = inst->Segments();
 #endif
-
+	
 	for (auto& segment : *segments) {
 		if (segment->as<IfcSchema::IfcCompositeCurveSegment>() && segment->as<IfcSchema::IfcCompositeCurveSegment>()->ParentCurve()->as<IfcSchema::IfcLine>()) {
 			Logger::Notice("Infinite IfcLine used as ParentCurve of segment, treating as a segment", segment);
@@ -71,20 +71,21 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcCompositeCurve* inst) {
 		else if (segment->as<IfcSchema::IfcCurveSegment>()) {
 			// @todo check that we don't get a mixture of implicit and explicit definitions
 			auto crv = map(segment->as<IfcSchema::IfcCurveSegment>());
-			if (crv->kind() == taxonomy::LOOP) {
+			if (crv && crv->kind() == taxonomy::LOOP) {
 				for (auto& s : taxonomy::cast<taxonomy::loop>(crv)->children) {
 					loop->children.push_back(s);
 				}
 			}
-			else if (crv->kind() == taxonomy::PIECEWISE_FUNCTION) {
-				auto seg = taxonomy::cast<taxonomy::piecewise_function>(crv);
-				pwf->spans.insert(pwf->spans.end(), seg->spans.begin(), seg->spans.end());
+			else if (crv && crv->kind() == taxonomy::PIECEWISE_FUNCTION) {
+            pwfs.push_back(taxonomy::cast<taxonomy::piecewise_function>(crv));
+			} else if (!crv) {
+				return nullptr;
 			}
 		}
 #endif
 	}
 
-	if (pwf->spans.empty()) {
+	if (pwfs.empty()) {
 		aggregate_of_instance::ptr profile = inst->data().getInverse(&IfcSchema::IfcProfileDef::Class(), -1);
 		const bool force_close = profile && profile->size() > 0;
 		loop->closed = force_close;
@@ -92,7 +93,7 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcCompositeCurve* inst) {
 		return loop;
 	}
 	else {
-		pwf->instance = inst;
+      auto pwf = taxonomy::make<taxonomy::piecewise_function>(pwfs,&settings_,inst);
 		return pwf;
 	}
 }

src/ifcgeom/mapping/IfcFixedReferenceSweptAreaSolid.cpp

@@ -67,11 +67,13 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcFixedReferenceSweptAreaSolid
 		for (size_t i = 0; i <= num_steps; ++i) {
 			auto m4 = pwf->evaluate(start + curve_length / num_steps * i);
 			
+			/*
 			std::stringstream ss;
 			ss << m4;
 			auto s = ss.str();
 			std::wcout << s.c_str() << std::endl;
             std::wcout << "determinant: " << m4.determinant() << std::endl;
+			*/
 
 			Eigen::Matrix4d m4b = Eigen::Matrix4d::Identity();
 			bool is_directrix_derived = false;

src/ifcgeom/mapping/IfcGradientCurve.cpp

@@ -28,17 +28,17 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcGradientCurve* inst) {
        Logger::Warning("Expected IfcGradientCurve.BaseCurve to be IfcCompositeCurve", inst); // CT 4.1.7.1.1.2
 
    auto horizontal = taxonomy::cast<taxonomy::piecewise_function>(map(inst->BaseCurve()));
-	auto vertical = taxonomy::make<taxonomy::piecewise_function>(&settings_);
 
 	auto segments = inst->Segments();
 
+    std::vector<taxonomy::piecewise_function::ptr> pwfs;
+
 	for (auto& segment : *segments) {
 		if (segment->as<IfcSchema::IfcCurveSegment>()) {
 			// @todo check that we don't get a mixture of implicit and explicit definitions
 			auto crv = map(segment->as<IfcSchema::IfcCurveSegment>());
-			if (crv->kind() == taxonomy::PIECEWISE_FUNCTION) {
-				auto seg = taxonomy::cast<taxonomy::piecewise_function>(crv);
-				vertical->spans.insert(vertical->spans.end(), seg->spans.begin(), seg->spans.end());
+			if (crv && crv->kind() == taxonomy::PIECEWISE_FUNCTION) {
+				pwfs.push_back(taxonomy::cast<taxonomy::piecewise_function>(crv));
 			} else {
 				Logger::Error("Unsupported");
 				return nullptr;
@@ -48,6 +48,8 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcGradientCurve* inst) {
 			return nullptr;
 		}
 	}
+  
+	auto vertical = taxonomy::make<taxonomy::piecewise_function>(pwfs,&settings_);
 
 	auto composition = [horizontal, vertical](double u)->Eigen::Matrix4d {
 		auto xy = horizontal->evaluate(u);
@@ -62,26 +64,12 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcGradientCurve* inst) {
       return m;
 	};
 
-	std::array<taxonomy::piecewise_function::ptr, 2> both = { horizontal , vertical };
-	// @todo: rb - this constrains the range of u to the minimum of horizontal and vertical
-	// we discussed using the maximum for the range of us and then using std::numeric_limits<double>::NAN
-	// for values of u that horizontal or vertical cannot be computed.
-	// Review and decide what to do.
-	double min_length = std::numeric_limits<double>::infinity();
-	for (auto i = 0; i < 2; ++i) {
-		double l = 0;
-		for (auto& s : both[i]->spans) {
-			l += s.first;
-		}
-		if (l < min_length) {
-			min_length = l;
-		}
-	}
+   double min_length = std::min(horizontal->length(), vertical->length());
 
-	auto pwf = taxonomy::make<taxonomy::piecewise_function>(&settings_);
-	pwf->spans.emplace_back( min_length, composition );
-	pwf->instance = inst;
-	return pwf;
+	taxonomy::piecewise_function::spans spans;
+   spans.emplace_back(min_length, composition);
+   auto pwf = taxonomy::make<taxonomy::piecewise_function>(spans, &settings_, inst);
+   return pwf;
 }
 
 #endif

src/ifcgeom/mapping/IfcOffsetCurveByDistance.cpp

@@ -42,7 +42,7 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcOffsetCurveByDistances* inst
     auto pw_curve = taxonomy::dcast<taxonomy::piecewise_function>(map(basis_curve));
     double basis_curve_length = pw_curve->length();
 
-    auto offsets = taxonomy::make<taxonomy::piecewise_function>(&settings_);
+    taxonomy::piecewise_function::spans offset_spans;
 
 #if defined SCHEMA_HAS_IfcDistanceExpression
    double first_distance = first_offset_value->DistanceAlong();
@@ -63,12 +63,12 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcOffsetCurveByDistances* inst
         py *= length_unit_;
         pz *= length_unit_;
         
-        auto fn = [py, pz](double u) -> Eigen::Matrix4d { 
+        auto fn = [py, pz](double /*u*/) -> Eigen::Matrix4d { 
            Eigen::Matrix4d m = Eigen::Matrix4d::Identity(); 
            m.col(3)(1) = py; 
            m.col(3)(2) = pz; 
            return m; };
-        offsets->spans.push_back({first_distance, fn});
+        offset_spans.emplace_back(first_distance, fn);
 	}
 
     auto iter = offset_values->begin();
@@ -112,7 +112,7 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcOffsetCurveByDistances* inst
             m.col(3)(2) = (l == 0.0 ? zp : (zp + (zn - zp) * u / l));
             return m;
         };
-		  offsets->spans.push_back({l, fn});
+        offset_spans.emplace_back(l, fn);
     }
 
 	 // at this point, next == end and prev == end-1
@@ -134,15 +134,17 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcOffsetCurveByDistances* inst
          py *= length_unit_;
          pz *= length_unit_;
          double l = basis_curve_length - last_distance;
-         auto fn = [py, pz](double u) -> Eigen::Matrix4d { 
+         auto fn = [py, pz](double /*u*/) -> Eigen::Matrix4d { 
             Eigen::Matrix4d m = Eigen::Matrix4d::Identity(); 
             m.col(3)(1) = py; 
             m.col(3)(2) = pz; 
             return m; };
 
-         offsets->spans.push_back({l, fn});
+         offset_spans.emplace_back(l, fn);
     }
 
+   auto offsets = taxonomy::make<taxonomy::piecewise_function>(offset_spans,&settings_);
+
 	auto composition = [pw_curve, offsets](double u) -> Eigen::Matrix4d {
       auto p = pw_curve->evaluate(u);
 		auto offset = offsets->evaluate(u);
@@ -152,9 +154,9 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcOffsetCurveByDistances* inst
 
    // current implementation assumes that composition is equal to the full length of basis curve
    // this may change depending on decisions in the bSI-IF
-	auto pwf = taxonomy::make<taxonomy::piecewise_function>(&settings_);
-	pwf->spans.emplace_back( basis_curve_length, composition );
-	pwf->instance = inst;
+   taxonomy::piecewise_function::spans spans;
+   spans.emplace_back(basis_curve_length, composition);
+	auto pwf = taxonomy::make<taxonomy::piecewise_function>(spans,&settings_,inst);
 	return pwf;
 }
 

src/ifcgeom/mapping/IfcRepresentation.cpp

@@ -22,8 +22,7 @@
 using namespace ifcopenshell::geometry;
 
 taxonomy::ptr mapping::map_impl(const IfcSchema::IfcRepresentation* inst) {
-	// @todo
-	const bool use_body = !this->settings_.get<settings::IncludeCurves>().get();
+	auto items_to_include = this->settings_.get<settings::OutputDimensionality>().get();
 
 	auto items = map_to_collection(this, inst->Items());
 	if (!items) {
@@ -42,9 +41,15 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcRepresentation* inst) {
 	// @todo
 	// if (s.ShapeType() == TopAbs_COMPOUND && TopoDS_Iterator(s).More() && TopoDS_Iterator(s).Value().ShapeType() == TopAbs_SOLID) {
 
-	auto filtered = filter_in_place(items, [&use_body](taxonomy::ptr i) {
-		// @todo just filter loops for now.
-		return (i->kind() != taxonomy::LOOP && i->kind() != taxonomy::PIECEWISE_FUNCTION) == use_body;
+	auto filtered = filter_in_place(items, [&items_to_include](taxonomy::ptr i) {
+		auto is_curve = (i->kind() == taxonomy::EDGE || i->kind() == taxonomy::LOOP || i->kind() == taxonomy::PIECEWISE_FUNCTION);
+		if (is_curve && items_to_include == settings::SURFACES_AND_SOLIDS) {
+			return false;
+		} else if (!is_curve && items_to_include == settings::CURVES) {
+			return false;
+		} else {
+			return true;
+		}
 	});
 
 	if (filtered->children.empty()) {

src/ifcgeom/mapping/IfcSegmentedReferenceCurve.cpp

@@ -28,17 +28,16 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSegmentedReferenceCurve* ins
        Logger::Warning("Expected IfcSegmentedReferenceCurve.BaseCurve to be IfcGradient", inst); // CT 4.1.7.1.1.3
 		  
 	auto gradient = taxonomy::cast<taxonomy::piecewise_function>(map(inst->BaseCurve()));
-	auto cant = taxonomy::make<taxonomy::piecewise_function>(&settings_);
-
+	
 	auto segments = inst->Segments();
 
-	for (auto& segment : *segments) {
+    std::vector<taxonomy::piecewise_function::ptr> pwfs;
+    for (auto& segment : *segments) {
 		if (segment->as<IfcSchema::IfcCurveSegment>()) {
 			// @todo check that we don't get a mixture of implicit and explicit definitions
 			auto crv = map(segment->as<IfcSchema::IfcCurveSegment>());
-			if (crv->kind() == taxonomy::PIECEWISE_FUNCTION) {
-				auto seg = taxonomy::cast<taxonomy::piecewise_function>(crv);
-				cant->spans.insert(cant->spans.end(), seg->spans.begin(), seg->spans.end());
+			if (crv && crv->kind() == taxonomy::PIECEWISE_FUNCTION) {
+				pwfs.push_back(taxonomy::cast<taxonomy::piecewise_function>(crv));
 			} else {
 				Logger::Error("Unsupported");
 				return nullptr;
@@ -48,6 +47,7 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSegmentedReferenceCurve* ins
 			return nullptr;
 		}
 	}
+   auto cant = taxonomy::make<taxonomy::piecewise_function>(pwfs,&settings_);
 
 	auto composition = [gradient, cant](double u)->Eigen::Matrix4d {
 		auto g = gradient->evaluate(u);
@@ -62,26 +62,12 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSegmentedReferenceCurve* ins
       return m;
 	};
 
-	std::array<taxonomy::piecewise_function::ptr, 2> both = { gradient , cant };
-	// @todo: rb - this constrains the range of u to the minimum of gradient and cant
-	// we discussed using the maximum for the range of us and then using std::numeric_limits<double>::NAN
-	// for values of u that gradient or cant cannot be computed.
-	// Review and decide what to do.
-	double min_length = std::numeric_limits<double>::infinity();
-	for (auto i = 0; i < 2; ++i) {
-		double l = 0;
-		for (auto& s : both[i]->spans) {
-			l += s.first;
-		}
-		if (l < min_length) {
-			min_length = l;
-		}
-	}
+   double min_length = std::min(gradient->length(), cant->length());
 
-	auto pwf = taxonomy::make<taxonomy::piecewise_function>(&settings_);
-	pwf->spans.emplace_back( min_length, composition );
-	pwf->instance = inst;
-	return pwf;
+	taxonomy::piecewise_function::spans spans;
+   spans.emplace_back(min_length, composition);
+   auto pwf = taxonomy::make<taxonomy::piecewise_function>(spans, &settings_, inst);
+   return pwf;
 }
 
 #endif

src/ifcgeom/mapping/IfcSphere.cpp

@@ -22,18 +22,14 @@
 using namespace ifcopenshell::geometry;
 
 taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSphere* inst) {
-	// @todo
-	return nullptr;
-	/*
-	const double r = inst->Radius() * length_unit_;
-	
-	BRepPrimAPI_MakeSphere builder(r);
-	gp_Trsf trsf;
-	IfcGeom::Kernel::convert(inst->Position(),trsf);
-	
-	// IfcCsgPrimitive3D.Position has unit scale factor
-	shape = builder.Solid().Moved(trsf);
-
-	return true;
-	*/
+	auto sol = taxonomy::make<taxonomy::solid>();
+	auto shl = taxonomy::make<taxonomy::shell>();
+	auto fac = taxonomy::make<taxonomy::face>();
+	auto spr = taxonomy::make<taxonomy::sphere>();
+	spr->matrix = taxonomy::cast<taxonomy::matrix4>(map(inst->Position()));
+	spr->radius = inst->Radius() * length_unit_;
+	fac->basis = spr;
+	shl->children.push_back(fac);
+	sol->children.push_back(shl);
+	return sol;
 }

src/ifcgeom/mapping/bind_convert_impl.i

@@ -11,7 +11,7 @@
 				try { \
 					if (inst->as<IfcSchema::IfcRepresentationItem>() && !inst->as<IfcSchema::IfcStyledItem>() && \
 						/* @todo */ \
-						(item->kind() == taxonomy::SHELL || item->kind() == taxonomy::COLLECTION || item->kind() == taxonomy::EXTRUSION) \
+						(item->kind() == taxonomy::SOLID || item->kind() == taxonomy::SHELL || item->kind() == taxonomy::COLLECTION || item->kind() == taxonomy::EXTRUSION) \
 					) { \
 						auto style = find_style(inst->as<IfcSchema::IfcRepresentationItem>()); \
 						if (style) { \

src/ifcgeom/mapping/mapping.cpp

@@ -153,9 +153,20 @@ bool mapping::reuse_ok_(const IfcSchema::IfcProduct::list::ptr& products) {
 }
 
 aggregate_of_instance::ptr mapping::find_openings(const IfcUtil::IfcBaseEntity* inst) {
+	aggregate_of_instance::ptr openings(new aggregate_of_instance);
+	
+	if (auto rep = inst->as<IfcSchema::IfcRepresentation>()) {
+		// @todo this is essentially only for hybrid kernel trying to guess
+		// when not to use a simple kernel.
+		auto prods = products_represented_by(rep, true);
+		for (auto& p : *prods) {
+			openings->push(find_openings(p));
+		}
+		return openings;
+	}
+
 	auto product = inst->as<IfcSchema::IfcProduct>();
 
-	aggregate_of_instance::ptr openings(new aggregate_of_instance);
 	if (product->as<IfcSchema::IfcElement>() && !product->as<IfcSchema::IfcFeatureElementSubtraction>()) {
 		const IfcSchema::IfcElement* element = product->as<IfcSchema::IfcElement>();
 		auto rels = element->HasOpenings();
@@ -426,6 +437,14 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcMaterial* material) {
 	}
 
 	taxonomy::style::ptr material_style = taxonomy::make<taxonomy::style>();
+	material_style->instance = material;
+	if (settings_.get<settings::UseMaterialNames>().get()) {
+		material_style->name = material->Name();
+	} else {
+		std::ostringstream oss;
+		oss << material->declaration().name() << "-" << material->data().id();
+		material_style->name = oss.str();
+	}
 	return material_style;
 
 	// @todo
@@ -448,8 +467,12 @@ taxonomy::ptr mapping::map_impl(const IfcSchema::IfcStyledItem* inst) {
 	taxonomy::style::ptr surface_style = taxonomy::make<taxonomy::style>();
 
 	surface_style->instance = style;
-	if (style->Name()) {
+	if (settings_.get<settings::UseMaterialNames>().get() && style->Name()) {
 		surface_style->name = *style->Name();
+	} else {
+		std::ostringstream oss;
+		oss << shading->declaration().name() << "-" << shading->data().id();
+		surface_style->name = oss.str();
 	}
 	
 	double rgb[3];
@@ -952,7 +975,7 @@ void mapping::addRepresentationsFromDefaultContexts(IfcSchema::IfcRepresentation
 	allowed_context_types.insert("notdefined");
 
 	std::set<std::string> context_types;
-	if (settings_.get<settings::IncludeSurfaces>().get()) {
+	if (this->settings_.get<settings::OutputDimensionality>().get() != settings::CURVES) {
 		// Really this should only be 'Model', as per
 		// the standard 'Design' is deprecated. So,
 		// just for backwards compatibility:
@@ -962,7 +985,7 @@ void mapping::addRepresentationsFromDefaultContexts(IfcSchema::IfcRepresentation
 		context_types.insert("model view");
 		context_types.insert("detail view");
 	}
-	if (settings_.get<settings::IncludeCurves>().get()) {
+	if (this->settings_.get<settings::OutputDimensionality>().get() != settings::SURFACES_AND_SOLIDS) {
 		context_types.insert("plan");
 	}
 
@@ -1051,7 +1074,7 @@ IfcUtil::IfcBaseEntity* mapping::representation_of(const IfcUtil::IfcBaseEntity*
 		}
 	}
 
-	if (intersection->size() == 0 && settings_.get<settings::ContextIds>().has() && settings_.get<settings::IncludeCurves>().get() && !settings_.get<settings::IncludeSurfaces>().get()) {
+	if (intersection->size() == 0 && settings_.get<settings::ContextIds>().has() && this->settings_.get<settings::OutputDimensionality>().get() == settings::CURVES) {
 		for (auto& r : *of_product) {
 			if (r->RepresentationIdentifier() && *r->RepresentationIdentifier() == "Axis") {
 				intersection->push(r);

src/ifcgeom/profile_helper.cpp

@@ -99,7 +99,7 @@ taxonomy::loop::ptr ifcopenshell::geometry::profile_helper(const taxonomy::matri
 	}
 	*/
 
-	const bool has_position = !m4->is_identity();
+	const bool has_position = m4 && !m4->is_identity();
 
 	// @todo precision
 

src/ifcgeom/taxonomy.cpp

@@ -149,6 +149,10 @@ namespace {
 		throw std::runtime_error("not implemented");
 	}
 
+	bool compare(const sphere&, const sphere&) {
+		throw std::runtime_error("not implemented");
+	}
+
 	bool compare(const surface_curve_sweep&, const surface_curve_sweep&) {
 		throw std::runtime_error("not implemented");
 	}
@@ -467,37 +471,67 @@ ifcopenshell::geometry::taxonomy::item::ptr ifcopenshell::geometry::taxonomy::pi
    } else {
 	   // parameter is minimum number of steps
        num_steps = (unsigned)std::ceil(param);
-    }
+   }
 
 	return evaluate(0.0, curve_length, num_steps);
 }
 
 item::ptr ifcopenshell::geometry::taxonomy::piecewise_function::evaluate(double ustart, double uend,unsigned nsteps) const {
+    return evaluate2(ustart, uend, nsteps).first;
+}
+
+std::pair<item::ptr, std::vector<double>> ifcopenshell::geometry::taxonomy::piecewise_function::evaluate2(double ustart, double uend, unsigned nsteps) const {
     double curve_length = length();
     ustart = std::max(0.0, ustart);
     uend = std::min(uend, curve_length);
 
- 	 auto resolution = (uend - ustart)/ nsteps;
+    auto resolution = (uend - ustart) / nsteps;
 
     std::vector<taxonomy::point3::ptr> polygon;
+    std::vector<double> u_values;
+    polygon.reserve(nsteps);
+    u_values.reserve(nsteps);
 
-    for (int i = 0; i <= nsteps; ++i) {
+    for (unsigned i = 0; i <= nsteps; ++i) {
         auto u = resolution * i + ustart;
+        u_values.push_back(u);
         Eigen::Matrix4d m = evaluate(u);
         polygon.push_back(taxonomy::make<taxonomy::point3>(m.col(3)(0), m.col(3)(1), m.col(3)(2)));
     }
 
-    return polygon_from_points(polygon);
+    return {polygon_from_points(polygon), u_values};
 }
 
 Eigen::Matrix4d ifcopenshell::geometry::taxonomy::piecewise_function::evaluate(double u) const {
-   // @todo: rb optimize, assume monotonic evaluation and store last evaluated segment?
-   for (auto& [length, fn] : spans) {
-   if (u < length + 0.001) { // @todo: rb - need to use consistent tolerance
-         return fn(u);
-      }
-      u -= length;
-   }
+	// assume monotonic evaluation and store last evaluated segment
+    if (current_span_fn_ == nullptr || (u < current_span_start_ || current_span_end_ < u)) {
+       // there isn't a current span or u is outside the range of the current span
+		 // get a new "current span"
+        std::tie(current_span_start_,current_span_end_, current_span_fn_) = get_span(u);
+    }
+
+	 u -= current_span_start_; // make u relative to start of span
+	 return (*current_span_fn_)(u);
+}
+
+std::tuple<double, double, const std::function<Eigen::Matrix4d(double u)>*> ifcopenshell::geometry::taxonomy::piecewise_function::get_span(double u) const {
+	 // force u to be within bounds of the curve
+    double curve_length = length();
+    u = std::max(0.0, u);
+    u = std::min(u, curve_length);
+
+	double start = 0;
+    for (auto& [length, fn] : spans_) {
+		 auto tolerance = settings_ ? settings_->get<ifcopenshell::geometry::settings::Precision>().get() : 0.001;
+       if (u < length + tolerance) {
+           return {start, start+length, &fn} ;
+       }
+       start += length;
+       u -= length;
+    }
+
+    Logger::Error("taxonomy::piecewise_function::get_span span not found.");
+    return {0, 0, nullptr};
 }
 
 ifcopenshell::geometry::taxonomy::collection::ptr ifcopenshell::geometry::flatten(const taxonomy::collection::ptr& deep) {
@@ -512,7 +546,7 @@ const std::string& ifcopenshell::geometry::taxonomy::kind_to_string(kinds k) {
 	using namespace std::string_literals;
 
 	static std::string values[] = {
-		"matrix4"s, "point3"s, "direction3"s, "line"s, "circle"s, "ellipse"s, "bspline_curve"s, "offset_curve"s, "plane"s, "cylinder"s, "bspline_surface"s, "edge"s, "loop"s, "face"s, "shell"s, "solid"s, "loft"s, "extrusion"s, "revolve"s, "surface_curve_sweep"s, "node"s, "collection"s, "boolean_result"s, "piecewise_function"s, "colour"s, "style"s,
+		"matrix4"s, "point3"s, "direction3"s, "line"s, "circle"s, "ellipse"s, "bspline_curve"s, "offset_curve"s, "plane"s, "cylinder"s, "sphere"s, "bspline_surface"s, "edge"s, "loop"s, "face"s, "shell"s, "solid"s, "loft"s, "extrusion"s, "revolve"s, "surface_curve_sweep"s, "node"s, "collection"s, "boolean_result"s, "piecewise_function"s, "colour"s, "style"s,
 	};
 
 	return values[k];

src/ifcgeom/taxonomy.h

@@ -90,7 +90,7 @@ typedef item const* ptr;
 				topology_error(const char* const s) : std::runtime_error(s) {}
 			};
 
-			enum kinds { MATRIX4, POINT3, DIRECTION3, LINE, CIRCLE, ELLIPSE, BSPLINE_CURVE, OFFSET_CURVE, PLANE, CYLINDER, BSPLINE_SURFACE, EDGE, LOOP, FACE, SHELL, SOLID, LOFT, EXTRUSION, REVOLVE, SURFACE_CURVE_SWEEP, NODE, COLLECTION, BOOLEAN_RESULT, PIECEWISE_FUNCTION, COLOUR, STYLE };
+			enum kinds { MATRIX4, POINT3, DIRECTION3, LINE, CIRCLE, ELLIPSE, BSPLINE_CURVE, OFFSET_CURVE, PLANE, CYLINDER, SPHERE, BSPLINE_SURFACE, EDGE, LOOP, FACE, SHELL, SOLID, LOFT, EXTRUSION, REVOLVE, SURFACE_CURVE_SWEEP, NODE, COLLECTION, BOOLEAN_RESULT, PIECEWISE_FUNCTION, COLOUR, STYLE };
 
 			const std::string& kind_to_string(kinds k);
 
@@ -137,21 +137,32 @@ typedef item const* ptr;
 			};
 
 			struct piecewise_function : public implicit_item {
-				DECLARE_PTR(piecewise_function)
+            DECLARE_PTR(piecewise_function)
 
-				piecewise_function(const IfcUtil::IfcBaseInterface* instance = nullptr) : implicit_item(instance){};
-				piecewise_function(ifcopenshell::geometry::Settings* settings) : settings_(settings){};
+				using spans = std::vector<std::pair<double, std::function<Eigen::Matrix4d(double u)>>>;
+
+            piecewise_function(const spans& s, ifcopenshell::geometry::Settings* settings = nullptr, const IfcUtil::IfcBaseInterface* instance = nullptr) : 
+					implicit_item(instance), settings_(settings), spans_(s){};
+            piecewise_function(const std::vector<piecewise_function::ptr>& pwfs, ifcopenshell::geometry::Settings* settings = nullptr, const IfcUtil::IfcBaseInterface* instance = nullptr) : 
+					implicit_item(instance), settings_(settings)
+				{
+                for (auto& pwf : pwfs) {
+                    spans_.insert(spans_.end(), pwf->spans_.begin(), pwf->spans_.end());
+                }
+				};
             piecewise_function(piecewise_function&&) = default;
             piecewise_function(const piecewise_function&) = default;
 
-				ifcopenshell::geometry::Settings* settings_ = nullptr;
+				const ifcopenshell::geometry::Settings* settings_ = nullptr;
 
-				// length of span, function to evaluate span
-				std::vector<std::pair<double, std::function<Eigen::Matrix4d(double u)>>> spans;
+				bool is_empty() const { return spans_.empty(); }
 
 				double length() const {
-                    return std::accumulate(spans.begin(), spans.end(), 0.0, [](const auto& v,const auto& s) { return v + s.first; });
-                }
+					if (!length_.has_value()) {
+						length_ = std::accumulate(spans_.begin(), spans_.end(), 0.0, [](const auto& v, const auto& s) { return v + s.first; });
+					}
+               return *length_;
+            }
 
 				void print(std::ostream& o, int = 0) const {
 					o << "piecewise_function" << std::endl;
@@ -165,10 +176,34 @@ typedef item const* ptr;
 					return boost::hash<decltype(v)>{}(v);
 				}
 
-				virtual item::ptr evaluate() const;
-            item::ptr evaluate(double ustart, double uend,unsigned nsteps) const;
+				item::ptr evaluate() const override;
 
+            /// @brief evaluates the piecewise function between ustart and uend
+            /// @param ustart starting location - taken as 0.0 if before start
+            /// @param uend ending location - taken as length if beyond end
+            /// @param nsteps number of steps to evaluate
+            /// @return taxonomy::loop::ptr
+            item::ptr evaluate(double ustart, double uend, unsigned nsteps) const;
+
+            /// @brief evaluates the piecewise function between ustart and uend
+            /// @param ustart starting location - taken as 0.0 if before start
+            /// @param uend ending location - taken as length if beyond end
+            /// @param nsteps number of steps to evaluate
+            /// @return taxonomy::loop::ptr and vector of u values
+            std::pair<item::ptr, std::vector<double>> evaluate2(double ustart, double uend, unsigned nsteps) const;
+
+				/// @brief evaluates the piecewise function at u
+				/// @param u u is constrained to be between 0 and length
+				/// @return 4x4 placement matrix
 				Eigen::Matrix4d evaluate(double u) const;
+
+            private:
+               std::tuple<double, double, const std::function<Eigen::Matrix4d(double u)>*> get_span(double u) const;
+               spans spans_;
+               mutable double current_span_start_ = 0;
+				   mutable double current_span_end_ = 0;
+				   mutable const std::function<Eigen::Matrix4d(double u)>* current_span_fn_ = nullptr;
+               mutable boost::optional<double> length_;
 			};
 
 #ifdef TAXONOMY_USE_SHARED_PTR
@@ -875,6 +910,23 @@ typedef item const* ptr;
 				}
 			};
 
+			struct sphere : public surface {
+				DECLARE_PTR(sphere)
+
+				double radius;
+
+				virtual sphere* clone_() const { return new sphere(*this); }
+				virtual kinds kind() const { return SPHERE; }
+
+				void print(std::ostream& o, int) const {
+					o << "not implemented";
+				}
+				virtual size_t calc_hash() const {
+					auto v = std::make_tuple(static_cast<size_t>(SPHERE), matrix->hash_components());
+					return boost::hash<decltype(v)>{}(v);
+				}
+			};
+
 			struct bspline_surface : public surface {
 				DECLARE_PTR(bspline_surface)
 
@@ -1037,9 +1089,9 @@ typedef item const* ptr;
 			};
 
 			namespace impl {
-				typedef std::tuple<matrix4, point3, direction3, line, circle, ellipse, bspline_curve, offset_curve, plane, cylinder, bspline_surface, edge, loop, face, shell, solid, loft, extrusion, revolve, surface_curve_sweep, node, collection, boolean_result, piecewise_function> KindsTuple;
+				typedef std::tuple<matrix4, point3, direction3, line, circle, ellipse, bspline_curve, offset_curve, plane, cylinder, sphere, bspline_surface, edge, loop, face, shell, solid, loft, extrusion, revolve, surface_curve_sweep, node, collection, boolean_result, piecewise_function> KindsTuple;
 				typedef std::tuple<line, circle, ellipse, bspline_curve, offset_curve, loop, edge> CurvesTuple;
-				typedef std::tuple<plane, cylinder, bspline_surface> SurfacesTuple;
+				typedef std::tuple<plane, cylinder, sphere, bspline_surface> SurfacesTuple;
 			}
 
 			struct type_by_kind {
@@ -1139,7 +1191,8 @@ typedef item const* ptr;
                         if (loop->pwf.is_initialized()) {
                             pwf_ = loop->pwf;
                         } else {
-                            pwf_ = taxonomy::make<taxonomy::piecewise_function>();
+                            taxonomy::piecewise_function::spans spans;
+                            spans.reserve(loop->children.size());
                             for (auto& edge : loop->children) {
                                 // the edge could be an arc or trimmed circle in the case of IfcIndexPolyCurve - support for this isn't implemented yet
                                 if (edge->basis) {
@@ -1157,8 +1210,9 @@ typedef item const* ptr;
                                     axis = refDirection.cross(Y).normalized();
                                     return taxonomy::make<taxonomy::matrix4>(o, axis, refDirection)->components();
                                 };
-                                (*pwf_)->spans.emplace_back(l, fn);
+                                spans.emplace_back(l, fn);
                             }
+                            pwf_ = taxonomy::make<taxonomy::piecewise_function>(spans);
                             loop->pwf = pwf_;
                         }
                     }

src/ifcopenshell-python/docs/ifccsv.rst

@@ -153,7 +153,7 @@ interface to access the IfcOpenShell utilities.
 
 1. Install the BlenderBIM Add-on by following the `BlenderBIM Add-on
    installation documentation
-   <https://blenderbim.org/docs/users/installation.html>`_.
+   <https://docs.blenderbim.org/users/installation.html>`_.
 
 2. Launch Blender. Change to the **Scene Properties** tab in the **Properties
    Panel**. Scroll down to the **IFC Collaboration > IFC CSV Import / Export**

src/ifcopenshell-python/docs/ifcdiff.rst

@@ -88,7 +88,7 @@ interface to access the IfcOpenShell utilities.
 
 1. Install the BlenderBIM Add-on by following the `BlenderBIM Add-on
    installation documentation
-   <https://blenderbim.org/docs/users/installation.html>`_.
+   <https://docs.blenderbim.org/users/installation.html>`_.
 
 2. Launch Blender. Change to the **Scene Properties** tab in the **Properties
    Panel**. Scroll down to the **IFC Quality Control > IFC Diff** panel.

src/ifcopenshell-python/docs/ifcopenshell-python/installation.rst

@@ -227,7 +227,7 @@ The BlenderBIM Add-on is available either as a stable build or a daily build.
 
 1. Install the BlenderBIM Add-on by following the `BlenderBIM Add-on
    installation documentation
-   <https://blenderbim.org/docs/users/installation.html>`_.
+   <https://docs.blenderbim.org/users/installation.html>`_.
 
 2. Launch Blender. On the top left of the Viewport panel, click the **Editor
    Type** icon to change the viewport into a **Python Console**.
@@ -261,7 +261,7 @@ and run your script using the **Text > Run Script** menu or by clicking on the
    Blender.  This can help when learning how to write scripts as you can double
    check the results of your scripts with what you see in the graphical
    interface. `Read more
-   <https://blenderbim.org/docs/users/exploring_an_ifc_model.html>`_.
+   <https://docs.blenderbim.org/users/exploring_an_ifc_model.html>`_.
 
 From source with precompiled binaries
 -------------------------------------

src/ifcopenshell-python/docs/ifcsverchok/installation.rst

@@ -12,7 +12,7 @@ Packaged installation
 
 IfcSverchok is packaged like a regular Blender add-on, so installation is the
 same as any other Blender add-on. `Download IfcSverchok here
-<https://blenderbim.org/builds/ifcsverchok-230823.zip>`__.
+<https://github.com/IfcOpenShell/IfcOpenShell/releases/download/ifcsverchok-240417/ifcsverchok-240417.zip>`__.
 
 Like all Blender add-ons, they can be installed using ``Edit > Preferences >
 Addons > Install > Choose Downloaded ZIP > Enable Add-on Checkbox``. You can

src/ifcopenshell-python/ifcopenshell/__init__.py

@@ -39,6 +39,7 @@ import sys
 import tempfile
 import zipfile
 from pathlib import Path
+from typing import Optional
 
 import ifcopenshell.util.file
 
@@ -70,7 +71,7 @@ except Exception as e:
 
 from . import guid
 from .file import file
-from .entity_instance import entity_instance, register_schema_attributes
+from .entity_instance import entity_instance
 from .sql import sqlite, sqlite_entity
 try:
     from .stream import stream, stream_entity
@@ -170,7 +171,7 @@ def create_entity(type, schema="IFC4", *args, **kwargs):
         model = ifcopenshell.file()
         model.add(person) # #1=IfcPerson($,$,$,$,$,$,$,$)
     """
-    e = entity_instance((schema, type))
+    e = ifcopenshell_wrapper.make_instance(schema, type)
     attrs = list(enumerate(args)) + [(e.wrapped_data.get_argument_index(name), arg) for name, arg in kwargs.items()]
     for idx, arg in attrs:
         e[idx] = arg
@@ -194,15 +195,16 @@ def register_schema(schema):
     schema.schema.this.disown()
     schema.disown()
     ifcopenshell_wrapper.register_schema(schema.schema)
-    register_schema_attributes(schema.schema)
 
 
-def schema_by_name(schema=None, schema_version=None):
+def schema_by_name(
+    schema: Optional[str] = None, schema_version: Optional[tuple[int, ...]] = None
+) -> ifcopenshell_wrapper.schema_definition:
     """Returns an object allowing you to query the IFC schema itself
 
     :param schema: Which IFC schema to use, chosen from "IFC2X3", "IFC4",
         or "IFC4X3". These refer to the ISO approved versions of IFC.
-    :type schema: string
+    :type schema: string, optional
     :param schema_version: If you want to specify an exact version of IFC
         that may not be an ISO approved version, use this argument instead
         of ``schema``. IFC versions on technical.buildingsmart.org are
@@ -211,13 +213,15 @@ def schema_by_name(schema=None, schema_version=None):
         ADD2 TC1, which is the official version approved by ISO when people
         refer to "IFC4". Generally you should not use this argument unless
         you are testing non-ISO IFC releases.
-    :type schema_version: tuple[int]
+    :type schema_version: tuple[int, ...], optional
+    :return: Schema definition object.
+    :rtype: ifocpenshell_wrapper.schema_definition
     """
     if schema_version:
         prefixes = ("IFC", "X", "_ADD", "_TC")
         schema = "".join("".join(map(str, t)) if t[1] else "" for t in zip(prefixes, schema_version))
     else:
-        schema = {"IFC4X3": "IFC4X3_ADD1"}.get(schema, schema)
+        schema = {"IFC4X3": "IFC4X3_ADD2"}.get(schema, schema)
     return ifcopenshell_wrapper.schema_by_name(schema)
 
 

src/ifcopenshell-python/ifcopenshell/api/__init__.py

@@ -87,6 +87,36 @@ ARGUMENTS_DEPRECATION = {
     "material.unassign_material": partial(
         batching_argument_deprecation, prev_argument="product", new_argument="products"
     ),
+    "classification.add_reference": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "classification.remove_reference": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "library.assign_reference": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "library.unassign_reference": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "document.assign_document": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "document.unassign_document": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "spatial.reference_structure": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "spatial.dereference_structure": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "constraint.assign_constraint": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
+    "constraint.unassign_constraint": partial(
+        batching_argument_deprecation, prev_argument="product", new_argument="products"
+    ),
 }
 
 

src/ifcopenshell-python/ifcopenshell/api/attribute/edit_attributes.py

@@ -64,7 +64,8 @@ class Usecase:
                     self.settings["product"].PredefinedType = "USERDEFINED"
             elif hasattr(self.settings["product"], "ObjectType"):
                 relating_type = ifcopenshell.util.element.get_type(self.settings["product"])
-                if relating_type and relating_type.PredefinedType != "NOTDEFINED":
+                # Allow for None due to https://github.com/buildingSMART/IFC4.3.x-development/issues/818
+                if relating_type and relating_type.PredefinedType not in ("NOTDEFINED", None):
                     self.settings["product"].ObjectType = None
                     self.settings["product"].PredefinedType = None
                 elif (

src/ifcopenshell-python/ifcopenshell/api/classification/add_classification.py

@@ -19,10 +19,11 @@
 import ifcopenshell
 import ifcopenshell.util.schema
 import ifcopenshell.util.date
+from typing import Union
 
 
 class Usecase:
-    def __init__(self, file, classification=None):
+    def __init__(self, file: ifcopenshell.file, classification: Union[str, ifcopenshell.entity_instance]):
         """Adds a new classification system to the project
 
         External classification systems such as Uniclass or Omniclass are
@@ -81,7 +82,7 @@ class Usecase:
             "classification": classification,
         }
 
-    def execute(self):
+    def execute(self) -> ifcopenshell.entity_instance:
         if isinstance(self.settings["classification"], str):
             classification = self.file.createIfcClassification(Name=self.settings["classification"])
             self.relate_to_project(classification)

src/ifcopenshell-python/ifcopenshell/api/classification/add_reference.py

@@ -17,12 +17,24 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api
+import ifcopenshell.util.element
 import ifcopenshell.util.schema
+from typing import Optional, Union
 
 
 class Usecase:
-    def __init__(self, file, product=None, reference=None, identification=None, name=None, classification=None, is_lightweight=True):
-        """Adds a new classification reference and assigns it to a product
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        products: list[ifcopenshell.entity_instance],
+        reference: Optional[ifcopenshell.entity_instance] = None,
+        identification: Optional[str] = None,
+        name: Optional[str] = None,
+        classification: Optional[ifcopenshell.entity_instance] = None,
+        is_lightweight=True,
+    ):
+        """Adds a new classification reference and assigns it to the list of products
 
         A classification reference is a single entry such as "Pr_12_23_34" that
         is part of an external classification system (such as Uniclass or
@@ -33,7 +45,7 @@ class Usecase:
         resources such as profiles, documents, libraries, and so on.
 
         Classification references can be added in two ways. Option 1) specify  a
-        custom arbitrary reference, where you have the manually specify the
+        custom arbitrary reference, where you have to manually specify the
         identification (e.g. "Pr_12_23_45") and name (e.g. "Door Products").
         Option 2) add a reference from an IFC classification library. The latter
         is preferred if you are using a common classification system such as
@@ -52,13 +64,13 @@ class Usecase:
         assigned to both the type and an occurrence, then the assignment at the
         occurrence will override the type classification.
 
-        :param product: The IFC object, property, or resource you want to
+        :param product: The list of IFC objects, properties, or resources you want to
             associate the classification reference to.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :type product: list[ifcopenshell.entity_instance.entity_instance]
         :param reference: The classification reference entity taken from an
             IFC classification library. If you supply this parameter, you will
             use option 2.
-        :type product: ifcopenshell.entity_instance.entity_instance, optional
+        :type reference: ifcopenshell.entity_instance.entity_instance, optional
         :param identification: If you choose option 1 and do not specify a
             reference, you may manually specify an identification code. The code
             is typically a short identifier and may have punctuation to separate
@@ -70,7 +82,7 @@ class Usecase:
         :param classification: The IfcClassification entity in your IFC model
             (not the library, if you are doing option 2) that the reference is
             part of.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :type classification: ifcopenshell.entity_instance.entity_instance
         :param is_lightweight: If you are doing option 2, choose whether or not
             to only add that particular reference (lighweight) or also add all
             of its parent references in the classification hierarchy (not
@@ -81,8 +93,12 @@ class Usecase:
             is generally unnecessary. Using lightweight classifications are
             recommended and is the default.
         :type is_lightweight: bool, optional
+
+        :raises TypeError: If file is IFC2X3 and `products` has non-IfcRoot elements.
+
         :return: The newly added IfcClassificationReference
-        :rtype: ifcopenshell.entity_instance.entity_instance
+            or `None` if `products` was empty list.
+        :rtype: Union[ifcopenshell.entity_instance.entity_instance, None]
 
         Example:
 
@@ -93,7 +109,7 @@ class Usecase:
             classification = ifcopenshell.api.run("classification.add_classification",
                 model, classification="MyCustomClassification")
             ifcopenshell.api.run("classification.add_reference", model,
-                product=wall_type, classification=classification,
+                products=[wall_type], classification=classification,
                 identification="W_01", name="Interior Walls")
 
             # Option 2: adding a popular classification from a library
@@ -104,12 +120,12 @@ class Usecase:
             reference = [r for r in library.by_type("IfcClassificationReference")
                 if r.Identification == "XYZ"][0]
             ifcopenshell.api.run("classification.add_reference", model,
-                product=wall_type, classification=classification,
+                products=[wall_type], classification=classification,
                 reference=reference)
         """
         self.file = file
         self.settings = {
-            "product": product,
+            "products": products,
             "reference": reference,
             "identification": identification,
             "name": name,
@@ -117,8 +133,27 @@ class Usecase:
             "is_lightweight": is_lightweight,
         }
 
-    def execute(self):
-        self.is_rooted = self.settings["product"].is_a("IfcRoot")
+    def execute(self) -> Union[ifcopenshell.entity_instance, None]:
+        if not self.settings["products"]:
+            return
+
+        if self.settings["reference"]:
+            referenced = ifcopenshell.util.element.get_referenced_elements(self.settings["reference"])
+            if set(self.settings["products"]).issubset(referenced):
+                # nothing to do, all elements already have this reference assigned
+                return self.settings["reference"]
+
+        self.rooted_products: set[ifcopenshell.entity_instance] = set()
+        self.non_rooted_products: set[ifcopenshell.entity_instance] = set()
+        for product in self.settings["products"]:
+            if product.is_a("IfcRoot"):
+                self.rooted_products.add(product)
+            else:
+                self.non_rooted_products.add(product)
+
+        if self.non_rooted_products and self.file.schema == "IFC2X3":
+            raise TypeError(f"Cannot add reference to non-IfcRoot element in IFC2X3: {self.non_rooted_products}.")
+
         if self.settings["reference"]:
             return self.add_from_library()
         return self.add_from_identification()
@@ -134,14 +169,10 @@ class Usecase:
             else:
                 reference.Identification = self.settings["identification"]
 
-        relationship = self.get_existing_relationship(reference)
-        if relationship:
-            self.add_to_existing_relationship(relationship)
-        else:
-            self.add_new_relationship(reference)
+        self.update_relationships(reference)
         return reference
 
-    def add_from_library(self):
+    def add_from_library(self) -> ifcopenshell.entity_instance:
         if hasattr(self.settings["reference"], "ItemReference"):
             identification = self.settings["reference"].ItemReference  # IFC2X3
         else:
@@ -155,8 +186,9 @@ class Usecase:
                 old_referenced_source = self.settings["reference"].ReferencedSource
                 self.settings["reference"].ReferencedSource = None
             else:
+                classification_name = self.settings["classification"].Name
                 existing_classification = [
-                    c for c in self.file.by_type("IfcClassification") if c.Name == self.settings["classification"].Name
+                    c for c in self.file.by_type("IfcClassification") if c.Name == classification_name
                 ]
 
             reference = migrator.migrate(self.settings["reference"], self.file)
@@ -174,15 +206,10 @@ class Usecase:
                 for element in to_delete:
                     self.file.remove(element)
 
-        relationship = self.get_existing_relationship(reference)
-        if relationship:
-            self.add_to_existing_relationship(relationship)
-        else:
-            self.add_new_relationship(reference)
-
+        self.update_relationships(reference)
         return reference
 
-    def get_existing_reference(self, identification):
+    def get_existing_reference(self, identification: Optional[str] = None) -> Union[ifcopenshell.entity_instance, None]:
         for reference in self.file.by_type("IfcClassificationReference"):
             if self.file.schema == "IFC2X3":
                 if reference.ItemReference == identification:
@@ -191,39 +218,39 @@ class Usecase:
                 if reference.Identification == identification:
                     return reference
 
-    def add_new_relationship(self, reference):
-        if self.is_rooted:
-            self.file.create_entity(
-                "IfcRelAssociatesClassification",
-                GlobalId=ifcopenshell.guid.new(),
-                RelatedObjects=[self.settings["product"]],
-                RelatingClassification=reference,
-            )
-        else:
-            self.file.create_entity(
-                "IfcExternalReferenceRelationship",
-                RelatingReference=reference,
-                RelatedResourceObjects=[self.settings["product"]],
-            )
-
-    def add_to_existing_relationship(self, rel):
-        if self.is_rooted:
-            related_objects = set(rel.RelatedObjects)
-            related_objects.add(self.settings["product"])
-            rel.RelatedObjects = list(related_objects)
-        else:
-            related_objects = set(rel.RelatedResourceObjects)
-            related_objects.add(self.settings["product"])
-            rel.RelatedResourceObjects = list(related_objects)
-
-    def get_existing_relationship(self, reference):
-        if self.is_rooted:
+    def update_relationships(self, reference: ifcopenshell.entity_instance) -> None:
+        root_rel, non_root_rel = None, None
+        if self.rooted_products:
             if self.file.schema == "IFC2X3":
                 for rel in self.file.by_type("IfcRelAssociatesClassification"):
                     if rel.RelatingClassification == reference:
-                        return rel
-            elif reference.ClassificationRefForObjects:
-                return reference.ClassificationRefForObjects[0]
-        elif self.file.schema != "IFC2X3":
-            if reference.ExternalReferenceForResources:
-                return reference.ExternalReferenceForResources[0]
+                        root_rel = rel
+                        break
+            else:
+                root_rel = next(iter(reference.ClassificationRefForObjects), None)
+
+            if root_rel:
+                related_objects = set(root_rel.RelatedObjects) | self.rooted_products
+                root_rel.RelatedObjects = list(related_objects)
+                ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": root_rel})
+            else:
+                self.file.create_entity(
+                    "IfcRelAssociatesClassification",
+                    OwnerHistory=ifcopenshell.api.run("owner.create_owner_history", self.file),
+                    GlobalId=ifcopenshell.guid.new(),
+                    RelatedObjects=list(self.rooted_products),
+                    RelatingClassification=reference,
+                )
+
+        if self.non_rooted_products:
+            # NOTE: Only Ifc4+. Ifc2x3 is already handled by raising TypeError
+            non_root_rel = next(iter(reference.ExternalReferenceForResources), None)
+            if non_root_rel:
+                related_objects = set(non_root_rel.RelatedResourceObjects) | self.non_rooted_products
+                non_root_rel.RelatedResourceObjects = list(related_objects)
+            else:
+                self.file.create_entity(
+                    "IfcExternalReferenceRelationship",
+                    RelatingReference=reference,
+                    RelatedResourceObjects=list(self.non_rooted_products),
+                )

src/ifcopenshell-python/ifcopenshell/api/classification/remove_reference.py

@@ -17,12 +17,18 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api
 import ifcopenshell.util.element
 
 
 class Usecase:
-    def __init__(self, file, reference=None, product=None):
-        """Removes a classification reference from a product
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        reference: ifcopenshell.entity_instance,
+        products: list[ifcopenshell.entity_instance],
+    ):
+        """Removes a classification reference from the list of products
 
         If the classification reference is no longer associated to any products,
         the classification reference itself is also removed.
@@ -30,9 +36,12 @@ class Usecase:
         :param reference: The IfcClassificationReference entity of the
             relationship you want to remove.
         :type reference: ifcopenshell.entity_instance.entity_instance
-        :param product: The object entity of the relationship you want to
+        :param product: The list fo object entities of the relationship you want to
             remove.
-        :type reference: ifcopenshell.entity_instance.entity_instance
+        :type product: list[ifcopenshell.entity_instance.entity_instance]
+
+        :raises TypeError: If file is IFC2X3 and `products` has non-IfcRoot elements.
+
         :return: None
         :rtype: None
 
@@ -44,42 +53,75 @@ class Usecase:
             classification = ifcopenshell.api.run("classification.add_classification",
                 model, classification="MyCustomClassification")
             reference = ifcopenshell.api.run("classification.add_reference", model,
-                product=wall_type, classification=classification,
+                products=[wall_type], classification=classification,
                 identification="W_01", name="Interior Walls")
             ifcopenshell.api.run("classification.remove_reference", model,
-                reference=reference, product=wall_type)
+                reference=reference, products=[wall_type])
         """
         self.file = file
-        self.settings = {"reference": reference, "product": product}
+        self.settings = {"reference": reference, "products": products}
 
-    def execute(self):
-        if self.settings["product"].is_a("IfcRoot"):
-            for rel in self.file.by_type("IfcRelAssociatesClassification"):
-                if rel.RelatingClassification == self.settings["reference"] and rel.RelatedObjects:
-                    if self.settings["product"] in rel.RelatedObjects:
-                        related_objects = list(rel.RelatedObjects)
-                        related_objects.remove(self.settings["product"])
-                        if len(related_objects):
-                            rel.RelatedObjects = related_objects
-                        else:
-                            history = rel.OwnerHistory
-                            self.file.remove(rel)
-                            if history:
-                                ifcopenshell.util.element.remove_deep2(self.file, history)
-        else:
-            for rel in self.file.by_type("IfcExternalReferenceRelationship"):
-                if rel.RelatingReference == self.settings["reference"] and rel.RelatedResourceObjects:
-                    if self.settings["product"] in rel.RelatedResourceObjects:
-                        related_objects = list(rel.RelatedResourceObjects)
-                        related_objects.remove(self.settings["product"])
-                        if len(related_objects):
-                            rel.RelatedResourceObjects = related_objects
-                        else:
-                            self.file.remove(rel)
+    def execute(self) -> None:
+        is_ifc2x3 = self.file.schema == "IFC2X3"
+        products = set(self.settings["products"])
+        referenced = ifcopenshell.util.element.get_referenced_elements(self.settings["reference"])
+        products -= products.difference(referenced)
+
+        # all products are already unassigned from a reference
+        if not products:
+            return
+
+        rooted_products: set[ifcopenshell.entity_instance] = set()
+        non_rooted_products: set[ifcopenshell.entity_instance] = set()
+        for product in self.settings["products"]:
+            if product.is_a("IfcRoot"):
+                rooted_products.add(product)
+            else:
+                non_rooted_products.add(product)
+
+        if non_rooted_products and is_ifc2x3:
+            raise TypeError(f"Cannot add reference to non-IfcRoot element in IFC2X3: {non_rooted_products}.")
+
+        if rooted_products:
+            reference_rels: set[ifcopenshell.entity_instance] = set()
+            for product in rooted_products:
+                reference_rels.update(product.HasAssociations)
+
+            reference_rels = {
+                rel
+                for rel in reference_rels
+                if rel.is_a("IfcRelAssociatesClassification")
+                and rel.RelatingClassification == self.settings["reference"]
+            }
+
+            for rel in reference_rels:
+                related_objects = set(rel.RelatedObjects) - rooted_products
+                if related_objects:
+                    rel.RelatedObjects = list(related_objects)
+                    ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
+                else:
+                    history = rel.OwnerHistory
+                    self.file.remove(rel)
+                    if history:
+                        ifcopenshell.util.element.remove_deep2(self.file, history)
+
+        if non_rooted_products:
+            reference_rels: set[ifcopenshell.entity_instance] = set()
+            for product in non_rooted_products:
+                rels = getattr(product, "HasExternalReferences", None)
+                if rels is None:
+                    rels = getattr(product, "HasExternalReference", [])
+                reference_rels.update(rels)
+
+            reference_rels = {rel for rel in reference_rels if rel.RelatingReference == self.settings["reference"]}
+            for rel in reference_rels:
+                related_objects = set(rel.RelatedResourceObjects) - non_rooted_products
+                if related_objects:
+                    rel.RelatedResourceObjects = list(related_objects)
+                else:
+                    self.file.remove(rel)
 
         # TODO: we only handle lightweight classifications here
-        if (
-            not self.settings["reference"].ClassificationRefForObjects
-            and not self.settings["reference"].ExternalReferenceForResources
-        ):
+        referenced_elements = ifcopenshell.util.element.get_referenced_elements(self.settings["reference"])
+        if not referenced_elements:
             self.file.remove(self.settings["reference"])

src/ifcopenshell-python/ifcopenshell/api/constraint/assign_constraint.py

@@ -17,11 +17,18 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api
+from typing import Union
 
 
 class Usecase:
-    def __init__(self, file, product=None, constraint=None):
-        """Assigns a constraint to a product
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        products: list[ifcopenshell.entity_instance],
+        constraint: ifcopenshell.entity_instance,
+    ):
+        """Assigns a constraint to a list of products
 
         This assigns a relationship between a product and a constraint, so that
         when a product's properties and quantities do not match the requirements
@@ -31,36 +38,58 @@ class Usecase:
         constraints are inherited from the type. This way, it is not necessary
         to create lots of constraint assignments.
 
-        :param product: The product the constraint applies to. This is anything
+        :param products: The list of products the constraint applies to. This is anything
             which can have properties or quantities.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :type products: list[ifcopenshell.entity_instance.entity_instance]
         :param constraint: The IfcObjective constraint
         :type constraint: ifcopenshell.entity_instance.entity_instance
         :return: The new or updated IfcRelAssociatesConstraint relationship
+            or `None` if `products` was an empty list.
         :rtype: ifcopenshell.entity_instance.entity_instance
         """
         self.file = file
         self.settings = {
-            "product": product,
+            "products": products,
             "constraint": constraint,
         }
 
-    def execute(self):
-        rel = self.get_constraint_rel()
-        related_objects = set(rel.RelatedObjects) if rel.RelatedObjects else set()
-        related_objects.add(self.settings["product"])
-        rel.RelatedObjects = list(related_objects)
-        return rel
+    def execute(self) -> Union[ifcopenshell.entity_instance, None]:
+        products = set(self.settings["products"])
+        if not products:
+            return
+
+        self.constraint = self.settings["constraint"]
+
+        rels = self.get_constraint_rels()
+        related_objects = set()
+        for rel in rels:
+            related_objects.update(rel.RelatedObjects)
+
+        products_to_assign = products - related_objects
+        if not products_to_assign:
+            return rels[0]
+
+        rel = next(iter(rels), None)
+
+        if rel:
+            related_objects = set(rel.RelatedObjects) | products_to_assign
+            rel.RelatedObjects = list(related_objects)
+            ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
+            return rel
 
-    def get_constraint_rel(self):
-        for rel in self.file.by_type("IfcRelAssociatesConstraint"):
-            if rel.RelatingConstraint == self.settings["constraint"]:
-                return rel
         return self.file.create_entity(
             "IfcRelAssociatesConstraint",
             **{
                 "GlobalId": ifcopenshell.guid.new(),
-                # TODO: owner history
-                "RelatingConstraint": self.settings["constraint"],
+                "OwnerHistory": ifcopenshell.api.run("owner.create_owner_history", self.file),
+                "RelatingConstraint": self.constraint,
+                "RelatedObjects": list(products_to_assign),
             }
         )
+
+    def get_constraint_rels(self) -> list[ifcopenshell.entity_instance]:
+        rels = []
+        for rel in self.file.get_inverse(self.constraint):
+            if rel.is_a("IfcRelAssociatesConstraint"):
+                rels.append(rel)
+        return rels

src/ifcopenshell-python/ifcopenshell/api/constraint/unassign_constraint.py

@@ -17,18 +17,24 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api
 import ifcopenshell.util.element
 
 
 class Usecase:
-    def __init__(self, file, product=None, constraint=None):
-        """Unassigns a constraint to a product
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        products: list[ifcopenshell.entity_instance],
+        constraint: ifcopenshell.entity_instance,
+    ):
+        """Unassigns a constraint from a list of products
 
         The constraint will not be deleted and is available to be assigned to
         other products.
 
-        :param product: The product the constraint applies to.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :param products: The list of products the constraint applies to.
+        :type products: list[ifcopenshell.entity_instance.entity_instance]
         :param constraint: The IfcObjective constraint
         :type constraint: ifcopenshell.entity_instance.entity_instance
         :return: None
@@ -36,14 +42,42 @@ class Usecase:
         """
         self.file = file
         self.settings = {
-            "product": product,
+            "products": products,
             "constraint": constraint,
         }
 
     def execute(self):
-        for rel in self.settings["product"].HasAssociations:
-            if rel.is_a("IfcRelAssociatesConstraint") and rel.RelatingConstraint == self.settings["constraint"]:
-                history = rel.OwnerHistory
-                self.file.remove(rel)
-                if history:
-                    ifcopenshell.util.element.remove_deep2(self.file, history)
+        products = set(self.settings["products"])
+        if not products:
+            return
+
+        self.constraint = self.settings["constraint"]
+        rels = self.get_constraint_rels()
+        related_objects = set()
+        for rel in rels:
+            related_objects.update(rel.RelatedObjects)
+
+        if not related_objects.intersection(products):
+            return
+
+        for rel in rels:
+            related_objects = set(rel.RelatedObjects)
+            if not related_objects.intersection(products):
+                continue
+            related_objects -= products
+            if related_objects:
+                rel.RelatedObjects = list(related_objects)
+                ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
+                continue
+
+            history = rel.OwnerHistory
+            self.file.remove(rel)
+            if history:
+                ifcopenshell.util.element.remove_deep2(self.file, history)
+
+    def get_constraint_rels(self) -> list[ifcopenshell.entity_instance]:
+        rels = []
+        for rel in self.file.get_inverse(self.constraint):
+            if rel.is_a("IfcRelAssociatesConstraint"):
+                rels.append(rel)
+        return rels

src/ifcopenshell-python/ifcopenshell/api/document/add_reference.py

@@ -69,10 +69,12 @@ class Usecase:
 
     def execute(self) -> ifcopenshell.entity_instance:
         if self.file.schema == "IFC2X3":
-            reference = self.file.create_entity("IfcDocumentReference")
+            reference = self.file.create_entity("IfcDocumentReference", ItemReference="X")
             if self.settings["information"]:
                 references = list(self.settings["information"].DocumentReferences or [])
                 references.append(reference)
                 self.settings["information"].DocumentReferences = references
             return reference
-        return self.file.create_entity("IfcDocumentReference", ReferencedDocument=self.settings["information"])
+        return self.file.create_entity(
+            "IfcDocumentReference", ReferencedDocument=self.settings["information"], Identification="X"
+        )

src/ifcopenshell-python/ifcopenshell/api/document/assign_document.py

@@ -17,11 +17,19 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api
+import ifcopenshell.util.element
+from typing import Union
 
 
 class Usecase:
-    def __init__(self, file, product=None, document=None):
-        """Assigns a document to a product
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        products: list[ifcopenshell.entity_instance],
+        document: ifcopenshell.entity_instance,
+    ):
+        """Assigns a document to a list of products
 
         An object may be assigned to zero, one, or multiple documents. Almost
         any object or property may be assigned to a document, though typically
@@ -32,14 +40,16 @@ class Usecase:
         consistent with other external relationships (such as classification
         systems or libraries).
 
-        :param product: The object to associate the document to. This could be
+        :param product: The list of objects to associate the document to. This could be
             almost any sensible object in IFC.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :type product: list[ifcopenshell.entity_instance.entity_instance]
         :param document: The IfcDocumentReference to associate to, or
             alternatively an IfcDocumentInformation, though this is not
             recommended.
         :type document: ifcopenshell.entity_instance.entity_instance
         :return: The IfcRelAssociatesDocument relationship
+            or `None` if `products` was an empty list or all products were
+            already assigned to the `document`.
         :rtype: ifcopenshell.entity_instance.entity_instance
 
         Example:
@@ -54,42 +64,51 @@ class Usecase:
             reference = ifcopenshell.api.run("document.add_reference", model, information=document)
 
             # Let's imagine storey represents an IfcBuildingStorey for the ground floor
-            ifcopenshell.api.run("document.assign_document", model, product=storey, document=reference)
+            ifcopenshell.api.run("document.assign_document", model, products=[storey], document=reference)
         """
         self.file = file
         self.settings = {
-            "product": product,
+            "products": products,
             "document": document,
         }
 
-    def execute(self):
-        rel = self.get_document_rel()
-        related_objects = set(rel.RelatedObjects) if rel.RelatedObjects else set()
-        related_objects.add(self.settings["product"])
-        rel.RelatedObjects = list(related_objects)
+    def execute(self) -> Union[ifcopenshell.entity_instance, None]:
+        # TODO: do we need to support non-ifcroot elements like we do in classification.add_reference?
+        # NOTE: reuses code from `library.assign_reference`
+
+        referenced_elements = ifcopenshell.util.element.get_referenced_elements(self.settings["document"])
+        products: set[ifcopenshell.entity_instance] = set(self.settings["products"])
+        products = products - referenced_elements
+
+        if not products:
+            return
 
-    def get_document_rel(self):
         if self.file.schema == "IFC2X3":
-            for rel in self.file.by_type("IfcRelAssociatesDocument"):
-                if rel.RelatingDocument == self.settings["document"]:
-                    return rel
+            rel = next(
+                (
+                    r
+                    for r in self.file.by_type("IfcRelAssociatesDocument")
+                    if r.RelatingDocument == self.settings["document"]
+                ),
+                None,
+            )
         else:
-            if (
-                hasattr(self.settings["document"], "DocumentRefForObjects")
-                and self.settings["document"].DocumentRefForObjects
-            ):
-                return self.settings["document"].DocumentRefForObjects[0]
-            elif (
-                hasattr(self.settings["document"], "DocumentInfoForObjects")
-                and self.settings["document"].DocumentInfoForObjects
-            ):
-                return self.settings["document"].DocumentInfoForObjects[0]
+            ifc_class = self.settings["document"].is_a()
+            if ifc_class == "IfcDocumentReference":
+                rel = next(iter(self.settings["document"].DocumentRefForObjects), None)
+            elif ifc_class == "IfcDocumentInformation":
+                rel = next(iter(self.settings["document"].DocumentInfoForObjects), None)
 
-        return self.file.create_entity(
-            "IfcRelAssociatesDocument",
-            **{
-                "GlobalId": ifcopenshell.guid.new(),
-                "OwnerHistory": ifcopenshell.api.run("owner.create_owner_history", self.file),
-                "RelatingDocument": self.settings["document"],
-            }
-        )
+        if not rel:
+            return self.file.create_entity(
+                "IfcRelAssociatesDocument",
+                GlobalId=ifcopenshell.guid.new(),
+                OwnerHistory=ifcopenshell.api.run("owner.create_owner_history", self.file),
+                RelatedObjects=list(products),
+                RelatingDocument=self.settings["document"],
+            )
+
+        related_objects = set(rel.RelatedObjects) | products
+        rel.RelatedObjects = list(related_objects)
+        ifcopenshell.api.run("owner.update_owner_history", self.file, element=rel)
+        return rel

src/ifcopenshell-python/ifcopenshell/api/document/unassign_document.py

@@ -17,16 +17,22 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api
 import ifcopenshell.util.element
 
 
 class Usecase:
-    def __init__(self, file, product=None, document=None):
-        """Unassigns a document and a product association
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        products: list[ifcopenshell.entity_instance],
+        document: ifcopenshell.entity_instance,
+    ):
+        """Unassigns a document and an association to the list of products
 
-        :param product: The object that the document reference or information is
+        :param product: The list of objects that the document reference or information is
             related to.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :type product: list[ifcopenshell.entity_instance.entity_instance]
         :param document: The IfcDocumentReference (typically) or in rare cases
             the IfcDocumentInformation that is associated with the product
         :type document: ifcopenshell.entity_instance.entity_instance
@@ -45,24 +51,39 @@ class Usecase:
             reference = ifcopenshell.api.run("document.add_reference", model, information=document)
 
             # Let's imagine storey represents an IfcBuildingStorey for the ground floor
-            ifcopenshell.api.run("document.assign_document", model, product=storey, document=reference)
+            ifcopenshell.api.run("document.assign_document", model, products=[storey], document=reference)
 
             # Now let's change our mind and remove the association
-            ifcopenshell.api.run("document.unassign_document", model, product=storey, document=reference)
+            ifcopenshell.api.run("document.unassign_document", model, products=[storey], document=reference)
         """
         self.file = file
         self.settings = {
-            "product": product,
+            "products": products,
             "document": document,
         }
 
     def execute(self):
-        for rel in self.settings["product"].HasAssociations:
-            if rel.is_a("IfcRelAssociatesDocument") and rel.RelatingDocument == self.settings["document"]:
-                if len(rel.RelatedObjects) == 1:
-                    history = rel.OwnerHistory
-                    self.file.remove(rel)
-                    if history:
-                        ifcopenshell.util.element.remove_deep2(self.file, history)
-                else:
-                    rel.RelatedObjects = [o for o in rel.RelatedObjects if o != self.settings["product"]]
+        # TODO: do we need to support non-ifcroot elements like we do in classification.add_reference?
+        # NOTE: reuses code from `library.un assign_reference`
+
+        reference_rels: set[ifcopenshell.entity_instance] = set()
+        products = set(self.settings["products"])
+        for product in products:
+            reference_rels.update(product.HasAssociations)
+
+        reference_rels = {
+            rel
+            for rel in reference_rels
+            if rel.is_a("IfcRelAssociatesDocument") and rel.RelatingDocument == self.settings["document"]
+        }
+
+        for rel in reference_rels:
+            related_objects = set(rel.RelatedObjects) - products
+            if related_objects:
+                rel.RelatedObjects = list(related_objects)
+                ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
+            else:
+                history = rel.OwnerHistory
+                self.file.remove(rel)
+                if history:
+                    ifcopenshell.util.element.remove_deep2(self.file, history)

src/ifcopenshell-python/ifcopenshell/api/georeference/edit_georeferencing.py

@@ -26,7 +26,7 @@ class Usecase:
         surveyor, and a third-party digital engineer with expertise in IFC to
         moderate. For more information, read the BlenderBIM Add-on documentation
         for Georeferencing:
-        https://blenderbim.org/docs/users/georeferencing.html
+        https://docs.blenderbim.org/users/georeferencing.html
 
         For more information about the attributes and data types of an
         IfcMapConversion, consult the IFC documentation.

src/ifcopenshell-python/ifcopenshell/api/library/assign_reference.py

@@ -17,23 +17,30 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api
+import ifcopenshell.util.element
+from typing import Union
 
 
 class Usecase:
-    def __init__(self, file, product=None, reference=None):
-        """Associates a product with a library reference
+    def __init__(
+        self, file: ifcopenshell.file, products: ifcopenshell.entity_instance, reference: ifcopenshell.entity_instance
+    ):
+        """Associates a list products with a library reference
 
         A product may be associated with zero, one, or many references across
         multiple libraries. See ifcopenshell.api.library.add_reference for more
         detail about how references work.
 
-        :param product: The IfcProduct you want to associate with the reference
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :param products: The list of IfcProducts you want to associate with the reference
+        :type products: list[ifcopenshell.entity_instance.entity_instance]
         :param reference: The IfcLibraryReference you want the product to be
             associated with.
         :type reference: ifcopenshell.entity_instance.entity_instance
         :return: The IfcRelAssociatesLibrary relationship entity
-        :rtype: ifcopenshell.entity_instance.entity_instance
+            or `None` if `products` was an empty list or all products were
+            already assigned to the `reference`.
+        :rtype: Union[ifcopenshell.entity_instance.entity_instance, None]
 
         Example:
 
@@ -51,40 +58,46 @@ class Usecase:
                 ifc_class="IfcUnitaryEquipment", predefined_type="AIRHANDLER")
 
             # And now assign the IFC model's AHU with its Brickschema counterpart
-            ifcopenshell.api.run("library.assign_reference", model, reference=reference, product=ahu)
+            ifcopenshell.api.run("library.assign_reference", model, reference=reference, products=[ahu])
         """
         self.file = file
         self.settings = {
-            "product": product,
+            "products": products,
             "reference": reference,
         }
 
-    def execute(self):
+    def execute(self) -> Union[ifcopenshell.entity_instance, None]:
+        # TODO: do we need to support non-ifcroot elements like we do in classification.add_reference?
+
+        referenced_elements = ifcopenshell.util.element.get_referenced_elements(self.settings["reference"])
+        products: set[ifcopenshell.entity_instance] = set(self.settings["products"])
+        products = products - referenced_elements
+
+        if not products:
+            return
+
         if self.file.schema == "IFC2X3":
-            rels = self.get_ifc2x3_rels()
+            rel = next(
+                (
+                    r
+                    for r in self.file.by_type("IfcRelAssociatesLibrary")
+                    if r.RelatingLibrary == self.settings["reference"]
+                ),
+                None,
+            )
         else:
-            rels = self.settings["reference"].LibraryRefForObjects
-        if not rels:
+            rel = next(iter(self.settings["reference"].LibraryRefForObjects), None)
+
+        if not rel:
             return self.file.create_entity(
                 "IfcRelAssociatesLibrary",
                 GlobalId=ifcopenshell.guid.new(),
                 OwnerHistory=ifcopenshell.api.run("owner.create_owner_history", self.file),
-                RelatedObjects=[self.settings["product"]],
+                RelatedObjects=list(products),
                 RelatingLibrary=self.settings["reference"],
             )
 
-        for rel in rels:
-            if self.settings["product"] in rel.RelatedObjects:
-                return rel
-
-        rel = rels[0]
-        related_objects = list(rel.RelatedObjects)
-        related_objects.append(self.settings["product"])
-        rel.RelatedObjects = related_objects
+        related_objects = set(rel.RelatedObjects) | products
+        rel.RelatedObjects = list(related_objects)
         ifcopenshell.api.run("owner.update_owner_history", self.file, element=rel)
         return rel
-
-    def get_ifc2x3_rels(self):
-        return [
-            r for r in self.file.by_type("IfcRelAssociatesLibrary") if r.RelatingLibrary == self.settings["reference"]
-        ]

src/ifcopenshell-python/ifcopenshell/api/library/unassign_reference.py

@@ -18,18 +18,24 @@
 
 import ifcopenshell
 import ifcopenshell.util.element
+import ifcopenshell.api
 
 
 class Usecase:
-    def __init__(self, file, reference=None, product=None):
-        """Unassigns a product from a reference
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        reference: ifcopenshell.entity_instance,
+        products: list[ifcopenshell.entity_instance],
+    ):
+        """Unassigns a product of products from a reference
 
         If the product isn't assigned to the reference, nothing will happen.
 
         :param reference: The IfcLibraryReference to unassign from
         :type reference: ifcopenshell.entity_instance.entity_instance
-        :param product: A IfcProduct element to unassign from the reference
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :param products: A list of IfcProduct elements to unassign from the reference
+        :type products: list[ifcopenshell.entity_instance.entity_instance]
         :return: None
         :rtype: None
 
@@ -49,27 +55,36 @@ class Usecase:
                 ifc_class="IfcUnitaryEquipment", predefined_type="AIRHANDLER")
 
             # And now assign the IFC model's AHU with its Brickschema counterpart
-            ifcopenshell.api.run("library.assign_reference", model, reference=reference, product=ahu)
+            ifcopenshell.api.run("library.assign_reference", model, reference=reference, products=[ahu])
 
             # Let's change our mind and unassign it.
-            ifcopenshell.api.run("library.unassign_reference", model, reference=reference, product=ahu)
+            ifcopenshell.api.run("library.unassign_reference", model, reference=reference, products=[ahu])
         """
 
         self.file = file
-        self.settings = {"reference": reference, "product": product}
+        self.settings = {"reference": reference, "products": products}
 
     def execute(self):
-        rels = self.settings["reference"].LibraryRefForObjects
-        if not rels:
-            return
-        for rel in rels:
-            if self.settings["product"] in rel.RelatedObjects:
-                if len(rel.RelatedObjects) == 1:
-                    history = rel.OwnerHistory
-                    self.file.remove(rel)
-                    if history:
-                        ifcopenshell.util.element.remove_deep2(self.file, history)
-                    continue
-                related_objects = list(rel.RelatedObjects)
-                related_objects.remove(self.settings["product"])
-                rel.RelatedObjects = related_objects
+        # TODO: do we need to support non-ifcroot elements like we do in classification.add_reference?
+
+        reference_rels: set[ifcopenshell.entity_instance] = set()
+        products = set(self.settings["products"])
+        for product in products:
+            reference_rels.update(product.HasAssociations)
+
+        reference_rels = {
+            rel
+            for rel in reference_rels
+            if rel.is_a("IfcRelAssociatesLibrary") and rel.RelatingLibrary == self.settings["reference"]
+        }
+
+        for rel in reference_rels:
+            related_objects = set(rel.RelatedObjects) - products
+            if related_objects:
+                rel.RelatedObjects = list(related_objects)
+                ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
+            else:
+                history = rel.OwnerHistory
+                self.file.remove(rel)
+                if history:
+                    ifcopenshell.util.element.remove_deep2(self.file, history)

src/ifcopenshell-python/ifcopenshell/api/owner/settings.py

@@ -38,7 +38,7 @@ def get_application(ifc: ifcopenshell.file) -> Union[ifcopenshell.entity_instanc
     if not app and ifc.schema == "IFC2X3":
         raise Exception(
             "Please create an application to continue. See the owner.create_owner_history docs for more info."
-            "https://blenderbim.org/docs-python/autoapi/ifcopenshell/api/owner/create_owner_history/index.html"
+            "https://docs.ifcopenshell.org/autoapi/ifcopenshell/api/owner/create_owner_history/index.html"
         )
     return (app or [None])[0]
 
@@ -58,7 +58,7 @@ def get_user(ifc: ifcopenshell.file) -> Union[ifcopenshell.entity_instance, None
     if not pao and ifc.schema == "IFC2X3":
         raise Exception(
             "Please create a user to continue. See the owner.create_owner_history docs for more info."
-            "https://blenderbim.org/docs-python/autoapi/ifcopenshell/api/owner/create_owner_history/index.html"
+            "https://docs.ifcopenshell.org/autoapi/ifcopenshell/api/owner/create_owner_history/index.html"
         )
     return (pao or [None])[0]
 

src/ifcopenshell-python/ifcopenshell/api/sequence/edit_task_time.py

@@ -17,12 +17,19 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import datetime
+import ifcopenshell.util.constraint
 import ifcopenshell.util.date
 import ifcopenshell.util.sequence
+from typing import Any, Optional
 
 
 class Usecase:
-    def __init__(self, file, task_time=None, attributes=None):
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        task_time: ifcopenshell.entity_instance,
+        attributes: Optional[dict[str, Any]] = None,
+    ):
         """Edits the attributes of an IfcTaskTime
 
         For more information about the attributes and data types of an
@@ -55,7 +62,7 @@ class Usecase:
         self.file = file
         self.settings = {"task_time": task_time, "attributes": attributes or {}}
 
-    def execute(self):
+    def execute(self) -> None:
         self.task = self.get_task()
         self.calendar = ifcopenshell.util.sequence.derive_calendar(self.task)
 
@@ -169,12 +176,12 @@ class Usecase:
             duration, "IfcDuration"
         )
 
-    def get_task(self):
-        return [
+    def get_task(self) -> ifcopenshell.entity_instance:
+        return next(
             e
             for e in self.file.get_inverse(self.settings["task_time"])
             if e.is_a("IfcTask")
-        ][0]
+        )
 
     def handle_resource_calculation(self):
         resources = ifcopenshell.util.sequence.get_task_resources(self.task, is_deep=False)

src/ifcopenshell-python/ifcopenshell/api/sequence/edit_work_time.py

@@ -17,10 +17,16 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell.util.date
+from typing import Any, Optional
 
 
 class Usecase:
-    def __init__(self, file, work_time=None, attributes=None):
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        work_time: ifcopenshell.entity_instance,
+        attributes: Optional[dict[str, Any]] = None,
+    ):
         """Edits the attributes of an IfcWorkTime
 
         For more information about the attributes and data types of an
@@ -53,13 +59,15 @@ class Usecase:
         self.file = file
         self.settings = {"work_time": work_time, "attributes": attributes or {}}
 
-    def execute(self):
+    def execute(self) -> None:
         for name, value in self.settings["attributes"].items():
             if name in ("Start", "StartDate"):
                 value = ifcopenshell.util.date.datetime2ifc(value, "IfcDate")
+                # 4 IfcWorktime Start
                 self.settings["work_time"][4] = value
             elif name in ("Finish", "FinishDate"):
                 value = ifcopenshell.util.date.datetime2ifc(value, "IfcDate")
+                # 5 IfcWorktime Finish
                 self.settings["work_time"][5] = value
             else:
                 setattr(self.settings["work_time"], name, value)

src/ifcopenshell-python/ifcopenshell/api/spatial/dereference_structure.py

@@ -22,11 +22,16 @@ import ifcopenshell.util.element
 
 
 class Usecase:
-    def __init__(self, file, product=None, relating_structure=None):
-        """Dereferences the a product and space
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        products: list[ifcopenshell.entity_instance],
+        relating_structure: ifcopenshell.entity_instance,
+    ):
+        """Dereferences a list of products and space
 
-        :param product: The physical IfcElement that exists in the space.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :param products: The list of physical IfcElements that exists in the space.
+        :type products: list[ifcopenshell.entity_instance.entity_instance]
         :param relating_structure: The IfcSpatialStructureElement element, such
             as IfcBuilding, IfcBuildingStorey, or IfcSpace that the element
             exists in.
@@ -59,23 +64,24 @@ class Usecase:
             ifcopenshell.api.run("spatial.assign_container", model, products=[column], relating_structure=storey1)
 
             # And referenced in the others
-            ifcopenshell.api.run("spatial.reference_structure", model, product=column, relating_structure=storey2)
-            ifcopenshell.api.run("spatial.reference_structure", model, product=column, relating_structure=storey3)
+            ifcopenshell.api.run("spatial.reference_structure", model, products=[column], relating_structure=storey2)
+            ifcopenshell.api.run("spatial.reference_structure", model, products=[column], relating_structure=storey3)
 
             # Actually, it only goes up to storey 2.
-            ifcopenshell.api.run("spatial.dereference_structure", model, product=column, relating_structure=storey3)
+            ifcopenshell.api.run("spatial.dereference_structure", model, products=[column], relating_structure=storey3)
         """
         self.file = file
-        self.settings = {"product": product, "relating_structure": relating_structure}
+        self.settings = {"products": products, "relating_structure": relating_structure}
 
-    def execute(self):
-        for rel in self.settings["product"].ReferencedInStructures:
-            if rel.RelatingStructure != self.settings["relating_structure"]:
+    def execute(self) -> None:
+        products = set(self.settings["products"])
+        for rel in self.settings["relating_structure"].ReferencesElements:
+            related_elements = set(rel.RelatedElements)
+            if not related_elements.intersection(products):
                 continue
-            related_elements = list(rel.RelatedElements)
-            related_elements.remove(self.settings["product"])
+            related_elements = related_elements - products
             if related_elements:
-                rel.RelatedElements = related_elements
+                rel.RelatedElements = list(related_elements)
                 ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
             else:
                 history = rel.OwnerHistory

src/ifcopenshell-python/ifcopenshell/api/spatial/reference_structure.py

@@ -18,11 +18,18 @@
 
 import ifcopenshell
 import ifcopenshell.api
+import ifcopenshell.util.element
+from typing import Union
 
 
 class Usecase:
-    def __init__(self, file, product=None, relating_structure=None):
-        """Denote that a product is related to a spatial structure
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        products: list[ifcopenshell.entity_instance],
+        relating_structure: ifcopenshell.entity_instance,
+    ):
+        """Denote that a list products is related to a list of spatial structures
 
         This is similar to ifcopenshell.api.spatial.assign_container, except
         that containment can only occur between a product and a single spatial
@@ -39,13 +46,15 @@ class Usecase:
         Referencing is non-hierarchical, so a door may be referenced in multiple
         spaces simultaneously.
 
-        :param product: The physical IfcElement that exists in the space.
-        :type product: ifcopenshell.entity_instance.entity_instance
+        :param products: The list of physical IfcElements that exists in the space.
+        :type products: list[ifcopenshell.entity_instance.entity_instance]
         :param relating_structure: The IfcSpatialStructureElement element, such
             as IfcBuilding, IfcBuildingStorey, or IfcSpace that the element
             exists in.
+        :type relating_structure: ifcopenshell.entity_instance.entity_instance
         :return: The IfcRelReferencedInSpatialStructure relationship instance
-        :rtype: ifcopenshell.entity_instance.entity_instance
+            or `None` if `products` was an empty list.
+        :rtype: Union[ifcopenshell.entity_instance, None]
 
         Example:
 
@@ -73,37 +82,43 @@ class Usecase:
             ifcopenshell.api.run("spatial.assign_container", model, products=[column], relating_structure=storey1)
 
             # And referenced in the others
-            ifcopenshell.api.run("spatial.reference_structure", model, product=column, relating_structure=storey2)
-            ifcopenshell.api.run("spatial.reference_structure", model, product=column, relating_structure=storey3)
+            ifcopenshell.api.run(
+                "spatial.reference_structure", model, products=[column], relating_structure=[storey2, storey3]
+            )
         """
         self.file = file
         self.settings = {
-            "product": product,
+            "products": products,
             "relating_structure": relating_structure,
         }
 
-    def execute(self):
-        referenced_in_structures = self.settings["product"].ReferencedInStructures
-        references_elements = self.settings["relating_structure"].ReferencesElements
+    def execute(self) -> Union[ifcopenshell.entity_instance, None]:
+        structure = self.settings["relating_structure"]
+        products = set(self.settings["products"])
 
-        for rel in referenced_in_structures:
-            if rel.RelatingStructure == self.settings["relating_structure"]:
-                return
+        if not products:
+            return
 
-        if references_elements:
-            related_elements = list(references_elements[0].RelatedElements)
-            related_elements.append(self.settings["product"])
-            references_elements[0].RelatedElements = related_elements
-            ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": references_elements[0]})
-        else:
-            references_elements = self.file.create_entity(
+        referenced = ifcopenshell.util.element.get_structure_referenced_elements(structure)
+        products_to_assign = products - referenced
+        rel = next(iter(structure.ReferencesElements), None)
+
+        if not products_to_assign:
+            return rel
+
+        if rel is None:
+            rel = self.file.create_entity(
                 "IfcRelReferencedInSpatialStructure",
                 **{
                     "GlobalId": ifcopenshell.guid.new(),
                     "OwnerHistory": ifcopenshell.api.run("owner.create_owner_history", self.file),
-                    "RelatedElements": [self.settings["product"]],
-                    "RelatingStructure": self.settings["relating_structure"],
+                    "RelatedElements": list(products_to_assign),
+                    "RelatingStructure": structure,
                 }
             )
+        else:
+            related_elements = set(rel.RelatedElements) | products_to_assign
+            rel.RelatedElements = list(related_elements)
+            ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
 
-        return references_elements
+        return rel

src/ifcopenshell-python/ifcopenshell/entity_instance.py

@@ -30,7 +30,7 @@ import functools
 import subprocess
 import sys
 import time
-from typing import Union, Any, Callable, TypeVar
+from typing import Union, Any, Callable, TypeVar, overload
 
 from . import ifcopenshell_wrapper
 from . import settings
@@ -42,66 +42,8 @@ except ImportError as e:
 
 T = TypeVar("T")
 
-
-def set_derived_attribute(*args):
-    raise TypeError("Unable to set derived attribute")
-
-
-def set_unsupported_attribute(*args):
-    raise TypeError("This is an unsupported attribute type")
-
-
-# For every schema and its entities populate a list
-# of functions for every entity attribute (including
-# inherited attributes) to set that particular
-# attribute by index.
-# For example. IFC2X3.IfcWall with have a list of
-# 9 methods. The first will point at
-# ifcopenshell.ifcopenshell_wrapper.entity_instance.setArgumentAsString
-# because the first attribute GlobalId ultimately
-# is of type string.
-# Previously, resolving the appropriate function was
-# done for each invocation of __setitem__. Now this
-# mapping is built once during initialization of the
-# module.
-_method_dict = {}
-
-
-def register_schema_attributes(schema):
-    for decl in schema.declarations():
-        if hasattr(decl, "argument_types"):
-            fq_name = ".".join((schema.name(), decl.name()))
-
-            # get type strings as reported by IfcOpenShell C++
-            type_strs = decl.argument_types()
-
-            # convert case for setter function
-            type_strs = [x.title().replace(" ", "") for x in type_strs]
-
-            # binary and enumeration are passed from python as string as well
-            type_strs = [x.replace("Binary", "String") for x in type_strs]
-            type_strs = [x.replace("Enumeration", "String") for x in type_strs]
-
-            # prefix to get method names
-            fn_names = ["setArgumentAs" + x for x in type_strs]
-
-            # resolve to actual functions in wrapper
-            functions = [
-                set_derived_attribute
-                if mname == "setArgumentAsDerived"
-                else set_unsupported_attribute
-                if mname == "setArgumentAsUnknown"
-                else getattr(ifcopenshell_wrapper.entity_instance, mname)
-                for mname in fn_names
-            ]
-
-            _method_dict[fq_name] = functions
-
-
-for nm in ifcopenshell_wrapper.schema_names():
-    schema = ifcopenshell_wrapper.schema_by_name(nm)
-    register_schema_attributes(schema)
-
+# poor man's enum
+ATTR_INVALID, ATTR_FORWARD, ATTR_INVERSE, ATTR_FORWARD_DERIVED = range(4)
 
 class entity_instance(object):
     """Base class for all IFC objects.
@@ -120,44 +62,22 @@ class entity_instance(object):
         >>> #423=IfcProductDefinitionShape($,$,(#409,#421))
     """
 
-    wrapped_data: ifcopenshell_wrapper.entity_instance
-
-    def __init__(self, e, file=None):
-        if isinstance(e, tuple):
-            e = ifcopenshell_wrapper.new_IfcBaseClass(*e)
-        super(entity_instance, self).__setattr__("wrapped_data", e)
-        super(entity_instance, self).__setattr__("method_list", None)
-
-        # Make sure the file is not gc'ed while we have live instances
-        self.wrapped_data.file = file
-
-    def __del__(self):
-        """
-        #2471 while the precise chain of action is unclear, creating
-        instance references prevents file gc, even with all instance
-        refs deleted. This is a work-around for that.
-        """
-        self.wrapped_data.file = None
-
     @property
     def file(self):
         # ugh circular imports, name collisions
         from . import file
 
-        return file.from_pointer(self.wrapped_data.file_pointer())
+        return file.from_pointer(self.file_pointer())
 
     def __getattr__(self, name):
-        INVALID, FORWARD, INVERSE = range(3)
-        attr_cat = self.wrapped_data.get_attribute_category(name)
-        if attr_cat == FORWARD:
-            idx = self.wrapped_data.get_argument_index(name)
-            if _method_dict[self.is_a(True)][idx] != set_derived_attribute:
-                # A bit ugly, but we fall through to derived attribute handling below
-                return entity_instance.wrap_value(self.wrapped_data.get_argument(idx), self.wrapped_data.file)
-        elif attr_cat == INVERSE:
-            vs = entity_instance.wrap_value(self.wrapped_data.get_inverse(name), self.wrapped_data.file)
+        attr_cat = self.get_attribute_category(name)
+        if attr_cat == ATTR_FORWARD:
+            idx = self.get_argument_index(name)
+            return self.get_argument(idx)
+        elif attr_cat == ATTR_INVERSE:
+            vs = self.get_inverse(name)
             if settings.unpack_non_aggregate_inverses:
-                schema_name = self.wrapped_data.is_a(True).split(".")[0]
+                schema_name = self.is_a(True).split(".")[0]
                 ent = ifcopenshell_wrapper.schema_by_name(schema_name).declaration_by_name(self.is_a())
                 inv = [i for i in ent.all_inverse_attributes() if i.name() == name][0]
                 if (inv.bound1(), inv.bound2()) == (-1, -1):
@@ -166,9 +86,9 @@ class entity_instance(object):
                     else:
                         vs = None
             return vs
-
+    
         # derived attribute perhaps?
-        schema_name = self.wrapped_data.is_a(True).split(".")[0]
+        schema_name = self.is_a(True).split(".")[0]
         try:
             rules = importlib.import_module(f"ifcopenshell.express.rules.{schema_name}")
         except:
@@ -180,21 +100,21 @@ class entity_instance(object):
                 subprocess.run([sys.executable, "-m", "ifcopenshell.express.rule_compiler", schema_path, fn], check=True)
                 time.sleep(1.)
             rules = importlib.import_module(schema_name)
-
+    
         def yield_supertypes():
             decl = ifcopenshell_wrapper.schema_by_name(schema_name).declaration_by_name(self.is_a())
             while decl:
                 yield decl.name()
                 decl = decl.supertype()
-
+    
         for sty in yield_supertypes():
             fn = getattr(rules, f"calc_{sty}_{name}", None)
             if fn:
                 return fn(self)
-
+    
         if attr_cat != FORWARD:
             raise AttributeError(
-                "entity instance of type '%s' has no attribute '%s'" % (self.wrapped_data.is_a(True), name)
+                "entity instance of type '%s' has no attribute '%s'" % (self.is_a(True), name)
             )
 
     @staticmethod
@@ -235,26 +155,6 @@ class entity_instance(object):
         else:
             return value
 
-    @staticmethod
-    def wrap_value(v, file):
-        def wrap(e):
-            return entity_instance(e, file)
-
-        def is_instance(e):
-            return isinstance(e, ifcopenshell_wrapper.entity_instance)
-
-        return entity_instance.walk(is_instance, wrap, v)
-
-    @staticmethod
-    def unwrap_value(v):
-        def unwrap(e):
-            return e.wrapped_data
-
-        def is_instance(e):
-            return isinstance(e, entity_instance)
-
-        return entity_instance.walk(is_instance, unwrap, v)
-
     def attribute_type(self, attr: int) -> str:
         """Return the data type of a positional attribute of the element
 
@@ -262,8 +162,8 @@ class entity_instance(object):
         :type attr: int
         :rtype: string
         """
-        attr_idx = attr if isinstance(attr, numbers.Integral) else self.wrapped_data.get_argument_index(attr)
-        return self.wrapped_data.get_argument_type(attr_idx)
+        attr_idx = attr if isinstance(attr, numbers.Integral) else self.get_argument_index(attr)
+        return self.get_argument_type(attr_idx)
 
     def attribute_name(self, attr_idx: int) -> str:
         """Return the name of a positional attribute of the element
@@ -272,37 +172,28 @@ class entity_instance(object):
         :type attr_idx: int
         :rtype: string
         """
-        return self.wrapped_data.get_argument_name(attr_idx)
+        return self.get_argument_name(attr_idx)
 
     def __setattr__(self, key: str, value: Any) -> None:
-        index = self.wrapped_data.get_argument_index(key)
+        index = self.get_argument_index(key)
         self[index] = value
 
     def __getitem__(self, key: int) -> Any:
         if key < 0 or key >= len(self):
             raise IndexError("Attribute index {} out of range for instance of type {}".format(key, self.is_a()))
-        return entity_instance.wrap_value(self.wrapped_data.get_argument(key), self.wrapped_data.file)
+        return self.get_argument(key)
 
     def __setitem__(self, idx: int, value: T) -> T:
-        if self.wrapped_data.file and self.wrapped_data.file.transaction:
-            self.wrapped_data.file.transaction.store_edit(self, idx, value)
-
-        if self.method_list is None:
-            super(entity_instance, self).__setattr__("method_list", _method_dict[self.is_a(True)])
-
-        method = self.method_list[idx]
-
-        if value is None:
-            if method is not set_derived_attribute:
-                self.wrapped_data.setArgumentAsNull(idx)
-        else:
-            self.method_list[idx](self.wrapped_data, idx, entity_instance.unwrap_value(value))
-
+        if self.file and self.file.transaction:
+            self.file.transaction.store_edit(self, idx, value)
+    
+        self.setAttribute(idx, value)
+    
         return value
-
+    
     def __len__(self):
         return len(self.wrapped_data)
-
+    
     def __repr__(self):
         return repr(self.wrapped_data)
 
@@ -315,17 +206,27 @@ class entity_instance(object):
         the specific control directives.
         """
 
-        return self.wrapped_data.to_string(valid_spf)
+        return self.to_string(valid_spf)
 
-    def is_a(self, *args) -> Union[str, bool]:
+    @overload
+    def is_a(self) -> str: ...
+    @overload
+    def is_a(self, ifc_class: str) -> bool: ...
+    @overload
+    def is_a(self, with_schema: bool) -> str: ...
+    def is_a(self, *args: Union[str, bool]) -> Union[str, bool]:
         """Return the IFC class name of an instance, or checks if an instance belongs to a class.
 
         The check will also return true if a parent class name is provided.
 
         :param args: If specified, is a case insensitive IFC class name to check
-        :type args: string
+            or if specified as a boolean then will define whether
+            returned IFC class name should include schema name
+            (e.g. "IFC4.IfcWall" if `True` and "IfcWall" if `False`).
+            If omitted will act as `False`.
+        :type args: Union[str, bool]
         :returns: Either the name of the class, or a boolean if it passes the check
-        :rtype: string|bool
+        :rtype: Union[str, bool]
 
         Example:
 
@@ -338,19 +239,19 @@ class entity_instance(object):
             f.is_a('IfcPerson')
             >>> True
         """
-        return self.wrapped_data.is_a(*args)
+        return self.is_a(*args)
 
     def id(self) -> int:
         """Return the STEP numerical identifier
 
         :rtype: int
         """
-        return self.wrapped_data.id()
+        return self.id()
 
     def __eq__(self, other):
         if not isinstance(self, type(other)):
             return False
-        elif None in (self.wrapped_data.file, other.wrapped_data.file):
+        elif None in (self.file, other.file):
             # when not added to a file, we can only compare attribute values
             # and we need this for where rule evaluation
             return self.get_info(recursive=True, include_identifier=False) == other.get_info(
@@ -363,10 +264,10 @@ class entity_instance(object):
             if self.id():
                 return self.wrapped_data == other.wrapped_data
             else:
-                return (self.is_a(), self[0], self.wrapped_data.file_pointer()) == (
+                return (self.is_a(), self[0], self.file_pointer()) == (
                     other.is_a(),
                     other[0],
-                    other.wrapped_data.file_pointer(),
+                    other.file_pointer(),
                 )
 
     def is_entity(self) -> bool:
@@ -375,7 +276,7 @@ class entity_instance(object):
         Returns:
             bool: True if the instance is an entity
         """
-        schema_name = self.wrapped_data.is_a(True).split(".")[0]
+        schema_name = self.is_a(True).split(".")[0]
         decl = ifcopenshell_wrapper.schema_by_name(schema_name).declaration_by_name(self.is_a())
         return isinstance(decl, ifcopenshell_wrapper.entity)
 
@@ -449,17 +350,17 @@ class entity_instance(object):
         # step id. Selected type instances (such as IfcPropertySingleValue.NominalValue
         # always have id=0, so we hash <type, value, file pointer>
         if self.id():
-            return hash((self.id(), self.wrapped_data.file_pointer()))
+            return hash((self.id(), self.file_pointer()))
         else:
-            return hash((self.is_a(), self[0], self.wrapped_data.file_pointer()))
+            return hash((self.is_a(), self[0], self.file_pointer()))
 
     def __dir__(self):
         return sorted(
             set(
                 itertools.chain(
                     dir(type(self)),
-                    map(str, self.wrapped_data.get_attribute_names()),
-                    map(str, self.wrapped_data.get_inverse_attribute_names()),
+                    map(str, self.get_attribute_names()),
+                    map(str, self.get_inverse_attribute_names()),
                 )
             )
         )
@@ -503,7 +404,7 @@ class entity_instance(object):
                 logging.exception("unhandled exception while getting id / type info on {}".format(self))
             for i in range(len(self)):
                 try:
-                    if self.wrapped_data.get_attribute_names()[i] in ignore:
+                    if self.get_attribute_names()[i] in ignore:
                         continue
                     attr_value = self[i]
 
@@ -538,7 +439,8 @@ class entity_instance(object):
 
         return return_type(_())
 
-    __dict__ = property(get_info)
+    # @todo this is no longer possible with the direct integration into the swig type
+    # __dict__ = property(get_info)
 
     def get_info_2(self, include_identifier=True, recursive=False, return_type=dict, ignore=()):
         """More perfomant version of `.get_info()` but with limited arguments values.\n

src/ifcopenshell-python/ifcopenshell/express/implementation.py

@@ -41,6 +41,17 @@ class Implementation(codegen.Base):
 
         write = lambda str, **kwargs: enumeration_functions.append(str % kwargs)
 
+        collections_by_type = (
+            ("entity", mapping.schema.entities),
+            ("type_declaration", mapping.schema.simpletypes),
+            ("select_type", mapping.schema.selects),
+            ("enumeration_type", mapping.schema.enumerations),
+        )
+        self.names = []
+        for _, collection in collections_by_type:
+            self.names.extend(collection.keys())
+        self.names.sort(key=str.lower)
+
         for name, enum in mapping.schema.enumerations.items():
             short_name = name[:-4] if name.endswith("Enum") else name
             context = locals()
@@ -50,6 +61,7 @@ class Implementation(codegen.Base):
                 name=name,
                 schema_name=schema_name,
                 schema_name_upper=schema_name_upper,
+                index_in_schema=self.names.index(str(name)),
                 values=catc(map(stringify, enum.values)),
                 from_string_statements=catnl(
                     templates.enum_from_string_stmt % dict(context, **locals()) for value in enum.values
@@ -61,7 +73,8 @@ class Implementation(codegen.Base):
                 templates.select_function,
                 name=name,
                 schema_name=schema_name,
-                schema_name_upper=schema_name_upper
+                schema_name_upper=schema_name_upper,
+                index_in_schema=self.names.index(str(name)),
             )
 
         write = lambda str, **kwargs: entity_implementations.append(str % kwargs)
@@ -140,6 +153,8 @@ class Implementation(codegen.Base):
                             return templates.set_attr_stmt_enum
                         elif arg["is_templated_list"] and not (select or simple or express):
                             return templates.set_attr_stmt_array
+                        elif arg["full_type"].endswith('*'):
+                            return templates.set_attr_instance
                         else:
                             return templates.set_attr_stmt
 
@@ -159,6 +174,7 @@ class Implementation(codegen.Base):
                             "non_optional_type": arg["non_optional_type"].replace("::Value", ""),
                             "star_if_optional": "*" if "boost::optional" in arg["full_type"] else "",
                             "check_optional_set_begin": "if (v) {" if "boost::optional" in arg["full_type"] else "",
+                            "check_optional_set_else": "} else {" if "boost::optional" in arg["full_type"] else "if constexpr (false)",
                             "check_optional_set_end": "}" if "boost::optional" in arg["full_type"] else "",
                         },
                     )
@@ -175,6 +191,8 @@ class Implementation(codegen.Base):
                         if arg["is_templated_list"]
                         else templates.constructor_stmt_enum
                         if arg["is_enum"]
+                        else templates.constructor_stmt_instance
+                        if arg["full_type"].endswith('*')
                         else templates.constructor_stmt
                     )
                     impl = tmpl % {
@@ -208,6 +226,7 @@ class Implementation(codegen.Base):
                     "body": templates.get_inverse
                     % {
                         "type": i.entity,
+                        "type_index": self.names.index(i.entity),
                         "index": get_attribute_index(i.entity, i.attribute),
                         "schema_name": schema_name,
                         "schema_name_upper": schema_name_upper,
@@ -233,6 +252,7 @@ class Implementation(codegen.Base):
                 superclass=superclass,
                 schema_name=schema_name,
                 schema_name_upper=schema_name_upper,
+                index_in_schema=self.names.index(str(name)),
             )
 
         selectable_simple_types = sorted(
@@ -306,6 +326,7 @@ class Implementation(codegen.Base):
 
             def compose(params, schema_name=schema_name, schema_name_upper=schema_name_upper):
                 class_name, attr_type, superclass, superclass_init, name, tmpl, return_type, args, body = params
+                index_in_schema = self.names.index(str(class_name))
                 underlying_type = mapping.list_instance_type(type)
                 arguments = ",".join(args)
                 body = body % locals()
@@ -347,6 +368,7 @@ class Implementation(codegen.Base):
             )
             simple_type_impl.append("")
 
+        """
         external_definitions = (
             [("extern entity* %s_%%s_type;" % schema_name_upper) % n for n in mapping.schema.entities.keys()]
             + [
@@ -362,6 +384,8 @@ class Implementation(codegen.Base):
                 for n in mapping.schema.selects.keys()
             ]
         )
+        """
+        external_definitions = ["extern declaration* %s_types[%d];" % (schema_name_upper, len(self.names))]
 
         self.str = templates.implementation % {
             "schema_name_upper": schema_name_upper,

src/ifcopenshell-python/ifcopenshell/express/schema_class.py

@@ -18,6 +18,7 @@
 
 
 import operator
+import re
 
 import nodes
 import codegen
@@ -116,8 +117,26 @@ class LateBoundSchemaInstantiator:
             elem.this.disown()
 
 
+class string_pool:
+    def __init__(self, fn):
+        self.di = {}
+        self.fn = fn
+    def append(self, v):
+        def _():
+            if i := self.di.get(v):
+                return i
+            else:
+                i = len(self.di)
+                self.di[v] = i
+                return i
+        return self.fn(_())
+    def __iter__(self):
+        return iter(self.di.keys())
+
+
 class EarlyBoundCodeWriter:
     def __init__(self, schema_name):
+        self.strings = string_pool(lambda i: "strings[%d]" % i)
         self.schema_name = schema_name
         self.schema_name_title = schema_name.capitalize()
 
@@ -125,7 +144,9 @@ class EarlyBoundCodeWriter:
             "",
             '#include "../ifcparse/IfcSchema.h"',
             '#include "../ifcparse/%(schema_name_title)s.h"' % self.__dict__,
+            '#include <string>',
             "",
+            'using namespace std::string_literals;',
             "using namespace IfcParse;",
             "",
         ]
@@ -146,145 +167,138 @@ class EarlyBoundCodeWriter:
 
     def declare(self, definition_type, name):
         schema_name = self.schema_name
-        self.statements.append("%(definition_type)s* %(schema_name)s_%(name)s_type = 0;" % locals())
+        # self.statements.append("%(definition_type)s* %(schema_name)s_%(name)s_type = 0;" % locals())
         self.names.append(name)
 
     def begin_schema(self):
         self.names.sort(key=str.lower)
+        schema_name = self.schema_name
+        num_names = len(self.names)
+        self.statements.append("declaration* %(schema_name)s_types[%(num_names)d] = {nullptr};" % locals())
+
+        self.statements.append("{string_pool_placeholder}")
 
         self.statements.append("{factory_placeholder}")
 
-        self.statements.append(
-            """
-#if defined(__clang__)
-__attribute__((optnone))
-#elif defined(__GNUC__) || defined(__GNUG__)
-#pragma GCC push_options
-#pragma GCC optimize ("O0")
-#elif defined(_MSC_VER)
-#pragma optimize("", off)
-#endif
-        """
-        )
+#         self.statements.append(
+#             """
+# #if defined(__clang__)
+# __attribute__((optnone))
+# #elif defined(__GNUC__) || defined(__GNUG__)
+# #pragma GCC push_options
+# #pragma GCC optimize ("O0")
+# #elif defined(_MSC_VER)
+# #pragma optimize("", off)
+# #endif
+#         """
+#         )
         self.statements.append("IfcParse::schema_definition* %s_populate_schema() {" % self.schema_name)
 
     def typedef(self, name, declared_type):
         schema_name = self.schema_name
         index_in_schema = self.names.index(name)
+        ref = self.strings.append(name)
         self.statements.append(
-            '    %(schema_name)s_%(name)s_type = new type_declaration("%(name)s", %(index_in_schema)d, %(declared_type)s);'
+            '    %(schema_name)s_types[%(index_in_schema)d] = new type_declaration(%(ref)s, %(index_in_schema)d, %(declared_type)s);'
             % locals()
         )
 
     def enumeration(self, name, enum):
         schema_name = self.schema_name
         index_in_schema = self.names.index(name)
-        self.statements.append("    {")
-        self.statements.append("        std::vector<std::string> items; items.reserve(%d);" % len(enum.values))
-        self.statements.extend(map(lambda v: '        items.push_back("%s");' % v, sorted(enum.values)))
+        ref = self.strings.append(name)
+        items = ",".join(self.strings.append(v) for v in sorted(enum.values))
         self.statements.append(
-            '        %(schema_name)s_%(name)s_type = new enumeration_type("%(name)s", %(index_in_schema)d, items);'
+            '    %(schema_name)s_types[%(index_in_schema)d] = new enumeration_type(%(ref)s, %(index_in_schema)d, {%(items)s});'
             % locals()
         )
-        self.statements.append("    }")
 
     def entity(self, name, type):
         schema_name = self.schema_name
         index_in_schema = self.names.index(name)
-        supertype = "0" if len(type.supertypes) == 0 else "%s_%s_type" % (self.schema_name, type.supertypes[0])
+        ref = self.strings.append(name)
+        supertype = "0" if len(type.supertypes) == 0 else "%s_types[%d]" % (self.schema_name, self.names.index(type.supertypes[0]))
         is_abstract = "true" if type.abstract else "false"
         self.statements.append(
-            '    %(schema_name)s_%(name)s_type = new entity("%(name)s", %(is_abstract)s, %(index_in_schema)d, %(supertype)s);'
+            '    %(schema_name)s_types[%(index_in_schema)d] = new entity(%(ref)s, %(is_abstract)s, %(index_in_schema)d, (entity*) %(supertype)s);'
             % locals()
         )
 
     def select(self, name, type):
         schema_name = self.schema_name
         index_in_schema = self.names.index(name)
-        self.statements.append("    {")
-        self.statements.append("        std::vector<const declaration*> items; items.reserve(%d);" % len(type.values))
-        self.statements.extend(
-            map(lambda v: "        items.push_back(%s_%s_type);" % (self.schema_name, v), sorted(map(str, type.values)))
+        ref = self.strings.append(name)
+        items = ",".join(
+            map(lambda v: "%s_types[%d]" % (self.schema_name, self.names.index(v)), sorted(map(str, type.values)))
         )
         self.statements.append(
-            '        %(schema_name)s_%(name)s_type = new select_type("%(name)s", %(index_in_schema)d, items);'
+            '    %(schema_name)s_types[%(index_in_schema)d] = new select_type(%(ref)s, %(index_in_schema)d, {%(items)s});'
             % locals()
         )
-        self.statements.append("    }")
 
     def entity_attributes(self, name, attribute_definitions, is_derived):
         schema_name = self.schema_name
-        self.statements.append("    {")
-        self.statements.append(
-            "        std::vector<const attribute*> attributes; attributes.reserve(%d);" % len(attribute_definitions)
-        )
-        for attr_name, decl_type, optional in attribute_definitions:
-            optional_cpp = str(optional).lower()
-            self.statements.append(
-                '        attributes.push_back(new attribute("%(attr_name)s", %(decl_type)s, %(optional_cpp)s));'
-                % locals()
-            )
-        self.statements.append("        std::vector<bool> derived; derived.reserve(%d);" % len(is_derived))
-        self.statements.append(
-            "        " + " ".join(map(lambda b: "derived.push_back(%s);" % str(b).lower(), is_derived))
-        )
-        self.statements.append("        %(schema_name)s_%(name)s_type->set_attributes(attributes, derived);" % locals())
-        self.statements.append("    }")
+        index_in_schema = self.names.index(name)
+        def _():
+            index_in_schema = self.names.index(name)
+            schema_name = self.schema_name
+            for attr_name, decl_type, optional in attribute_definitions:
+                attr_name_ref = self.strings.append(attr_name)
+                optional_cpp = str(optional).lower()
+                yield 'new attribute(%(attr_name_ref)s, %(decl_type)s, %(optional_cpp)s)' % locals()
+        attributes = ",".join(_())
+        derived = ",".join(map(lambda b: str(b).lower(), is_derived))
+        self.statements.append("    ((entity*)%(schema_name)s_types[%(index_in_schema)d])->set_attributes({%(attributes)s}, {%(derived)s});" % locals())
 
     def inverse_attributes(self, name, inv_attrs):
         schema_name = self.schema_name
-        self.statements.append("    {")
-        self.statements.append(
-            "        std::vector<const inverse_attribute*> attributes; attributes.reserve(%d);" % len(inv_attrs)
-        )
-        for attr_name, aggr_type, bound1, bound2, entity_ref, attribute_entity, attribute_entity_index in inv_attrs:
-            self.statements.append(
-                '        attributes.push_back(new inverse_attribute("%(attr_name)s", inverse_attribute::%(aggr_type)s_type, %(bound1)d, %(bound2)d, %(schema_name)s_%(entity_ref)s_type, %(schema_name)s_%(attribute_entity)s_type->attributes()[%(attribute_entity_index)d]));'
-                % locals()
-            )
-        self.statements.append("        %(schema_name)s_%(name)s_type->set_inverse_attributes(attributes);" % locals())
-        self.statements.append("    }")
+        index_in_schema = self.names.index(name)
+        def _():
+            schema_name = self.schema_name
+            index_in_schema = self.names.index(name)
+            for attr_name, aggr_type, bound1, bound2, entity_ref, attribute_entity, attribute_entity_index in inv_attrs:
+                attr_name_ref = self.strings.append(attr_name)
+                opposite_index_in_schema = self.names.index(entity_ref)
+                opposite1 = '%(schema_name)s_types[%(opposite_index_in_schema)d]' % locals()
+                opposite_index_in_schema = self.names.index(attribute_entity)
+                opposite2 = '%(schema_name)s_types[%(opposite_index_in_schema)d]' % locals()
+                yield 'new inverse_attribute(%(attr_name_ref)s, inverse_attribute::%(aggr_type)s_type, %(bound1)d, %(bound2)d, ((entity*) %(opposite1)s), ((entity*) %(opposite2)s)->attributes()[%(attribute_entity_index)d])' % locals()
+        attributes = ",".join(_())
+        self.statements.append("    ((entity*) %(schema_name)s_types[%(index_in_schema)d])->set_inverse_attributes({%(attributes)s});" % locals())
 
     def entity_subtypes(self, name, tys):
         schema_name = self.schema_name
-        self.statements.append("    {")
-        self.statements.append("        std::vector<const entity*> defs; defs.reserve(%d);" % len(tys))
-        self.statements.append(
-            ("        " + "".join(map(lambda t: ("defs.push_back(%%(schema_name)s_%s_type);" % t), tys))) % locals()
-        )
-        self.statements.append("        %(schema_name)s_%(name)s_type->set_subtypes(defs);" % locals())
-        self.statements.append("    }")
+        index_in_schema = self.names.index(name)
+        subtypes = ",".join(map(lambda t: ("((entity*) %%(schema_name)s_types[%d])" % self.names.index(t)), tys)) % locals()
+        self.statements.append("    ((entity*) %(schema_name)s_types[%(index_in_schema)d])->set_subtypes({%(subtypes)s});" % locals())
 
     def finalize(self, can_be_instantiated_set):
         schema_name = self.schema_name
         schema_name_title = self.schema_name.capitalize()
-
-        num_declarations = len(self.names)
-
-        self.statements.append("")
+        def _():
+            schema_name = self.schema_name
+            schema_name_title = self.schema_name.capitalize()
+            for type_name in self.names:
+                index_in_schema = self.names.index(type_name)
+                yield "%(schema_name)s_types[%(index_in_schema)d]" % locals()
+        declarations = ",".join(_())
+        schema_name_ref = self.strings.append(schema_name)
         self.statements.append(
-            "    std::vector<const declaration*> declarations; declarations.reserve(%(num_declarations)d);" % locals()
-        )
-        for type_name in self.names:
-            self.statements.append("    declarations.push_back(%(schema_name)s_%(type_name)s_type);" % locals())
-
-        self.statements.append(
-            '    return new schema_definition("%(schema_name)s", declarations, new %(schema_name)s_instance_factory());'
+            '    return new schema_definition(%(schema_name_ref)s, {%(declarations)s}, new %(schema_name)s_instance_factory());'
             % locals()
         )
+        self.statements.append("}");
 
-        self.statements.extend(("}", ""))
-
-        self.statements.append(
-            """
-#if defined(__clang__)
-#elif defined(__GNUC__) || defined(__GNUG__)
-#pragma GCC pop_options
-#elif defined(_MSC_VER)
-#pragma optimize("", on)
-#endif
-        """
-        )
+#         self.statements.append(
+#             """
+# #if defined(__clang__)
+# #elif defined(__GNUC__) || defined(__GNUG__)
+# #pragma GCC pop_options
+# #elif defined(_MSC_VER)
+# #pragma optimize("", on)
+# #endif
+#         """
+#         )
 
         self.statements.extend(
             (
@@ -336,6 +350,14 @@ class %(schema_name)s_instance_factory : public IfcParse::instance_factory {
             % locals()
         )
 
+        ""
+        self.statements[self.statements.index("{string_pool_placeholder}")] = (
+            """
+const std::string strings[] = {%s};
+"""
+            % ",".join(map(lambda s: '"%s"s' % s, self.strings))
+        )
+
     def __str__(self):
         return "\n".join(self.statements)
 
@@ -352,6 +374,23 @@ class SchemaClass(codegen.Base):
 
         x = code(schema_name)
 
+        def transform_to_indexed(fn):
+            def wrapper(*args, **kwargs):
+                declared_type = fn(*args, **kwargs)
+                if 'simple_type' in declared_type:
+                    pass
+                else:
+                    match = re.search(r'\((\w+?_[\w+]+?_\w+?)\)', declared_type)
+                    if match:
+                        old_decl = match.group(1)
+                        tn = old_decl.rsplit('_', 2)[1]
+                        idx = x.names.index(tn)
+                        snu = schema_name.upper()
+                        declared_type = declared_type.replace(old_decl, '%(snu)s_types[%(idx)d]' % locals())
+                return declared_type
+            return wrapper if code == EarlyBoundCodeWriter else fn
+
+        @transform_to_indexed
         def get_declared_type(type, emitted_names=None):
             if isinstance(type, nodes.SimpleType):
                 type = type.type
@@ -469,9 +508,8 @@ class SchemaClass(codegen.Base):
                 if write(name):
                     emitted.add(name.lower())
                     declarations_by_index.append(name)
-                    declared_types.append("%(schema_name)s_%(name)s_type" % locals())
 
-        num_declarations = len(declared_types)
+        num_declarations = len(emitted)
 
         for name, type in mapping.schema.entities.items():
             derived = set(mapping.derived_in_supertype(type))

src/ifcopenshell-python/ifcopenshell/express/templates.py

@@ -124,19 +124,18 @@ simpletype_impl_argument_type = 'if (i == 0) { return %(attr_type)s; } else { th
 simpletype_impl_argument = "return data_->getArgument(i);"
 simpletype_impl_is_with_supertype = "return v == %(class_name)s_type || %(superclass)s::is(v);"
 simpletype_impl_is_without_supertype = "return v == %(class_name)s_type;"
-simpletype_impl_type = "return *%(schema_name_upper)s_%(class_name)s_type;"
-simpletype_impl_class = "return *%(schema_name_upper)s_%(class_name)s_type;"
+simpletype_impl_type = "return *((IfcParse::type_declaration*)%(schema_name_upper)s_types[%(index_in_schema)d]);"
+simpletype_impl_class = "return *((IfcParse::type_declaration*)%(schema_name_upper)s_types[%(index_in_schema)d]);"
 simpletype_impl_explicit_constructor = "data_ = e;"
 simpletype_impl_constructor = (
-    "data_ = new IfcEntityInstanceData(%(schema_name_upper)s_%(class_name)s_type); {IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument(); attr->set(v"
-    + "); data_->setArgument(0, attr);}"
+    "data_ = new IfcEntityInstanceData(%(schema_name_upper)s_types[%(index_in_schema)d]); set_value(0, v);"
 )
-simpletype_impl_constructor_templated = "data_ = new IfcEntityInstanceData(%(schema_name_upper)s_%(class_name)s_type); {IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument(); attr->set(v->generalize()); data_->setArgument(0, attr);}"
+simpletype_impl_constructor_templated = "data_ = new IfcEntityInstanceData(%(schema_name_upper)s_types[%(index_in_schema)d]); set_value(0, v->generalize());"
 simpletype_impl_cast = "return *data_->getArgument(0);"
 simpletype_impl_cast_templated = (
     "aggregate_of_instance::ptr es = *data_->getArgument(0); return es->as< %(underlying_type)s >();"
 )
-simpletype_impl_declaration = "return *%(schema_name_upper)s_%(class_name)s_type;"
+simpletype_impl_declaration = "return *((IfcParse::type_declaration*)%(schema_name_upper)s_types[%(index_in_schema)d]);"
 
 select = """%(documentation)s
 class IFC_PARSE_API %(name)s : public virtual IfcUtil::IfcBaseInterface {
@@ -174,40 +173,33 @@ public:
 """
 
 select_function = """
-const IfcParse::select_type& %(schema_name)s::%(name)s::Class() { return *%(schema_name_upper)s_%(name)s_type; }
+const IfcParse::select_type& %(schema_name)s::%(name)s::Class() { return *((IfcParse::select_type*)%(schema_name_upper)s_types[%(index_in_schema)d]); }
 """
 
 enumeration_function = """
-const IfcParse::enumeration_type& %(schema_name)s::%(name)s::declaration() const { return *%(schema_name_upper)s_%(name)s_type; }
-const IfcParse::enumeration_type& %(schema_name)s::%(name)s::Class() { return *%(schema_name_upper)s_%(name)s_type; }
+const IfcParse::enumeration_type& %(schema_name)s::%(name)s::declaration() const { return *((IfcParse::enumeration_type*)%(schema_name_upper)s_types[%(index_in_schema)d]); }
+const IfcParse::enumeration_type& %(schema_name)s::%(name)s::Class() { return *((IfcParse::enumeration_type*)%(schema_name_upper)s_types[%(index_in_schema)d]); }
 
 %(schema_name)s::%(name)s::%(name)s(IfcEntityInstanceData* e) {
     data_ = e;
 }
 
 %(schema_name)s::%(name)s::%(name)s(Value v) {
-    data_ = new IfcEntityInstanceData(%(schema_name_upper)s_%(name)s_type);
-    IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();
-    attr->set(IfcWrite::IfcWriteArgument::EnumerationReference(v,ToString(v)));
-    data_->setArgument(0,attr);
+    data_ = new IfcEntityInstanceData(%(schema_name_upper)s_types[%(index_in_schema)d]);
+    set_value(0, IfcWrite::IfcWriteArgument::EnumerationReference(v,ToString(v)));
 }
 
 %(schema_name)s::%(name)s::%(name)s(const std::string& v) {
-    data_ = new IfcEntityInstanceData(%(schema_name_upper)s_%(name)s_type);
-    IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();
-    attr->set(IfcWrite::IfcWriteArgument::EnumerationReference(FromString(v),ToString(FromString(v))));
-    data_->setArgument(0,attr);
+    data_ = new IfcEntityInstanceData(%(schema_name_upper)s_types[%(index_in_schema)d]);
+    set_value(0, IfcWrite::IfcWriteArgument::EnumerationReference(FromString(v),ToString(FromString(v))));
 }
 
 const char* %(schema_name)s::%(name)s::ToString(Value v) {
-    if ( v < 0 || v >= %(max_id)d ) throw IfcException("Unable to find keyword in schema");
-    const char* names[] = { %(values)s };
-    return names[v];
+    return %(schema_name)s::%(name)s::%(name)s::Class().lookup_enum_value((size_t)v);
 }
 
 %(schema_name)s::%(name)s::Value %(schema_name)s::%(name)s::FromString(const std::string& s) {
-%(from_string_statements)s
-    throw IfcException("Unable to find keyword in schema: " + s);
+    return (%(schema_name)s::%(name)s::Value) %(schema_name)s::%(name)s::%(name)s::Class().lookup_enum_offset(s);
 }
 
 %(schema_name)s::%(name)s::operator %(schema_name)s::%(name)s::Value() const {
@@ -218,10 +210,10 @@ const char* %(schema_name)s::%(name)s::ToString(Value v) {
 entity_implementation = """// Function implementations for %(name)s
 %(attributes)s
 %(inverse)s
-const IfcParse::entity& %(schema_name)s::%(name)s::declaration() const { return *%(schema_name_upper)s_%(name)s_type; }
-const IfcParse::entity& %(schema_name)s::%(name)s::Class() { return *%(schema_name_upper)s_%(name)s_type; }
-%(schema_name)s::%(name)s::%(name)s(IfcEntityInstanceData* e) : %(superclass)s { if (!e) return; if (e->type() != %(schema_name_upper)s_%(name)s_type) throw IfcException("Unable to find keyword in schema"); data_ = e; }
-%(schema_name)s::%(name)s::%(name)s(%(constructor_arguments)s) : %(superclass)s {data_ = new IfcEntityInstanceData(%(schema_name_upper)s_%(name)s_type); %(constructor_implementation)s }
+const IfcParse::entity& %(schema_name)s::%(name)s::declaration() const { return *((IfcParse::entity*)%(schema_name_upper)s_types[%(index_in_schema)d]); }
+const IfcParse::entity& %(schema_name)s::%(name)s::Class() { return *((IfcParse::entity*)%(schema_name_upper)s_types[%(index_in_schema)d]); }
+%(schema_name)s::%(name)s::%(name)s(IfcEntityInstanceData* e) : %(superclass)s { data_ = e; }
+%(schema_name)s::%(name)s::%(name)s(%(constructor_arguments)s) : %(superclass)s {data_ = new IfcEntityInstanceData(%(schema_name_upper)s_types[%(index_in_schema)d]); %(constructor_implementation)s }
 """
 
 optional_attribute_description = "/// Whether the optional attribute %s is defined for this %s"
@@ -257,36 +249,36 @@ get_attr_stmt_entity = "%(null_check)s return ((IfcUtil::IfcBaseClass*)(*data_->
 get_attr_stmt_array = "%(null_check)s aggregate_of_instance::ptr es = *data_->getArgument(%(index)d); return es->as< %(list_instance_type)s >();"
 get_attr_stmt_nested_array = "%(null_check)s aggregate_of_aggregate_of_instance::ptr es = *data_->getArgument(%(index)d); return es->as< %(list_instance_type)s >();"
 
-get_inverse = "return data_->getInverse(%(schema_name_upper)s_%(type)s_type, %(index)d)->as<%(type)s>();"
+get_inverse = "return data_->getInverse(%(schema_name_upper)s_types[%(type_index)d], %(index)d)->as<%(type)s>();"
 
 set_attr_stmt = (
-    "{IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();%(check_optional_set_begin)sattr->set(%(star_if_optional)sv"
-    + ");%(check_optional_set_end)sdata_->setArgument(%(index)d,attr);}"
+    "%(check_optional_set_begin)sset_value(%(index)d, %(star_if_optional)sv);%(check_optional_set_else)sunset_value(%(index)d);%(check_optional_set_end)s"
 )
-set_attr_stmt_enum = "{IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();%(check_optional_set_begin)sattr->set(IfcWrite::IfcWriteArgument::EnumerationReference(%(star_if_optional)sv,%(non_optional_type)s::ToString(%(star_if_optional)sv)));%(check_optional_set_end)sdata_->setArgument(%(index)d,attr);}"
+set_attr_instance = (
+    "%(check_optional_set_begin)sset_value(%(index)d, v->as<IfcUtil::IfcBaseClass>());%(check_optional_set_else)sunset_value(%(index)d);%(check_optional_set_end)s"
+)
+set_attr_stmt_enum =  "%(check_optional_set_begin)sset_value(%(index)d, IfcWrite::IfcWriteArgument::EnumerationReference(%(star_if_optional)sv,%(non_optional_type)s::ToString(%(star_if_optional)sv)));%(check_optional_set_else)sunset_value(%(index)d);%(check_optional_set_end)s"
 set_attr_stmt_array = (
-    "{IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();%(check_optional_set_begin)sattr->set((%(star_if_optional)sv)->generalize()"
-    + ");%(check_optional_set_end)sdata_->setArgument(%(index)d,attr);}"
+    "%(check_optional_set_begin)sset_value(%(index)d, (%(star_if_optional)sv)->generalize());%(check_optional_set_else)sunset_value(%(index)d);%(check_optional_set_end)s"
 )
 
 constructor_stmt = (
-    "{IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();attr->set((%(name)s)"
-    + ");data_->setArgument(%(index)d,attr);}"
+    "set_value(%(index)d, (%(name)s));"
 )
 constructor_stmt_enum = (
-    "{IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();attr->set((IfcWrite::IfcWriteArgument::EnumerationReference(%(name)s,%(type)s::ToString(%(name)s)))"
-    + ");data_->setArgument(%(index)d,attr);}"
+    "set_value(%(index)d, (IfcWrite::IfcWriteArgument::EnumerationReference(%(name)s,%(type)s::ToString(%(name)s))));"
 )
 constructor_stmt_array = (
-    "{IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();attr->set((%(name)s)->generalize()"
-    + ");data_->setArgument(%(index)d,attr);}"
+    "set_value(%(index)d, (%(name)s)->generalize());"
 )
 constructor_stmt_derived = (
-    "{IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument();attr->set(IfcWrite::IfcWriteArgument::Derived()"
-    + ");data_->setArgument(%(index)d,attr);}"
+    ""
+)
+constructor_stmt_instance = (
+    "set_value(%(index)d, %(name)s ? %(name)s->as<IfcUtil::IfcBaseClass>() : (IfcUtil::IfcBaseClass*) nullptr);"
 )
 
-constructor_stmt_optional = " if (%(name)s) {%(stmt)s } else { IfcWrite::IfcWriteArgument* attr = new IfcWrite::IfcWriteArgument(); attr->set(boost::blank()); data_->setArgument(%(index)d, attr); }"
+constructor_stmt_optional = " if (%(name)s) {%(stmt)s }"
 
 inverse_implementation = '    inverse_map[Type::%(type)s].insert(std::make_pair("%(name)s", std::make_pair(Type::%(related_type)s, %(index)d)));'
 

src/ifcopenshell-python/ifcopenshell/file.py

@@ -28,7 +28,7 @@ import numbers
 import zipfile
 import functools
 from pathlib import Path
-from typing import List, Optional
+from typing import Optional, Any
 
 import ifcopenshell.util.element
 import ifcopenshell.util.file
@@ -52,7 +52,7 @@ class Transaction:
         self.batch_delete_ids = set()
         self.batch_inverses = []
 
-    def serialise_entity_instance(self, element):
+    def serialise_entity_instance(self, element: ifcopenshell.entity_instance) -> dict[str, Any]:
         info = element.get_info()
         for key, value in info.items():
             info[key] = self.serialise_value(element, value)
@@ -103,7 +103,7 @@ class Transaction:
                 }
             )
 
-    def store_delete(self, element):
+    def store_delete(self, element: ifcopenshell.entity_instance) -> None:
         inverses = {}
         if self.is_batched:
             if element.id() not in self.batch_delete_ids:
@@ -328,7 +328,7 @@ class file(object):
         """
         eid = kwargs.pop("id", -1)
 
-        e = entity_instance((self.schema_identifier, type), self)
+        e = ifcopenshell_wrapper.make_instance(self.schema_identifier, type)
 
         # Create pairs of {attribute index, attribute value}.
         # Keyword arguments are mapped to their corresponding
@@ -337,7 +337,7 @@ class file(object):
         # @todo we should probably check that values for
         # attributes are not passed as duplicates using
         # both regular arguments and keyword arguments.
-        attrs = list(enumerate(args)) + [(e.wrapped_data.get_argument_index(name), arg) for name, arg in kwargs.items()]
+        attrs = list(enumerate(args)) + [(e.get_argument_index(name), arg) for name, arg in kwargs.items()]
 
         # Don't store these attributes as transactions
         # as the creation it self is already stored with
@@ -353,14 +353,13 @@ class file(object):
         if attrs:
             self.transaction = transaction
 
-        # Once the values are populated add the instance
+        # Once the values are populated move the instance
         # to the file.
-        self.wrapped_data.add(e.wrapped_data, eid)
+        e = self.wrapped_data.add(e, eid)
 
         # The file container now handles the lifetime of
         # this instance. Tell SWIG that it is no longer
         # the owner.
-        e.wrapped_data.this.disown()
 
         if self.transaction:
             self.transaction.store_create(e)
@@ -398,9 +397,9 @@ class file(object):
 
     def __getitem__(self, key):
         if isinstance(key, numbers.Integral):
-            return entity_instance(self.wrapped_data.by_id(key), self)
+            return self.wrapped_data.by_id(key)
         elif isinstance(key, basestring):
-            return entity_instance(self.wrapped_data.by_guid(str(key)), self)
+            return self.wrapped_data.by_guid(str(key))
 
     def by_id(self, id: int) -> ifcopenshell.entity_instance:
         """Return an IFC entity instance filtered by IFC ID.
@@ -441,8 +440,8 @@ class file(object):
 
         if self.transaction:
             max_id = self.wrapped_data.getMaxId()
-        inst.wrapped_data.this.disown()
-        result = entity_instance(self.wrapped_data.add(inst.wrapped_data, -1 if _id is None else _id), self)
+        # inst.wrapped_data.this.disown()
+        result = self.wrapped_data.add(inst, -1 if _id is None else _id)
         if self.transaction:
             added_elements = [e for e in self.traverse(result) if e.id() > max_id]
             [self.transaction.store_create(e) for e in reversed(added_elements)]
@@ -461,8 +460,8 @@ class file(object):
         :rtype: list[ifcopenshell.entity_instance.entity_instance]
         """
         if include_subtypes:
-            return [entity_instance(e, self) for e in self.wrapped_data.by_type(type)]
-        return [entity_instance(e, self) for e in self.wrapped_data.by_type_excl_subtypes(type)]
+            return self.wrapped_data.by_type(type)
+        return self.wrapped_data.by_type_excl_subtypes(type)
 
     def traverse(
         self, inst: ifcopenshell.entity_instance, max_levels=None, breadth_first=False
@@ -486,7 +485,7 @@ class file(object):
         else:
             fn = self.wrapped_data.traverse
 
-        return [entity_instance(e, self) for e in fn(inst.wrapped_data, max_levels)]
+        return fn(inst, max_levels)
 
     def get_inverse(
         self, inst: ifcopenshell.entity_instance, allow_duplicate=False, with_attribute_indices=False
@@ -504,11 +503,11 @@ class file(object):
         if with_attribute_indices and not allow_duplicate:
             raise ValueError("with_attribute_indices requires allow_duplicate to be True")
 
-        inverses = [entity_instance(e, self) for e in self.wrapped_data.get_inverse(inst.wrapped_data)]
+        inverses = self.wrapped_data.get_inverse(inst)
 
         if allow_duplicate:
             if with_attribute_indices:
-                idxs = self.wrapped_data.get_inverse_indices(inst.wrapped_data)
+                idxs = self.wrapped_data.get_inverse_indices(inst)
                 return list(zip(inverses, idxs))
             else:
                 return inverses
@@ -523,7 +522,7 @@ class file(object):
         :returns: The total number of references
         :rtype: int
         """
-        return self.wrapped_data.get_total_inverses(inst.wrapped_data)
+        return self.wrapped_data.get_total_inverses(inst)
 
     def remove(self, inst: ifcopenshell.entity_instance) -> None:
         """Deletes an IFC object in the file.
@@ -538,7 +537,7 @@ class file(object):
         """
         if self.transaction:
             self.transaction.store_delete(inst)
-        return self.wrapped_data.remove(inst.wrapped_data)
+        return self.wrapped_data.remove(inst)
 
     def batch(self):
         """Low-level mechanism to speed up deletion of large subgraphs"""
@@ -605,4 +604,4 @@ class file(object):
 
     @staticmethod
     def from_pointer(v):
-        return file_dict.get(v)()
+        return file_dict.get(v)() if v else None

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

@@ -23,10 +23,10 @@ from typing import Optional
 def get_references(element: ifcopenshell.entity_instance, should_inherit=True) -> set[ifcopenshell.entity_instance]:
     results = set()
     if not element.is_a("IfcRoot"):
-        if hasattr(element, "HasExternalReferences"):
-            return {r.RelatingReference for r in element.HasExternalReferences or []}
-        elif hasattr(element, "HasExternalReference"):  # Seriously, IFC?
-            return {r.RelatingReference for r in element.HasExternalReference or []}
+        if (references := getattr(element, "HasExternalReferences", None)) is not None or (
+            references := getattr(element, "HasExternalReference", None)
+        ) is not None:
+            return {r.RelatingReference for r in references}
     if should_inherit:
         element_type = ifcopenshell.util.element.get_type(element)
         if element_type and element_type != element:

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

@@ -18,20 +18,59 @@
 #
 #
 
-def get_constraints(product):
+import ifcopenshell
+from typing import Union
+
+
+def get_constraints(product: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
+    """
+    Retrieves the constraints assigned to the `product`.
+
+    :param product: The IFC element.
+    :type product: ifcopenshell.entity_instance.entity_instance
+    :return: List of assigned constraints.
+    :rtype: list[ifcopenshell.entity_instance.entity_instance]
+    """
     constraints = []
     for rel in product.HasAssociations or []:
         if rel.is_a("IfcRelAssociatesConstraint"):
             constraints.append(rel.RelatingConstraint)
     return constraints
 
-def get_metrics(constraint):
+
+def get_constrained_elements(constraint: ifcopenshell.entity_instance) -> set[ifcopenshell.entity_instance]:
+    """
+    Retrieves the elements constrained by a `constraint`.
+
+    :param product: The IFC element.
+    :type product: ifcopenshell.entity_instance.entity_instance
+    :return: Set of elements constrained by a `constrant`.
+    :rtype: set[ifcopenshell.entity_instance.entity_instance]
+    """
+    elements = set()
+    for rel in constraint.file.get_inverse(constraint):
+        if rel.is_a("IfcRelAssociatesConstraint"):
+            elements.update(rel.RelatedObjects)
+    return elements
+
+
+def get_metrics(constraint: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
+    """
+    Retrieves the list of nested constraints for a IfcObjective `constraint`.
+
+    :param product: IfcObjective constraint.
+    :type product: ifcopenshell.entity_instance.entity_instance
+    :return: List of nested constraints.
+    :rtype: list[ifcopenshell.entity_instance.entity_instance]
+    """
+
     metrics = []
     for metric in constraint.BenchmarkValues or []:
         metrics.append(metric)
     return metrics
 
-def get_metric_reference(metric, is_deep=True):
+
+def get_metric_reference(metric: ifcopenshell.entity_instance, is_deep=True):
     def get_reference_Attribute(ref, path):
         if ref:
             if is_deep:
@@ -47,7 +86,10 @@ def get_metric_reference(metric, is_deep=True):
     reference = metric.ReferencePath
     return get_reference_Attribute(reference, "")
 
-def get_metric_constraints(resource, attribute):
+
+def get_metric_constraints(
+    resource: ifcopenshell.entity_instance, attribute
+) -> Union[list[ifcopenshell.entity_instance], None]:
     metrics = []
     for constraint in get_constraints(resource) or []:
         for metric in get_metrics(constraint) or []:
@@ -60,15 +102,14 @@ def get_metric_constraints(resource, attribute):
         return metrics
     return None
 
-def is_hard_constraint(metric):
-    if metric.ConstraintGrade == "HARD" and metric.Benchmark == "EQUALTO":
-        return True
 
-def is_attribute_locked(product, attribute):
+def is_hard_constraint(metric: ifcopenshell.entity_instance) -> bool:
+    return metric.ConstraintGrade == "HARD" and metric.Benchmark == "EQUALTO"
+
+
+def is_attribute_locked(product: ifcopenshell.entity_instance, attribute) -> bool:
     is_locked = False
-    metrics = get_metric_constraints(
-        product, attribute
-    )
+    metrics = get_metric_constraints(product, attribute)
     for metric in metrics or []:
         if is_hard_constraint(metric):
             is_locked = True

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

@@ -20,8 +20,10 @@ import json
 from pathlib import Path
 import copy
 import ifcopenshell
+import ifcopenshell.ifcopenshell_wrapper as ifcopenshell_wrapper
 import ifcopenshell.util.attribute
 import ifcopenshell.util.schema
+from typing import Optional, Literal
 
 try:
     import glob
@@ -58,8 +60,8 @@ IFC4x3_SPEC_URL_TEMPLATE = "https://ifc43-docs.standards.buildingsmart.org/IFC/R
 # child -> description
 # note: in IFC4x3 there is no children[] for properties
 
-
-SCHEMA_FILES = {
+SUPPORTED_SCHEMA = Literal["IFC2X3", "IFC4", "IFC4X3"]
+SCHEMA_FILES: dict[SUPPORTED_SCHEMA, dict] = {
     "IFC2X3": {
         "entities": BASE_MODULE_PATH / "schema/ifc2x3_entities.json",
         "properties": BASE_MODULE_PATH / "schema/ifc2x3_properties.json",
@@ -81,7 +83,11 @@ SCHEMA_FILES = {
 }
 
 db = None
-schema_by_name = {"IFC2X3": None, "IFC4": None, "IFC4X3": None}
+schema_by_name: dict[SUPPORTED_SCHEMA, Optional[ifcopenshell_wrapper.schema_definition]] = {
+    "IFC2X3": None,
+    "IFC4": None,
+    "IFC4X3": None,
+}
 
 
 def get_db(version):
@@ -103,11 +109,12 @@ def get_db(version):
     return db.get(version)
 
 
-def get_schema_by_name(version: str):
+def get_schema_by_name(version: str) -> ifcopenshell_wrapper.schema_definition:
     global schema_by_name
     version = ifcopenshell.util.schema.get_fallback_schema(version)
     if not schema_by_name[version]:
-        schema_by_name[version] = ifcopenshell.ifcopenshell_wrapper.schema_by_name(version)
+        schema_name = "IFC4X3_ADD2" if version == "IFC4X3" else version
+        schema_by_name[version] = ifcopenshell_wrapper.schema_by_name(schema_name)
     return schema_by_name[version]
 
 

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

@@ -20,16 +20,17 @@ from __future__ import annotations
 import ifcopenshell
 import ifcopenshell.util.element
 from typing import Any, Callable, Optional, Union, Literal, overload
+from collections import namedtuple
 
 
 def get_pset(
     element: ifcopenshell.entity_instance,
     name: str,
     prop: Optional[str] = None,
-    psets_only=False,
-    qtos_only=False,
-    should_inherit=True,
-    verbose=False,
+    psets_only: bool = False,
+    qtos_only: bool = False,
+    should_inherit: bool = True,
+    verbose: bool = False,
 ) -> Union[Any, dict[str, Any]]:
     """Retrieve a single property set or single property
 
@@ -429,8 +430,7 @@ def get_predefined_type(element: ifcopenshell.entity_instance) -> str:
         element = ifcopenshell.by_type("IfcWall")[0]
         predefined_type = ifcopenshell.util.element.get_predefined_type(element)
     """
-    element_type = get_type(element)
-    if element_type:
+    if element_type := get_type(element):
         predefined_type = getattr(element_type, "PredefinedType", None)
         if predefined_type == "USERDEFINED" or not predefined_type:
             predefined_type = getattr(element_type, "ElementType", ...)
@@ -563,7 +563,9 @@ def get_material(
             return get_material(relating_type, should_skip_usage)
 
 
-def get_materials(element: ifcopenshell.entity_instance, should_inherit=True) -> list[ifcopenshell.entity_instance]:
+def get_materials(
+    element: ifcopenshell.entity_instance, should_inherit: bool = True
+) -> list[ifcopenshell.entity_instance]:
     """Gets individual materials of an element
 
     If the element has a material set, the individual materials of that set are
@@ -826,7 +828,7 @@ def get_layers(
 
 
 def get_container(
-    element: ifcopenshell.entity_instance, should_get_direct=False, ifc_class: Optional[str] = None
+    element: ifcopenshell.entity_instance, should_get_direct: bool = False, ifc_class: Optional[str] = None
 ) -> ifcopenshell.entity_instance:
     """
     Retrieves the spatial structure container of an element.
@@ -902,6 +904,27 @@ def get_referenced_structures(element: ifcopenshell.entity_instance) -> list[ifc
     return [r.RelatingStructure for r in getattr(element, "ReferencedInStructures", [])]
 
 
+def get_structure_referenced_elements(structure: ifcopenshell.entity_instance) -> set[ifcopenshell.entity_instance]:
+    """Retreives a set of elements referenced by a structure
+
+    :param structure: IfcSpatialElement
+    :type element: ifcopenshell.entity_instance.entity_instance
+    :return: A set of referenced elements, IfcSpatialReferenceSelect
+    :rtype: set[ifcopenshell.entity_instance.entity_instance]
+
+    Example:
+
+    .. code:: python
+
+        element = file.by_type("IfcBuildingStorey")[0]
+        print(ifcopenshell.util.element.get_structure_referenced_elements(element))
+    """
+    referenced = set()
+    for rel in structure.ReferencesElements:
+        referenced.update(rel.RelatedElements)
+    return referenced
+
+
 def get_decomposition(element: ifcopenshell.entity_instance, is_recursive=True) -> list[ifcopenshell.entity_instance]:
     """
     Retrieves all subelements of an element based on the spatial decomposition
@@ -1092,6 +1115,66 @@ def get_components(element: ifcopenshell.entity_instance, include_ports=False) -
             return is_decomposed_by[0].RelatedObjects
 
 
+ReferenceData = namedtuple("ReferenceData", "inverse_attribute, rel_class, relating_element_attribute")
+
+# References below are omitted because they do not introduce
+# any additional referenced objects besides the objects
+# from their supertype IfcExternalReference
+# - IfcExternallyDefinedHatchStyle
+# - IfcExternallyDefinedSurfaceStyle
+# - IfcExternallyDefinedTextFont
+
+REFERENCE_TYPES: dict[str, ReferenceData] = {
+    "IfcClassificationReference": ReferenceData(
+        "ClassificationRefForObjects",
+        "IfcRelAssociatesClassification",
+        "RelatingClassification",
+    ),
+    "IfcDocumentReference": ReferenceData("DocumentRefForObjects", "IfcRelAssociatesDocument", "RelatingDocument"),
+    "IfcLibraryReference": ReferenceData("LibraryRefForObjects", "IfcRelAssociatesLibrary", "RelatingLibrary"),
+}
+
+
+def get_referenced_elements(reference: ifcopenshell.entity_instance) -> set[ifcopenshell.entity_instance]:
+    """Get all elements with assigned `reference`
+
+    :param reference: IfcExternalReference subtype reference
+    :type reference: ifcopenshell.entity_instance.entity_instance
+    :return: The elements with assigned `reference`
+    :rtype: set[ifcopenshell.entity_instance.entity_instance]
+
+    Example:
+
+    .. code:: python
+
+        reference = file.by_type("IfcClassificationReference")[0]
+        elements = ifcopenshell.util.element.get_referenced_elements(reference)
+    """
+
+    related_objects: set[ifcopenshell.entity_instance] = set()
+    ifc_file = reference.file
+    ifc_class = reference.is_a()
+
+    if ifc_file.schema == "IFC2X3":
+        reference_data = REFERENCE_TYPES.get(ifc_class)
+        if reference_data:
+            for rel in ifc_file.by_type(reference_data.rel_class):
+                if getattr(rel, reference_data.relating_element_attribute) == reference:
+                    related_objects.update(rel.RelatedObjects)
+
+    else:
+        # IfcExternalReference
+        for external_rel in reference.ExternalReferenceForResources:
+            related_objects.update(external_rel.RelatedResourceObjects)
+
+        reference_data = REFERENCE_TYPES.get(ifc_class)
+        if reference_data:
+            for rel in getattr(reference, reference_data.inverse_attribute):
+                related_objects.update(rel.RelatedObjects)
+
+    return related_objects
+
+
 def replace_attribute(element: ifcopenshell.entity_instance, old: Any, new: Any) -> None:
     for i, attribute_value in enumerate(element):
         if has_element_reference(attribute_value, old):

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

@@ -61,11 +61,21 @@ def get_axis2placement(placement: ifcopenshell.entity_instance) -> MatrixType:
     :return: A 4x4 numpy matrix
     :rtype: np.ndarray[np.ndarray[float]]
     """
-    if placement.is_a("IfcAxis2Placement3D"):
+    ifc_class = placement.is_a()
+    if ifc_class in ("IfcAxis2Placement3D", "IfcAxis2PlacementLinear"):
         z = np.array(placement.Axis.DirectionRatios if placement.Axis else (0, 0, 1))
         x = np.array(placement.RefDirection.DirectionRatios if placement.RefDirection else (1, 0, 0))
-        o = placement.Location.Coordinates
-    elif placement.is_a("IfcAxis2Placement2D"):
+        location = placement.Location
+        if coordinates := getattr(location, "Coordinates", None):
+            o = coordinates
+        else:
+            import ifcopenshell.geom
+            st = ifcopenshell.geom.settings()
+            st.set('convert-back-units', True)
+            shp = ifcopenshell.geom.create_shape(st, placement)
+            return np.array(shp.matrix).reshape((4, 4), order="F")
+
+    elif ifc_class == "IfcAxis2Placement2D":
         z = np.array((0, 0, 1))
         if placement.RefDirection:
             x = np.array(placement.RefDirection.DirectionRatios)
@@ -73,6 +83,13 @@ def get_axis2placement(placement: ifcopenshell.entity_instance) -> MatrixType:
         else:
             x = np.array((1, 0, 0))
         o = (*placement.Location.Coordinates, 0.0)
+
+    elif ifc_class == "IfcAxis1Placement":
+        axis = placement.Axis
+        z = np.array(axis.DirectionRatios if axis else (0, 0, 1))
+        x = np.array((1, 0, 0))
+        o = placement.Location.Coordinates
+
     return a2p(o, z, x)
 
 
@@ -103,10 +120,10 @@ def get_local_placement(placement: ifcopenshell.entity_instance) -> MatrixType:
     """
     if placement is None:
         return np.eye(4)
-    if placement.PlacementRelTo is None:
+    if (rel_to := placement.PlacementRelTo) is None:
         parent = np.eye(4)
     else:
-        parent = get_local_placement(placement.PlacementRelTo)
+        parent = get_local_placement(rel_to)
     return np.dot(parent, get_axis2placement(placement.RelativePlacement))
 
 

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

@@ -233,7 +233,7 @@ class FormatTransformer(lark.Transformer):
 
     def imperial_length(self, args):
         if len(args) == 2:
-            input_unit = "foot"
+            input_unit, output_unit = "foot", "foot"
             value, precision = args
         else:
             value, precision, input_unit, output_unit = args
@@ -524,7 +524,10 @@ class FacetTransformer(lark.Transformer):
         name = name.children[0].value
 
         def filter_function(element):
-            element_value = getattr(element, name, None)
+            if name == "PredefinedType":
+                element_value = ifcopenshell.util.element.get_predefined_type(element)
+            else:
+                element_value = getattr(element, name, None)
             return self.compare(element_value, comparison, value)
 
         self.elements = set(filter(filter_function, self.elements))