typing

src/bonsai/bonsai/bim/export_ifc.py

@@ -137,7 +137,7 @@ class IfcExporter:
         return checksum != tool.Geometry.get_material_checksum(obj)
 
     def sync_object_placement(self, obj: bpy.types.Object) -> Union[ifcopenshell.entity_instance, None]:
-        element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        element = self.file.by_id(tool.Blender.get_object_bim_props(obj).ifc_definition_id)
         if tool.Geometry.is_scaled(obj):
             bpy.ops.bim.update_representation(obj=obj.name)
             # update_representation might not apply scale if the object has openings

src/bonsai/bonsai/bim/handler.py

@@ -64,14 +64,15 @@ def name_callback(obj: Union[bpy.types.Object, bpy.types.Material], data: str) -
             refresh_ui_data()
         return
 
-    if not obj.BIMObjectProperties.ifc_definition_id:
+    props = tool.Blender.get_object_bim_props(obj)
+    if not props.ifc_definition_id:
         return
 
-    if obj.BIMObjectProperties.is_renaming:
+    if props.is_renaming:
-        obj.BIMObjectProperties.is_renaming = False
+        props.is_renaming = False
         return
 
-    element = tool.Ifc.get().by_id(obj.BIMObjectProperties.ifc_definition_id)
+    element = tool.Ifc.get().by_id(props.ifc_definition_id)
     if "/" in obj.name:
         object_name = obj.name
         element_name = obj.name.split("/", 1)[1]
@@ -87,8 +88,8 @@ def name_callback(obj: Union[bpy.types.Object, bpy.types.Material], data: str) -
     if not element.is_a("IfcRoot"):
         return
     element.Name = element_name
-    if obj.BIMObjectProperties.collection:
+    if props.collection:
-        obj.BIMObjectProperties.collection.name = object_name
+        props.collection.name = object_name
     refresh_ui_data()
 
 

src/bonsai/bonsai/bim/ifc.py

@@ -267,7 +267,8 @@ class IfcStore:
         if element.is_a("IfcSurfaceStyle"):
             obj.BIMStyleProperties.ifc_definition_id = element.id()
         else:
-            obj.BIMObjectProperties.ifc_definition_id = element.id()
+            props = tool.Blender.get_object_bim_props(obj)
+            props.ifc_definition_id = element.id()
 
         tool.Ifc.setup_listeners(obj)
 
@@ -407,7 +408,8 @@ class IfcStore:
         if isinstance(obj, bpy.types.Material):
             obj.BIMStyleProperties.ifc_definition_id = 0
         else:  # bpy.types.Object
-            obj.BIMObjectProperties.ifc_definition_id = 0
+            props = tool.Blender.get_object_bim_props(obj)
+            props.ifc_definition_id = 0
 
     @staticmethod
     def execute_ifc_operator(

src/bonsai/bonsai/bim/import_ifc.py

@@ -933,7 +933,8 @@ class IfcImporter:
         self.project = {"ifc": project}
         obj = tool.Ifc.get_object(project)
         if obj:
-            self.project["blender"] = obj.BIMObjectProperties.collection
+            props = tool.Blender.get_object_bim_props(obj)
+            self.project["blender"] = props.collection
             self.has_existing_project = True
             return
         self.project["blender"] = bpy.data.collections.new(
@@ -943,7 +944,8 @@ class IfcImporter:
         obj.hide_select = True
         self.project["blender"].objects.link(obj)
         self.project["blender"].BIMCollectionProperties.obj = obj
-        obj.BIMObjectProperties.collection = self.collections[project.GlobalId] = self.project["blender"]
+        props = tool.Blender.get_object_bim_props(obj)
+        props.collection = self.collections[project.GlobalId] = self.project["blender"]
 
     def create_styles(self) -> None:
         for style in self.file.by_type("IfcSurfaceStyle"):

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

@@ -34,9 +34,9 @@ class BIM_PT_aggregate(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        props = tool.Blender.get_object_bim_props(obj)
         if not props.ifc_definition_id:
             return False
         if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
@@ -66,9 +66,9 @@ class BIM_PT_aggregate(Panel):
                 col.enabled = False
             op = col.operator("bim.aggregate_assign_object", icon="CHECKMARK")
             if props.relating_object:
-                op.relating_object = props.relating_object.BIMObjectProperties.ifc_definition_id
+                op.relating_object = tool.Blender.get_object_bim_props(props.relating_object).ifc_definition_id
             elif props.related_object:
-                op.related_object = props.related_object.BIMObjectProperties.ifc_definition_id
+                op.related_object = tool.Blender.get_object_bim_props(props.related_object).ifc_definition_id
             row.operator("bim.disable_editing_aggregate", icon="CANCEL", text="")
             return
         else:
@@ -115,9 +115,9 @@ class BIM_PT_linked_aggregate(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        props = tool.Blender.get_object_bim_props(obj)
         if not props.ifc_definition_id:
             return False
         if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):

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

@@ -316,7 +316,8 @@ class ColourByRelatedBuildingElement(bpy.types.Operator):
 
     def _execute(self, context):
         for obj in context.visible_objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            props = tool.Blender.get_object_bim_props(obj)
+            if not props.ifc_definition_id:
                 continue
             element = tool.Ifc.get_entity(obj)
             if not element.is_a("IfcRelSpaceBoundary"):

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

@@ -52,9 +52,9 @@ class BIM_PT_Boundary(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        props = tool.Blender.get_object_bim_props(obj)
         if not props.ifc_definition_id:
             return False
         if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
@@ -65,7 +65,7 @@ class BIM_PT_Boundary(Panel):
     def draw(self, context):
         obj = context.active_object
         assert obj
-        props = obj.BIMObjectProperties
+        props = tool.Blender.get_object_bim_props(obj)
         ifc_file = tool.Ifc.get()
         boundary = ifc_file.by_id(props.ifc_definition_id)
         self.bprops = tool.Boundary.get_object_boundary_props(obj)
@@ -128,9 +128,9 @@ class BIM_PT_SpaceBoundaries(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        props = tool.Blender.get_object_bim_props(obj)
         if not props.ifc_definition_id:
             return False
         if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
@@ -145,7 +145,9 @@ class BIM_PT_SpaceBoundaries(Panel):
         if not SpaceBoundariesData.is_loaded:
             SpaceBoundariesData.load()
 
-        self.props = context.active_object.BIMObjectProperties
+        obj = context.active_object
+        assert obj
+        self.props = tool.Blender.get_object_bim_props(obj)
         self.ifc_file = tool.Ifc.get()
         row = self.layout.row()
         row.operator("bim.load_space_boundaries")

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

@@ -20,6 +20,7 @@ import bpy
 from bonsai.bim.module.model.data import AuthoringData
 from bpy.types import PropertyGroup
 from math import pi
+from typing import TYPE_CHECKING
 
 
 class BIMCadProperties(PropertyGroup):
@@ -31,3 +32,11 @@ class BIMCadProperties(PropertyGroup):
     gable_roof_edge_angle: bpy.props.FloatProperty(
         name="Gable Roof Edge Angle", default=pi / 2, soft_min=0, soft_max=pi / 2, subtype="ANGLE"
     )
+
+    if TYPE_CHECKING:
+        resolution: int
+        radius: float
+        distance: float
+        x: float
+        y: float
+        gable_roof_edge_angle: float

src/bonsai/bonsai/bim/module/cad/workspace.py

@@ -146,7 +146,7 @@ class CadTool(WorkSpaceTool):
             if (
                 (RailingData.is_loaded or not RailingData.load())
                 and RailingData.data["pset_data"]
-                and obj.BIMRailingProperties.is_editing_path
+                and tool.Model.get_railing_props(obj).is_editing_path
             ):
                 add_header_apply_button(
                     layout,
@@ -159,7 +159,7 @@ class CadTool(WorkSpaceTool):
             elif (
                 (RoofData.is_loaded or not RoofData.load())
                 and RoofData.data["pset_data"]
-                and obj.BIMRoofProperties.is_editing_path
+                and tool.Model.get_roof_props(obj).is_editing_path
             ):
                 add_header_apply_button(
                     layout, "Edit Roof Path", "bim.finish_editing_roof_path", "bim.cancel_editing_roof_path", ui_context
@@ -195,12 +195,14 @@ class CadHotkey(bpy.types.Operator):
         return operator.description or ""
 
     def execute(self, context):
-        self.props = context.scene.BIMCadProperties
+        self.props = tool.Cad.get_cad_props()
         getattr(self, f"hotkey_{self.hotkey}")()
         return {"FINISHED"}
 
     def draw(self, context):
-        props = context.scene.BIMCadProperties
+        props = tool.Cad.get_cad_props()
+        obj = context.active_object
+
         if self.hotkey == "S_C":
             if tool.Geometry.is_profile_object_active():
                 row = self.layout.row()
@@ -226,7 +228,7 @@ class CadHotkey(bpy.types.Operator):
             elif (
                 (RoofData.is_loaded or not RoofData.load())
                 and RoofData.data["pset_data"]
-                and bpy.context.active_object.BIMRoofProperties.is_editing_path
+                and tool.Model.get_roof_props(obj).is_editing_path
             ):
                 self.layout.row().prop(props, "gable_roof_edge_angle")
 
@@ -281,13 +283,17 @@ class CadHotkey(bpy.types.Operator):
             bpy.ops.bim.edit_extrusion_axis()
 
     def hotkey_S_R(self):
+        obj = bpy.context.active_object
+        if not obj:
+            return
+
         if tool.Geometry.is_profile_object_active():
             si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
             bpy.ops.bim.add_rectangle(x=self.props.x / si_conversion, y=self.props.y / si_conversion)
         elif (
             (RoofData.is_loaded or not RoofData.load())
             and RoofData.data["pset_data"]
-            and bpy.context.active_object.BIMRoofProperties.is_editing_path
+            and tool.Model.get_roof_props(obj).is_editing_path
         ):
             bpy.ops.bim.set_gable_roof_edge_angle(angle=self.props.gable_roof_edge_angle)
 

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

@@ -316,7 +316,8 @@ class SelectIfcClashResults(bpy.types.Operator):
                 global_ids.extend([clash["a_global_id"], clash["b_global_id"]])
 
         for obj in context.visible_objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            props = tool.Blender.get_object_bim_props(obj)
+            if not props.ifc_definition_id:
                 continue
 
             ifc_file = ""
@@ -335,7 +336,7 @@ class SelectIfcClashResults(bpy.types.Operator):
                 element_file = self.file
 
             try:
-                element = element_file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+                element = element_file.by_id(props.ifc_definition_id)
             except:
                 continue
 

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

@@ -161,8 +161,12 @@ class AssignConstraint(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         self.file = tool.Ifc.get()
-        objs = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
+        objs = [bpy.data.objects[self.obj]] if self.obj else context.selected_objects
-        products = [self.file.by_id(obj_id) for obj in objs if (obj_id := obj.BIMObjectProperties.ifc_definition_id)]
+        products = [
+            self.file.by_id(obj_id)
+            for obj in objs
+            if (obj_id := tool.Blender.get_object_bim_props(obj).ifc_definition_id)
+        ]
         if products:
             ifcopenshell.api.run(
                 "constraint.assign_constraint",
@@ -184,8 +188,12 @@ class UnassignConstraint(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         self.file = tool.Ifc.get()
-        objs = [bpy.data.objects.get(self.obj)] if self.obj else context.selected_objects
+        objs = [bpy.data.objects[self.obj]] if self.obj else context.selected_objects
-        products = [self.file.by_id(obj_id) for obj in objs if (obj_id := obj.BIMObjectProperties.ifc_definition_id)]
+        products = [
+            self.file.by_id(obj_id)
+            for obj in objs
+            if (obj_id := tool.Blender.get_object_bim_props(obj).ifc_definition_id)
+        ]
         if products:
             ifcopenshell.api.run(
                 "constraint.unassign_constraint",

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

@@ -79,18 +79,18 @@ class BIM_PT_object_constraints(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        if not tool.Ifc.get_object_by_identifier(context.active_object.BIMObjectProperties.ifc_definition_id):
+        props = tool.Blender.get_object_bim_props(obj)
-            return False
+        return bool(tool.Ifc.get_object_by_identifier(props.ifc_definition_id))
-        return bool(context.active_object.BIMObjectProperties.ifc_definition_id)
 
     def draw(self, context):
         if not ObjectConstraintsData.is_loaded:
             ObjectConstraintsData.load()
 
         obj = context.active_object
-        self.oprops = obj.BIMObjectProperties
+        assert obj
+        self.oprops = tool.Blender.get_object_bim_props(obj)
         self.sprops = context.scene.BIMConstraintProperties
         self.props = obj.BIMObjectConstraintProperties
         self.file = tool.Ifc.get()

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

@@ -740,15 +740,14 @@ class LoadProductCostItems(bpy.types.Operator):
 
     @classmethod
     def poll(cls, context):
-        if not tool.Ifc.get() or not (obj := context.active_object) or not (obj.BIMObjectProperties.ifc_definition_id):
+        if not tool.Ifc.get() or not (obj := context.active_object) or not (tool.Blender.get_ifc_definition_id(obj)):
             cls.poll_message_set("No IFC object is active.")
             return False
         return True
 
     def execute(self, context):
-        core.load_product_cost_items(
+        obj = context.active_object
-            tool.Cost, product=tool.Ifc.get().by_id(context.active_object.BIMObjectProperties.ifc_definition_id)
+        core.load_product_cost_items(tool.Cost, product=tool.Ifc.get_entity(obj))
-        )
         return {"FINISHED"}
 
 

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

@@ -18,9 +18,13 @@
 
 import bpy
 from bpy.types import PropertyGroup
+from typing import TYPE_CHECKING
 
 
 class BIMCoveringProperties(PropertyGroup):
     ceiling_height: bpy.props.FloatProperty(
         name="ceiling_height", default=2.7, subtype="DISTANCE", description="Ceiling height"
     )
+
+    if TYPE_CHECKING:
+        ceiling_height: float

src/bonsai/bonsai/bim/module/covering/workspace.py

@@ -55,7 +55,7 @@ class CoveringToolUI:
     def draw(cls, context, layout, ifc_element_type=None):
         cls.layout = layout
         cls.props = tool.Model.get_model_props()
-        cls.covering_props = context.scene.BIMCoveringProperties
+        cls.covering_props = tool.Covering.get_covering_props()
 
         row = cls.layout.row(align=True)
         if not tool.Ifc.get():
@@ -159,12 +159,11 @@ class Hotkey(bpy.types.Operator, tool.Ifc.Operator):
         return operator.description or ""
 
     def _execute(self, context):
-        #        self.props = context.scene.BIMCoveringProperties
+        self.props = tool.Covering.get_covering_props()
         getattr(self, f"hotkey_{self.hotkey}")()
 
     def invoke(self, context, event):
         # https://blender.stackexchange.com/questions/276035/how-do-i-make-operators-remember-their-property-values-when-called-from-a-hotkey
-        # self.props = context.scene.BIMSpatialProperties
         return self.execute(context)
 
     def draw(self, context):

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

@@ -181,12 +181,12 @@ class RunAnalysis(bpy.types.Operator):
             if modifier.type == "TRIANGULATE":
                 return True
 
-    def get_covetool_category(self, obj):
+    def get_covetool_category(self, obj: bpy.types.Object):
         if not hasattr(obj, "data") or not isinstance(obj.data, bpy.types.Mesh):
             return
-        if not obj.BIMObjectProperties.ifc_definition_id:
+        if not (ifc_id := tool.Blender.get_ifc_definition_id(obj)):
             return
-        element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        element = self.file.by_id(ifc_id)
         ifc_class = element.is_a()
         if "IfcSlab" in ifc_class:
             return "floors"

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

@@ -382,7 +382,7 @@ class InspectFromObject(bpy.types.Operator):
     def get_active_object_ifc_definition(cls, context: bpy.types.Context) -> Union[int, None]:
         obj = context.active_object
         assert obj
-        if ifc_id := obj.BIMObjectProperties.ifc_definition_id:
+        if ifc_id := tool.Blender.get_ifc_definition_id(obj):
             return ifc_id
         if (
             (data := obj.data)

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

@@ -65,7 +65,7 @@ class VisualiseDiff(bpy.types.Operator):
                 obj.color = (0.0, 0.0, 0.7, 1.0)
                 continue
 
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            if not (ifc_id := tool.Blender.get_ifc_definition_id(obj)):
                 continue
 
             ifc_file = ""
@@ -84,7 +84,7 @@ class VisualiseDiff(bpy.types.Operator):
                 element_file = ifc_file
 
             try:
-                element = element_file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+                element = element_file.by_id(ifc_id)
             except:
                 continue
             global_id = getattr(element, "GlobalId", None)
@@ -253,7 +253,7 @@ class SelectDiffObjects(bpy.types.Operator):
                 obj.select_set(True)
                 continue
 
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            if not (ifc_id := tool.Blender.get_ifc_definition_id(obj)):
                 continue
 
             ifc_file = ""
@@ -272,7 +272,7 @@ class SelectDiffObjects(bpy.types.Operator):
                 element_file = ifc_file
 
             try:
-                element = element_file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+                element = element_file.by_id(ifc_id)
             except:
                 continue
             global_id = getattr(element, "GlobalId", None)

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

@@ -90,18 +90,20 @@ class BIM_PT_object_documents(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        if not tool.Ifc.get_object_by_identifier(context.active_object.BIMObjectProperties.ifc_definition_id):
+        if not (ifc_id := tool.Blender.get_ifc_definition_id(obj)):
             return False
-        return bool(context.active_object.BIMObjectProperties.ifc_definition_id)
+        if not tool.Ifc.get_object_by_identifier(ifc_id):
+            return False
+        return True
 
     def draw(self, context):
         if not ObjectDocumentData.is_loaded:
             ObjectDocumentData.load()
 
         obj = context.active_object
-        self.oprops = obj.BIMObjectProperties
+        self.oprops = tool.Blender.get_object_bim_props(obj)
         self.props = tool.Document.get_document_props()
         self.file = tool.Ifc.get()
 

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

@@ -51,7 +51,7 @@ class Annotator:
         curve.font = font
         props = tool.Drawing.get_text_props(obj)
         props.font_size = "2.5"
-        collection = bpy.context.scene.camera.BIMObjectProperties.collection
+        collection = tool.Blender.get_object_bim_props(bpy.context.scene.camera).collection
         collection.objects.link(obj)
         Annotator.resize_text(obj)
         return obj
@@ -133,7 +133,7 @@ class Annotator:
         co1, _, _, _ = Annotator.get_placeholder_coords(camera)
         matrix_world = tool.Drawing.get_camera_matrix(camera)
         matrix_world.translation = co1
-        collection = camera.BIMObjectProperties.collection
+        collection = tool.Blender.get_object_bim_props(camera).collection
 
         if object_type == "TEXT":
             obj = bpy.data.objects.new(object_type, None)

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

@@ -343,7 +343,7 @@ def get_active_drawing(
     props = tool.Drawing.get_document_props()
     try:
         camera = tool.Ifc.get_object(tool.Ifc.get().by_id(props.active_drawing_id))
-        return camera.BIMObjectProperties.collection, camera
+        return tool.Blender.get_object_bim_props(camera).collection, camera
     except:
         return None, None
 

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

@@ -246,7 +246,7 @@ class CreateDrawing(bpy.types.Operator):
     def execute(self, context):
         self.props = tool.Drawing.get_document_props()
 
-        active_drawing_id = context.scene.camera.BIMObjectProperties.ifc_definition_id
+        active_drawing_id = tool.Blender.get_ifc_definition_id(context.scene.camera)
         if self.print_all:
             original_drawing_id = active_drawing_id
             drawings_to_print = [d.ifc_definition_id for d in self.props.drawings if d.is_selected and d.is_drawing]
@@ -391,7 +391,7 @@ class CreateDrawing(bpy.types.Operator):
             bpy.ops.render.render(write_still=True)
         else:
             previous_visibility = {}
-            for obj in self.camera.BIMObjectProperties.collection.objects:
+            for obj in tool.Blender.get_object_bim_props(self.camera).collection.objects:
                 if bpy.context.view_layer.objects.get(obj.name):
                     previous_visibility[obj.name] = obj.hide_get()
                     obj.hide_set(True)
@@ -2095,7 +2095,7 @@ class ResizeText(bpy.types.Operator):
     # TODO: check undo redo
 
     def execute(self, context):
-        for obj in context.scene.camera.BIMObjectProperties.collection.objects:
+        for obj in tool.Blender.get_object_bim_props(context.scene.camera).collection.objects:
             if isinstance(obj.data, bpy.types.TextCurve):
                 annotation.Annotator.resize_text(obj)
         return {"FINISHED"}

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

@@ -266,7 +266,7 @@ def update_titleblocks(self, context):
 def update_should_draw_decorations(self, context: bpy.types.Context) -> None:
     if self.should_draw_decorations:
         # TODO: design a proper text variable templating renderer
-        collection = context.scene.camera.BIMObjectProperties.collection
+        collection = tool.Blender.get_object_bim_props(context.scene.camera).collection
         for obj in collection.objects:
             element = tool.Ifc.get_entity(obj)
             if not element or not tool.Drawing.is_annotation_object_type(element, ["TEXT", "TEXT_LEADER"]):

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

@@ -102,7 +102,7 @@ def block_scale(scene: bpy.types.Scene) -> None:
     import bonsai.tool as tool
 
     if obj := (getattr(bpy.context, "active_object", None) or bpy.context.view_layer.objects.active):
-        if isinstance(obj, bpy.types.Object) and obj.BIMObjectProperties.ifc_definition_id:
+        if isinstance(obj, bpy.types.Object) and tool.Blender.get_ifc_definition_id(obj):
             if obj.scale != (1, 1, 1):
                 obj.scale = (1, 1, 1)
         elif isinstance(obj, bpy.types.Mesh) and tool.Geometry.get_mesh_props(obj).ifc_definition_id:

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

@@ -464,7 +464,8 @@ class UpdateRepresentation(bpy.types.Operator, tool.Ifc.Operator):
         assert tool.Geometry.is_data_supported_for_adding_representation(data)
         mprops = tool.Geometry.get_mesh_props(data)
 
-        product = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        product = tool.Ifc.get_entity(obj)
+        assert product
         material = ifcopenshell.util.element.get_material(product, should_skip_usage=True)
 
         # NOTE: Currently iterator doesn't detect whether opening is actually affected the representation
@@ -903,7 +904,7 @@ class OverrideOutlinerDelete(bpy.types.Operator):
             if element := tool.Ifc.get_entity(obj):
                 if tool.Geometry.is_locked(element):
                     self.report({"ERROR"}, lock_error_message(obj.name))
-                    if collection := obj.BIMObjectProperties.collection:
+                    if collection := tool.Blender.get_object_bim_props(obj).collection:
                         collections_to_delete.discard(collection)
                     continue
                 tool.Geometry.delete_ifc_object(obj)
@@ -1067,7 +1068,7 @@ class OverrideDuplicateMove(bpy.types.Operator):
                 continue
 
             # clear object's collection so it will be able to have it's own
-            new_obj.BIMObjectProperties.collection = None
+            tool.Blender.get_object_bim_props(new_obj).collection = None
             # copy the actual class
             new = bonsai.core.root.copy_class(tool.Ifc, tool.Collector, tool.Geometry, tool.Root, obj=new_obj)
 

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

@@ -334,9 +334,9 @@ class BIM_PT_connections(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        if not tool.Ifc.get_object_by_identifier(context.active_object.BIMObjectProperties.ifc_definition_id):
+        if not tool.Ifc.get_object_by_identifier(tool.Blender.get_ifc_definition_id(obj)):
             return False
         return tool.Ifc.get()
 
@@ -345,7 +345,6 @@ class BIM_PT_connections(Panel):
             ConnectionsData.load()
 
         layout = self.layout
-        props = context.active_object.BIMObjectProperties
 
         if not ConnectionsData.data["connections"] and not ConnectionsData.data["is_connection_realization"]:
             layout.label(text="No connections found")
@@ -480,12 +479,16 @@ class BIM_PT_placement(Panel):
 
     @classmethod
     def poll(cls, context):
-        return (obj := context.active_object) and obj.BIMObjectProperties.ifc_definition_id
+        return (obj := context.active_object) and tool.Blender.get_ifc_definition_id(obj)
 
     def draw(self, context):
         if not PlacementData.is_loaded:
             PlacementData.load()
 
+        obj = context.active_object
+        assert obj
+        props = tool.Blender.get_object_bim_props(obj)
+
         if not PlacementData.data["has_placement"]:
             row = self.layout.row()
             row.label(text="No Object Placement Found")
@@ -496,12 +499,12 @@ class BIM_PT_placement(Panel):
         row = self.layout.row()
         row.prop(context.active_object, "rotation_euler", text="Rotation")
 
-        if context.active_object.BIMObjectProperties.blender_offset_type != "NONE":
+        if props.blender_offset_type != "NONE":
             row = self.layout.row(align=True)
             row.label(text="Blender Offset", icon="TRACKING_REFINE_FORWARDS")
-            row.label(text=context.active_object.BIMObjectProperties.blender_offset_type)
+            row.label(text=props.blender_offset_type)
 
-            if context.active_object.BIMObjectProperties.blender_offset_type != "NOT_APPLICABLE":
+            if props.blender_offset_type != "NOT_APPLICABLE":
                 row = self.layout.row(align=True)
                 row.label(text=PlacementData.data["original_x"], icon="EMPTY_AXIS")
                 row.label(text=PlacementData.data["original_y"])

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

@@ -91,9 +91,10 @@ class BIM_PT_object_groups(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        return tool.Ifc.get() and context.active_object.BIMObjectProperties.ifc_definition_id
+        props = tool.Blender.get_object_bim_props(obj)
+        return tool.Ifc.get() and props.ifc_definition_id
 
     def draw(self, context):
         if not ObjectGroupsData.is_loaded:

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

@@ -374,16 +374,17 @@ class ObjectLog(bpy.types.Operator):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             cls.poll_message_set("No Active Object")
-        elif not context.active_object.BIMObjectProperties.ifc_definition_id:
+        elif not tool.Blender.get_ifc_definition_id(obj):
             cls.poll_message_set("Active Object doesn't have an IFC definition")
         else:
             return True
 
     def execute(self, context):
-
+        obj = context.active_object
-        step_id = context.active_object.BIMObjectProperties.ifc_definition_id
+        assert obj
+        step_id = tool.Blender.get_ifc_definition_id(obj)
         core.entity_log(tool.IfcGit, tool.Ifc, step_id, self)
         return {"FINISHED"}
 

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

@@ -137,14 +137,14 @@ class BIM_PT_object_material(Panel):
     def poll(cls, context):
         if not tool.Blender.is_tab(context, "GEOMETRY"):
             return False
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not tool.Ifc.get_object_by_identifier(ifc_id):
             return False
-        if not hasattr(tool.Ifc.get().by_id(props.ifc_definition_id), "HasAssociations"):
+        if not hasattr(tool.Ifc.get().by_id(ifc_id), "HasAssociations"):
             return False
         return True
 
@@ -152,9 +152,11 @@ class BIM_PT_object_material(Panel):
         if not ObjectMaterialData.is_loaded:
             ObjectMaterialData.load()
 
+        obj = context.active_object
+        assert obj
         self.file = tool.Ifc.get()
-        self.oprops = context.active_object.BIMObjectProperties
+        self.oprops = tool.Blender.get_object_bim_props(obj)
-        self.props = context.active_object.BIMObjectMaterialProperties
+        self.props = obj.BIMObjectMaterialProperties
         self.mprops = tool.Material.get_material_props()
 
         if not ObjectMaterialData.data["materials"]:

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

@@ -257,7 +257,7 @@ class DrawSystemArrows(bpy.types.Operator, tool.Ifc.Operator):
         sources = []
 
         for obj in bpy.context.selected_objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            if not tool.Blender.get_ifc_definition_id(obj):
                 continue
 
             element = tool.Ifc.get_entity(obj)

src/bonsai/bonsai/bim/module/model/array.py

@@ -72,7 +72,9 @@ class DisableEditingArray(bpy.types.Operator, tool.Ifc.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        context.active_object.BIMArrayProperties.is_editing = -1
+        obj = context.active_object
+        assert obj
+        tool.Model.get_array_props(obj).is_editing = -1
         return {"FINISHED"}
 
 
@@ -84,8 +86,9 @@ class EnableEditingArray(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMArrayProperties
+        props = tool.Model.get_array_props(obj)
 
         relating_obj = props.relating_array_object
 
@@ -119,7 +122,7 @@ class EditArray(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         obj = context.active_object
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMArrayProperties
+        props = tool.Model.get_array_props(obj)
         si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
 
         pset = ifcopenshell.util.element.get_pset(element, "BBIM_Array")
@@ -182,7 +185,7 @@ class RemoveArray(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         obj = context.active_object
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMArrayProperties
+        props = tool.Model.get_array_props(obj)
 
         pset = ifcopenshell.util.element.get_pset(element, "BBIM_Array")
         data = json.loads(pset["Data"])
@@ -302,7 +305,8 @@ class Input3DCursorXArray(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMArrayProperties
+        assert obj
+        props = tool.Model.get_array_props(obj)
         cursor = context.scene.cursor
         if props.use_local_space:
             props.x = (Matrix.inverted(obj.matrix_world) @ cursor.matrix.translation).x
@@ -318,7 +322,8 @@ class Input3DCursorYArray(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMArrayProperties
+        assert obj
+        props = tool.Model.get_array_props(obj)
         cursor = context.scene.cursor
         if props.use_local_space:
             props.y = (Matrix.inverted(obj.matrix_world) @ cursor.matrix.translation).y
@@ -334,7 +339,8 @@ class Input3DCursorZArray(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMArrayProperties
+        assert obj
+        props = tool.Model.get_array_props(obj)
         cursor = context.scene.cursor
         if props.use_local_space:
             props.z = (Matrix.inverted(obj.matrix_world) @ cursor.matrix.translation).z

src/bonsai/bonsai/bim/module/model/data.py

@@ -385,7 +385,9 @@ class StairData:
 
     @classmethod
     def general_params(cls):
-        props = bpy.context.active_object.BIMStairProperties
+        obj = bpy.context.active_object
+        assert obj
+        props = tool.Model.get_stair_props(obj)
         data = cls.data["pset_data"]["data_dict"]
         general_params = {}
         general_props = props.get_props_kwargs(stair_type=data["stair_type"])
@@ -451,7 +453,9 @@ class WindowData:
 
     @classmethod
     def general_params(cls):
-        props = bpy.context.active_object.BIMWindowProperties
+        obj = bpy.context.active_object
+        assert obj
+        props = tool.Model.get_window_props(obj)
         data = cls.data["pset_data"]["data_dict"]
         general_params = {}
         general_props = props.get_general_kwargs()
@@ -462,7 +466,9 @@ class WindowData:
 
     @classmethod
     def lining_params(cls):
-        props = bpy.context.active_object.BIMWindowProperties
+        obj = bpy.context.active_object
+        assert obj
+        props = tool.Model.get_window_props(obj)
         data = cls.data["pset_data"]["data_dict"]
         lining_data = data["lining_properties"]
         lining_params = {}
@@ -474,7 +480,9 @@ class WindowData:
 
     @classmethod
     def panel_params(cls):
-        props = bpy.context.active_object.BIMWindowProperties
+        obj = bpy.context.active_object
+        assert obj
+        props = tool.Model.get_window_props(obj)
         panel_data = cls.data["pset_data"]["data_dict"]["panel_properties"]
         panel_params = {}
         panel_props = props.get_panel_kwargs()
@@ -565,7 +573,9 @@ class RailingData:
 
     @classmethod
     def general_params(cls):
-        props = bpy.context.active_object.BIMRailingProperties
+        obj = bpy.context.active_object
+        assert obj
+        props = tool.Model.get_railing_props(obj)
         data = cls.data["pset_data"]["data_dict"]
         general_params = {}
         general_props = props.get_general_kwargs(railing_type=data["railing_type"])
@@ -599,7 +609,9 @@ class RoofData:
 
     @classmethod
     def general_params(cls):
-        props = bpy.context.active_object.BIMRoofProperties
+        obj = bpy.context.active_object
+        assert obj
+        props = tool.Model.get_roof_props(obj)
         data = cls.data["pset_data"]["data_dict"]
         general_params = {}
         general_props = props.get_general_kwargs(generation_method=data["generation_method"])

src/bonsai/bonsai/bim/module/model/product.py

@@ -718,14 +718,15 @@ class MirrorElements(bpy.types.Operator, tool.Ifc.Operator):
             obj.matrix_world = newmat
 
 
-def generate_box(usecase_path, ifc_file, settings):
+def generate_box(usecase_path: str, ifc_file: ifcopenshell.file, settings: dict[str, Any]) -> None:
     box_context = ifcopenshell.util.representation.get_context(ifc_file, "Model", "Box", "MODEL_VIEW")
     if not box_context:
         return
     obj = settings["blender_object"]
     if 0 in list(obj.dimensions):
         return
-    product = ifc_file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+    product = tool.Ifc.get_entity(obj)
+    assert product
     old_box = ifcopenshell.util.representation.get_representation(product, "Model", "Box", "MODEL_VIEW")
     if settings["context"].ContextType == "Model" and getattr(settings["context"], "ContextIdentifier") == "Body":
         if old_box:

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

@@ -28,34 +28,36 @@ from math import pi, radians
 from bonsai.bim.module.model.decorator import WallAxisDecorator, SlabDirectionDecorator
 from bonsai.bim.module.model.door import update_door_modifier_bmesh
 from bonsai.bim.module.model.window import update_window_modifier_bmesh
-from typing import TYPE_CHECKING, Literal, get_args
+from typing import TYPE_CHECKING, Literal, get_args, Union, get_args
 
 
-def get_ifc_class(self, context):
+def get_ifc_class(self: "BIMModelProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
     if not AuthoringData.is_loaded:
         AuthoringData.load()
     return AuthoringData.data["ifc_classes"]
 
 
-def get_boundary_class(self, context):
+def get_boundary_class(self: "BIMModelProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
     if not AuthoringData.is_loaded:
         AuthoringData.load()
     return AuthoringData.data["boundary_class"]
 
 
-def get_relating_type_id(self, context):
+def get_relating_type_id(self: "BIMModelProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
     if not AuthoringData.is_loaded:
         AuthoringData.load()
     return AuthoringData.data["relating_type_id"]
 
 
-def get_materials(self, context):
+def get_materials(
+    self: Union["BIMWindowProperties", "BIMDoorProperties"], context: bpy.types.Context
+) -> list[tuple[str, str, str]]:
     if not AuthoringData.is_loaded:
         AuthoringData.load()
     return AuthoringData.data["materials"]
 
 
-def update_ifc_class(self, context):
+def update_ifc_class(self: "BIMModelProperties", context: bpy.types.Context) -> None:
     bpy.ops.bim.load_type_thumbnails(ifc_class=self.ifc_class)
     AuthoringData.data["ifc_class_current"] = self.ifc_class
     AuthoringData.data["type_elements"] = AuthoringData.type_elements()
@@ -72,46 +74,46 @@ def update_ifc_class(self, context):
     AuthoringData.data["paginated_relating_types"] = AuthoringData.paginated_relating_types()
 
 
-def update_relating_type_id(self, context):
+def update_relating_type_id(self: "BIMModelProperties", context: bpy.types.Context) -> None:
     AuthoringData.data["relating_type_id"] = AuthoringData.relating_type_id()
     AuthoringData.data["relating_type_data"] = AuthoringData.relating_type_data()
     self.type_page = [e[0] for e in AuthoringData.data["relating_type_id"]].index(self.relating_type_id) // 9 + 1
 
 
-def update_type_page(self, context):
+def update_type_page(self: "BIMModelProperties", context: bpy.types.Context) -> None:
     AuthoringData.data["paginated_relating_types"] = AuthoringData.paginated_relating_types()
     bpy.ops.bim.load_type_thumbnails(ifc_class=self.ifc_class, offset=9 * (self.type_page - 1), limit=9)
     self["type_page"] = min(self["type_page"], AuthoringData.data["total_pages"])
     self["type_page"] = max(self["type_page"], 1)
 
 
-def update_relating_array_from_object(self, context):
+def update_relating_array_from_object(self: "BIMArrayProperties", context: bpy.types.Context) -> None:
     bpy.ops.bim.enable_editing_array(item=self.is_editing)
     return
 
 
-def is_object_array_applicable(self, obj):
+def is_object_array_applicable(self: "BIMArrayProperties", obj: bpy.types.Object) -> bool:
     element = tool.Ifc.get_entity(obj)
     if not element:
         return False
     return ifcopenshell.util.element.get_pset(element, "BBIM_Array")
 
 
-def update_wall_axis_decorator(self, context):
+def update_wall_axis_decorator(self: "BIMModelProperties", context: bpy.types.Context) -> None:
     if self.show_wall_axis:
         WallAxisDecorator.install(bpy.context)
     else:
         WallAxisDecorator.uninstall()
 
 
-def update_slab_direction_decorator(self, context):
+def update_slab_direction_decorator(self: "BIMModelProperties", context: bpy.types.Context) -> None:
     if self.show_slab_direction:
         SlabDirectionDecorator.install(bpy.context)
     else:
         SlabDirectionDecorator.uninstall()
 
 
-def update_search_name(self, context):
+def update_search_name(self: "BIMModelProperties", context: bpy.types.Context) -> None:
     AuthoringData.load()
     # Total number of pages may decrease when using the search bar :
     if self.type_page > AuthoringData.data["total_pages"]:
@@ -119,17 +121,17 @@ def update_search_name(self, context):
     bpy.ops.bim.load_type_thumbnails(ifc_class=self.ifc_class)
 
 
-def update_x_angle(self, context):
+def update_x_angle(self: "BIMModelProperties", context: bpy.types.Context) -> None:
     angle_deg = math.degrees(self.x_angle)
     if tool.Cad.is_x(angle_deg, -90, 0.5) or tool.Cad.is_x(angle_deg, 90, 0.5):
         self.x_angle = 0
 
 
-def update_door(self, context):
+def update_door(self: "BIMDoorProperties", context: bpy.types.Context) -> None:
     update_door_modifier_bmesh(context)
 
 
-def update_window(self, context):
+def update_window(self: "BIMWindowProperties", context: bpy.types.Context) -> None:
     update_window_modifier_bmesh(context)
 
 
@@ -303,36 +305,45 @@ class BIMArrayProperties(PropertyGroup):
         poll=is_object_array_applicable,
     )
 
+    if TYPE_CHECKING:
+        is_editing: int
+        count: int
+        x: float
+        y: float
+        z: float
+        use_local_space: bool
+        method: Literal["OFFSET", "DISTRIBUTE"]
+        sync_children: bool
+        relating_array_object: Union[bpy.types.Object, None]
 
-def update_total_length_target(self, context):
+
+def update_total_length_target(self: "BIMStairProperties", context: bpy.types.Context) -> None:
     self["tread_run"] = self.total_length_target / (self.number_of_treads + 1)
 
 
-def update_tread_run(self, context):
+def update_tread_run(self: "BIMStairProperties", context: bpy.types.Context) -> None:
     if self.total_length_lock:
         self["number_of_treads"] = int((self.total_length_target / self.tread_run) - 1)
     else:
         self["total_length_target"] = (self.number_of_treads + 1) * self.tread_run
 
 
-def update_number_of_treads(self, context):
+def update_number_of_treads(self: "BIMStairProperties", context: bpy.types.Context) -> None:
     if self.total_length_lock:
         self["tread_run"] = self.total_length_target / (self.number_of_treads + 1)
     else:
         self["total_length_target"] = (self.number_of_treads + 1) * self.tread_run
 
 
+StairType = Literal["CONCRETE", "WOOD/STEEL", "GENERIC"]
+
+
 class BIMStairProperties(PropertyGroup):
-    def validate_nosing_value(self, context):
+    def validate_nosing_value(self, context: bpy.types.Context) -> None:
         if self.stair_type != "WOOD/STEEL" and self.nosing_length < 0:
             self["nosing_length"] = 0
 
     non_si_units_props = ("is_editing", "number_of_treads", "has_top_nib", "stair_type")
-    stair_types = (
-        ("CONCRETE", "Concrete", ""),
-        ("WOOD/STEEL", "Wood / Steel", ""),
-        ("GENERIC", "Generic", ""),
-    )
 
     is_editing: bpy.props.BoolProperty(default=False)
     width: bpy.props.FloatProperty(name="Width", default=1.2, soft_min=0.01, subtype="DISTANCE")
@@ -361,7 +372,10 @@ class BIMStairProperties(PropertyGroup):
     top_slab_depth: bpy.props.FloatProperty(name="Top Slab Depth", default=0.25, soft_min=0, subtype="DISTANCE")
     has_top_nib: bpy.props.BoolProperty(name="Has Top Nib", default=True)
     stair_type: bpy.props.EnumProperty(
-        name="Stair Type", items=stair_types, default="CONCRETE", update=validate_nosing_value
+        name="Stair Type",
+        items=[(i, i.replace("/", " / ").title(), "") for i in get_args(StairType)],
+        default="CONCRETE",
+        update=validate_nosing_value,
     )
     custom_first_last_tread_run: bpy.props.FloatVectorProperty(
         name="Custom First / Last Treads Widths",
@@ -385,6 +399,23 @@ class BIMStairProperties(PropertyGroup):
         name="Nosing Depth", description="Depth of the tread's nosing", min=0, default=0, unit="LENGTH"
     )
 
+    if TYPE_CHECKING:
+        is_editing: bool
+        width: float
+        height: float
+        number_of_treads: int
+        total_length_target: float
+        total_length_lock: bool
+        tread_depth: float
+        tread_run: float
+        base_slab_depth: float
+        top_slab_depth: float
+        has_top_nib: bool
+        stair_type: str
+        custom_first_last_tread_run: tuple[float, float]
+        nosing_length: float
+        nosing_depth: float
+
     def get_props_kwargs(self, convert_to_project_units=False, stair_type=None):
         if not stair_type:
             stair_type = self.stair_type
@@ -445,20 +476,22 @@ def window_type_prop_update(self, context):
     update_window(self, context)
 
 
+WindowType = Literal[
+    "SINGLE_PANEL",
+    "DOUBLE_PANEL_HORIZONTAL",
+    "DOUBLE_PANEL_VERTICAL",
+    "TRIPLE_PANEL_BOTTOM",
+    "TRIPLE_PANEL_TOP",
+    "TRIPLE_PANEL_LEFT",
+    "TRIPLE_PANEL_RIGHT",
+    "TRIPLE_PANEL_HORIZONTAL",
+    "TRIPLE_PANEL_VERTICAL",
+]
+
+
 # default prop values are in mm and converted later
 class BIMWindowProperties(PropertyGroup):
     non_si_units_props = ("is_editing", "window_type")
-    window_types = (
-        ("SINGLE_PANEL", "SINGLE_PANEL", ""),
-        ("DOUBLE_PANEL_HORIZONTAL", "DOUBLE_PANEL_HORIZONTAL", ""),
-        ("DOUBLE_PANEL_VERTICAL", "DOUBLE_PANEL_VERTICAL", ""),
-        ("TRIPLE_PANEL_BOTTOM", "TRIPLE_PANEL_BOTTOM", ""),
-        ("TRIPLE_PANEL_TOP", "TRIPLE_PANEL_TOP", ""),
-        ("TRIPLE_PANEL_LEFT", "TRIPLE_PANEL_LEFT", ""),
-        ("TRIPLE_PANEL_RIGHT", "TRIPLE_PANEL_RIGHT", ""),
-        ("TRIPLE_PANEL_HORIZONTAL", "TRIPLE_PANEL_HORIZONTAL", ""),
-        ("TRIPLE_PANEL_VERTICAL", "TRIPLE_PANEL_VERTICAL", ""),
-    )
 
     # number of panels and default mullion/transom values
     # fmt: off
@@ -477,7 +510,10 @@ class BIMWindowProperties(PropertyGroup):
 
     is_editing: bpy.props.BoolProperty(default=False)
     window_type: bpy.props.EnumProperty(
-        name="Window Type", items=window_types, default="SINGLE_PANEL", update=window_type_prop_update
+        name="Window Type",
+        items=[(i, i, "") for i in get_args(WindowType)],
+        default="SINGLE_PANEL",
+        update=window_type_prop_update,
     )
     overall_height: bpy.props.FloatProperty(
         name="Overall Height", default=0.9, subtype="DISTANCE", update=update_window
@@ -546,6 +582,31 @@ class BIMWindowProperties(PropertyGroup):
     framing_material: bpy.props.EnumProperty(name="Framing Material", items=get_materials, options=set())
     glazing_material: bpy.props.EnumProperty(name="Glazing Material", items=get_materials, options=set())
 
+    if TYPE_CHECKING:
+        is_editing: bool
+        window_type: WindowType
+        overall_height: float
+        overall_width: float
+        lining_depth: float
+        lining_thickness: float
+        lining_offset: float
+        lining_to_panel_offset_x: float
+        lining_to_panel_offset_y: float
+        mullion_thickness: float
+        first_mullion_offset: float
+        second_mullion_offset: float
+        first_transom_offset: float
+        second_transom_offset: float
+
+        # Panel properties.
+        frame_depth: tuple[float, float, float]
+        frame_thickness: tuple[float, float, float]
+
+        # Material properties.
+        lining_material: str
+        framing_material: str
+        glazing_material: str
+
     def get_general_kwargs(self, convert_to_project_units=False):
         kwargs = {
             "window_type": self.window_type,
@@ -824,6 +885,10 @@ class BIMDoorProperties(PropertyGroup):
             setattr(self, prop_name, kwargs[prop_name])
 
 
+RailingType = Literal["FRAMELESS_PANEL", "WALL_MOUNTED_HANDRAIL"]
+CapType = Literal["TO_END_POST_AND_FLOOR", "TO_END_POST", "TO_FLOOR", "TO_WALL", "180", "NONE"]
+
+
 class BIMRailingProperties(PropertyGroup):
     non_si_units_props = (
         "is_editing",
@@ -833,23 +898,12 @@ class BIMRailingProperties(PropertyGroup):
         "path_data",
     )
 
-    railing_types = (
-        ("FRAMELESS_PANEL", "FRAMELESS_PANEL", ""),
-        ("WALL_MOUNTED_HANDRAIL", "WALL_MOUNTED_HANDRAIL", ""),
-    )
-    cap_types = (
-        ("TO_END_POST_AND_FLOOR", "TO_END_POST_AND_FLOOR", ""),
-        ("TO_END_POST", "TO_END_POST", ""),
-        ("TO_FLOOR", "TO_FLOOR", ""),
-        ("TO_WALL", "TO_WALL", ""),
-        ("180", "180", ""),
-        ("NONE", "NONE", ""),
-    )
-
     is_editing: bpy.props.BoolProperty(default=False)
     is_editing_path: bpy.props.BoolProperty(default=False)
 
-    railing_type: bpy.props.EnumProperty(name="Railing Type", items=railing_types, default="FRAMELESS_PANEL")
+    railing_type: bpy.props.EnumProperty(
+        name="Railing Type", items=[(i, i, "") for i in get_args(RailingType)], default="FRAMELESS_PANEL"
+    )
     height: bpy.props.FloatProperty(name="Height", default=1.0, subtype="DISTANCE")
     thickness: bpy.props.FloatProperty(name="Thickness", default=0.050, subtype="DISTANCE")
     spacing: bpy.props.FloatProperty(name="Spacing", default=0.050, subtype="DISTANCE")
@@ -875,7 +929,24 @@ class BIMRailingProperties(PropertyGroup):
         description="Clear width between the railing and the wall",
         subtype="DISTANCE",
     )
-    terminal_type: bpy.props.EnumProperty(name="Terminal Type", items=cap_types, default="180")
+    terminal_type: bpy.props.EnumProperty(
+        name="Terminal Type", items=[(i, i, "") for i in get_args(CapType)], default="180"
+    )
+
+    if TYPE_CHECKING:
+        is_editing: bool
+        is_editing_path: bool
+
+        railing_type: RailingType
+        height: float
+        thickness: float
+        spacing: float
+
+        use_manual_supports: bool
+        support_spacing: float
+        railing_diameter: float
+        clear_width: float
+        terminal_type: CapType
 
     def get_general_kwargs(self, railing_type=None, convert_to_project_units=False):
         if railing_type is None:
@@ -921,11 +992,15 @@ def to_percentage(angle: float) -> float:
     return math.tan(angle) * 100
 
 
+RoofType = Literal["HIP/GABLE ROOF"]
+RoofGenerationMethod = Literal["HEIGHT", "ANGLE"]
+
+
 class BIMRoofProperties(PropertyGroup):
-    def update_angle(self, context) -> None:
+    def update_angle(self, context: bpy.types.Context) -> None:
         self["angle"] = to_angle(self.percentage)
 
-    def update_percentage(self, context) -> None:
+    def update_percentage(self, context: bpy.types.Context) -> None:
         self["percentage"] = to_percentage(self.angle)
 
     non_si_units_props = (
@@ -937,18 +1012,15 @@ class BIMRoofProperties(PropertyGroup):
         "percentage",
         "rafter_edge_angle",
     )
-    roof_types = (("HIP/GABLE ROOF", "HIP/GABLE ROOF", ""),)
-    roof_generation_methods = (
-        ("HEIGHT", "HEIGHT", ""),
-        ("ANGLE", "ANGLE", ""),
-    )
 
     is_editing: bpy.props.BoolProperty(default=False)
     is_editing_path: bpy.props.BoolProperty(default=False)
 
-    roof_type: bpy.props.EnumProperty(name="Roof Type", items=roof_types, default="HIP/GABLE ROOF")
+    roof_type: bpy.props.EnumProperty(
+        name="Roof Type", items=[(i, i, "") for i in get_args(RoofType)], default="HIP/GABLE ROOF"
+    )
     generation_method: bpy.props.EnumProperty(
-        name="Roof Generation Method", items=roof_generation_methods, default="ANGLE"
+        name="Roof Generation Method", items=[(i, i, "") for i in get_args(RoofGenerationMethod)], default="ANGLE"
     )
     height: bpy.props.FloatProperty(
         name="Height", default=1.0, description="Maximum height of the roof to be generated.", subtype="DISTANCE"
@@ -978,6 +1050,17 @@ class BIMRoofProperties(PropertyGroup):
         name="Rafter Edge Angle", min=0, max=pi / 2, default=pi / 2, subtype="ANGLE"
     )
 
+    if TYPE_CHECKING:
+        is_editing: bool
+        is_editing_path: bool
+        roof_type: Literal["HIP/GABLE ROOF"]
+        generation_method: Literal["HEIGHT", "ANGLE"]
+        height: float
+        angle: float
+        percentage: float
+        roof_thickness: float
+        rafter_edge_angle: float
+
     def get_general_kwargs(self, generation_method=None, convert_to_project_units=False):
         if generation_method is None:
             generation_method = self.generation_method

src/bonsai/bonsai/bim/module/model/railing.py

@@ -55,8 +55,10 @@ def update_railing_modifier_ifc_data(context: bpy.types.Context) -> None:
     since it's going to update ifc representation
     """
     obj = context.active_object
-    props = obj.BIMRailingProperties
+    assert obj
+    props = tool.Model.get_railing_props(obj)
     element = tool.Ifc.get_entity(obj)
+    assert element
     ifc_file = tool.Ifc.get()
 
     # type attributes
@@ -122,7 +124,8 @@ def update_railing_modifier_bmesh(context: bpy.types.Context) -> None:
     If BBIM Pset just changed should call refresh() before updating bmesh
     """
     obj = context.active_object
-    props = obj.BIMRailingProperties
+    assert obj
+    props = tool.Model.get_railing_props(obj)
     V_ = tool.Blender.V_
 
     # NOTE: using Data since bmesh update will hapen very often
@@ -327,8 +330,10 @@ class AddRailing(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMRailingProperties
+        assert element
+        props = tool.Model.get_railing_props(obj)
         si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
 
         railing_data = props.get_general_kwargs(convert_to_project_units=True)
@@ -367,7 +372,8 @@ class CopyRailingParameters(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         source_obj = context.active_object
-        source_props = source_obj.BIMRailingProperties
+        assert source_obj
+        source_props = tool.Model.get_railing_props(source_obj)
         railing_data = source_props.get_general_kwargs(convert_to_project_units=True)
 
         for target_obj in context.selected_objects:
@@ -379,7 +385,8 @@ class CopyRailingParameters(bpy.types.Operator, tool.Ifc.Operator):
                 continue
             railing_data["path_data"] = RailingData.data["path_data"]
             target_element = tool.Ifc.get_entity(target_obj)
-            target_props = target_obj.BIMRailingProperties
+            assert target_element
+            target_props = tool.Model.get_railing_props(target_obj)
 
             target_props.set_props_kwargs_from_ifc_data(railing_data)
             update_bbim_railing_pset(target_element, railing_data)
@@ -398,7 +405,8 @@ class EnableEditingRailing(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        props = obj.BIMRailingProperties
+        assert obj
+        props = tool.Model.get_railing_props(obj)
         data = tool.Model.get_modeling_bbim_pset_data(obj, "BBIM_Railing")["data_dict"]
         data["path_data"] = json.dumps(data["path_data"])
 
@@ -416,8 +424,9 @@ class CancelEditingRailing(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         data = tool.Model.get_modeling_bbim_pset_data(obj, "BBIM_Railing")["data_dict"]
-        props = obj.BIMRailingProperties
+        props = tool.Model.get_railing_props(obj)
 
         # restore previous settings since editing was canceled
         props.set_props_kwargs_from_ifc_data(data)
@@ -434,8 +443,10 @@ class FinishEditingRailing(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMRailingProperties
+        assert element
+        props = tool.Model.get_railing_props(obj)
 
         pset_data = tool.Model.get_modeling_bbim_pset_data(bpy.context.active_object, "BBIM_Railing")
         path_data = pset_data["data_dict"]["path_data"]
@@ -457,8 +468,10 @@ class FlipRailingPathOrder(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMRailingProperties
+        assert element
+        props = tool.Model.get_railing_props(obj)
 
         pset_data = tool.Model.get_modeling_bbim_pset_data(bpy.context.active_object, "BBIM_Railing")
         path_data = pset_data["data_dict"]["path_data"]
@@ -488,7 +501,8 @@ class EnableEditingRailingPath(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         obj = context.active_object
         [o.select_set(False) for o in context.selected_objects if o != obj]
-        props = obj.BIMRailingProperties
+        assert obj
+        props = tool.Model.get_railing_props(obj)
         data = tool.Model.get_modeling_bbim_pset_data(obj, "BBIM_Railing")["data_dict"]
         # required since we could load pset from .ifc and BIMRoofProperties won't be set
         props.set_props_kwargs_from_ifc_data(data)
@@ -505,7 +519,8 @@ class EnableEditingRailingPath(bpy.types.Operator, tool.Ifc.Operator):
 
 def cancel_editing_railing_path(context: bpy.types.Context) -> set[str]:
     obj = context.active_object
-    props = obj.BIMRailingProperties
+    assert obj
+    props = tool.Model.get_railing_props(obj)
 
     ProfileDecorator.uninstall()
     props.is_editing_path = False
@@ -517,6 +532,7 @@ def cancel_editing_railing_path(context: bpy.types.Context) -> set[str]:
         update_railing_modifier_bmesh(context)
     else:
         element = tool.Ifc.get_entity(obj)
+        assert element
         body = ifcopenshell.util.representation.get_representation(element, "Model", "Body", "MODEL_VIEW")
         bonsai.core.geometry.switch_representation(
             tool.Ifc,
@@ -547,8 +563,9 @@ class FinishEditingRailingPath(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMRailingProperties
+        props = tool.Model.get_railing_props(obj)
 
         railing_data = props.get_general_kwargs(convert_to_project_units=True)
         path_data = get_path_data(obj)
@@ -574,8 +591,11 @@ class RemoveRailing(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        obj.BIMRailingProperties.is_editing = False
+        assert element
+        props = tool.Model.get_railing_props(obj)
+        props.is_editing = False
 
         pset = tool.Pset.get_element_pset(element, "BBIM_Railing")
         ifcopenshell.api.run("pset.remove_pset", tool.Ifc.get(), product=element, pset=pset)

src/bonsai/bonsai/bim/module/model/roof.py

@@ -409,7 +409,8 @@ def update_roof_modifier_ifc_data(context: bpy.types.Context) -> None:
     since it's going to update ifc representation
     """
     obj = context.active_object
-    props = obj.BIMRoofProperties
+    assert obj
+    props = tool.Model.get_roof_props(obj)
     element = tool.Ifc.get_entity(obj)
 
     def roof_is_gabled() -> bool:
@@ -442,7 +443,7 @@ def update_roof_modifier_bmesh(obj: bpy.types.Object) -> None:
     """before using should make sure that Data contains up-to-date information.
     If BBIM Pset just changed should call refresh() before updating bmesh
     """
-    props = obj.BIMRoofProperties
+    props = tool.Model.get_roof_props(obj)
     assert isinstance(obj.data, bpy.types.Mesh)
 
     # NOTE: using Data since bmesh update will hapen very often
@@ -559,7 +560,7 @@ class AddRoof(bpy.types.Operator, tool.Ifc.Operator):
         obj = context.active_object
         assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMRoofProperties
+        props = tool.Model.get_roof_props(obj)
         si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
 
         # rejecting original roof shape to be safe
@@ -607,7 +608,8 @@ class EnableEditingRoof(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        props = obj.BIMRoofProperties
+        assert obj
+        props = tool.Model.get_roof_props(obj)
         data = tool.Model.get_modeling_bbim_pset_data(obj, "BBIM_Roof")["data_dict"]
         # required since we could load pset from .ifc and BIMRoofProperties won't be set
         props.set_props_kwargs_from_ifc_data(data)
@@ -624,7 +626,7 @@ class CancelEditingRoof(bpy.types.Operator, tool.Ifc.Operator):
         obj = context.active_object
         assert obj
         data = tool.Model.get_modeling_bbim_pset_data(obj, "BBIM_Roof")["data_dict"]
-        props = obj.BIMRoofProperties
+        props = tool.Model.get_roof_props(obj)
 
         # restore previous settings since editing was canceled
         props.set_props_kwargs_from_ifc_data(data)
@@ -642,7 +644,7 @@ class FinishEditingRoof(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         obj = context.active_object
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMRoofProperties
+        props = tool.Model.get_roof_props(obj)
 
         pset_data = tool.Model.get_modeling_bbim_pset_data(obj, "BBIM_Roof")
         path_data = pset_data["data_dict"]["path_data"]
@@ -666,7 +668,7 @@ class EnableEditingRoofPath(bpy.types.Operator, tool.Ifc.Operator):
         obj = context.active_object
         assert obj
         [o.select_set(False) for o in context.selected_objects if o != obj]
-        props = obj.BIMRoofProperties
+        props = tool.Model.get_roof_props(obj)
         data = tool.Model.get_modeling_bbim_pset_data(obj, "BBIM_Roof")["data_dict"]
         # required since we could load pset from .ifc and BIMRoofProperties won't be set
         props.set_props_kwargs_from_ifc_data(data)
@@ -720,7 +722,7 @@ class EnableEditingRoofPath(bpy.types.Operator, tool.Ifc.Operator):
 def cancel_editing_roof_path(context: bpy.types.Context) -> set[str]:
     obj = context.active_object
     assert obj
-    props = obj.BIMRoofProperties
+    props = tool.Model.get_roof_props(obj)
 
     ProfileDecorator.uninstall()
     props.is_editing_path = False
@@ -751,7 +753,8 @@ class CopyRoofParameters(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         source_obj = context.active_object
-        source_props = source_obj.BIMRoofProperties
+        assert source_obj
+        source_props = tool.Model.get_roof_props(source_obj)
         data = source_props.get_general_kwargs(convert_to_project_units=True)
 
         for target_obj in context.selected_objects:
@@ -763,7 +766,7 @@ class CopyRoofParameters(bpy.types.Operator, tool.Ifc.Operator):
                 continue
             data["path_data"] = RoofData.data["path_data"]
             target_element = tool.Ifc.get_entity(target_obj)
-            target_props = target_obj.BIMRoofProperties
+            target_props = tool.Model.get_roof_props(target_obj)
 
             target_props.set_props_kwargs_from_ifc_data(data)
             update_bbim_roof_pset(target_element, data)
@@ -783,7 +786,7 @@ class FinishEditingRoofPath(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         obj = context.active_object
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMRoofProperties
+        props = tool.Model.get_roof_props(obj)
 
         bm = tool.Blender.get_bmesh_for_mesh(obj.data)
         op_status, error_message = is_valid_roof_footprint(bm)
@@ -815,9 +818,12 @@ class RemoveRoof(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        obj.BIMRoofProperties.is_editing = False
+        props = tool.Model.get_roof_props(obj)
+        props.is_editing = False
 
+        assert element
         pset = tool.Pset.get_element_pset(element, "BBIM_Roof")
         ifcopenshell.api.run("pset.remove_pset", tool.Ifc.get(), product=element, pset=pset)
         return {"FINISHED"}

src/bonsai/bonsai/bim/module/model/stair.py

@@ -34,7 +34,8 @@ from bpy_extras.object_utils import AddObjectHelper, object_data_add
 
 
 def regenerate_stair_mesh(obj: bpy.types.Object) -> None:
-    props_kwargs = obj.BIMStairProperties.get_props_kwargs()
+    props = tool.Model.get_stair_props(obj)
+    props_kwargs = props.get_props_kwargs()
     vertices, edges, faces = tool.Model.generate_stair_2d_profile(**props_kwargs)
 
     bm = bmesh.new()
@@ -69,7 +70,8 @@ def update_ifc_stair_props(obj: bpy.types.Object) -> None:
     since it's going to update ifc representation
     """
     element = tool.Ifc.get_entity(obj)
-    props = obj.BIMStairProperties
+    assert element
+    props = tool.Model.get_stair_props(obj)
     ifc_file = tool.Ifc.get()
 
     if tool.Ifc.get_schema() != "IFC2X3" and element.is_a("IfcStairFlight"):
@@ -183,7 +185,8 @@ class AddStair(bpy.types.Operator, tool.Ifc.Operator):
         obj = context.active_object
         assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMStairProperties
+        assert element
+        props = tool.Model.get_stair_props(obj)
         ifc_file = tool.Ifc.get()
 
         stair_data = props.get_props_kwargs(convert_to_project_units=True)
@@ -214,9 +217,11 @@ class CancelEditingStair(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
+        assert element
         data = json.loads(ifcopenshell.util.element.get_pset(element, "BBIM_Stair", "Data"))
-        props = obj.BIMStairProperties
+        props = tool.Model.get_stair_props(obj)
         # restore previous settings since editing was canceled
         props.set_props_kwargs_from_ifc_data(data)
         regenerate_stair_mesh(obj)
@@ -233,8 +238,10 @@ class FinishEditingStair(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMStairProperties
+        assert element
+        props = tool.Model.get_stair_props(obj)
 
         data = props.get_props_kwargs(convert_to_project_units=True)
         props.is_editing = False
@@ -257,7 +264,8 @@ class EnableEditingStair(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        props = obj.BIMStairProperties
+        assert obj
+        props = tool.Model.get_stair_props(obj)
         element = tool.Ifc.get_entity(obj)
         data = json.loads(ifcopenshell.util.element.get_pset(element, "BBIM_Stair", "Data"))
         # required since we could load pset from .ifc and BIMStairProperties won't be set
@@ -273,9 +281,11 @@ class RemoveStair(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        props = obj.BIMStairProperties
+        assert obj
+        props = tool.Model.get_stair_props(obj)
         element = tool.Ifc.get_entity(obj)
-        obj.BIMStairProperties.is_editing = False
+        assert element
+        props.is_editing = False
 
         pset = tool.Pset.get_element_pset(element, "BBIM_Stair")
         ifcopenshell.api.run("pset.remove_pset", tool.Ifc.get(), product=element, pset=pset)

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

@@ -217,7 +217,9 @@ class BIM_PT_array(bpy.types.Panel):
         if not ArrayData.is_loaded:
             ArrayData.load()
 
-        props = context.active_object.BIMArrayProperties
+        obj = context.active_object
+        assert obj
+        props = tool.Model.get_array_props(obj)
 
         if ArrayData.data["parameters"]:
             row = self.layout.row(align=True)
@@ -291,7 +293,7 @@ class BIM_PT_stair(bpy.types.Panel):
 
         obj = context.active_object
         assert obj
-        props = obj.BIMStairProperties
+        props = tool.Model.get_stair_props(obj)
 
         if StairData.data["pset_data"]:
             row = self.layout.row(align=True)
@@ -404,7 +406,9 @@ class BIM_PT_window(bpy.types.Panel):
         if not WindowData.is_loaded:
             WindowData.load()
 
-        props = context.active_object.BIMWindowProperties
+        obj = context.active_object
+        assert obj
+        props = tool.Model.get_window_props(obj)
 
         if WindowData.data["pset_data"]:
             row = self.layout.row(align=True)
@@ -594,7 +598,9 @@ class BIM_PT_railing(bpy.types.Panel):
         if not RailingData.is_loaded:
             RailingData.load()
 
-        props = context.active_object.BIMRailingProperties
+        obj = context.active_object
+        assert obj
+        props = tool.Model.get_railing_props(obj)
 
         if RailingData.data["pset_data"]:
             row = self.layout.row(align=True)
@@ -659,7 +665,7 @@ class BIM_PT_roof(bpy.types.Panel):
 
         obj = context.active_object
         assert obj
-        props = obj.BIMRoofProperties
+        props = tool.Model.get_roof_props(obj)
 
         if RoofData.data["pset_data"]:
             row = self.layout.row(align=True)

src/bonsai/bonsai/bim/module/model/window.py

@@ -41,8 +41,10 @@ V_ = tool.Blender.V_
 
 def update_window_modifier_representation(context: bpy.types.Context) -> None:
     obj = context.active_object
+    assert obj
     element = tool.Ifc.get_entity(obj)
-    props = obj.BIMWindowProperties
+    assert element
+    props = tool.Model.get_window_props(obj)
     ifc_file = tool.Ifc.get()
     si_conversion = ifcopenshell.util.unit.calculate_unit_scale(ifc_file)
 
@@ -258,7 +260,8 @@ def create_bm_window(
 
 def update_window_modifier_bmesh(context: bpy.types.Context) -> None:
     obj = context.active_object
-    props = obj.BIMWindowProperties
+    assert obj
+    props = tool.Model.get_window_props(obj)
     panel_schema = DEFAULT_PANEL_SCHEMAS[props.window_type]
     accumulated_height = [0] * len(panel_schema[0])
     built_panels = []
@@ -447,8 +450,10 @@ class AddWindow(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMWindowProperties
+        assert element
+        props = tool.Model.get_window_props(obj)
 
         window_data = props.get_general_kwargs(convert_to_project_units=True)
         lining_props = props.get_lining_kwargs(convert_to_project_units=True)
@@ -477,11 +482,13 @@ class CancelEditingWindow(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
+        assert element
         data = json.loads(ifcopenshell.util.element.get_pset(element, "BBIM_Window", "Data"))
         data.update(data.pop("lining_properties"))
         data.update(data.pop("panel_properties"))
-        props = obj.BIMWindowProperties
+        props = tool.Model.get_window_props(obj)
         props.set_props_kwargs_from_ifc_data(data)
 
         body = ifcopenshell.util.representation.get_representation(element, "Model", "Body", "MODEL_VIEW")
@@ -506,8 +513,10 @@ class FinishEditingWindow(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        props = obj.BIMWindowProperties
+        assert element
+        props = tool.Model.get_window_props(obj)
 
         window_data = props.get_general_kwargs(convert_to_project_units=True)
         lining_props = props.get_lining_kwargs(convert_to_project_units=True)
@@ -533,8 +542,10 @@ class EnableEditingWindow(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        props = obj.BIMWindowProperties
+        assert obj
+        props = tool.Model.get_window_props(obj)
         element = tool.Ifc.get_entity(obj)
+        assert element
         data = json.loads(ifcopenshell.util.element.get_pset(element, "BBIM_Window", "Data"))
         data.update(data.pop("lining_properties"))
         data.update(data.pop("panel_properties"))
@@ -553,9 +564,11 @@ class RemoveWindow(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        props = obj.BIMWindowProperties
+        assert obj
         element = tool.Ifc.get_entity(obj)
-        obj.BIMWindowProperties.is_editing = False
+        assert element
+        props = tool.Model.get_window_props(obj)
+        props.is_editing = False
 
         pset = tool.Pset.get_element_pset(element, "BBIM_Window")
         ifcopenshell.api.run("pset.remove_pset", tool.Ifc.get(), product=element, pset=pset)

src/bonsai/bonsai/bim/module/model/workspace.py

@@ -1046,6 +1046,7 @@ class EditObjectUI:
 
     @classmethod
     def draw_modes(cls, context: bpy.types.Context) -> None:
+        obj = context.active_object
         ui_context = str(context.region.type)
         row = cls.layout.row(align=True)
         row.separator()
@@ -1055,9 +1056,7 @@ class EditObjectUI:
             if len(context.selected_objects) == 1 and AuthoringData.data["has_extrusion"]:
                 row = cls.layout.row(align=True) if ui_context != "TOOL_HEADER" else row
                 add_layout_hotkey_operator(row, "Edit Profile", "S_E", "", ui_context)
-        elif (
+        elif tool.Model.is_parametric_railing_active() and not tool.Model.get_railing_props(obj).is_editing_path:
-            tool.Model.is_parametric_railing_active() and not context.active_object.BIMRailingProperties.is_editing_path
-        ):
             row = cls.layout.row(align=True) if ui_context != "TOOL_HEADER" else row
             row.operator(
                 "bim.enable_editing_railing_path",
@@ -1208,12 +1207,12 @@ class Hotkey(bpy.types.Operator, tool.Ifc.Operator):
         # and it might conflict with one of the conditions below
         if (
             tool.Model.is_parametric_railing_active()
-            and not bpy.context.active_object.BIMRailingProperties.is_editing_path
+            and not tool.Model.get_railing_props(active_object).is_editing_path
         ):
             bpy.ops.bim.enable_editing_railing_path()
             return
 
-        elif tool.Model.is_parametric_roof_active() and not bpy.context.active_object.BIMRoofProperties.is_editing_path:
+        elif tool.Model.is_parametric_roof_active() and not tool.Model.get_roof_props(active_object).is_editing_path:
             # undo the unselection done above because roof has no usage type
             bpy.ops.bim.enable_editing_roof_path()
             return

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

@@ -40,7 +40,7 @@ def update_relating_object(self, context):
 
     if self.relating_object is None:
         return
-    if not self.relating_object.BIMObjectProperties.ifc_definition_id:
+    if not tool.Blender.get_ifc_definition_id(self.relating_object):
         context.window_manager.popup_menu(message, title="Invalid Element Selected", icon="INFO")
         self.relating_object = None
 

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

@@ -32,14 +32,14 @@ class BIM_PT_nest(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not tool.Ifc.get_object_by_identifier(ifc_id):
             return False
-        if not tool.Ifc.get().by_id(props.ifc_definition_id).is_a("IfcObjectDefinition"):
+        if not tool.Ifc.get().by_id(ifc_id).is_a("IfcObjectDefinition"):
             return False
         return True
 
@@ -55,7 +55,7 @@ class BIM_PT_nest(Panel):
             row.prop(props, "relating_object", text="")
             if props.relating_object:
                 op = row.operator("bim.nest_assign_object", icon="CHECKMARK", text="")
-                op.relating_object = props.relating_object.BIMObjectProperties.ifc_definition_id
+                op.relating_object = tool.Blender.get_ifc_definition_id(props.relating_object)
             row.operator("bim.disable_editing_nest", icon="CANCEL", text="")
         else:
             row = layout.row(align=True)

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

@@ -2327,11 +2327,12 @@ class RefreshClippingPlanes(bpy.types.Operator):
             else:
                 break
 
-    def is_moved(self, obj):
+    def is_moved(self, obj: bpy.types.Object) -> bool:
-        if not obj.BIMObjectProperties.location_checksum:
+        props = tool.Blender.get_object_bim_props(obj)
+        if not props.location_checksum:
             return True  # Let's be conservative
-        loc_check = np.frombuffer(eval(obj.BIMObjectProperties.location_checksum))
+        loc_check = np.frombuffer(eval(props.location_checksum))
-        rot_check = np.frombuffer(eval(obj.BIMObjectProperties.rotation_checksum))
+        rot_check = np.frombuffer(eval(props.rotation_checksum))
         loc_real = np.array(obj.matrix_world.translation).flatten()
         rot_real = np.array(obj.matrix_world.to_3x3()).flatten()
         if np.allclose(loc_check, loc_real, atol=1e-4) and np.allclose(rot_check, rot_real, atol=1e-2):

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

@@ -351,10 +351,9 @@ class BIM_OT_add_edit_custom_property(bpy.types.Operator, tool.Ifc.Operator):
         props = context.scene.AddEditProperties
 
         for obj in tool.Blender.get_selected_objects():
-            ifc_definition_id = obj.BIMObjectProperties.ifc_definition_id
+            ifc_element = tool.Ifc.get_entity(obj)
-            if not ifc_definition_id:
+            if not ifc_element:
                 continue
-            ifc_element = tool.Ifc.get().by_id(ifc_definition_id)
 
             for prop in props:
                 value = getattr(prop, prop.get_value_name())
@@ -406,23 +405,19 @@ class BIM_OT_bulk_remove_psets(bpy.types.Operator, tool.Ifc.Operator):
         props = context.scene.DeletePsets
 
         for obj in tool.Blender.get_selected_objects():
-            ifc_definition_id = obj.BIMObjectProperties.ifc_definition_id
+            ifc_element = tool.Ifc.get_entity(obj)
-            if not ifc_definition_id:
+            if not ifc_element:
                 continue
-            ifc_element = tool.Ifc.get().by_id(ifc_definition_id)
             psets = ifcopenshell.util.element.get_psets(ifc_element)
 
             for prop in props:
                 pset = prop.pset_name
                 if pset in psets:
                     try:
-                        ifcopenshell.api.run(
+                        ifcopenshell.api.pset.remove_pset(
-                            "pset.remove_pset",
                             self.file,
-                            **{
+                            product=ifc_element,
-                                "product": self.file.by_id(ifc_definition_id),
+                            pset=self.file.by_id(psets[pset]["id"]),
-                                "pset": self.file.by_id(psets[pset]["id"]),
-                            },
                         )
                     except KeyError:
                         pass  # Sometimes the pset id is not found, I'm not sure why this happens though. - vulevukusej

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

@@ -241,12 +241,12 @@ class BIM_PT_object_psets(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not tool.Ifc.get_object_by_identifier(ifc_id):
             return False
         return True
 
@@ -319,12 +319,12 @@ class BIM_PT_object_qtos(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not tool.Ifc.get_object_by_identifier(ifc_id):
             return False
         return True
 

src/bonsai/bonsai/bim/module/qto/calculator.py

@@ -648,7 +648,8 @@ def get_opening_area(
     """
     total_opening_area = 0
     ifc = tool.Ifc.get()
-    ifc_element = ifc.by_id(obj.BIMObjectProperties.ifc_definition_id)
+    ifc_element = tool.Ifc.get_entity(obj)
+    assert ifc_element
     if len(openings := ifc_element.HasOpenings) != 0:
         for opening in openings:
             opening_id = opening.RelatedOpeningElement.GlobalId
@@ -887,7 +888,7 @@ def get_OBB_object(obj: bpy.types.Object) -> bpy.types.Object:
     :param blender-object obj: Blender Object
     :return blender-object: OBB of the Object
     """
-    ifc_id = obj.BIMObjectProperties.ifc_definition_id
+    ifc_id = tool.Blender.get_ifc_definition_id(obj)
     bbox = obj.bound_box
     # matrix transformation to go from obj coordinates to world coordinates:
     obb = [Vector(v) for v in bbox]
@@ -929,7 +930,7 @@ def get_AABB_object(obj: bpy.types.Object) -> bpy.types.Object:
     :param blender-object obj: Blender Object
     :return blender-object: AABB of the Object
     """
-    ifc_id = obj.BIMObjectProperties.ifc_definition_id
+    ifc_id = tool.Blender.get_ifc_definition_id(obj)
     aabb_mesh = bpy.data.meshes.new(f"OBB_{ifc_id}")
 
     x = [v.co.x for v in obj.data.vertices]
@@ -994,7 +995,7 @@ def get_bisected_obj(
     :param tuple(x,y,z) plane_no_neg: Tuple describing the normal vector of the lower bisection plane. Example: (0,0,-1)
     :return _type_: _description_
     """
-    ifc_id = obj.BIMObjectProperties.ifc_definition_id
+    ifc_id = tool.Blender.get_ifc_definition_id(obj)
 
     bis_obj = obj.copy()
     bis_obj.data = obj.data.copy()

src/bonsai/bonsai/bim/module/qto/helper.py

@@ -18,6 +18,7 @@
 
 import bpy
 import bmesh
+import bonsai.tool as tool
 from typing import Callable
 
 
@@ -86,7 +87,7 @@ def calculate_formwork_area(objs: list[bpy.types.Object], context: bpy.types.Con
                 bpy.ops.object.modifier_apply(modifier="Boolean")
 
     copied_obj.name = "Formwork"
-    copied_obj.BIMObjectProperties.ifc_definition_id = 0
+    tool.Blender.get_object_bim_props(copied_obj).ifc_definition_id = 0
     modifier = copied_obj.modifiers.new("Formwork", "REMESH")
     assert isinstance(modifier, bpy.types.RemeshModifier)
     modifier.mode = "SHARP"

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

@@ -48,7 +48,8 @@ class EnableReassignClass(bpy.types.Operator):
         element = tool.Ifc.get_entity(obj)
         assert element
         ifc_class = element.is_a()
-        context.active_object.BIMObjectProperties.is_reassigning_class = True
+        props = tool.Blender.get_object_bim_props(obj)
+        props.is_reassigning_class = True
         ifc_products = tool.Root.get_ifc_products()
         schema = tool.Ifc.schema()
         declaration = schema.declaration_by_name(ifc_class)
@@ -58,10 +59,10 @@ class EnableReassignClass(bpy.types.Operator):
                 break
         else:
             self.report({"ERROR"}, f"Couldn't find matching IFC product for the selected object: '{element}'.")
-            obj.BIMObjectProperties.is_reassigning_class = False
+            props.is_reassigning_class = False
             return {"CANCELLED"}
 
-        element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        element = self.file.by_id(tool.Blender.get_ifc_definition_id(obj))
         rprops.ifc_class = element.is_a()
         rprops.relating_class_object = None
         if hasattr(element, "PredefinedType"):
@@ -78,7 +79,8 @@ class DisableReassignClass(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        context.active_object.BIMObjectProperties.is_reassigning_class = False
+        props = tool.Blender.get_object_bim_props(context.active_object)
+        props.is_reassigning_class = False
         return {"FINISHED"}
 
 
@@ -127,7 +129,8 @@ class ReassignClass(bpy.types.Operator, tool.Ifc.Operator):
                     )
                     return {"CANCELLED"}
 
-            obj.BIMObjectProperties.is_reassigning_class = False
+            props = tool.Blender.get_object_bim_props(obj)
+            props.is_reassigning_class = False
             if element.is_a("IfcTypeObject"):
                 elements_to_reassign[element] = ifc_class
                 elements_to_update.update(ifcopenshell.util.element.get_types(element))

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

@@ -43,7 +43,9 @@ class BIM_PT_class(Panel):
     def draw(self, context):
         if not IfcClassData.is_loaded:
             IfcClassData.load()
-        props = context.active_object.BIMObjectProperties
+        obj = context.active_object
+        assert obj
+        props = tool.Blender.get_object_bim_props(obj)
         rprops = tool.Root.get_root_props()
         if props.ifc_definition_id:
             if not IfcClassData.data["has_entity"]:

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

@@ -1449,15 +1449,17 @@ class LoadProductTasks(bpy.types.Operator):
 
     @classmethod
     def poll(cls, context):
-        if not tool.Ifc.get() or not (obj := context.active_object) or not (obj.BIMObjectProperties.ifc_definition_id):
+        if not tool.Ifc.get() or not (obj := context.active_object) or not (tool.Blender.get_ifc_definition_id(obj)):
             cls.poll_message_set("No IFC object is active.")
             return False
         return True
 
     def execute(self, context):
-        result = core.load_product_related_tasks(
+        obj = context.active_object
-            tool.Sequence, product=tool.Ifc.get().by_id(context.active_object.BIMObjectProperties.ifc_definition_id)
+        assert obj
-        )
+        product = tool.Ifc.get_entity(obj)
+        assert product
+        result = core.load_product_related_tasks(tool.Sequence, product=product)
         if isinstance(result, str):
             self.report({"INFO"}, result)
         else:

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

@@ -271,10 +271,10 @@ def update_sort_reversed(self, context):
 
 
 def update_filter_by_active_schedule(self, context):
-    if context.active_object:
+    if obj := context.active_object:
-        core.load_product_related_tasks(
+        product = tool.Ifc.get_entity(obj)
-            tool.Sequence, product=tool.Ifc.get().by_id(context.active_object.BIMObjectProperties.ifc_definition_id)
+        assert product
-        )
+        core.load_product_related_tasks(tool.Sequence, product=product)
 
 
 def switch_options(self, context):

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

@@ -75,11 +75,13 @@ class AddStructuralMemberConnection(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        oprops = obj.BIMObjectProperties
+        assert obj
+        oprops = tool.Blender.get_object_bim_props(obj)
         props = obj.BIMStructuralProperties
         file = tool.Ifc.get()
         related_structural_connection = file.by_id(oprops.ifc_definition_id)
-        relating_structural_member = file.by_id(props.relating_structural_member.BIMObjectProperties.ifc_definition_id)
+        relating_structural_member = tool.Ifc.get_entity(props.relating_structural_member)
+        assert relating_structural_member
         if not relating_structural_member.is_a("IfcStructuralMember"):
             return {"FINISHED"}
         ifcopenshell.api.structural.add_structural_member_connection(
@@ -99,7 +101,6 @@ class EnableEditingStructuralConnectionCondition(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        oprops = obj.BIMObjectProperties
         props = obj.BIMStructuralProperties
         props.active_connects_structural_member = self.connects_structural_member
         return {"FINISHED"}
@@ -350,7 +351,8 @@ class EnableEditingStructuralItemAxis(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        oprops = obj.BIMObjectProperties
+        assert obj
+        oprops = tool.Blender.get_object_bim_props(obj)
         props = obj.BIMStructuralProperties
 
         self.file = tool.Ifc.get()
@@ -403,7 +405,8 @@ class EditStructuralItemAxis(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        oprops = obj.BIMObjectProperties
+        assert obj
+        oprops = tool.Blender.get_object_bim_props(obj)
         props = obj.BIMStructuralProperties
         relative_matrix = props.axis_empty.matrix_world @ obj.matrix_world.inverted()
         z_axis = relative_matrix.col[2][0:3]
@@ -425,11 +428,12 @@ class EnableEditingStructuralConnectionCS(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        oprops = obj.BIMObjectProperties
+        assert obj
         props = obj.BIMStructuralProperties
 
         self.file = tool.Ifc.get()
-        item = self.file.by_id(oprops.ifc_definition_id)
+        item = tool.Ifc.get_entity(obj)
+        assert item
 
         location = obj.data.vertices[0].co
         empty = bpy.data.objects.new("Item Connection CS", None)
@@ -491,16 +495,17 @@ class EditStructuralConnectionCS(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        oprops = obj.BIMObjectProperties
+        assert obj
+        item = tool.Ifc.get_entity(obj)
+        assert item
         props = obj.BIMStructuralProperties
         relative_matrix = props.ccs_empty.matrix_world @ obj.matrix_world.inverted()
         x_axis = relative_matrix.col[0][0:3]
         z_axis = relative_matrix.col[2][0:3]
         self.file = tool.Ifc.get()
-        ifcopenshell.api.run(
+        ifcopenshell.api.structural.edit_structural_connection_cs(
-            "structural.edit_structural_connection_cs",
             self.file,
-            structural_item=self.file.by_id(oprops.ifc_definition_id),
+            structural_item=item,
             axis=z_axis,
             ref_direction=x_axis,
         )
@@ -695,9 +700,9 @@ class AddStructuralActivity(bpy.types.Operator, tool.Ifc.Operator):
         self.props = context.scene.BIMStructuralProperties
         self.file = tool.Ifc.get()
         for obj in context.selected_objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            element = tool.Ifc.get_entity(obj)
+            if not element:
                 continue
-            element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
             applied_load_class = self.props.applicable_structural_load_types
 
             allowed_load_classes = {

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

@@ -85,14 +85,14 @@ class BIM_PT_structural_boundary_conditions(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not (tool.Ifc.get_object_by_identifier(ifc_id)):
             return False
-        if not tool.Ifc.get().by_id(props.ifc_definition_id).is_a("IfcStructuralConnection"):
+        if not tool.Ifc.get().by_id(ifc_id).is_a("IfcStructuralConnection"):
             return False
         return True
 
@@ -120,14 +120,14 @@ class BIM_PT_connected_structural_members(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not (tool.Ifc.get_object_by_identifier(ifc_id)):
             return False
-        if not tool.Ifc.get().by_id(props.ifc_definition_id).is_a("IfcStructuralConnection"):
+        if not tool.Ifc.get().by_id(ifc_id).is_a("IfcStructuralConnection"):
             return False
         return True
 
@@ -173,14 +173,14 @@ class BIM_PT_structural_member(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not tool.Ifc.get_object_by_identifier(ifc_id):
             return False
-        if not tool.Ifc.get().by_id(props.ifc_definition_id).is_a("IfcStructuralMember"):
+        if not tool.Ifc.get().by_id(ifc_id).is_a("IfcStructuralMember"):
             return False
         return True
 
@@ -216,14 +216,14 @@ class BIM_PT_structural_connection(Panel):
 
     @classmethod
     def poll(cls, context):
-        if not context.active_object:
+        if not (obj := context.active_object):
             return False
-        props = context.active_object.BIMObjectProperties
+        ifc_id = tool.Blender.get_ifc_definition_id(obj)
-        if not props.ifc_definition_id:
+        if not ifc_id:
             return False
-        if not tool.Ifc.get_object_by_identifier(props.ifc_definition_id):
+        if not tool.Ifc.get_object_by_identifier(ifc_id):
             return False
-        if not tool.Ifc.get().by_id(props.ifc_definition_id).is_a("IfcStructuralConnection"):
+        if not tool.Ifc.get().by_id(ifc_id).is_a("IfcStructuralConnection"):
             return False
         return True
 
@@ -315,7 +315,6 @@ class BIM_UL_structural_analysis_models(UIList):
             row.label(text=item.name)
 
             if context.active_object:
-                oprops = context.active_object.BIMObjectProperties
                 if item.ifc_definition_id in StructuralAnalysisModelsData.data["active_model_ids"]:
                     op = row.operator(
                         "bim.unassign_structural_analysis_model", text="", icon="KEYFRAME_HLT", emboss=False

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

@@ -187,9 +187,8 @@ class BIM_PT_ports(Panel):
             if connected_obj_name:
                 connected_obj = bpy.data.objects[connected_obj_name]
                 cols[3].operator("bim.disconnect_port", text="", icon="UNLINKED").element_id = port.id()
-                cols[4].operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = (
+                ifc_id = tool.Blender.get_ifc_definition_id(connected_obj)
-                    connected_obj.BIMObjectProperties.ifc_definition_id
+                cols[4].operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = ifc_id
-                )
                 cols[5].label(text=connected_obj_name)
             else:
                 cols[3].label(text="", icon="UNLINKED")
@@ -244,9 +243,8 @@ class BIM_PT_port(Panel):
         relating_object = bpy.data.objects[relating_object_name]
         row.label(text="Port located on:")
         row.label(text=relating_object_name)
-        row.operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = (
+        ifc_id = tool.Blender.get_ifc_definition_id(relating_object)
-            relating_object.BIMObjectProperties.ifc_definition_id
+        row.operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = ifc_id
-        )
 
         # object connected to the port
         row = layout.row(align=True)
@@ -255,9 +253,8 @@ class BIM_PT_port(Panel):
             connected_object = bpy.data.objects[connected_object_name]
             row.label(text="Port connected to:")
             row.label(text=connected_object_name)
-            row.operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = (
+            ifc_id = tool.Blender.get_ifc_definition_id(connected_object)
-                connected_object.BIMObjectProperties.ifc_definition_id
+            row.operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = ifc_id
-            )
         else:
             row.label(text="Port is not connected to any element")
 
@@ -304,9 +301,8 @@ class BIM_PT_flow_controls(Panel):
             op.flow_control = control_id
             op.flow_element = flow_element_id
             op.assign = False
-            row.operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = (
+            ifc_id = tool.Blender.get_ifc_definition_id(displayed_object)
-                displayed_object.BIMObjectProperties.ifc_definition_id
+            row.operator("bim.select_entity", text="", icon="RESTRICT_SELECT_OFF").ifc_id = ifc_id
-            )
             row.label(text=f"{displayed_object_name}")
 
         element = tool.Ifc.get_entity(context.active_object)

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

@@ -150,7 +150,8 @@ class SelectRequirement(bpy.types.Operator):
             area.spaces[0].shading.show_xray = True
             failed_ids = [e["id"] for e in failed_entities]
             for obj in context.scene.objects:
-                if obj.BIMObjectProperties.ifc_definition_id in failed_ids:
+                ifc_id = tool.Blender.get_ifc_definition_id(obj)
+                if ifc_id in failed_ids:
                     obj.color = (1, 0, 0, 1)
                 else:
                     obj.color = (1, 1, 1, 1)
@@ -175,7 +176,8 @@ class SelectFailedEntities(bpy.types.Operator):
 
         failed_ids = [e["id"] for e in failed_entities]
         for obj in context.scene.objects:
-            if obj.BIMObjectProperties.ifc_definition_id in failed_ids:
+            ifc_id = tool.Blender.get_ifc_definition_id(obj)
+            if ifc_id in failed_ids:
                 obj.select_set(True)
             else:
                 obj.select_set(False)

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

@@ -337,5 +337,5 @@ class DuplicateType(bpy.types.Operator, tool.Ifc.Operator):
         # Set duplicated type as active in current tool.
         if ifc_class in (i[0] for i in (bonsai.bim.helper.get_enum_items(props, "ifc_class", context) or ()) if i):
             props.ifc_class = new.is_a()
-            props.relating_type_id = str(new_obj.BIMObjectProperties.ifc_definition_id)
+            props.relating_type_id = str(tool.Blender.get_ifc_definition_id(new_obj))
         return {"FINISHED"}

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

@@ -46,7 +46,9 @@ class BIM_PT_type(Panel):
         if not TypeData.is_loaded:
             TypeData.load()
 
-        oprops = context.active_object.BIMObjectProperties
+        obj = context.active_object
+        assert obj
+        oprops = tool.Blender.get_object_bim_props(obj)
 
         if TypeData.data["is_product"]:
             self.draw_product_ui(context)
@@ -54,21 +56,19 @@ class BIM_PT_type(Panel):
             self.draw_type_ui(context)
 
     def draw_type_ui(self, context):
-        props = context.active_object.BIMTypeProperties
+        oprops = tool.Blender.get_object_bim_props(context.active_object)
-        oprops = context.active_object.BIMObjectProperties
         row = self.layout.row(align=True)
         row.label(text=f"{TypeData.data['total_instances']} Typed Objects")
         select_type_objects_row = row.row(align=True)
         select_type_objects_row.operator("bim.select_type_objects", icon="RESTRICT_SELECT_OFF", text="")
         select_type_objects_row.enabled = int(TypeData.data["total_instances"]) > 0
         op = row.operator("bim.duplicate_type", icon="DUPLICATE", text="")
-        op.element = context.active_object.BIMObjectProperties.ifc_definition_id
+        op.element = oprops.ifc_definition_id
         row.operator("bim.auto_rename_occurrences", icon="ITALIC", text="")
 
     def draw_product_ui(self, context):
         layout = self.layout
         props = context.active_object.BIMTypeProperties
-        oprops = context.active_object.BIMObjectProperties
 
         if props.is_editing_type:
             row = layout.row(align=True)

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

@@ -215,8 +215,8 @@ class AddFilling(bpy.types.Operator, tool.Ifc.Operator):
         if opening is None:
             return {"FINISHED"}
         self.file = tool.Ifc.get()
-        element_id = obj.BIMObjectProperties.ifc_definition_id
+        element_id = tool.Blender.get_object_bim_props(obj).ifc_definition_id
-        opening_id = opening.BIMObjectProperties.ifc_definition_id
+        opening_id = tool.Blender.get_object_bim_props(opening).ifc_definition_id
         if not element_id or not opening_id or element_id == opening_id:
             return {"FINISHED"}
         ifcopenshell.api.run(

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

@@ -52,8 +52,6 @@ class BIM_PT_voids(Panel):
         if not VoidsData.is_loaded:
             VoidsData.load()
 
-        props = context.active_object.BIMObjectProperties
-
         if len(context.selected_objects) >= 2:
             row = self.layout.row(align=True)
             op = row.operator("bim.add_opening", icon="ADD", text="Add Opening")

src/bonsai/bonsai/bim/operator.py

@@ -857,7 +857,9 @@ class FetchObjectPassport(bpy.types.Operator):
 
     def execute(self, context):
         # TODO: this is dead code, awaiting reimplementation. See #1222.
-        for reference in context.active_object.BIMObjectProperties.document_references:
+        obj = context.active_object
+        props = tool.Blender.get_object_bim_props(obj)
+        for reference in props.document_references:
             bim_props = tool.Blender.get_bim_props()
             reference = bim_props.document_references[reference.name]
             if reference.location[-6:] == ".blend":

src/bonsai/bonsai/tool/blender.py

@@ -41,7 +41,7 @@ from typing import Any, Optional, Union, Literal, Iterable, Callable, TypeVar, G
 from typing_extensions import assert_never
 
 if TYPE_CHECKING:
-    from bonsai.bim.prop import BIMProperties
+    from bonsai.bim.prop import BIMProperties, BIMObjectProperties
 
 
 VIEWPORT_ATTRIBUTES = [
@@ -192,7 +192,8 @@ class Blender(bonsai.core.tool.Blender):
         if context is None:
             context = bpy.context
         if obj_type == "Object":
-            return bpy.data.objects.get(obj).BIMObjectProperties.ifc_definition_id
+            props = tool.Blender.get_object_bim_props(bpy.data.objects[obj])
+            return props.ifc_definition_id
         elif obj_type == "Material":
             props = tool.Material.get_material_props()
             return props.materials[props.active_material_index].ifc_definition_id
@@ -221,7 +222,8 @@ class Blender(bonsai.core.tool.Blender):
 
     @classmethod
     def is_ifc_object(cls, obj: bpy.types.Object) -> bool:
-        return bool(obj.BIMObjectProperties.ifc_definition_id)
+        props = tool.Blender.get_object_bim_props(obj)
+        return bool(props.ifc_definition_id)
 
     @classmethod
     def is_ifc_class_active(cls, ifc_class: str) -> bool:
@@ -880,7 +882,7 @@ class Blender(bonsai.core.tool.Blender):
     @classmethod
     def get_layer_collection(cls, collection: bpy.types.Collection) -> Union[bpy.types.LayerCollection, None]:
         project = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-        project_collection = project.BIMObjectProperties.collection
+        project_collection = tool.Blender.get_object_bim_props(project).collection
         for layer_collection in bpy.context.view_layer.layer_collection.children:
             if layer_collection.collection == project_collection:
                 for layer_collection2 in layer_collection.children:
@@ -1019,23 +1021,28 @@ class Blender(bonsai.core.tool.Blender):
 
         @classmethod
         def is_editing_railing_path(cls, obj: bpy.types.Object):
-            return obj.BIMRailingProperties.is_editing_path
+            props = tool.Model.get_railing_props(obj)
+            return props.is_editing_path
 
         @classmethod
         def is_editing_roof_path(cls, obj: bpy.types.Object) -> bool:
-            return obj.BIMRoofProperties.is_editing_path
+            props = tool.Model.get_roof_props(obj)
+            return props.is_editing_path
 
         @classmethod
         def is_editing_railing_parameters(cls, obj: bpy.types.Object) -> bool:
-            return obj.BIMRailingProperties.is_editing
+            props = tool.Model.get_railing_props(obj)
+            return props.is_editing
 
         @classmethod
         def is_editing_roof_parameters(cls, obj: bpy.types.Object) -> bool:
-            return obj.BIMRoofProperties.is_editing
+            props = tool.Model.get_roof_props(obj)
+            return props.is_editing
 
         @classmethod
         def is_editing_window_parameters(cls, obj: bpy.types.Object) -> bool:
-            return obj.BIMWindowProperties.is_editing
+            props = tool.Model.get_window_props(obj)
+            return props.is_editing
 
         @classmethod
         def is_editing_door_parameters(cls, obj: bpy.types.Object) -> bool:
@@ -1044,7 +1051,8 @@ class Blender(bonsai.core.tool.Blender):
 
         @classmethod
         def is_editing_stair_parameters(cls, obj: bpy.types.Object) -> bool:
-            return obj.BIMStairProperties.is_editing
+            props = tool.Model.get_stair_props(obj)
+            return props.is_editing
 
         @classmethod
         def is_modifier_with_non_editable_path(cls, element: entity_instance) -> bool:
@@ -1545,3 +1553,11 @@ class Blender(bonsai.core.tool.Blender):
         if scene is None:
             scene = bpy.context.scene
         return scene.BIMProperties
+
+    @classmethod
+    def get_object_bim_props(cls, obj: bpy.types.Object) -> BIMObjectProperties:
+        return obj.BIMObjectProperties
+
+    @classmethod
+    def get_ifc_definition_id(cls, obj: bpy.types.Object) -> int:
+        return tool.Blender.get_object_bim_props(obj).ifc_definition_id

src/bonsai/bonsai/tool/cad.py

@@ -28,7 +28,7 @@
 #  - An arc is reconstructed from 3 points instead of a full circle
 #  - You can now derive the center from an arc without generating geometry
 
-
+from __future__ import annotations
 import sys
 import bpy
 import math
@@ -36,12 +36,20 @@ import bmesh
 import mathutils.geometry
 from mathutils import Vector, Matrix, geometry
 import itertools
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from bonsai.bim.module.cad.prop import BIMCadProperties
 
 
 VTX_PRECISION = 1.0e-5
 
 
 class Cad:
+    @classmethod
+    def get_cad_props(cls) -> BIMCadProperties:
+        return bpy.context.scene.BIMCadProperties
+
     @classmethod
     def is_point_on_edge(cls, p, edge):
         """

src/bonsai/bonsai/tool/collector.py

@@ -29,7 +29,7 @@ class Collector(bonsai.core.tool.Collector):
         """Links an object to an appropriate Blender collection."""
         if should_clean_users_collection:
             for users_collection in obj.users_collection:
-                if obj.BIMObjectProperties.collection == users_collection:
+                if tool.Blender.get_object_bim_props(obj).collection == users_collection:
                     continue
                 # Users are free to use extra collections for their own
                 # purposes except for the reserved keyword "Ifc" and
@@ -87,7 +87,7 @@ class Collector(bonsai.core.tool.Collector):
             if collection := cls._create_own_collection(obj):
                 cls.link_collection_object_safe(collection, obj)
                 project_obj = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-                cls.link_collection_child_safe(project_obj.BIMObjectProperties.collection, collection)
+                cls.link_collection_child_safe(tool.Blender.get_object_bim_props(project_obj).collection, collection)
         elif (
             tool.Ifc.get_schema() != "IFC2X3"
             and element.is_a("IfcSpatialElement")
@@ -98,21 +98,21 @@ class Collector(bonsai.core.tool.Collector):
             if collection := cls._create_own_collection(obj):
                 cls.link_collection_object_safe(collection, obj)
                 project_obj = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-                cls.link_collection_child_safe(project_obj.BIMObjectProperties.collection, collection)
+                cls.link_collection_child_safe(tool.Blender.get_object_bim_props(project_obj).collection, collection)
         elif element.is_a("IfcAnnotation") and element.ObjectType == "DRAWING":
             if collection := cls._create_own_collection(obj):
                 cls.link_collection_object_safe(collection, obj)
                 project_obj = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-                cls.link_collection_child_safe(project_obj.BIMObjectProperties.collection, collection)
+                cls.link_collection_child_safe(tool.Blender.get_object_bim_props(project_obj).collection, collection)
         elif element.is_a("IfcAnnotation") and (drawing_obj := cls.get_annotation_drawing_obj(element)):
-            cls.link_collection_object_safe(drawing_obj.BIMObjectProperties.collection, obj)
+            cls.link_collection_object_safe(tool.Blender.get_object_bim_props(drawing_obj).collection, obj)
         elif container := ifcopenshell.util.element.get_container(element):
             while container.is_a("IfcSpace"):
                 container = ifcopenshell.util.element.get_aggregate(container)
             container_obj = tool.Ifc.get_object(container)
-            if not (collection := container_obj.BIMObjectProperties.collection):
+            if not (collection := tool.Blender.get_object_bim_props(container_obj).collection):
                 cls.assign(container_obj)
-                collection = container_obj.BIMObjectProperties.collection
+                collection = tool.Blender.get_object_bim_props(container_obj).collection
             cls.link_collection_object_safe(collection, obj)
         else:
             collection = cls._create_project_child_collection("Unsorted")
@@ -128,7 +128,7 @@ class Collector(bonsai.core.tool.Collector):
             return collection
         collection = bpy.data.collections.new(name)
         project_obj = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-        project_obj.BIMObjectProperties.collection.children.link(collection)
+        tool.Blender.get_object_bim_props(project_obj).collection.children.link(collection)
         if layer_collection := tool.Blender.get_layer_collection(collection):
             cls.set_layer_collection_visibility(layer_collection)
         return collection
@@ -136,11 +136,12 @@ class Collector(bonsai.core.tool.Collector):
     @classmethod
     def _create_own_collection(cls, obj: bpy.types.Object) -> bpy.types.Collection:
         """get or create own collection for the element"""
-        if obj.BIMObjectProperties.collection:
+        props = tool.Blender.get_object_bim_props(obj)
-            obj.BIMObjectProperties.collection.name = obj.name
+        if props.collection:
+            props.collection.name = obj.name
             return
         collection = bpy.data.collections.new(obj.name)
-        obj.BIMObjectProperties.collection = collection
+        props.collection = collection
         collection.BIMCollectionProperties.obj = obj
         return collection
 
@@ -184,7 +185,8 @@ class Collector(bonsai.core.tool.Collector):
     @classmethod
     def reset_default_visibility(cls) -> None:
         project = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-        project_collection = project.BIMObjectProperties.collection
+        assert project
+        project_collection = tool.Blender.get_object_bim_props(project).collection
         for layer_collection in bpy.context.view_layer.layer_collection.children:
             if layer_collection.collection == project_collection:
                 for layer_collection2 in layer_collection.children:

src/bonsai/bonsai/tool/covering.py

@@ -16,17 +16,26 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import annotations
 import bpy
 import ifcopenshell
 import ifcopenshell.util.element
 import bonsai.core.tool
 import bonsai.tool as tool
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from bonsai.bim.module.covering.prop import BIMCoveringProperties
 
 
 class Covering(bonsai.core.tool.Covering):
+    @classmethod
+    def get_covering_props(cls) -> BIMCoveringProperties:
+        return bpy.context.scene.BIMCoveringProperties
+
     @classmethod
     def get_z_from_ceiling_height(cls) -> float:
-        props = bpy.context.scene.BIMCoveringProperties
+        props = cls.get_covering_props()
         return props.ceiling_height
 
     #    def toggle_spaces_visibility_wired_and_textured(cls, spaces):

src/bonsai/bonsai/tool/drawing.py

@@ -524,7 +524,7 @@ class Drawing(bonsai.core.tool.Drawing):
     def get_drawing_collection(cls, drawing: ifcopenshell.entity_instance) -> Union[bpy.types.Collection, None]:
         obj = tool.Ifc.get_object(drawing)
         if obj:
-            return obj.BIMObjectProperties.collection
+            return tool.Blender.get_object_bim_props(obj).collection
 
     @classmethod
     def get_drawing_group(cls, drawing: ifcopenshell.entity_instance) -> ifcopenshell.entity_instance:
@@ -1516,8 +1516,8 @@ class Drawing(bonsai.core.tool.Drawing):
             dst = src.copy()
             dst.data = dst.data.copy()
             dst.name = dst.name.replace("IfcGridAxis/", "")
-            dst.BIMObjectProperties.ifc_definition_id = 0
+            tool.Blender.get_object_bim_props(dst).ifc_definition_id = 0
-            tool.Geometry.get_geometry_props(dst).ifc_definition_id = 0
+            tool.Geometry.get_geometry_props(dst.data).ifc_definition_id = 0
             return dst
 
         def disassemble(obj: bpy.types.Object) -> tuple[bpy.types.Object, bmesh.types.BMesh]:
@@ -1888,7 +1888,7 @@ class Drawing(bonsai.core.tool.Drawing):
         return bool(
             camera is not None
             and camera.type == "CAMERA"
-            and camera.BIMObjectProperties.ifc_definition_id
+            and tool.Blender.get_ifc_definition_id(camera)
             and area is not None
         )
 
@@ -1910,11 +1910,12 @@ class Drawing(bonsai.core.tool.Drawing):
     def isolate_camera_collection(cls, camera: bpy.types.Object) -> None:
         drawings = [e for e in tool.Ifc.get().by_type("IfcAnnotation") if e.ObjectType == "DRAWING"]
         drawing_collections = []
-        camera_collection = camera.BIMObjectProperties.collection
+        camera_collection = tool.Blender.get_object_bim_props(camera).collection
         for drawing in drawings:
             if not (drawing_obj := tool.Ifc.get_object(drawing)):
                 continue
-            if not (drawing_collection := drawing_obj.BIMObjectProperties.collection):
+            oprops = tool.Blender.get_object_bim_props(drawing_obj)
+            if not (drawing_collection := oprops.collection):
                 continue
             if drawing_obj == camera:
                 drawing_collection.hide_render = False
@@ -1922,7 +1923,7 @@ class Drawing(bonsai.core.tool.Drawing):
                 drawing_collection.hide_render = True
 
         project = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-        project_collection = project.BIMObjectProperties.collection
+        project_collection = tool.Blender.get_object_bim_props(project).collection
         for layer_collection in bpy.context.view_layer.layer_collection.children:
             if layer_collection.collection == project_collection:
                 for layer_collection2 in layer_collection.children:

src/bonsai/bonsai/tool/geometry.py

@@ -235,7 +235,7 @@ class Geometry(bonsai.core.tool.Geometry):
                     bpy.data.objects.remove(axis_obj)
                 ifcopenshell.api.grid.remove_grid_axis(tool.Ifc.get(), axis=axis)
 
-        collection = obj.BIMObjectProperties.collection
+        collection = tool.Blender.get_object_bim_props(obj).collection
         if collection:
             parent = ifcopenshell.util.element.get_aggregate(element)
             if not parent:
@@ -243,7 +243,7 @@ class Geometry(bonsai.core.tool.Geometry):
             if parent:
                 parent_obj = tool.Ifc.get_object(parent)
                 if parent_obj:
-                    parent_collection = parent_obj.BIMObjectProperties.collection
+                    parent_collection = tool.Blender.get_object_bim_props(parent_obj).collection
                     for child in collection.children:
                         parent_collection.children.link(child)
                     for child_object in collection.objects:
@@ -557,11 +557,9 @@ class Geometry(bonsai.core.tool.Geometry):
 
     @classmethod
     def get_cartesian_point_offset(cls, obj: bpy.types.Object) -> npt.NDArray[np.float64] | None:
-        if (
+        props = tool.Blender.get_object_bim_props(obj)
-            obj.BIMObjectProperties.blender_offset_type == "CARTESIAN_POINT"
+        if props.blender_offset_type == "CARTESIAN_POINT" and props.cartesian_point_offset:
-            and obj.BIMObjectProperties.cartesian_point_offset
+            return np.array(tuple(map(float, props.cartesian_point_offset.split(","))))
-        ):
-            return np.array(tuple(map(float, obj.BIMObjectProperties.cartesian_point_offset.split(","))))
 
     @classmethod
     def get_element_type(cls, element: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
@@ -1084,8 +1082,9 @@ class Geometry(bonsai.core.tool.Geometry):
     @classmethod
     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())
+        props = tool.Blender.get_object_bim_props(obj)
-        obj.BIMObjectProperties.rotation_checksum = repr(np.array(obj.matrix_world.to_3x3()).tobytes())
+        props.location_checksum = repr(np.array(obj.matrix_world.translation).tobytes())
+        props.rotation_checksum = repr(np.array(obj.matrix_world.to_3x3()).tobytes())
 
     @classmethod
     def remove_connection(cls, connection: ifcopenshell.entity_instance) -> None:
@@ -1570,8 +1569,9 @@ class Geometry(bonsai.core.tool.Geometry):
     def get_blender_offset_type(cls, obj: bpy.types.Object) -> Optional[str]:
         props = tool.Georeference.get_georeference_props()
         if props.has_blender_offset:
-            if (result := obj.BIMObjectProperties.blender_offset_type) == "NONE":
+            props = tool.Blender.get_object_bim_props(obj)
-                result = obj.BIMObjectProperties.blender_offset_type = "OBJECT_PLACEMENT"
+            if (result := props.blender_offset_type) == "NONE":
+                result = props.blender_offset_type = "OBJECT_PLACEMENT"
             return result
 
     @classmethod

src/bonsai/bonsai/tool/ifc.py

@@ -77,13 +77,14 @@ class Ifc(bonsai.core.tool.Ifc):
             return False
         if element and (element.is_a("IfcTypeProduct") or element.is_a("IfcProject")):
             return False
-        if not obj.BIMObjectProperties.location_checksum:
+        oprops = tool.Blender.get_object_bim_props(obj)
+        if not oprops.location_checksum:
             return True  # Let's be conservative
-        loc_check = np.frombuffer(eval(obj.BIMObjectProperties.location_checksum))
+        loc_check = np.frombuffer(eval(oprops.location_checksum))
         loc_real = np.array(obj.matrix_world.translation).flatten()
         if not np.allclose(loc_check, loc_real, atol=1e-4):  # 0.1 mm
             return True
-        rot_check = np.frombuffer(eval(obj.BIMObjectProperties.rotation_checksum)).reshape(3, 3)
+        rot_check = np.frombuffer(eval(oprops.rotation_checksum)).reshape(3, 3)
         rot_real = np.array(obj.matrix_world.to_3x3())
         rot_dot = np.dot(rot_check, rot_real.T)
         angle_rad = np.arccos(np.clip((np.trace(rot_dot) - 1) / 2, -1, 1))
@@ -107,7 +108,7 @@ class Ifc(bonsai.core.tool.Ifc):
 
         props = None
         if isinstance(obj, bpy.types.Object):
-            props = obj.BIMObjectProperties
+            props = tool.Blender.get_object_bim_props(obj)
         elif isinstance(obj, bpy.types.Material):
             props = obj.BIMStyleProperties
         else:

src/bonsai/bonsai/tool/ifcgit.py

@@ -397,9 +397,9 @@ class IfcGit:
         bpy.ops.object.select_all(action="DESELECT")
 
         for obj in bpy.context.visible_objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            props = tool.Blender.get_object_bim_props(obj)
+            if not (step_id := props.ifc_definition_id):
                 continue
-            step_id = obj.BIMObjectProperties.ifc_definition_id
             if step_id in step_ids["modified"]:
                 obj.color = (0.3, 0.3, 1.0, 1)
                 obj.select_set(True)

src/bonsai/bonsai/tool/loader.py

@@ -929,6 +929,7 @@ class Loader(bonsai.core.tool.Loader):
 
     @classmethod
     def apply_blender_offset_to_matrix_world(cls, obj: bpy.types.Object, matrix: np.ndarray) -> Matrix:
+        oprops = tool.Blender.get_object_bim_props(obj)
         if (
             not obj.data
             and tool.Cad.is_x(matrix[0][3], 0)
@@ -939,13 +940,13 @@ class Loader(bonsai.core.tool.Loader):
             # positionally significant and is left alone. This handles
             # scenarios where often spatial elements are left at 0,0,0 and
             # everything else is at map coordinates.
-            obj.BIMObjectProperties.blender_offset_type = "NOT_APPLICABLE"
+            oprops.blender_offset_type = "NOT_APPLICABLE"
             return Matrix(matrix.tolist())
 
         if obj.data and obj.data.get("has_cartesian_point_offset", None):
-            obj.BIMObjectProperties.blender_offset_type = "CARTESIAN_POINT"
+            oprops.blender_offset_type = "CARTESIAN_POINT"
             if cartesian_point_offset := obj.data.get("cartesian_point_offset", None):
-                obj.BIMObjectProperties.cartesian_point_offset = cartesian_point_offset
+                oprops.cartesian_point_offset = cartesian_point_offset
                 offset_xyz = list(map(float, cartesian_point_offset.split(","))) + [1.0]
                 offset_xyz = matrix @ offset_xyz
                 matrix[0][3] = offset_xyz[0]
@@ -954,8 +955,8 @@ class Loader(bonsai.core.tool.Loader):
 
         props = tool.Georeference.get_georeference_props()
         if props.has_blender_offset:
-            if obj.BIMObjectProperties.blender_offset_type == "NONE":
+            if oprops.blender_offset_type == "NONE":
-                obj.BIMObjectProperties.blender_offset_type = "OBJECT_PLACEMENT"
+                oprops.blender_offset_type = "OBJECT_PLACEMENT"
             matrix = ifcopenshell.util.geolocation.global2local(
                 matrix,
                 float(props.blender_offset_x) * cls.unit_scale,

src/bonsai/bonsai/tool/model.py

@@ -55,7 +55,15 @@ T = TypeVar("T")
 V_ = tool.Blender.V_
 
 if TYPE_CHECKING:
-    from bonsai.bim.module.model.prop import BIMModelProperties, BIMDoorProperties
+    from bonsai.bim.module.model.prop import (
+        BIMModelProperties,
+        BIMDoorProperties,
+        BIMArrayProperties,
+        BIMRoofProperties,
+        BIMWindowProperties,
+        BIMStairProperties,
+        BIMRailingProperties,
+    )
 
 
 class Model(bonsai.core.tool.Model):
@@ -67,6 +75,26 @@ class Model(bonsai.core.tool.Model):
     def get_door_props(cls, obj: bpy.types.Object) -> BIMDoorProperties:
         return obj.BIMDoorProperties
 
+    @classmethod
+    def get_window_props(cls, obj: bpy.types.Object) -> BIMWindowProperties:
+        return obj.BIMWindowProperties
+
+    @classmethod
+    def get_stair_props(cls, obj: bpy.types.Object) -> BIMStairProperties:
+        return obj.BIMStairProperties
+
+    @classmethod
+    def get_roof_props(cls, obj: bpy.types.Object) -> BIMRoofProperties:
+        return obj.BIMRoofProperties
+
+    @classmethod
+    def get_railing_props(cls, obj: bpy.types.Object) -> BIMRailingProperties:
+        return obj.BIMRailingProperties
+
+    @classmethod
+    def get_array_props(cls, obj: bpy.types.Object) -> BIMArrayProperties:
+        return obj.BIMArrayProperties
+
     @classmethod
     def convert_si_to_unit(cls, value: T) -> T:
         if isinstance(value, (tuple, list)):
@@ -1989,9 +2017,9 @@ class Model(bonsai.core.tool.Model):
         if z < 0 and y < 0:
             y = abs(y)
             z = abs(z)
-        if z < 0 and y >=0:
+        if z < 0 and y >= 0:
             vector = Vector((0, -1))
-            
+
         x_angle = vector.angle_signed(Vector((y, z)))
 
         return x_angle

src/bonsai/bonsai/tool/root.py

@@ -409,7 +409,8 @@ class Root(bonsai.core.tool.Root):
     def set_object_name(cls, obj: bpy.types.Object, element: ifcopenshell.entity_instance) -> None:
         name = tool.Loader.get_name(element)
         if obj.name != name:
-            obj.BIMObjectProperties.is_renaming = True
+            props = tool.Blender.get_object_bim_props(obj)
+            props.is_renaming = True
             obj.name = name  # The handler will trigger, and reset is_renaming to False
 
     @classmethod

src/bonsai/bonsai/tool/sequence.py

@@ -1158,7 +1158,7 @@ class Sequence(bonsai.core.tool.Sequence):
         bpy.context.scene.frame_start = 1
         bpy.context.scene.frame_end = 2
         for obj in bpy.data.objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            if not (ifc_id := tool.Blender.get_ifc_definition_id(obj)):
                 continue
             obj.color = (1.0, 1.0, 1.0, 1)
             obj.hide_viewport = False
@@ -1317,7 +1317,7 @@ class Sequence(bonsai.core.tool.Sequence):
     @classmethod
     def clear_objects_animation(cls, include_blender_objects=True):
         for obj in bpy.data.objects:
-            if not include_blender_objects and not obj.BIMObjectProperties.ifc_definition_id:
+            if not include_blender_objects and not (ifc_id := tool.Blender.get_ifc_definition_id(obj)):
                 continue
             cls.clear_object_animation(obj)
             cls.clear_object_color(obj)
@@ -1326,13 +1326,14 @@ class Sequence(bonsai.core.tool.Sequence):
     @classmethod
     def animate_objects(cls, settings, frames, animation_type=""):
         for obj in bpy.data.objects:
-            if not obj.BIMObjectProperties.ifc_definition_id:
+            element = tool.Ifc.get_entity(obj)
+            if not element:
                 continue
-            if tool.Ifc.get().by_id(obj.BIMObjectProperties.ifc_definition_id).is_a("IfcSpace"):
+            if element.is_a("IfcSpace"):
                 cls.hide_object(obj)
                 continue
             cls.earliest_frame = None
-            product_frames = frames.get(obj.BIMObjectProperties.ifc_definition_id, [])
+            product_frames = frames.get(element.id(), [])
             for product_frame in product_frames:
                 if product_frame["relationship"] == "input":
                     cls.animate_input(obj, settings["start_frame"], product_frame, animation_type)

src/bonsai/bonsai/tool/spatial.py

@@ -1180,9 +1180,9 @@ class Spatial(bonsai.core.tool.Spatial):
         SpatialDecompositionData.data["default_container"] = SpatialDecompositionData.default_container()
 
         project = tool.Ifc.get_object(tool.Ifc.get().by_type("IfcProject")[0])
-        project_collection = project.BIMObjectProperties.collection
+        project_collection = tool.Blender.get_object_bim_props(project).collection
         obj = tool.Ifc.get_object(container)
-        if obj and (collection := obj.BIMObjectProperties.collection):
+        if obj and (collection := tool.Blender.get_object_bim_props(obj).collection):
             for layer_collection in bpy.context.view_layer.layer_collection.children:
                 if layer_collection.collection == project_collection:
                     for layer_collection2 in layer_collection.children:

src/bonsai/bonsai/tool/structural.py

@@ -110,7 +110,8 @@ class Structural(bonsai.core.tool.Structural):
     def get_product_or_active_object(cls, product: str) -> Union[bpy.types.Object, None]:
         product = bpy.data.objects.get(product) if product else bpy.context.active_object
         try:
-            if product.BIMObjectProperties.ifc_definition_id:
+            props = tool.Blender.get_object_bim_props(product)
+            if props.ifc_definition_id:
                 return product
             else:
                 return None

src/bonsai/bonsai/tool/surveyor.py

@@ -33,7 +33,7 @@ class Surveyor(bonsai.core.tool.Surveyor):
         M_TRANSLATION = (slice(0, 3), 3)
         matrix = np.array(obj.matrix_world)
         props = tool.Georeference.get_georeference_props()
-        if props.has_blender_offset and obj.BIMObjectProperties.blender_offset_type != "NOT_APPLICABLE":
+        if props.has_blender_offset and tool.Blender.get_object_bim_props(obj).blender_offset_type != "NOT_APPLICABLE":
             unit_scale = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
             coordinate_offset = tool.Geometry.get_cartesian_point_offset(obj)
             if coordinate_offset is not None:

src/bonsai/bonsai/tool/system.py

@@ -189,7 +189,7 @@ class System(bonsai.core.tool.System):
 
         container = ifcopenshell.util.element.get_container(element)
         if container:
-            collection = tool.Ifc.get_object(container).BIMObjectProperties.collection
+            collection = tool.Blender.get_object_bim_props(tool.Ifc.get_object(container)).collection
             ifc_importer.collections[container.GlobalId] = collection
         ifc_importer.place_objects_in_collections()
 

src/bonsai/test/bim/bootstrap.py

@@ -192,12 +192,12 @@ def the_object_name_does_not_exist(name):
 
 def the_object_name_is_an_ifc_class(name, ifc_class):
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     assert element.is_a(ifc_class), f'Object "{name}" is an {element.is_a()}'
 
 
 def the_object_name_is_not_an_ifc_element(name):
-    id = the_object_name_exists(name).BIMObjectProperties.ifc_definition_id
+    id = tool.Blender.get_ifc_definition_id(the_object_name_exists(name))
     assert id == 0, f"The ID is {id}"
 
 
@@ -229,7 +229,7 @@ def the_object_name_is_placed_in_the_collection_collection(name, collection):
 
 def the_object_name_has_a_type_representation_of_context(name, type, context):
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     context, subcontext, target_view = context.split("/")
     assert ifcopenshell.util.representation.get_representation(
         element, context, subcontext or None, target_view or None
@@ -238,7 +238,7 @@ def the_object_name_has_a_type_representation_of_context(name, type, context):
 
 def the_object_name_is_contained_in_container_name(name, container_name):
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     container = ifcopenshell.util.element.get_container(element)
     if not container:
         assert False, f'Object "{name}" is not in any container'
@@ -257,8 +257,8 @@ def i_delete_the_selected_objects():
 
 def the_object_name1_and_name2_are_different_elements(name1, name2):
     ifc = an_ifc_file_exists()
-    element1 = ifc.by_id(the_object_name_exists(name1).BIMObjectProperties.ifc_definition_id)
+    element1 = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name1)))
-    element2 = ifc.by_id(the_object_name_exists(name2).BIMObjectProperties.ifc_definition_id)
+    element2 = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name2)))
     assert element1 != element2, f"Objects {name1} and {name2} have same elements {element1} and {element2}"
 
 
@@ -284,7 +284,7 @@ def the_object_name1_has_no_boolean_difference_by_name2(name1, name2):
 
 def the_object_name_is_voided_by_void(name, void):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     for rel in element.HasOpenings:
         if rel.RelatedOpeningElement.Name == void:
             return True
@@ -293,7 +293,7 @@ def the_object_name_is_voided_by_void(name, void):
 
 def the_object_name_is_not_voided_by_void(name, void):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     for rel in element.HasOpenings:
         if rel.RelatedOpeningElement.Name == void:
             assert False, "A void was found"
@@ -301,21 +301,21 @@ def the_object_name_is_not_voided_by_void(name, void):
 
 def the_object_name_is_not_voided(name):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     if any(element.HasOpenings):
         assert False, "An opening was found"
 
 
 def the_object_name_is_not_a_void(name):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     if any(element.VoidsElements):
         assert False, "A void was found"
 
 
 def the_void_name_is_filled_by_filling(name, filling):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     if any(rel.RelatedBuildingElement.Name == filling for rel in element.HasFillings):
         return True
     assert False, "No filling found"
@@ -323,14 +323,14 @@ def the_void_name_is_filled_by_filling(name, filling):
 
 def the_void_name_is_not_filled_by_filling(name, filling):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     if any(rel.RelatedBuildingElement.Name == filling for rel in element.HasFillings):
         assert False, "A filling was found"
 
 
 def the_object_name_is_not_a_filling(name):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     if any(element.FillsVoids):
         assert False, "A filling was found"
 

src/bonsai/test/bim/test_feature.py

@@ -718,8 +718,8 @@ def the_collection_exclude_status_is(name: str, exclude: str) -> None:
 @then(parsers.parse('the object "{name1}" and "{name2}" are different elements'))
 def the_object_name1_and_name2_are_different_elements(name1, name2):
     ifc = an_ifc_file_exists()
-    element1 = ifc.by_id(the_object_name_exists(name1).BIMObjectProperties.ifc_definition_id)
+    element1 = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name1)))
-    element2 = ifc.by_id(the_object_name_exists(name2).BIMObjectProperties.ifc_definition_id)
+    element2 = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name2)))
     assert element1 != element2, f"Objects {name1} and {name2} have same elements {element1} and {element2}"
 
 
@@ -732,7 +732,7 @@ def the_object_name_has_a_body_of_value(name, value):
 @then(parsers.parse('the object "{name}" has a "{type}" representation of "{context}"'))
 def the_object_name_has_a_representation_type_of_context(name, type, context):
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     context, subcontext, target_view = context.split("/")
     rep = ifcopenshell.util.representation.get_representation(element, context, subcontext or None, target_view or None)
     assert rep
@@ -808,7 +808,7 @@ def the_object_name_should_display_as_mode(name, mode):
 @then(parsers.parse('the object "{name}" is voided by "{void}"'))
 def the_object_name_is_voided_by_void(name, void):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     assert any((rel for rel in element.HasOpenings if rel.RelatedOpeningElement.Name == void)), "No void found"
 
 
@@ -824,7 +824,7 @@ def the_object_name_is_not_voided_by_void(name, void):
 @then(parsers.parse('the object "{name}" is not voided'))
 def the_object_name_is_not_voided(name):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     assert not element.HasOpenings, "A void was found"
 
 
@@ -832,7 +832,7 @@ def the_object_name_is_not_voided(name):
 def the_object_name_is_a_void(name):
     ifc = tool.Ifc.get()
     obj = the_object_name_exists(name)
-    element = ifc.by_id(obj.BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(obj))
     assert any((element.VoidsElements)), "No void was found"
 
 
@@ -872,14 +872,14 @@ def the_object_name_is_not_visible(name):
 @then(parsers.parse('the object "{name}" is an "{ifc_class}"'))
 def the_object_name_is_an_ifc_class(name, ifc_class):
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     assert element.is_a(ifc_class), f'Object "{name}" is an {element.is_a()}'
 
 
 @then(parsers.parse('the object "{name}" is not an IFC element'))
 def the_object_name_is_not_an_ifc_element(name):
     obj = the_object_name_exists(name)
-    ifc_definition_id = obj.BIMObjectProperties.ifc_definition_id
+    ifc_definition_id = tool.Blender.get_ifc_definition_id(obj)
     assert ifc_definition_id == 0, f"The object {obj} has an ID of {ifc_definition_id}"
 
 
@@ -897,14 +897,14 @@ def the_object_name_has_ifc_representation_data(name):
 @then(parsers.parse('the material "{name}" is an IFC material'))
 def the_material_name_is_an_ifc_material(name):
     obj = the_material_name_exists(name)
-    ifc_definition_id = obj.BIMObjectProperties.ifc_definition_id
+    ifc_definition_id = tool.Blender.get_ifc_definition_id(obj)
     assert ifc_definition_id != 0, f"The material {obj} has no ID: {ifc_definition_id}"
 
 
 @then(parsers.parse('the material "{name}" is not an IFC material'))
 def the_material_name_is_not_an_ifc_material(name):
     obj = the_material_name_exists(name)
-    ifc_definition_id = obj.BIMObjectProperties.ifc_definition_id
+    ifc_definition_id = tool.Blender.get_ifc_definition_id(obj)
     assert ifc_definition_id == 0, f"The material {obj} has an ID of {ifc_definition_id}"
 
 
@@ -937,7 +937,7 @@ def the_object_name_has_number_vertices(name, number):
 @then(parsers.parse('the void "{name}" is filled by "{filling}"'))
 def the_void_name_is_filled_by_filling(name, filling):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     assert any((rel.RelatedBuildingElement.Name == filling for rel in element.HasFillings)), "No filling found"
 
 
@@ -954,7 +954,7 @@ def the_void_name_is_not_filled_by_filling(name, filling):
 @then(parsers.parse('the object "{name}" is not a filling'))
 def the_object_name_is_not_a_filling(name):
     ifc = tool.Ifc.get()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     assert not any(element.FillsVoids), "A filling was found"
 
 
@@ -1010,8 +1010,9 @@ def prop_is_roughly_value(prop, value):
 def the_object_name_has_a_cartesian_point_offset_of_offset(name: str, offset: str) -> None:
     offset = replace_variables(offset)
     obj = the_object_name_exists(name)
-    assert obj.BIMObjectProperties.blender_offset_type == "CARTESIAN_POINT"
+    props = tool.Blender.get_object_props(obj)
-    obj_offset = np.array(tuple(map(float, obj.BIMObjectProperties.cartesian_point_offset.split(","))))
+    assert props.blender_offset_type == "CARTESIAN_POINT"
+    obj_offset = np.array(tuple(map(float, props.cartesian_point_offset.split(","))))
     offset = np.array(tuple(map(float, offset.split(","))))
     assert np.allclose(obj_offset, offset)
 
@@ -1169,7 +1170,7 @@ def the_object_name_bottom_left_corner_is_at_location(name, location):
 @then(parsers.parse('the object "{name}" is contained in "{container_name}"'))
 def the_object_name_is_contained_in_container_name(name, container_name):
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     container = ifcopenshell.util.element.get_container(element)
     if not container:
         assert False, f'Object "{name}" is not in any container'
@@ -1179,7 +1180,7 @@ def the_object_name_is_contained_in_container_name(name, container_name):
 @then(parsers.parse('the object "{name}" is contained in object "{container_name}"'))
 def the_object_name_is_contained_in_object_container_name(name: str, container_name: str) -> None:
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     container = ifcopenshell.util.element.get_container(element)
     if not container:
         assert False, f'Object "{name}" is not in any container'
@@ -1190,7 +1191,7 @@ def the_object_name_is_contained_in_object_container_name(name: str, container_n
 @then(parsers.parse('the object "{name}" is aggregated by object "{aggregate_name}"'))
 def the_object_name_is_aggregated_by_object_aggregate_name(name: str, aggregate_name: str) -> None:
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     aggregate = ifcopenshell.util.element.get_aggregate(element)
     if not aggregate:
         assert False, f'Object "{name}" is not aggregated by any element'
@@ -1201,7 +1202,7 @@ def the_object_name_is_aggregated_by_object_aggregate_name(name: str, aggregate_
 @then(parsers.parse('the object "{name}" has no aggregate'))
 def the_object_name_has_no_aggregate(name: str) -> None:
     ifc = an_ifc_file_exists()
-    element = ifc.by_id(the_object_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    element = ifc.by_id(tool.Blender.get_ifc_definition_id(the_object_name_exists(name)))
     aggregate = ifcopenshell.util.element.get_aggregate(element)
     if aggregate:
         assert False, f'Object "{name}" is aggregated by element "{aggregate}"'

src/bonsai/test/tool/test_collector.py

@@ -19,6 +19,7 @@
 import bpy
 import ifcopenshell
 import ifcopenshell.api
+import ifcopenshell.api.aggregate
 import ifcopenshell.util.element
 import bonsai.core.tool
 import bonsai.tool as tool
@@ -167,7 +168,8 @@ class TestAssign(NewIfc):
         tool.Ifc.link(building_element, building_obj)
         building_collection = bpy.data.collections.new("Foobar")
         bpy.context.scene.collection.children.link(building_collection)
-        building_obj.BIMObjectProperties.collection = building_collection
+        props = tool.Blender.get_object_bim_props(building_obj)
+        props.collection = building_collection
         building_collection.objects.link(building_obj)
         ifcopenshell.api.aggregate.assign_object(
             tool.Ifc.get(),

src/bonsai/test/tool/test_drawing.py

@@ -319,7 +319,8 @@ class TestGetDrawingCollection(NewFile):
         collection = bpy.data.collections.new("Collection")
         bpy.context.scene.collection.children.link(collection)
         collection.objects.link(obj)
-        obj.BIMObjectProperties.collection = collection
+        props = tool.Blender.get_object_bim_props(obj)
+        props.collection = collection
         collection.BIMCollectionProperties.obj = obj
 
         element = ifc.createIfcAnnotation()

src/bonsai/test/tool/test_geometry.py

@@ -170,22 +170,25 @@ class TestGetTextLiteral(NewFile):
 class TestGetCartesianPointCoordinateOffset(NewFile):
     def test_run(self):
         obj = bpy.data.objects.new("Object", None)
-        obj.BIMObjectProperties.blender_offset_type = "CARTESIAN_POINT"
+        oprops = tool.Blender.get_object_bim_props(obj)
+        oprops.blender_offset_type = "CARTESIAN_POINT"
         props = tool.Georeference.get_georeference_props()
         props.has_blender_offset = True
-        obj.BIMObjectProperties.cartesian_point_offset = "1,2,3"
+        oprops.cartesian_point_offset = "1,2,3"
         assert np.allclose(subject.get_cartesian_point_offset(obj), np.array((1.0, 2.0, 3.0)))
 
     def test_get_null_if_not_a_cartesian_point_offset_type(self):
         obj = bpy.data.objects.new("Object", None)
         props = tool.Georeference.get_georeference_props()
         props.has_blender_offset = True
-        obj.BIMObjectProperties.cartesian_point_offset = "1,2,3"
+        oprops = tool.Blender.get_object_bim_props(obj)
+        oprops.cartesian_point_offset = "1,2,3"
         assert subject.get_cartesian_point_offset(obj) is None
 
     def test_get_null_if_no_blender_offset(self):
         obj = bpy.data.objects.new("Object", None)
-        obj.BIMObjectProperties.blender_offset_type = "CARTESIAN_POINT"
+        oprops = tool.Blender.get_object_bim_props(obj)
+        oprops.blender_offset_type = "CARTESIAN_POINT"
         props = tool.Georeference.get_georeference_props()
         props.has_blender_offset = False
         assert subject.get_cartesian_point_offset(obj) is None
@@ -307,15 +310,16 @@ class TestRecordObjectMaterials(NewFile):
         material.BIMStyleProperties.ifc_definition_id = style.id()
         obj.data.materials.append(material)
         subject.record_object_materials(obj)
-        assert tool.Geometry.get_mesh_props(obj).material_checksum == str([style.id()])
+        assert tool.Geometry.get_mesh_props(obj.data).material_checksum == str([style.id()])
 
 
 class TestRecordObjectPosition(NewFile):
     def test_run(self):
         obj = bpy.data.objects.new("Object", None)
+        props = tool.Blender.get_object_bim_props(obj)
         subject.record_object_position(obj)
-        assert obj.BIMObjectProperties.location_checksum == repr(np.array(obj.matrix_world.translation).tobytes())
+        assert props.location_checksum == repr(np.array(obj.matrix_world.translation).tobytes())
-        assert obj.BIMObjectProperties.rotation_checksum == repr(np.array(obj.matrix_world.to_3x3()).tobytes())
+        assert props.rotation_checksum == repr(np.array(obj.matrix_world.to_3x3()).tobytes())
 
 
 class TestRemoveConnection(NewFile):

src/bonsai/test/tool/test_ifc.py

@@ -129,14 +129,16 @@ class TestGetEntity(test.bim.bootstrap.NewFile):
 
     def test_attempting_without_a_file(self):
         obj = bpy.data.objects.new("Object", None)
-        obj.BIMObjectProperties.ifc_definition_id = 1
+        props = tool.Blender.get_object_bim_props(obj)
+        props.ifc_definition_id = 1
         assert subject.get_entity(obj) is None
 
     def test_attempting_to_get_an_invalidly_linked_object(self):
         ifc = ifcopenshell.file()
         subject.set(ifc)
         obj = bpy.data.objects.new("Object", None)
-        obj.BIMObjectProperties.ifc_definition_id = 1
+        props = tool.Blender.get_object_bim_props(obj)
+        props.ifc_definition_id = 1
         assert subject.get_entity(obj) is None
 
 

src/bonsai/test/tool/test_model.py

@@ -383,23 +383,26 @@ class TestUsingArrays(NewFile):
 
         bpy.ops.mesh.primitive_cube_add()
         obj = bpy.context.active_object
+        assert obj
         rprops = tool.Root.get_root_props()
         rprops.ifc_product = "IfcElement"
         bpy.ops.bim.assign_class(ifc_class="IfcActuator", predefined_type="ELECTRICACTUATOR", userdefined_type="")
 
         bpy.ops.bim.add_array()
         bpy.ops.bim.enable_editing_array(item=0)
-        obj.BIMArrayProperties.count = 4
+        props = tool.Model.get_array_props(obj)
-        obj.BIMArrayProperties.x = 4
+        props.count = 4
-        obj.BIMArrayProperties.sync_children = sync_children
+        props.x = 4
+        props.sync_children = sync_children
         bpy.ops.bim.edit_array(item=0)
 
         if add_second_layer:
             bpy.ops.bim.add_array()
             bpy.ops.bim.enable_editing_array(item=1)
-            obj.BIMArrayProperties.count = 3
+            props = tool.Model.get_array_props(obj)
-            obj.BIMArrayProperties.y = 4
+            props.count = 3
-            obj.BIMArrayProperties.sync_children = sync_children
+            props.y = 4
+            props.sync_children = sync_children
             bpy.ops.bim.edit_array(item=1)
 
     def test_remove_array_last_to_first(self):

src/bonsai/test/tool/test_surveyor.py

@@ -54,6 +54,7 @@ class TestGetGlobalMatrix(test.bim.bootstrap.NewFile):
         props.blender_x_axis_abscissa = "0"
         props.blender_x_axis_ordinate = "1"
         obj = bpy.data.objects.new("Object", None)
-        obj.BIMObjectProperties.blender_offset_type = "OBJECT_PLACEMENT"
+        props = tool.Blender.get_object_bim_props(obj)
+        props.blender_offset_type = "OBJECT_PLACEMENT"
         matrix = ifcopenshell.util.geolocation.local2global(np.array(obj.matrix_world), 1.0, 2.0, 3.0, 0.0, 1.0)
         assert (subject.get_absolute_matrix(obj) == matrix).all()

src/bonsai/test/tool/test_unit.py

@@ -240,7 +240,7 @@ class TestImportUnitAttributes(NewFile):
         assert props.unit_attributes["UnitType"].enum_value == "ABSORBEDDOSEUNIT"
         assert props.unit_attributes["Prefix"].enum_value == "EXA"
         assert props.unit_attributes["Name"].enum_value == "AMPERE"
-        assert props.unit_attributes["Dimensions"] is None
+        assert "Dimensions" not in props.unit_attributes
 
 
 class TestImportUnits(NewFile):

src/ifcopenshell-python/ifcopenshell/api/geometry/add_window_representation.py

@@ -442,7 +442,7 @@ class Usecase:
 
         panel_schema: list[list[int]] = self.settings["panel_schema"]
         panels: list[dict[str, Any]] = self.settings["panel_properties"]
-        accumulated_height = [0] * len(panel_schema[0])
+        accumulated_height: list[float] = [0] * len(panel_schema[0])
         built_panels: list[int] = []
         window_items: list[ifcopenshell.entity_instance] = []
         lining_items: list[ifcopenshell.entity_instance] = []

src/ifcpatch/ifcpatch/recipes/FixRevitTINs.py

@@ -96,7 +96,8 @@ class Patcher:
         angle_threshold = 0.3
 
         for obj in bpy.data.objects:
-            if not obj.BIMObjectProperties.ifc_definition_id or not obj.data:
+            ifc_id = tool.Blender.get_ifc_definition_id(obj)
+            if not ifc_id or not obj.data:
                 continue
             if not obj.data.polygons:
                 continue