Fix #2910. Bug where style colours were not synced prior to duplication.

src/blenderbim/blenderbim/bim/export_ifc.py

@@ -126,7 +126,7 @@ class IfcExporter:
                 continue
             try:
                 if isinstance(obj, bpy.types.Material):
-                    if self.has_changed_shading(obj):
+                    if tool.Ifc.has_changed_shading(obj):
                         blenderbim.core.style.update_style_colours(tool.Ifc, tool.Style, obj=obj)
                 else:
                     element = tool.Ifc.get_entity(obj)
@@ -149,10 +149,6 @@ class IfcExporter:
         checksum = obj.data.BIMMeshProperties.material_checksum
         return checksum != str([s.id() for s in tool.Geometry.get_styles(obj) if s])
 
-    def has_changed_shading(self, obj):
-        checksum = obj.BIMMaterialProperties.shading_checksum
-        return checksum != repr(np.array(obj.diffuse_color).tobytes())
-
     def sync_object_placement(self, obj):
         element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
         if not tool.Ifc.is_moved(obj):

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

@@ -24,6 +24,7 @@ import ifcopenshell.util.attribute
 import ifcopenshell.util.representation
 import blenderbim.bim.helper
 import blenderbim.tool as tool
+import blenderbim.core.style
 import blenderbim.core.material as core
 import blenderbim.bim.module.model.profile as model_profile
 from blenderbim.bim.module.material.prop import purge as material_prop_purge
@@ -666,8 +667,12 @@ class CopyMaterial(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         blender_material = context.active_object.active_material
         material = tool.Ifc.get_entity(blender_material)
+
+        if tool.Ifc.has_changed_shading(blender_material):
+            blenderbim.core.style.update_style_colours(tool.Ifc, tool.Style, obj=blender_material)
+
         copied_material = ifcopenshell.api.run("material.copy_material", tool.Ifc.get(), material=material)
-        copied_blender_material = bpy.data.materials.new(blender_material.name)
+        copied_blender_material = blender_material.copy()
         copied_style = self.get_style(copied_material)
         tool.Ifc.link(copied_material, copied_blender_material)
         if copied_style:

src/blenderbim/blenderbim/tool/ifc.py

@@ -46,6 +46,11 @@ class Ifc(blenderbim.core.tool.Ifc):
         if IfcStore.get_file():
             return IfcStore.get_file().schema
 
+    @classmethod
+    def has_changed_shading(cls, obj):
+        checksum = obj.BIMMaterialProperties.shading_checksum
+        return checksum != repr(np.array(obj.diffuse_color).tobytes())
+
     @classmethod
     def is_deleted(cls, element):
         return element.id() in IfcStore.deleted_ids