You can now apply drawing styles to elements with material set usages

Moult · Moult · commit e1fa6fb30636 · 2020-12-03T22:17:46.000+11:00
diff --git a/src/ifcblenderexport/blenderbim/bim/cut_ifc.py b/src/ifcblenderexport/blenderbim/bim/cut_ifc.py
@@ -771,13 +771,13 @@ def get_ifc_element(self, global_id):
 
     def get_classes(self, element, position):
         classes = [position, element.is_a()]
-        for association in element.HasAssociations:
-            if association.is_a("IfcRelAssociatesMaterial"):
-                classes.append(
-                    "material-{}".format(
-                        re.sub("[^0-9a-zA-Z]+", "", self.get_material_name(association.RelatingMaterial))
-                    )
+        material = ifcopenshell.util.element.get_material(element)
+        if material:
+            classes.append(
+                "material-{}".format(
+                    re.sub("[^0-9a-zA-Z]+", "", self.get_material_name(material))
                 )
+            )
         classes.append("globalid-{}".format(element.GlobalId))
         for attribute in self.attributes:
             result = self.selector.get_element_value(element, attribute)
diff --git a/src/ifcopenshell-python/ifcopenshell/util/element.py b/src/ifcopenshell-python/ifcopenshell/util/element.py
@@ -67,11 +67,19 @@ def get_material(element):
     if hasattr(element, "HasAssociations") and element.HasAssociations:
         for relationship in element.HasAssociations:
             if relationship.is_a("IfcRelAssociatesMaterial"):
+                if relationship.RelatingMaterial.is_a("IfcMaterialLayerSetUsage"):
+                    return relationship.RelatingMaterial.ForLayerSet
+                elif relationship.RelatingMaterial.is_a("IfcMaterialProfileSetUsage"):
+                    return relationship.RelatingMaterial.ForProfileSet
                 return relationship.RelatingMaterial
     relating_type = get_type(element)
     if hasattr(relating_type, "HasAssociations") and relating_type.HasAssociations:
         for relationship in relating_type.HasAssociations:
             if relationship.is_a("IfcRelAssociatesMaterial"):
+                if relationship.RelatingMaterial.is_a("IfcMaterialLayerSetUsage"):
+                    return relationship.RelatingMaterial.ForLayerSet
+                elif relationship.RelatingMaterial.is_a("IfcMaterialProfileSetUsage"):
+                    return relationship.RelatingMaterial.ForProfileSet
                 return relationship.RelatingMaterial
 
 
