First Commit

2026-05-31 10:17:09 +07:00
commit 17a9c69379
4547 changed files with 1170384 additions and 0 deletions
@@ -0,0 +1,135 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2021 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/>.
+
+
+import ifcopenshell
+import ifcopenshell.api.owner
+import ifcopenshell.util.element
+
+
+def unassign_material(file: ifcopenshell.file, products: list[ifcopenshell.entity_instance]) -> None:
+    """Removes any material relationship with the list of products
+
+    A product can only have one material assigned to it, which is why it is
+    not necessary to specify the material to unassign. The material is not
+    removed, only the relationship is removed.
+
+    If the product does not have a material, nothing happens.
+
+    Unassigning a LayerSet or ProfileSet from the product type will also
+    remove all Usages of the set.
+
+    :param products: The list IfcProducts that may or may not have a material
+    :return: None
+
+    Example:
+
+    .. code:: python
+
+        concrete = ifcopenshell.api.material.add_material(model, name="CON01", category="concrete")
+
+        # Let's imagine a concrete bench made out of concrete.
+        bench_type = ifcopenshell.api.root.create_entity(model, ifc_class="IfcFurnitureType")
+        ifcopenshell.api.material.assign_material(model,
+            products=[bench_type], type="IfcMaterial", material=concrete)
+
+        # Let's change our mind and remove the concrete assignment. The
+        # concrete material still exists, but the bench is no longer made
+        # out of concrete now.
+        ifcopenshell.api.material.unassign_material(model, products=[bench_type])
+    """
+    usecase = Usecase()
+    usecase.file = file
+    return usecase.execute(products)
+
+
+class Usecase:
+    file: ifcopenshell.file
+
+    def execute(self, products: list[ifcopenshell.entity_instance]) -> None:
+        if not products:
+            return
+        self.products = set(products)
+
+        self.remove_material_usages_from_types()
+        self.unassign_materials()
+
+    def remove_material_usages_from_types(self) -> None:
+        # remove material usages from types
+        for product in self.products:
+            if not product.is_a("IfcTypeObject"):
+                continue
+            material = ifcopenshell.util.element.get_material(product)
+            if not material:
+                continue
+            if material.is_a() in ["IfcMaterialLayerSet", "IfcMaterialProfileSet"]:
+                # Remove set usages
+                # TODO: be more considerate and remove only usages
+                # associated with the set + product type, not all usages?
+                for inverse in self.file.get_inverse(material):
+                    if self.file.schema == "IFC2X3":
+                        if not inverse.is_a("IfcMaterialLayerSetUsage"):
+                            continue
+                        # in IFC2X3 there is no .AssociatedTo
+                        for inverse2 in self.file.get_inverse(inverse):
+                            if inverse2.is_a("IfcRelAssociatesMaterial"):
+                                history = inverse2.OwnerHistory
+                                self.file.remove(inverse2)
+                                if history:
+                                    ifcopenshell.util.element.remove_deep2(self.file, history)
+                    else:
+                        if not inverse.is_a("IfcMaterialUsageDefinition"):
+                            continue
+                        for rel in inverse.AssociatedTo:
+                            history = rel.OwnerHistory
+                            self.file.remove(rel)
+                            if history:
+                                ifcopenshell.util.element.remove_deep2(self.file, history)
+                    self.file.remove(inverse)
+
+    def unassign_materials(self) -> None:
+        associations: set[ifcopenshell.entity_instance] = set()
+        for product in self.products:
+            associations.update(product.HasAssociations)
+
+        # we ensure that `associations` won't have removed elements
+        # to avoid crash during `material_inverses.issubset(associations)`
+        while associations:
+            rel = next(iter(associations))
+
+            if not rel.is_a("IfcRelAssociatesMaterial"):
+                associations.remove(rel)
+            else:
+                material = rel.RelatingMaterial
+                related_objects = set(rel.RelatedObjects) - self.products
+
+                if material.is_a() in ["IfcMaterialLayerSetUsage", "IfcMaterialProfileSetUsage"]:
+                    # Warning: this may leave the model in a non-compliant state.
+                    material_inverses = set(self.file.get_inverse(material))
+                    if material_inverses.issubset(associations) and not related_objects:
+                        self.file.remove(material)
+                associations.remove(rel)
+
+                if not related_objects:
+                    history = rel.OwnerHistory
+                    self.file.remove(rel)
+                    if history:
+                        ifcopenshell.util.element.remove_deep2(self.file, history)
+                    continue
+                rel.RelatedObjects = list(related_objects)
+                ifcopenshell.api.owner.update_owner_history(self.file, element=rel)