Styles are applied per mesh data now (potentially dangerous). Fix crash when switching to representation which has styles from an unstyled mesh.

src/blenderbim/blenderbim/bim/import_ifc.py

@@ -60,7 +60,6 @@ class MaterialCreator:
 
     def create(self, element, obj, mesh):
         self.mesh = mesh
-        self.obj = obj
         if (hasattr(element, "Representation") and not element.Representation) or (
             hasattr(element, "RepresentationMaps") and not element.RepresentationMaps
         ):
@@ -140,11 +139,11 @@ class MaterialCreator:
     def assign_material_slots_to_faces(self):
         if "ios_materials" not in self.mesh or not self.mesh["ios_materials"]:
             return
-        if len(self.obj.material_slots) == 1:
+        if len(self.mesh.materials) == 1:
             return
         material_to_slot = {}
         for i, material in enumerate(self.mesh["ios_materials"]):
-            slot_index = self.obj.material_slots.find(self.styles[material].name)
+            slot_index = self.mesh.materials.find(self.styles[material].name)
             material_to_slot[i] = slot_index
 
         if len(self.mesh.polygons) == len(self.mesh["ios_material_ids"]):

src/blenderbim/blenderbim/bim/module/model/slab.py

@@ -681,32 +681,33 @@ class EditExtrusionProfile(bpy.types.Operator, tool.Ifc.Operator):
 
         # Only certain classes should have a footprint
         if element.is_a() not in ("IfcSlab", "IfcRamp"):
-            return {"FINISHED"}
+            return
 
         footprint_context = ifcopenshell.util.representation.get_context(
             tool.Ifc.get(), "Plan", "FootPrint", "SKETCH_VIEW"
         )
-        if footprint_context:
-            curves = [profile.OuterCurve]
-            if profile.is_a("IfcArbitraryProfileDefWithVoids"):
-                curves.extend(profile.InnerCurves)
-            new_footprint = ifcopenshell.api.run(
-                "geometry.add_footprint_representation", tool.Ifc.get(), context=footprint_context, curves=curves
+        if not footprint_context:
+            return
+
+        curves = [profile.OuterCurve]
+        if profile.is_a("IfcArbitraryProfileDefWithVoids"):
+            curves.extend(profile.InnerCurves)
+        new_footprint = ifcopenshell.api.run(
+            "geometry.add_footprint_representation", tool.Ifc.get(), context=footprint_context, curves=curves
+        )
+        old_footprint = ifcopenshell.util.representation.get_representation(
+            element, "Plan", "FootPrint", "SKETCH_VIEW"
+        )
+        if old_footprint:
+            for inverse in tool.Ifc.get().get_inverse(old_footprint):
+                ifcopenshell.util.element.replace_attribute(inverse, old_footprint, new_footprint)
+            blenderbim.core.geometry.remove_representation(
+                tool.Ifc, tool.Geometry, obj=obj, representation=old_footprint
             )
-            old_footprint = ifcopenshell.util.representation.get_representation(
-                element, "Plan", "FootPrint", "SKETCH_VIEW"
+        else:
+            ifcopenshell.api.run(
+                "geometry.assign_representation", tool.Ifc.get(), product=element, representation=new_footprint
             )
-            if old_footprint:
-                for inverse in tool.Ifc.get().get_inverse(old_footprint):
-                    ifcopenshell.util.element.replace_attribute(inverse, old_footprint, new_footprint)
-                blenderbim.core.geometry.remove_representation(
-                    tool.Ifc, tool.Geometry, obj=obj, representation=old_footprint
-                )
-            else:
-                ifcopenshell.api.run(
-                    "geometry.assign_representation", tool.Ifc.get(), product=element, representation=new_footprint
-                )
-        return {"FINISHED"}
 
 
 class ResetVertex(bpy.types.Operator):