typing

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

@@ -380,7 +380,7 @@ class BIM_PT_object_qtos(Panel):
                     filter_keyword=context.scene.GlobalPsetProperties.qto_filter,
                 )
         layout = self.layout
-        qtoprops = context.scene.BIMQtoProperties
+        qtoprops = tool.Qto.get_qto_props()
         row = layout.row(align=True)
         row.prop(qtoprops, "qto_rule", text="")
         # A bit confusing as we typically use this icon for is_null.

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

@@ -76,6 +76,7 @@ def get_length(o: bpy.types.Object, vg_index: Optional[int] = None) -> float:
             return max(y, z)
 
     length = 0
+    assert isinstance(o.data, bpy.types.Mesh)
     edges = [
         e
         for e in o.data.edges
@@ -269,6 +270,7 @@ def get_net_perimeter(o: bpy.types.Object) -> float:
 
 def get_gross_perimeter(o: bpy.types.Object) -> float:
     element = tool.Ifc.get_entity(o)
+    assert element
     mesh = get_gross_element_mesh(element)
     gross_obj = bpy.data.objects.new("GrossObj", mesh)
     gross_perimeter = get_net_perimeter(gross_obj)
@@ -420,6 +422,7 @@ def get_gross_footprint_area(o: bpy.types.Object) -> float:
         return get_net_footprint_area(o)
 
     element = tool.Ifc.get_entity(o)
+    assert element
     mesh = get_gross_element_mesh(element)
     gross_obj = bpy.data.objects.new("GrossObj", mesh)
     gross_footprint_area = get_net_footprint_area(gross_obj)
@@ -474,6 +477,7 @@ def get_gross_surface_area(o: bpy.types.Object, vg_index: Optional[int] = None)
             return get_net_surface_area(o)
 
         element = tool.Ifc.get_entity(o)
+        assert element
         mesh = get_gross_element_mesh(element)
         area = get_mesh_area(mesh)
         bpy.data.meshes.remove(mesh)
@@ -506,6 +510,7 @@ def is_polygon_in_vg(polygon: bpy.types.MeshPolygon, vertices_in_vg: list[bpy.ty
 
 
 def get_net_volume(o: bpy.types.Object) -> float:
+    assert isinstance(o.data, bpy.types.Mesh)
     o_mesh = bmesh.new()
     o_mesh.from_mesh(o.data)
     volume = o_mesh.calc_volume()
@@ -518,6 +523,7 @@ def get_gross_volume(o: bpy.types.Object) -> float:
         return get_net_volume(o)
 
     element = tool.Ifc.get_entity(o)
+    assert element
     mesh = get_gross_element_mesh(element)
     bm = get_bmesh_from_mesh(mesh)
 
@@ -562,6 +568,7 @@ def get_net_weight(obj: bpy.types.Object) -> Union[float, None]:
 
 def get_obj_mass_density(obj: bpy.types.Object) -> Union[float, None]:
     entity = tool.Ifc.get_entity(obj)
+    assert entity
     material = ifcopenshell.util.element.get_material(entity)
     if material is None:
         return
@@ -764,6 +771,7 @@ def get_outer_surface_area(obj: bpy.types.Object) -> float:
 
 def get_end_area(obj: bpy.types.Object) -> float:
     element = tool.Ifc.get_entity(obj)
+    assert element
     gross_mesh = get_gross_element_mesh(element)
     gross_obj = bpy.data.objects.new("MyObject", gross_mesh)
 

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

@@ -51,6 +51,7 @@ def calculate_mesh_quantity(
     result = 0
     edit_mode = context.active_object.mode == "EDIT"
     for obj in objs:
+        assert isinstance(obj.data, bpy.types.Mesh)
         if edit_mode:
             bm = bmesh.from_edit_mesh(obj.data)
             result += operation(bm)

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

@@ -49,7 +49,7 @@ class CalculateEdgeLengths(bpy.types.Operator):
 
     def execute(self, context):
         result = helper.calculate_edges_lengths([o for o in context.selected_objects if o.type == "MESH"], context)
-        context.scene.BIMQtoProperties.qto_result = str(round(result, 3))
+        tool.Qto.set_qto_result(result)
         return {"FINISHED"}
 
 
@@ -64,7 +64,7 @@ class CalculateFaceAreas(bpy.types.Operator):
 
     def execute(self, context):
         result = helper.calculate_faces_areas([o for o in context.selected_objects if o.type == "MESH"], context)
-        context.scene.BIMQtoProperties.qto_result = str(round(result, 3))
+        tool.Qto.set_qto_result(result)
         return {"FINISHED"}
 
 
@@ -79,7 +79,7 @@ class CalculateObjectVolumes(bpy.types.Operator):
 
     def execute(self, context):
         result = helper.calculate_volumes([o for o in context.selected_objects if o.type == "MESH"], context)
-        context.scene.BIMQtoProperties.qto_result = str(round(result, 3))
+        tool.Qto.set_qto_result(result)
         return {"FINISHED"}
 
 
@@ -94,7 +94,7 @@ class CalculateFormworkArea(bpy.types.Operator):
 
     def execute(self, context):
         result = helper.calculate_formwork_area([o for o in context.selected_objects if o.type == "MESH"], context)
-        context.scene.BIMQtoProperties.qto_result = str(round(result, 3))
+        tool.Qto.set_qto_result(result)
         return {"FINISHED"}
 
 
@@ -109,7 +109,7 @@ class CalculateSideFormworkArea(bpy.types.Operator):
 
     def execute(self, context):
         result = helper.calculate_side_formwork_area([o for o in context.selected_objects if o.type == "MESH"], context)
-        context.scene.BIMQtoProperties.qto_result = str(round(result, 3))
+        tool.Qto.set_qto_result(result)
         return {"FINISHED"}
 
 
@@ -126,7 +126,7 @@ class CalculateSingleQuantity(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         import ifc5d.qto
 
-        props = context.scene.BIMQtoProperties
+        props = tool.Qto.get_qto_props()
         elements = set()
         for obj in tool.Blender.get_selected_objects(include_active=False):
             element = tool.Ifc.get_entity(obj)
@@ -163,7 +163,7 @@ class PerformQuantityTakeOff(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         import ifc5d.qto
 
-        props = context.scene.BIMQtoProperties
+        props = tool.Qto.get_qto_props()
 
         elements: set[ifcopenshell.entity_instance]
         if context.selected_objects:

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

@@ -31,12 +31,16 @@ from bpy.props import (
     FloatVectorProperty,
     CollectionProperty,
 )
+from typing import TYPE_CHECKING, Union
 
 
-def get_qto_rule(self, context):
+CALCULATOR_FUNCTION_ENUM_ITEMS: list[Union[tuple[str, str, str], None]] = []
+
+
+def get_qto_rule(self: "BIMQtoProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
     ifc_file = tool.Ifc.get()
     is_ifc4x3 = ifc_file.schema == "IFC4X3"
-    results = []
+    results: list[tuple[str, str, str]] = []
     for rule_id, rule in ifc5d.qto.rules.items():
         if rule_id.startswith("IFC4X3") != is_ifc4x3:
             continue
@@ -44,14 +48,16 @@ def get_qto_rule(self, context):
     return results
 
 
-def get_calculator(self, context):
-    results = []
+def get_calculator(self: "BIMQtoProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
+    results: list[tuple[str, str, str]] = []
     for name, calculator in ifc5d.qto.calculators.items():
-        results.append((name, name, calculator.__doc__))
+        results.append((name, name, calculator.__doc__ or ""))
     return results
 
 
-def get_calculator_function(self, context):
+def get_calculator_function(
+    self: "BIMQtoProperties", context: bpy.types.Context
+) -> list[Union[tuple[str, str, str], None]]:
     global CALCULATOR_FUNCTION_ENUM_ITEMS
     calculator = ifc5d.qto.calculators[self.calculator]
     CALCULATOR_FUNCTION_ENUM_ITEMS = []
@@ -60,6 +66,8 @@ def get_calculator_function(self, context):
         measure = function.measure.split("Measure")[0][3:]
         if previous_measure is not None and measure != previous_measure:
             CALCULATOR_FUNCTION_ENUM_ITEMS.append(None)
+        description = function.description
+        description += f"\n\nInternal function id: '{function_id}'."
         CALCULATOR_FUNCTION_ENUM_ITEMS.append((function_id, f"{measure}: {function.name}", function.description))
         previous_measure = measure
     return CALCULATOR_FUNCTION_ENUM_ITEMS
@@ -80,3 +88,12 @@ class BIMQtoProperties(PropertyGroup):
         ),
         default=False,
     )
+
+    if TYPE_CHECKING:
+        qto_rule: str
+        calculator: str
+        calculator_function: str
+        qto_result: str
+        qto_name: str
+        prop_name: str
+        fallback: bool

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

@@ -17,6 +17,7 @@
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
 import bpy
+import bonsai.tool as tool
 from bonsai.bim.module.qto.data import QtoData
 
 
@@ -32,7 +33,7 @@ class BIM_PT_qto(bpy.types.Panel):
 
     def draw(self, context):
         layout = self.layout
-        props = context.scene.BIMQtoProperties
+        props = tool.Qto.get_qto_props()
 
         row = layout.row()
         if context.selected_objects:
@@ -57,7 +58,7 @@ class BIM_PT_qto_manual(bpy.types.Panel):
 
     def draw(self, context):
         layout = self.layout
-        props = context.scene.BIMQtoProperties
+        props = tool.Qto.get_qto_props()
 
         row = layout.row()
         row.prop(props, "calculator")
@@ -83,7 +84,7 @@ class BIM_PT_qto_simple(bpy.types.Panel):
 
     def draw(self, context):
         layout = self.layout
-        props = context.scene.BIMQtoProperties
+        props = tool.Qto.get_qto_props()
 
         row = layout.row()
         row.prop(props, "qto_result", text="Results")

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

@@ -59,7 +59,7 @@ class LoadGroupDecorationData:
             return ret
 
         m = models[0]
-        props = bpy.context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         if props.activity_type == "Action":
             groups = m.LoadedBy or []
             for g in groups:
@@ -128,7 +128,8 @@ class ConnectedStructuralMembersData:
         if not element:
             return []
         results = []
-        props = bpy.context.active_object.BIMStructuralProperties
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
         for rel in element.ConnectsStructuralMembers or []:
             condition = rel.AppliedCondition
             if condition:
@@ -257,7 +258,7 @@ class StructuralLoadCasesData:
 
     @classmethod
     def applicable_structural_loads(cls):
-        props = bpy.context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         results = []
         for load in tool.Ifc.get().by_type("IfcStructuralLoad"):
             if not load.Name or not load.is_a(props.applicable_structural_load_types):

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

@@ -24,6 +24,7 @@ from mathutils import Vector
 import ifcopenshell
 import ifcopenshell.api
 import ifcopenshell.util.attribute
+import ifcopenshell.util.placement
 import ifcopenshell.util.unit as ifcunit
 import bonsai.tool as tool
 from bonsai.bim.module.structural.shader import DecorationShader
@@ -304,7 +305,7 @@ class ShaderInfo:
                                         populate_members_dict("surface_members", element, activity, factor)
                     recursive_subgroups(subgorups, rec_limit - 1, activity_type, factor=factor)
 
-        props = bpy.context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         group_definition_id = int(props.load_group_to_show)
         file = tool.Ifc.get()
         groups = [file.by_id(group_definition_id)]
@@ -327,7 +328,7 @@ class ShaderInfo:
                 maximum = max([abs(float(i)) for i in values])
                 if maximum == 0:
                     continue
-            props = bpy.context.scene.BIMStructuralProperties
+            props = tool.Structural.get_structural_props()
             reference_frame = props.reference_frame
             orientation = np.eye(3)
             if reference_frame == "LOCAL_COORDS":
@@ -435,7 +436,7 @@ class ShaderInfo:
     ) -> np.ndarray:
         "provides the transformation matrix to convert between reference frames"
         global_or_local = activity.GlobalOrLocal
-        props = bpy.context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         reference_frame = props.reference_frame
         transform_matrix = np.eye(3)
         if reference_frame == "LOCAL_COORDS" and global_or_local != reference_frame:
@@ -473,7 +474,7 @@ class ShaderInfo:
             "mz": (np.array((1, 0, 0)), np.array((0, 1, 0))),
         }
         keys = ["fx", "fy", "fz", "mx", "my", "mz"]
-        props = bpy.context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         reference_frame = props.reference_frame
         if reference_frame == "LOCAL_COORDS":
             for key in keys:
@@ -591,7 +592,7 @@ class ShaderInfo:
             z_axis = x_axis.cross(y_axis).normalized()
             rotation = self.get_curve_member_rotation(member)
 
-            props = bpy.context.scene.BIMStructuralProperties
+            props = tool.Structural.get_structural_props()
             reference_frame = props.reference_frame
             is_local = reference_frame == "LOCAL_COORDS"
             x_match = abs(Vector((1, 0, 0)).dot(x_axis)) > 0.99

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

@@ -20,6 +20,7 @@ import bpy
 import json
 import ifcopenshell
 import ifcopenshell.api
+import ifcopenshell.api.group
 import ifcopenshell.api.structural
 import ifcopenshell.util.attribute
 import bonsai.bim.helper
@@ -77,7 +78,7 @@ class AddStructuralMemberConnection(bpy.types.Operator, tool.Ifc.Operator):
         obj = context.active_object
         assert obj
         oprops = tool.Blender.get_object_bim_props(obj)
-        props = obj.BIMStructuralProperties
+        props = tool.Structural.get_object_structural_props(obj)
         file = tool.Ifc.get()
         related_structural_connection = file.by_id(oprops.ifc_definition_id)
         relating_structural_member = tool.Ifc.get_entity(props.relating_structural_member)
@@ -101,7 +102,8 @@ class EnableEditingStructuralConnectionCondition(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMStructuralProperties
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
         props.active_connects_structural_member = self.connects_structural_member
         return {"FINISHED"}
 
@@ -113,7 +115,8 @@ class DisableEditingStructuralConnectionCondition(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMStructuralProperties
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
         props.active_connects_structural_member = 0
         return {"FINISHED"}
 
@@ -166,7 +169,8 @@ class EnableEditingStructuralBoundaryCondition(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMStructuralProperties
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
         props.boundary_condition_attributes.clear()
 
         condition = tool.Ifc.get().by_id(self.boundary_condition)
@@ -206,7 +210,8 @@ class EditStructuralBoundaryCondition(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         obj = context.active_object
-        props = obj.BIMStructuralProperties
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
 
         file = tool.Ifc.get()
         connection = file.by_id(self.connection)
@@ -236,7 +241,10 @@ class DisableEditingStructuralBoundaryCondition(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        context.active_object.BIMStructuralProperties.active_boundary_condition = 0
+        obj = context.active_object
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
+        props.active_boundary_condition = 0
         return {"FINISHED"}
 
 
@@ -353,7 +361,7 @@ class EnableEditingStructuralItemAxis(bpy.types.Operator):
         obj = context.active_object
         assert obj
         oprops = tool.Blender.get_object_bim_props(obj)
-        props = obj.BIMStructuralProperties
+        props = tool.Structural.get_object_structural_props(obj)
 
         self.file = tool.Ifc.get()
         item = self.file.by_id(oprops.ifc_definition_id)
@@ -392,7 +400,8 @@ class DisableEditingStructuralItemAxis(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMStructuralProperties
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
         props.is_editing_axis = False
         if props.axis_empty:
             bpy.data.objects.remove(props.axis_empty)
@@ -407,7 +416,7 @@ class EditStructuralItemAxis(bpy.types.Operator, tool.Ifc.Operator):
         obj = context.active_object
         assert obj
         oprops = tool.Blender.get_object_bim_props(obj)
-        props = obj.BIMStructuralProperties
+        props = tool.Structural.get_object_structural_props(obj)
         relative_matrix = props.axis_empty.matrix_world @ obj.matrix_world.inverted()
         z_axis = relative_matrix.col[2][0:3]
         self.file = tool.Ifc.get()
@@ -429,7 +438,7 @@ class EnableEditingStructuralConnectionCS(bpy.types.Operator):
     def execute(self, context):
         obj = context.active_object
         assert obj
-        props = obj.BIMStructuralProperties
+        props = tool.Structural.get_object_structural_props(obj)
 
         self.file = tool.Ifc.get()
         item = tool.Ifc.get_entity(obj)
@@ -481,7 +490,8 @@ class DisableEditingStructuralConnectionCS(bpy.types.Operator):
 
     def execute(self, context):
         obj = context.active_object
-        props = obj.BIMStructuralProperties
+        assert obj
+        props = tool.Structural.get_object_structural_props(obj)
         props.is_editing_connection_cs = False
         if props.ccs_empty:
             bpy.data.objects.remove(props.ccs_empty)
@@ -498,7 +508,7 @@ class EditStructuralConnectionCS(bpy.types.Operator, tool.Ifc.Operator):
         assert obj
         item = tool.Ifc.get_entity(obj)
         assert item
-        props = obj.BIMStructuralProperties
+        props = tool.Structural.get_object_structural_props(obj)
         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]
@@ -567,13 +577,13 @@ class EditStructuralLoadCase(bpy.types.Operator, tool.Ifc.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         attributes = bonsai.bim.helper.export_attributes(props.load_case_attributes)
         self.file = tool.Ifc.get()
-        ifcopenshell.api.run(
-            "structural.edit_structural_load_case",
+        ifcopenshell.api.structural.edit_structural_load_case(
             self.file,
-            **{"load_case": self.file.by_id(props.active_load_case_id), "attributes": attributes},
+            load_case=self.file.by_id(props.active_load_case_id),
+            attributes=attributes,
         )
         bpy.ops.bim.disable_editing_structural_load_case()
         return {"FINISHED"}
@@ -587,9 +597,7 @@ class RemoveStructuralLoadCase(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         self.file = tool.Ifc.get()
-        ifcopenshell.api.run(
-            "structural.remove_structural_load_case", self.file, load_case=self.file.by_id(self.load_case)
-        )
+        ifcopenshell.api.structural.remove_structural_load_case(self.file, load_case=self.file.by_id(self.load_case))
         return {"FINISHED"}
 
 
@@ -600,7 +608,7 @@ class EnableEditingStructuralLoadCase(bpy.types.Operator):
     load_case: bpy.props.IntProperty()
 
     def execute(self, context):
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
         self.props.active_load_case_id = self.load_case
         self.props.load_case_editing_type = "ATTRIBUTES"
         self.props.load_case_attributes.clear()
@@ -620,7 +628,8 @@ class DisableEditingStructuralLoadCase(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        context.scene.BIMStructuralProperties.active_load_case_id = 0
+        props = tool.Structural.get_structural_props()
+        props.active_load_case_id = 0
         return {"FINISHED"}
 
 
@@ -631,9 +640,9 @@ class EnableEditingStructuralLoadCaseGroups(bpy.types.Operator):
     load_case: bpy.props.IntProperty()
 
     def execute(self, context):
-        self.props = context.scene.BIMStructuralProperties
-        self.props.active_load_case_id = self.load_case
-        self.props.load_case_editing_type = "GROUPS"
+        props = tool.Structural.get_structural_props()
+        props.active_load_case_id = self.load_case
+        props.load_case_editing_type = "GROUPS"
         return {"FINISHED"}
 
 
@@ -645,10 +654,8 @@ class AddStructuralLoadGroup(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         self.file = tool.Ifc.get()
-        load_group = ifcopenshell.api.run("structural.add_structural_load_group", self.file)
-        ifcopenshell.api.run(
-            "group.assign_group", self.file, products=[load_group], group=self.file.by_id(self.load_case)
-        )
+        load_group = ifcopenshell.api.structural.add_structural_load_group(self.file)
+        ifcopenshell.api.group.assign_group(self.file, products=[load_group], group=self.file.by_id(self.load_case))
         return {"FINISHED"}
 
 
@@ -660,9 +667,7 @@ class RemoveStructuralLoadGroup(bpy.types.Operator, tool.Ifc.Operator):
 
     def _execute(self, context):
         self.file = tool.Ifc.get()
-        ifcopenshell.api.run(
-            "structural.remove_structural_load_group", self.file, load_group=self.file.by_id(self.load_group)
-        )
+        ifcopenshell.api.structural.remove_structural_load_group(self.file, load_group=self.file.by_id(self.load_group))
         return {"FINISHED"}
 
 
@@ -674,15 +679,15 @@ class EnableEditingStructuralLoadGroupActivities(bpy.types.Operator):
 
     def execute(self, context):
         self.file = tool.Ifc.get()
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
         self.props.active_load_group_id = self.load_group
         self.props.load_group_editing_type = "ACTIVITY"
         self.load_structural_activities()
         return {"FINISHED"}
 
-    def load_structural_activities(self):
+    def load_structural_activities(self) -> None:
         self.props.load_group_activities.clear()
-        for rel in tool.Ifc.get().by_id(self.load_group).IsGroupedBy:
+        for rel in self.file.by_id(self.load_group).IsGroupedBy:
             for activity in rel.RelatedObjects:
                 new = self.props.load_group_activities.add()
                 new.ifc_definition_id = activity.id()
@@ -697,7 +702,7 @@ class AddStructuralActivity(bpy.types.Operator, tool.Ifc.Operator):
     load_group: bpy.props.IntProperty()
 
     def _execute(self, context):
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
         self.file = tool.Ifc.get()
         for obj in context.selected_objects:
             element = tool.Ifc.get_entity(obj)
@@ -726,16 +731,13 @@ class AddStructuralActivity(bpy.types.Operator, tool.Ifc.Operator):
 
             ifc_class = applicable_activity_class[element.is_a()]
 
-            activity = ifcopenshell.api.run(
-                "structural.add_structural_activity",
+            activity = ifcopenshell.api.structural.add_structural_activity(
                 self.file,
                 ifc_class=ifc_class,
                 applied_load=self.file.by_id(int(self.props.applicable_structural_loads)),
                 structural_member=element,
             )
-            ifcopenshell.api.run(
-                "group.assign_group", self.file, products=[activity], group=self.file.by_id(self.load_group)
-            )
+            ifcopenshell.api.group.assign_group(self.file, products=[activity], group=self.file.by_id(self.load_group))
         bpy.ops.bim.enable_editing_structural_load_group_activities(load_group=self.load_group)
         return {"FINISHED"}
 
@@ -747,7 +749,7 @@ class LoadStructuralLoads(bpy.types.Operator):
 
     def execute(self, context):
         self.file = tool.Ifc.get()
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         props.structural_loads.clear()
         loads = tool.Ifc.get().by_type("IfcStructuralLoad")
         if props.filtered_structural_loads:
@@ -780,7 +782,8 @@ class DisableStructuralLoadEditingUI(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        context.scene.BIMStructuralProperties.is_editing_loads = False
+        props = tool.Structural.get_structural_props()
+        props.is_editing_loads = False
         return {"FINISHED"}
 
 
@@ -806,7 +809,7 @@ class EnableEditingStructuralLoad(bpy.types.Operator):
     structural_load: bpy.props.IntProperty()
 
     def execute(self, context):
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         props.structural_load_attributes.clear()
         bonsai.bim.helper.import_attributes2(
             tool.Ifc.get().by_id(self.structural_load), props.structural_load_attributes
@@ -821,7 +824,8 @@ class DisableEditingStructuralLoad(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        context.scene.BIMStructuralProperties.active_structural_load_id = 0
+        props = tool.Structural.get_structural_props()
+        props.active_structural_load_id = 0
         return {"FINISHED"}
 
 
@@ -832,12 +836,10 @@ class RemoveStructuralLoad(bpy.types.Operator, tool.Ifc.Operator):
     structural_load: bpy.props.IntProperty()
 
     def _execute(self, context):
-        props = context.scene.BIMStructuralProperties
         self.file = tool.Ifc.get()
-        ifcopenshell.api.run(
-            "structural.remove_structural_load",
+        ifcopenshell.api.structural.remove_structural_load(
             self.file,
-            **{"structural_load": self.file.by_id(self.structural_load)},
+            structural_load=self.file.by_id(self.structural_load),
         )
         bpy.ops.bim.load_structural_loads()
         return {"FINISHED"}
@@ -849,16 +851,13 @@ class EditStructuralLoad(bpy.types.Operator, tool.Ifc.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         attributes = bonsai.bim.helper.export_attributes(props.structural_load_attributes)
         self.file = tool.Ifc.get()
-        ifcopenshell.api.run(
-            "structural.edit_structural_load",
+        ifcopenshell.api.structural.edit_structural_load(
             self.file,
-            **{
-                "structural_load": self.file.by_id(props.active_structural_load_id),
-                "attributes": attributes,
-            },
+            structural_load=self.file.by_id(props.active_structural_load_id),
+            attributes=attributes,
         )
         bpy.ops.bim.load_structural_loads()
         return {"FINISHED"}
@@ -870,7 +869,7 @@ class ToggleFilterStructuralLoads(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         props.filtered_structural_loads = not props.filtered_structural_loads
         bpy.ops.bim.load_structural_loads()
         return {"FINISHED"}
@@ -883,7 +882,7 @@ class LoadBoundaryConditions(bpy.types.Operator):
 
     def execute(self, context):
         self.file = tool.Ifc.get()
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         props.boundary_conditions.clear()
         conditions = tool.Ifc.get().by_type("IfcBoundaryCondition")
         if props.filtered_boundary_conditions:
@@ -916,7 +915,7 @@ class ToggleFilterBoundaryConditions(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         props.filtered_boundary_conditions = not props.filtered_boundary_conditions
         bpy.ops.bim.load_boundary_conditions()
         return {"FINISHED"}
@@ -928,7 +927,8 @@ class DisableBoundaryConditionEditingUI(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        context.scene.BIMStructuralProperties.is_editing_boundary_conditions = False
+        props = tool.Structural.get_structural_props()
+        props.is_editing_boundary_conditions = False
         return {"FINISHED"}
 
 
@@ -939,8 +939,7 @@ class AddBoundaryCondition(bpy.types.Operator, tool.Ifc.Operator):
     ifc_class: bpy.props.StringProperty()
 
     def _execute(self, context):
-        result = ifcopenshell.api.run(
-            "structural.add_structural_boundary_condition",
+        result = ifcopenshell.api.structural.add_structural_boundary_condition(
             tool.Ifc.get(),
             name="New Load",
             ifc_class=self.ifc_class,
@@ -957,7 +956,7 @@ class EnableEditingBoundaryCondition(bpy.types.Operator):
     boundary_condition: bpy.props.IntProperty()
 
     def execute(self, context):
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         props.boundary_condition_attributes.clear()
 
         boundary_condition = tool.Ifc.get().by_id(self.boundary_condition)
@@ -994,7 +993,8 @@ class DisableEditingBoundaryCondition(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        context.scene.BIMStructuralProperties.active_boundary_condition_id = 0
+        props = tool.Structural.get_structural_props()
+        props.active_boundary_condition_id = 0
         return {"FINISHED"}
 
 
@@ -1005,12 +1005,10 @@ class RemoveBoundaryCondition(bpy.types.Operator, tool.Ifc.Operator):
     boundary_condition: bpy.props.IntProperty()
 
     def _execute(self, context):
-        props = context.scene.BIMStructuralProperties
         self.file = tool.Ifc.get()
-        ifcopenshell.api.run(
-            "structural.remove_structural_boundary_condition",
+        ifcopenshell.api.structural.remove_structural_boundary_condition(
             self.file,
-            **{"boundary_condition": self.file.by_id(self.boundary_condition)},
+            boundary_condition=self.file.by_id(self.boundary_condition),
         )
         bpy.ops.bim.load_boundary_conditions()
         return {"FINISHED"}
@@ -1022,7 +1020,7 @@ class EditBoundaryCondition(bpy.types.Operator, tool.Ifc.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        props = context.scene.BIMStructuralProperties
+        props = tool.Structural.get_structural_props()
         self.file = tool.Ifc.get()
         # attributes = bonsai.bim.helper.export_attributes(props.boundary_condition_attributes)
         attributes = {}
@@ -1035,10 +1033,10 @@ class EditBoundaryCondition(bpy.types.Operator, tool.Ifc.Operator):
                 attributes[attribute.name] = {"value": attribute.bool_value, "type": attribute.enum_value}
             else:
                 attributes[attribute.name] = {"value": attribute.float_value, "type": attribute.enum_value}
-        ifcopenshell.api.run(
-            "structural.edit_structural_boundary_condition",
+        ifcopenshell.api.structural.edit_structural_boundary_condition(
             self.file,
-            **{"condition": self.file.by_id(props.active_boundary_condition_id), "attributes": attributes},
+            condition=self.file.by_id(props.active_boundary_condition_id),
+            attributes=attributes,
         )
         bpy.ops.bim.load_boundary_conditions()
         return {"FINISHED"}

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

@@ -37,52 +37,62 @@ from bpy.props import (
     FloatVectorProperty,
     CollectionProperty,
 )
+from typing import TYPE_CHECKING, Union
 
 
-def get_load_groups_to_show(self, context):
+def get_load_groups_to_show(self: "BIMStructuralProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
     if not LoadGroupDecorationData.is_loaded:
         LoadGroupDecorationData.load()
     return LoadGroupDecorationData.data["load_groups_to_show"]
 
 
-def update_activity_type(self, context):
+def update_activity_type(self: "BIMStructuralProperties", context: bpy.types.Context) -> None:
     LoadGroupDecorationData.is_loaded = False
 
 
-def get_applicable_structural_load_types(self, context):
+def get_applicable_structural_load_types(
+    self: "BIMStructuralProperties", context: bpy.types.Context
+) -> list[tuple[str, str, str]]:
     if not StructuralLoadCasesData.is_loaded:
         StructuralLoadCasesData.load()
     return StructuralLoadCasesData.data["applicable_structural_load_types"]
 
 
-def updateApplicableStructuralLoadTypes(self, context):
+def updateApplicableStructuralLoadTypes(self: "BIMStructuralProperties", context: bpy.types.Context) -> None:
     StructuralLoadCasesData.data["applicable_structural_load_types"] = (
         StructuralLoadCasesData.applicable_structural_load_types()
     )
 
 
-def get_applicable_structural_loads(self, context):
+def get_applicable_structural_loads(
+    self: "BIMStructuralProperties", context: bpy.types.Context
+) -> list[tuple[str, str, str]]:
     if not StructuralLoadCasesData.is_loaded:
         StructuralLoadCasesData.load()
     return StructuralLoadCasesData.data["applicable_structural_loads"]
 
 
-def get_structural_load_types(self, context):
+def get_structural_load_types(
+    self: "BIMStructuralProperties", context: bpy.types.Context
+) -> list[tuple[str, str, str]]:
     if not StructuralLoadsData.is_loaded:
         StructuralLoadsData.load()
     return StructuralLoadsData.data["structural_load_types"]
 
 
-def get_boundary_condition_types(self, context):
+def get_boundary_condition_types(
+    self: "BIMStructuralProperties", context: bpy.types.Context
+) -> list[tuple[str, str, str]]:
     if not BoundaryConditionsData.is_loaded:
         BoundaryConditionsData.load()
     return BoundaryConditionsData.data["boundary_condition_types"]
 
 
-def updateAxisAngle(self, context):
+def updateAxisAngle(self: "BIMObjectStructuralProperties", context: bpy.types.Context) -> None:
     if not self.axis_empty:
         return
     obj = context.active_object
+    assert obj and isinstance(obj.data, bpy.types.Mesh)
     empty = self.axis_empty
     x_axis = obj.data.vertices[1].co - obj.data.vertices[0].co
     empty.location = obj.data.vertices[0].co
@@ -92,10 +102,11 @@ def updateAxisAngle(self, context):
     empty.rotation_euler[0] = radians(self.axis_angle)
 
 
-def updateConnectionCS(self, context):
+def updateConnectionCS(self: "BIMObjectStructuralProperties", context: bpy.types.Context) -> None:
     if not self.ccs_empty:
         return
     obj = context.active_object
+    assert obj and isinstance(obj.data, bpy.types.Mesh)
     empty = self.ccs_empty
     empty.location = obj.data.vertices[0].co
     empty.rotation_mode = "XYZ"
@@ -108,24 +119,39 @@ class StructuralAnalysisModel(PropertyGroup):
     name: StringProperty(name="Name")
     ifc_definition_id: IntProperty(name="IFC Definition ID")
 
+    if TYPE_CHECKING:
+        ifc_definition_id: int
+
 
 class StructuralActivity(PropertyGroup):
     name: StringProperty(name="Name")
     applied_load_class: StringProperty(name="Applied Load Class")
     ifc_definition_id: IntProperty(name="IFC Definition ID")
 
+    if TYPE_CHECKING:
+        applied_load_class: str
+        ifc_definition_id: int
+
 
 class StructuralLoad(PropertyGroup):
     name: StringProperty(name="Name")
     ifc_definition_id: IntProperty(name="IFC Definition ID")
     number_of_inverse_references: IntProperty(name="Number of Inverse References")
 
+    if TYPE_CHECKING:
+        ifc_definition_id: int
+        number_of_inverse_references: int
+
 
 class BoundaryCondition(PropertyGroup):
     name: StringProperty(name="Name")
     ifc_definition_id: IntProperty(name="IFC Definition ID")
     number_of_inverse_references: IntProperty(name="Number of Inverse References")
 
+    if TYPE_CHECKING:
+        ifc_definition_id: int
+        number_of_inverse_references: int
+
 
 class BIMStructuralProperties(PropertyGroup):
     structural_analysis_model_attributes: CollectionProperty(
@@ -187,6 +213,45 @@ class BIMStructuralProperties(PropertyGroup):
     )
     load_group_to_show: EnumProperty(items=get_load_groups_to_show, name="Load Groups")
 
+    if TYPE_CHECKING:
+        structural_analysis_model_attributes: bpy.types.bpy_prop_collection_idprop[Attribute]
+        is_editing: bool
+        structural_analysis_models: bpy.types.bpy_prop_collection_idprop[StructuralAnalysisModel]
+        active_structural_analysis_model_index: int
+        active_structural_analysis_model_id: int
+        load_case_editing_type: str
+        load_case_attributes: bpy.types.bpy_prop_collection_idprop[Attribute]
+        active_load_case_id: int
+        load_group_editing_type: str
+        active_load_group_id: int
+        applicable_structural_load_types: str
+        applicable_structural_loads: str
+        load_group_activities: bpy.types.bpy_prop_collection_idprop[StructuralActivity]
+        active_load_group_activity_index: int
+
+        structural_loads: bpy.types.bpy_prop_collection_idprop[StructuralLoad]
+        active_structural_load_index: int
+        active_structural_load_id: int
+        is_editing_loads: bool
+        structural_load_types: str
+        structural_load_attributes: bpy.types.bpy_prop_collection_idprop[Attribute]
+        filtered_structural_loads: bool
+
+        boundary_conditions: bpy.types.bpy_prop_collection_idprop[BoundaryCondition]
+        active_boundary_condition_index: int
+        active_boundary_condition_id: int
+        is_editing_boundary_conditions: bool
+        boundary_condition_types: str
+        boundary_condition_attributes: bpy.types.bpy_prop_collection_idprop[Attribute]
+        filtered_boundary_conditions: bool
+
+        show_loads: bool
+        update_load_repr: bool
+        enable_repr_auto_update: bool
+        reference_frame: str
+        activity_type: str
+        load_group_to_show: str
+
 
 class BIMObjectStructuralProperties(PropertyGroup):
     boundary_condition_attributes: CollectionProperty(name="Boundary Condition Attributes", type=Attribute)
@@ -203,3 +268,19 @@ class BIMObjectStructuralProperties(PropertyGroup):
     ccs_y_angle: FloatProperty(name="Connection CS Y Angle", update=updateConnectionCS)
     ccs_z_angle: FloatProperty(name="Connection CS Z Angle", update=updateConnectionCS)
     ccs_empty: PointerProperty(name="CCS Empty", type=bpy.types.Object)
+
+    if TYPE_CHECKING:
+        boundary_condition_attributes: bpy.types.bpy_prop_collection_idprop[Attribute]
+        active_boundary_condition: int
+        active_connects_structural_member: int
+        relating_structural_member: Union[bpy.types.Object, None]
+        is_editing_axis: bool
+        axis_angle: float
+        axis_empty: Union[bpy.types.Object, None]
+
+        # relating_structural_activity: Union[bpy.types.Object, None]
+        is_editing_connection_cs: bool
+        ccs_x_angle: float
+        ccs_y_angle: float
+        ccs_z_angle: float
+        ccs_empty: Union[bpy.types.Object, None]

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

@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import annotations
 import bpy
 import bonsai.tool as tool
 import bonsai.bim.helper
@@ -31,9 +32,25 @@ from bonsai.bim.module.structural.data import (
     StructuralConnectionData,
     BoundaryConditionsData,
 )
+from typing import TYPE_CHECKING, Any, Union
+
+if TYPE_CHECKING:
+    from bonsai.bim.module.structural.prop import (
+        BIMStructuralProperties,
+        BIMObjectStructuralProperties,
+        BoundaryCondition,
+        StructuralLoad,
+        StructuralActivity,
+        StructuralAnalysisModel,
+    )
 
 
-def draw_boundary_condition_ui(layout, boundary_condition, connection_id, props):
+def draw_boundary_condition_ui(
+    layout: bpy.types.UILayout,
+    boundary_condition: dict[str, Any],
+    connection_id: int,
+    props: BIMObjectStructuralProperties,
+) -> None:
     row = layout.row(align=True)
     if not boundary_condition:
         row.label(text="No Boundary Condition Found", icon="CON_TRACKTO")
@@ -59,11 +76,13 @@ def draw_boundary_condition_ui(layout, boundary_condition, connection_id, props)
         draw_boundary_condition_read_only_ui(layout, boundary_condition)
 
 
-def draw_boundary_condition_editable_ui(layout: bpy.types.UILayout, props: bpy.types.PropertyGroup) -> None:
+def draw_boundary_condition_editable_ui(
+    layout: bpy.types.UILayout, props: Union[BIMStructuralProperties, BIMObjectStructuralProperties]
+) -> None:
     draw_attributes(props.boundary_condition_attributes, layout)
 
 
-def draw_boundary_condition_read_only_ui(layout, boundary_condition):
+def draw_boundary_condition_read_only_ui(layout: bpy.types.UILayout, boundary_condition: dict[str, Any]) -> None:
     for attribute in boundary_condition["attributes"]:
         row = layout.row(align=True)
         row.label(text=attribute["name"])
@@ -100,11 +119,15 @@ class BIM_PT_structural_boundary_conditions(Panel):
         if not StructuralBoundaryConditionsData.is_loaded:
             StructuralBoundaryConditionsData.load()
 
+        obj = context.active_object
+        assert obj
+        self.props = tool.Structural.get_object_structural_props(obj)
+
         draw_boundary_condition_ui(
             self.layout,
             StructuralBoundaryConditionsData.data["boundary_condition"],
             StructuralBoundaryConditionsData.data["connection_id"],
-            context.active_object.BIMStructuralProperties,
+            self.props,
         )
 
 
@@ -135,7 +158,9 @@ class BIM_PT_connected_structural_members(Panel):
         if not ConnectedStructuralMembersData.is_loaded:
             ConnectedStructuralMembersData.load()
 
-        self.props = context.active_object.BIMStructuralProperties
+        obj = context.active_object
+        assert obj
+        self.props = tool.Structural.get_object_structural_props(obj)
 
         row = self.layout.row(align=True)
         row.prop(self.props, "relating_structural_member", text="", icon="CON_TRACKTO")
@@ -188,7 +213,9 @@ class BIM_PT_structural_member(Panel):
         if not StructuralMemberData.is_loaded:
             StructuralMemberData.load()
 
-        self.props = context.active_object.BIMStructuralProperties
+        obj = context.active_object
+        assert obj
+        self.props = tool.Structural.get_object_structural_props(obj)
 
         if StructuralMemberData.data["active_object_class"] == "IfcStructuralCurveMember":
             if self.props.is_editing_axis:
@@ -231,7 +258,9 @@ class BIM_PT_structural_connection(Panel):
         if not StructuralConnectionData.is_loaded:
             StructuralConnectionData.load()
 
-        self.props = context.active_object.BIMStructuralProperties
+        obj = context.active_object
+        assert obj
+        self.props = tool.Structural.get_object_structural_props(obj)
 
         if StructuralConnectionData.data["active_object_class"] == "IfcStructuralCurveConnection":
             if self.props.is_editing_axis:
@@ -281,7 +310,7 @@ class BIM_PT_structural_analysis_models(Panel):
         if not StructuralAnalysisModelsData.is_loaded:
             StructuralAnalysisModelsData.load()
 
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
 
         row = self.layout.row(align=True)
         row.label(
@@ -309,7 +338,16 @@ class BIM_PT_structural_analysis_models(Panel):
 
 
 class BIM_UL_structural_analysis_models(UIList):
-    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
+    def draw_item(
+        self,
+        context: bpy.types.Context,
+        layout: bpy.types.UILayout,
+        data: BIMStructuralProperties,
+        item: StructuralAnalysisModel,
+        icon,
+        active_data,
+        active_propname,
+    ):
         if item:
             row = layout.row(align=True)
             row.label(text=item.name)
@@ -324,10 +362,10 @@ class BIM_UL_structural_analysis_models(UIList):
                     op = row.operator("bim.assign_structural_analysis_model", text="", icon="KEYFRAME", emboss=False)
                     op.structural_analysis_model = item.ifc_definition_id
 
-            if context.scene.BIMStructuralProperties.active_structural_analysis_model_id == item.ifc_definition_id:
+            if data.active_structural_analysis_model_id == item.ifc_definition_id:
                 row.operator("bim.edit_structural_analysis_model", text="", icon="CHECKMARK")
                 row.operator("bim.disable_editing_structural_analysis_model", text="", icon="CANCEL")
-            elif context.scene.BIMStructuralProperties.active_structural_analysis_model_id:
+            elif data.active_structural_analysis_model_id:
                 op = row.operator("bim.remove_structural_analysis_model", text="", icon="X")
                 op.structural_analysis_model = item.ifc_definition_id
             else:
@@ -354,7 +392,7 @@ class BIM_PT_structural_load_cases(Panel):
         if not StructuralLoadCasesData.is_loaded:
             StructuralLoadCasesData.load()
 
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
 
         row = self.layout.row()
         row.operator("bim.add_structural_load_case", icon="ADD")
@@ -425,7 +463,16 @@ class BIM_PT_structural_load_cases(Panel):
 
 
 class BIM_UL_structural_activities(UIList):
-    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
+    def draw_item(
+        self,
+        context,
+        layout: bpy.types.UILayout,
+        data: BIMStructuralProperties,
+        item: StructuralActivity,
+        icon,
+        active_data,
+        active_propname,
+    ):
         if item:
             row = layout.row(align=True)
             row.label(text=item.name)
@@ -446,8 +493,7 @@ class BIM_PT_show_structural_activities(Panel):
         return file and hasattr(file, "schema") and file.schema != "IFC2X3"
 
     def draw(self, context):
-
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
 
         row = self.layout.row(align=True)
         row.operator(
@@ -480,7 +526,7 @@ class BIM_PT_structural_loads(Panel):
         if not StructuralLoadsData.is_loaded:
             StructuralLoadsData.load()
 
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
 
         row = self.layout.row(align=True)
         row.label(text=f"{StructuralLoadsData.data['total_loads']} Structural Loads Found", icon="ANIM_DATA")
@@ -513,16 +559,25 @@ class BIM_PT_structural_loads(Panel):
 
 
 class BIM_UL_structural_loads(UIList):
-    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
+    def draw_item(
+        self,
+        context,
+        layout: bpy.types.UILayout,
+        data: BIMStructuralProperties,
+        item: StructuralLoad,
+        icon,
+        active_data,
+        active_propname,
+    ):
         if item:
             row = layout.row(align=True)
             row.label(text=f"{item.name} ({item.number_of_inverse_references})")
             row.label(text=StructuralLoadsData.data["load_classes"][item.ifc_definition_id])
 
-            if context.scene.BIMStructuralProperties.active_structural_load_id == item.ifc_definition_id:
+            if data.active_structural_load_id == item.ifc_definition_id:
                 row.operator("bim.edit_structural_load", text="", icon="CHECKMARK")
                 row.operator("bim.disable_editing_structural_load", text="", icon="CANCEL")
-            elif context.scene.BIMStructuralProperties.active_structural_load_id:
+            elif data.active_structural_load_id:
                 op = row.operator("bim.remove_structural_load", text="", icon="X")
                 op.structural_load = item.ifc_definition_id
             else:
@@ -549,7 +604,7 @@ class BIM_PT_boundary_conditions(Panel):
         if not BoundaryConditionsData.is_loaded:
             BoundaryConditionsData.load()
 
-        self.props = context.scene.BIMStructuralProperties
+        self.props = tool.Structural.get_structural_props()
 
         row = self.layout.row(align=True)
         row.label(
@@ -587,16 +642,25 @@ class BIM_PT_boundary_conditions(Panel):
 
 
 class BIM_UL_boundary_conditions(UIList):
-    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
+    def draw_item(
+        self,
+        context,
+        layout: bpy.types.UILayout,
+        data: BIMStructuralProperties,
+        item: BoundaryCondition,
+        icon,
+        active_data,
+        active_propname,
+    ):
         if item:
             row = layout.row(align=True)
             row.label(text=f"{item.name} ({item.number_of_inverse_references})")
             row.label(text=BoundaryConditionsData.data["condition_classes"][item.ifc_definition_id])
 
-            if context.scene.BIMStructuralProperties.active_boundary_condition_id == item.ifc_definition_id:
+            if data.active_boundary_condition_id == item.ifc_definition_id:
                 row.operator("bim.edit_boundary_condition", text="", icon="CHECKMARK")
                 row.operator("bim.disable_editing_boundary_condition", text="", icon="CANCEL")
-            elif context.scene.BIMStructuralProperties.active_boundary_condition_id:
+            elif data.active_boundary_condition_id:
                 op = row.operator("bim.remove_boundary_condition", text="", icon="X")
                 op.boundary_condition = item.ifc_definition_id
             else:

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

@@ -54,7 +54,7 @@ class StructuralToolUI:
     @classmethod
     def draw(cls, context, layout):
         cls.layout = layout
-        # cls.props = context.scene.BIMStructuralProperties
+        cls.props = tool.Structural.get_structural_props()
 
         row = cls.layout.row(align=True)
         if not tool.Ifc.get():
@@ -99,12 +99,12 @@ class Hotkey(bpy.types.Operator, tool.Ifc.Operator):
         return operator.description or ""
 
     def _execute(self, context):
-        # self.props = context.scene.BIMStructuralProperties
+        # self.props = tool.Structural.get_structural_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.BIMStructuralProperties
+        # self.props = tool.Structural.get_structural_props()
         return self.execute(context)
 
     def draw(self, context):

src/bonsai/bonsai/tool/qto.py

@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import annotations
 import bpy
 import bonsai.core.tool
 import bonsai.bim.schema
@@ -24,12 +25,19 @@ import ifcopenshell
 import ifcopenshell.util.unit
 import ifcopenshell.util.element
 from mathutils import Vector
-from typing import Optional, Union, Literal
+from typing import Optional, Union, Literal, TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from bonsai.bim.module.qto.prop import BIMQtoProperties
 
 QuantityTypes = Literal["Q_LENGTH", "Q_AREA", "Q_VOLUME"]
 
 
 class Qto(bonsai.core.tool.Qto):
+    @classmethod
+    def get_qto_props(cls) -> BIMQtoProperties:
+        return bpy.context.scene.BIMQtoProperties
+
     @classmethod
     def get_radius_of_selected_vertices(cls, obj: bpy.types.Object) -> float:
         selected_verts = [v.co for v in obj.data.vertices if v.select]
@@ -41,7 +49,8 @@ class Qto(bonsai.core.tool.Qto):
 
     @classmethod
     def set_qto_result(cls, result: float) -> None:
-        bpy.context.scene.BIMQtoProperties.qto_result = str(round(result, 3))
+        props = cls.get_qto_props()
+        props.qto_result = str(round(result, 3))
 
     @classmethod
     def get_rounded_value(cls, new_quantity: float) -> float:

src/bonsai/bonsai/tool/structural.py

@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import annotations
 import bpy
 import ifcopenshell
 import ifcopenshell.util.representation
@@ -23,30 +24,46 @@ import json
 import bonsai.bim.helper
 import bonsai.core.tool
 import bonsai.tool as tool
-from typing import Union, Any
+from typing import Union, Any, TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from bonsai.bim.module.structural.prop import BIMStructuralProperties, BIMObjectStructuralProperties
 
 
 class Structural(bonsai.core.tool.Structural):
+    @classmethod
+    def get_structural_props(cls) -> BIMStructuralProperties:
+        return bpy.context.scene.BIMStructuralProperties
+
+    @classmethod
+    def get_object_structural_props(cls, obj: bpy.types.Object) -> BIMObjectStructuralProperties:
+        return obj.BIMStructuralProperties
+
     @classmethod
     def disable_editing_structural_analysis_model(cls) -> None:
-        bpy.context.scene.BIMStructuralProperties.active_structural_analysis_model_id = 0
+        props = cls.get_structural_props()
+        props.active_structural_analysis_model_id = 0
 
     @classmethod
     def disable_structural_analysis_model_editing_ui(cls) -> None:
-        bpy.context.scene.BIMStructuralProperties.is_editing = False
+        props = cls.get_structural_props()
+        props.is_editing = False
 
     @classmethod
     def enable_editing_structural_analysis_model(cls, model: Union[int, None]) -> None:
         if model:
-            bpy.context.scene.BIMStructuralProperties.active_structural_analysis_model_id = model
+            props = cls.get_structural_props()
+            props.active_structural_analysis_model_id = model
 
     @classmethod
     def enable_structural_analysis_model_editing_ui(cls) -> None:
-        bpy.context.scene.BIMStructuralProperties.is_editing = True
+        props = cls.get_structural_props()
+        props.is_editing = True
 
     @classmethod
     def enabled_structural_analysis_model_editing_ui(cls) -> bool:
-        return bpy.context.scene.BIMStructuralProperties.is_editing
+        props = cls.get_structural_props()
+        return props.is_editing
 
     @classmethod
     def ensure_representation_contexts(cls) -> None:
@@ -71,7 +88,7 @@ class Structural(bonsai.core.tool.Structural):
 
     @classmethod
     def get_active_structural_analysis_model(cls) -> ifcopenshell.entity_instance:
-        props = bpy.context.scene.BIMStructuralProperties
+        props = cls.get_structural_props()
         model = tool.Ifc.get().by_id(props.active_structural_analysis_model_id)
         return model
 
@@ -120,13 +137,13 @@ class Structural(bonsai.core.tool.Structural):
 
     @classmethod
     def get_structural_analysis_model_attributes(cls) -> dict[str, Any]:
-        props = bpy.context.scene.BIMStructuralProperties
+        props = cls.get_structural_props()
         attributes = bonsai.bim.helper.export_attributes(props.structural_analysis_model_attributes)
         return attributes
 
     @classmethod
     def load_structural_analysis_model_attributes(cls, data: dict[str, Any]) -> None:
-        props = bpy.context.scene.BIMStructuralProperties
+        props = cls.get_structural_props()
         props.structural_analysis_model_attributes.clear()
         schema = tool.Ifc.schema()
         for attribute in schema.declaration_by_name("IfcStructuralAnalysisModel").all_attributes():
@@ -149,7 +166,7 @@ class Structural(bonsai.core.tool.Structural):
     @classmethod
     def load_structural_analysis_models(cls) -> None:
         models = tool.Structural.get_ifc_structural_analysis_models()
-        props = bpy.context.scene.BIMStructuralProperties
+        props = cls.get_structural_props()
         props.structural_analysis_models.clear()
         for ifc_definition_id, model in models.items():
             new = props.structural_analysis_models.add()

src/bonsai/test/tool/test_qto.py

@@ -42,7 +42,8 @@ class TestGetRadiusOfSelectedVertices(test.bim.bootstrap.NewFile):
 class TestSetQtoResult(test.bim.bootstrap.NewFile):
     def test_run(self):
         subject.set_qto_result(123.4567)
-        assert bpy.context.scene.BIMQtoProperties.qto_result == "123.457"
+        props = tool.Qto.get_qto_props()
+        assert props.qto_result == "123.457"
 
 
 class TestGetRoundedValue(test.bim.bootstrap.NewFile):