Fix #3996. Reassigning occurrences or types now also reassigns the correlating occurrence or type.

src/blenderbim/blenderbim/bim/module/root/operator.py

@@ -103,17 +103,33 @@ class ReassignClass(bpy.types.Operator):
         predefined_type = context.scene.BIMRootProperties.ifc_predefined_type
         if predefined_type == "USERDEFINED":
             predefined_type = context.scene.BIMRootProperties.ifc_userdefined_type
+        reassigned_elements = set()
         for obj in objects:
             product = ifcopenshell.api.run(
                 "root.reassign_class",
                 self.file,
-                product=self.file.by_id(obj.BIMObjectProperties.ifc_definition_id),
+                product=tool.Ifc.get_entity(obj),
                 ifc_class=context.scene.BIMRootProperties.ifc_class,
                 predefined_type=predefined_type,
             )
-            obj.name = "{}/{}".format(product.is_a(), getattr(product, "Name", "None"))
-            tool.Ifc.link(product, obj)
+            reassigned_elements.add(product)
+            obj.name = tool.Loader.get_name(product)
             obj.BIMObjectProperties.is_reassigning_class = False
+
+        dependent_elements = set()
+        for reassigned_element in reassigned_elements:
+            if reassigned_element.is_a("IfcTypeObject"):
+                dependent_elements.update(ifcopenshell.util.element.get_types(product))
+            else:
+                element_type = ifcopenshell.util.element.get_type(product)
+                if element_type:
+                    dependent_elements.add(element_type)
+                    dependent_elements.update(ifcopenshell.util.element.get_types(element_type))
+
+        for dependent_element in dependent_elements:
+            obj = tool.Ifc.get_object(dependent_element)
+            if obj:
+                obj.name = tool.Loader.get_name(dependent_element)
         return {"FINISHED"}
 
 

src/blenderbim/blenderbim/tool/loader.py

@@ -61,7 +61,7 @@ class Loader(blenderbim.core.tool.Loader):
 
     @classmethod
     def get_name(cls, element):
-        return "{}/{}".format(element.is_a(), element.Name)
+        return "{}/{}".format(element.is_a(), getattr(element, "Name", "None"))
 
     @classmethod
     def link_mesh(cls, shape, mesh):

src/ifcopenshell-python/ifcopenshell/api/root/reassign_class.py

@@ -39,6 +39,14 @@ class Usecase:
         This is especially useful when dealing with poorly classified data from
         proprietary software with limited IFC capabilities.
 
+        If you are reassigning a type, the occurrence classes are also
+        reassigned to maintain validity.
+
+        Vice versa, if you are reassigning an occurrence, the type is also
+        reassigned in IFC4 and up. In IFC2X3, this may not occur if the type
+        cannot be unambiguously derived, so you are required to manually check
+        this.
+
         :param product: The IfcProduct that you want to change the class of.
         :type product: ifcopenshell.entity_instance.entity_instance
         :param ifc_class: The new IFC class you want to change it to.
@@ -70,10 +78,27 @@ class Usecase:
         }
 
     def execute(self):
-        element = ifcopenshell.util.schema.reassign_class(
-            self.file, self.settings["product"], self.settings["ifc_class"]
-        )
-        is_type = element.is_a("IfcTypeProduct")
+        element = self.reassign_class(self.settings["product"], self.settings["ifc_class"])
+
+        if element.is_a("IfcTypeProduct"):
+            for occurrence in ifcopenshell.util.element.get_types(element) or []:
+                ifc_class = ifcopenshell.util.type.get_applicable_entities(self.settings["ifc_class"])[0]
+                self.reassign_class(occurrence, ifc_class)
+        else:
+            element_type = ifcopenshell.util.element.get_type(element)
+            if element_type:
+                ifc_class = ifcopenshell.util.type.get_applicable_types(self.settings["ifc_class"])
+                if ifc_class and len(ifc_class) == 1:
+                    element_type = self.reassign_class(element_type, ifc_class[0])
+                ifc_class = element.is_a()
+                for occurrence in ifcopenshell.util.element.get_types(element_type) or []:
+                    if occurrence == element:
+                        continue
+                    self.reassign_class(occurrence, ifc_class)
+        return element
+
+    def reassign_class(self, element, ifc_class):
+        element = ifcopenshell.util.schema.reassign_class(self.file, element, ifc_class)
         if self.settings["predefined_type"] and hasattr(element, "PredefinedType"):
             try:
                 element.PredefinedType = self.settings["predefined_type"]
@@ -81,20 +106,9 @@ class Usecase:
                 # PredefinedType wasn't in the respective enum, assume it's actually USERDEFINED
                 # and set .ElementType / .ObjectType to the provided predefined type
                 element.PredefinedType = "USERDEFINED"
-                if is_type:
+                if element.is_a("IfcTypeProduct"):
                     element.ElementType = self.settings["predefined_type"]
                 else:
                     element.ObjectType = self.settings["predefined_type"]
 
-        # reassign classes for occurences connected to the type
-        if is_type:
-            for occurrence in ifcopenshell.util.element.get_types(element) or []:
-                ifc_class = ifcopenshell.util.type.get_applicable_entities(self.settings["ifc_class"])[0]
-                ifcopenshell.api.run(
-                    "root.reassign_class",
-                    self.file,
-                    product=occurrence,
-                    ifc_class=ifc_class,
-                    predefined_type=self.settings["predefined_type"],
-                )
         return element