#2094. Removing materials now removes material definitions too for styles

src/ifcopenshell-python/ifcopenshell/api/material/add_material_set.py

@@ -0,0 +1,32 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of IfcOpenShell.
+#
+# IfcOpenShell is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# IfcOpenShell is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
+
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {"name": "Unnamed", "set_type": "IfcMaterialConstituentSet"}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        if self.settings["set_type"] == "IfcMaterialLayerSet":
+            return self.file.create_entity("IfcMaterialLayerSet", LayerSetName=self.settings["name"] or "Unnamed")
+        elif self.settings["set_type"] == "IfcMaterialList":
+            return self.file.create_entity("IfcMaterialList")
+        return self.file.create_entity(self.settings["set_type"], Name=self.settings["name"] or "Unnamed")

src/ifcopenshell-python/ifcopenshell/api/material/assign_material.py

@@ -124,7 +124,7 @@ class Usecase:
         )
 
     def get_rel_associates_material(self, material):
-        if self.file.schema == "IFC2X3":
+        if self.file.schema == "IFC2X3" or material.is_a("IfcMaterialList"):
             rel = [
                 r
                 for r in self.file.by_type("IfcRelAssociatesMaterial")

src/ifcopenshell-python/ifcopenshell/api/material/remove_material.py

@@ -29,8 +29,8 @@ class Usecase:
     def execute(self):
         inverse_elements = self.file.get_inverse(self.settings["material"])
         self.file.remove(self.settings["material"])
-        # TODO: this is probably not robust enough
-        # TODO: purge material definition representation
+        # TODO: Right now, we we choose only to delete set items (e.g. a layer) but not the material set
+        # This can lead to invalid material sets, but we assume the user will deal with it
         for inverse in inverse_elements:
             if inverse.is_a("IfcMaterialConstituent"):
                 self.file.remove(inverse)
@@ -40,3 +40,9 @@ class Usecase:
                 self.file.remove(inverse)
             elif inverse.is_a("IfcRelAssociatesMaterial"):
                 self.file.remove(inverse)
+            elif inverse.is_a("IfcMaterialDefinitionRepresentation"):
+                for representation in inverse.Representations:
+                    for item in representation.Items:
+                        self.file.remove(item)
+                    self.file.remove(representation)
+                self.file.remove(inverse)