You can now duplicate or linked duplicate objects in IFC. Neat. See #1222.

src/ifcblenderexport/blenderbim/bim/module/geometry/map_representation.py

@@ -10,12 +10,13 @@ class Usecase:
             self.settings[key] = value
 
     def execute(self):
-        self.get_mapping_source()
-
         self.zero = self.file.createIfcCartesianPoint((0.0, 0.0, 0.0))
         self.x_axis = self.file.createIfcDirection((1.0, 0.0, 0.0))
         self.y_axis = self.file.createIfcDirection((0.0, 1.0, 0.0))
         self.z_axis = self.file.createIfcDirection((0.0, 0.0, 1.0))
+
+        self.get_mapping_source()
+
         mapping_target = self.file.createIfcCartesianTransformationOperator3D(
             self.x_axis, self.y_axis, self.zero, 1, self.z_axis
         )

src/ifcblenderexport/blenderbim/bim/module/geometry/operator.py

@@ -179,20 +179,23 @@ class MapRepresentation(bpy.types.Operator):
     bl_idname = "bim.map_representation"
     bl_label = "Map Representation"
     obj: bpy.props.StringProperty()
-    target_obj: bpy.props.StringProperty()
+    obj_data: bpy.props.StringProperty()
 
     def execute(self, context):
         objs = [bpy.data.objects.get(self.obj)] if self.obj else bpy.context.selected_objects
-        target_obj = bpy.data.objects.get(self.obj) if self.obj else bpy.context.active_object
+        obj_data = bpy.data.meshes.get(self.obj_data) if self.obj_data else bpy.context.active_object.data
-        objs = [o for o in objs if o != target_obj]
+        objs = [o for o in objs if o.data != obj_data]
         self.file = IfcStore.get_file()
 
         for obj in objs:
             bpy.ops.bim.edit_object_placement(obj=obj.name)
             product = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
-            old_representation = self.file.by_id(obj.data.BIMMeshProperties.ifc_definition_id)
+            if obj.data.BIMMeshProperties.ifc_definition_id:
-            target_representation = self.file.by_id(target_obj.data.BIMMeshProperties.ifc_definition_id)
+                old_representation = self.file.by_id(obj.data.BIMMeshProperties.ifc_definition_id)
-            obj.data = target_obj.data
+            else:
+                old_representation = None
+            target_representation = self.file.by_id(obj_data.BIMMeshProperties.ifc_definition_id)
+            obj.data = obj_data
             result = map_representation.Usecase(
                 self.file,
                 {
@@ -201,7 +204,8 @@ class MapRepresentation(bpy.types.Operator):
                 },
             ).execute()
             assign_representation.Usecase(self.file, {"product": product, "representation": result}).execute()
-            bpy.ops.bim.remove_representation(ifc_definition_id=old_representation.id())
+            if old_representation:
+                bpy.ops.bim.remove_representation(ifc_definition_id=old_representation.id())
             Data.load(obj.BIMObjectProperties.ifc_definition_id)
         return {"FINISHED"}
 

src/ifcblenderexport/blenderbim/bim/module/root/__init__.py

@@ -8,6 +8,7 @@ classes = (
     operator.AssignClass,
     operator.UnassignClass,
     operator.UnlinkObject,
+    operator.CopyClass,
     prop.BIMRootProperties,
     ui.BIM_PT_class,
 )

src/ifcblenderexport/blenderbim/bim/module/root/copy_class.py

@@ -0,0 +1,37 @@
+import ifcopenshell
+
+
+class Usecase:
+    def __init__(self, file, settings=None):
+        self.file = file
+        self.settings = {"product": None}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        result = self.file.create_entity(self.settings["product"].is_a())
+        self.schema = ifcopenshell.ifcopenshell_wrapper.schema_by_name(self.file.schema)
+        self.copy_attributes(self.settings["product"], result)
+        for inverse in self.file.get_inverse(self.settings["product"]):
+            for i, value in enumerate(inverse):
+                if value == self.settings["product"]:
+                    new_inverse = self.file.create_entity(inverse.is_a())
+                    self.copy_attributes(inverse, new_inverse)
+                    new_inverse[i] = result
+                elif isinstance(value, (tuple, list)) and self.settings["product"] in value:
+                    new_value = list(value)
+                    new_value.append(result)
+                    inverse[i] = new_value
+        if result.is_a("IfcProduct"):
+            result.Representation = None
+        elif result.is_a("IfcTypeProduct"):
+            result.RepresentationMaps = None
+        return result
+
+    def copy_attributes(self, from_element, to_element):
+        declaration = self.schema.declaration_by_name(from_element.is_a())
+        for attribute in declaration.all_attributes():
+            if attribute.name() == "GlobalId":
+                setattr(to_element, attribute.name(), ifcopenshell.guid.new())
+            else:
+                setattr(to_element, attribute.name(), getattr(from_element, attribute.name()))

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

@@ -5,6 +5,7 @@ import ifcopenshell.util.schema
 import blenderbim.bim.module.root.create_product as create_product
 import blenderbim.bim.module.root.remove_product as remove_product
 import blenderbim.bim.module.root.reassign_class as reassign_class
+import blenderbim.bim.module.root.copy_class as copy_class
 from blenderbim.bim.module.owner.api import create_owner_history
 from blenderbim.bim.ifc import IfcStore
 
@@ -203,3 +204,32 @@ class UnlinkObject(bpy.types.Operator):
             if obj.BIMObjectProperties.ifc_definition_id:
                 obj.BIMObjectProperties.ifc_definition_id = 0
         return {"FINISHED"}
+
+
+class CopyClass(bpy.types.Operator):
+    bl_idname = "bim.copy_class"
+    bl_label = "Copy Class"
+    obj: bpy.props.StringProperty()
+
+    def execute(self, context):
+        self.file = IfcStore.get_file()
+        if self.obj:
+            objects = [bpy.data.objects.get(self.obj)]
+        else:
+            objects = bpy.context.selected_objects
+        for obj in objects:
+            if not obj.BIMObjectProperties.ifc_definition_id:
+                continue
+            result = copy_class.Usecase(self.file, {
+                "product": self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+            }).execute()
+            obj.BIMObjectProperties.ifc_definition_id = result.id()
+            if obj.data.users == 1:
+                bpy.ops.bim.add_representation(obj=obj.name)
+            else:
+                obj_data = obj.data.name
+                temporary_mesh = bpy.data.meshes.new("Temporary Mesh")
+                obj.data = temporary_mesh
+                bpy.ops.bim.map_representation(obj=obj.name, obj_data=obj_data)
+                bpy.data.meshes.remove(temporary_mesh)
+        return {"FINISHED"}

src/ifcblenderexport/blenderbim/bim/module/root/ui.py

@@ -34,6 +34,7 @@ class BIM_PT_class(Panel):
                     name += "[{}]".format(data["PredefinedType"])
                 row = self.layout.row(align=True)
                 row.label(text=name)
+                row.operator("bim.copy_class", icon="DUPLICATE", text="").obj = context.active_object.name
                 row.operator("bim.unlink_object", icon="UNLINKED", text="").obj = context.active_object.name
                 row.operator("bim.enable_reassign_class", icon="GREASEPENCIL", text="")
                 row.operator("bim.unassign_class", icon="X", text="").obj = context.active_object.name