prioritize external styles on ifc import

also found a way to switch shade graph for two materials without juggling active materials and active objects - it was necessary to make it work on import without adding temporary active object

src/blenderbim/blenderbim/bim/import_ifc.py

@@ -1485,22 +1485,11 @@ def create_style(self, style, blender_material=None):
         blender_material.BIMMaterialProperties.ifc_style_id = style.id()
         self.material_creator.styles[style.id()] = blender_material
 
-        rendering_style = None
-        texture_style = None
-
-        for surface_style in style.Styles:
-            if surface_style.is_a() == "IfcSurfaceStyleShading":
-                tool.Loader.create_surface_style_shading(blender_material, surface_style)
-            elif surface_style.is_a("IfcSurfaceStyleRendering"):
-                rendering_style = surface_style
-                tool.Loader.create_surface_style_rendering(blender_material, surface_style)
-            elif surface_style.is_a("IfcSurfaceStyleWithTextures"):
-                texture_style = surface_style
-
-        if rendering_style and texture_style:
-            tool.Loader.create_surface_style_with_textures(blender_material, rendering_style, texture_style)
-
-        tool.Style.record_shading(blender_material)
+        style_elements = tool.Style.get_style_elements(blender_material)
+        if tool.Style.has_blender_external_style(style_elements):
+            blender_material.BIMStyleProperties.active_style_type = "External"
+        else:
+            blender_material.BIMStyleProperties.active_style_type = "Shading"
 
     def place_objects_in_collections(self):
         for ifc_definition_id, obj in self.added_data.items():

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

@@ -267,8 +267,13 @@ class ActivateExternalStyle(bpy.types.Operator, tool.Ifc.Operator):
     bl_label = "Activate External Style"
     bl_options = {"REGISTER", "UNDO", "INTERNAL"}
 
+    material_name: bpy.props.StringProperty(name="Material Name", default="")
+
     def _execute(self, context):
-        material = context.active_object.active_material
+        if not self.material_name:
+            material = context.active_object.active_material
+        else:
+            material = bpy.data.materials[self.material_name]
         external_style = tool.Style.get_style_elements(material)["IfcExternallyDefinedSurfaceStyle"]
         data_block_type, data_block = external_style.Identification.split("/")
         style_path = Path(tool.Ifc.resolve_uri(external_style.Location))
@@ -297,7 +302,7 @@ def _execute(self, context):
             setattr(material, prop_name, getattr(db["data_block"], prop_name))
 
         if material.use_nodes:
-            tool.Blender.copy_node_graph_to_active_object(context, db["data_block"])
+            tool.Blender.copy_node_graph(material, db["data_block"])
         bpy.data.materials.remove(db["data_block"])
 
 

src/blenderbim/blenderbim/bim/module/style/prop.py

@@ -61,7 +61,7 @@ def update_shading_styles(self, context):
             materials_to_objects[blender_material] = obj
 
     for mat, obj in materials_to_objects.items():
-        tool.Style.change_current_style_type(context, obj, mat, self.active_style_type)
+        tool.Style.change_current_style_type(mat, self.active_style_type)
 
 
 class BIMStylesProperties(PropertyGroup):
@@ -79,11 +79,11 @@ class BIMStylesProperties(PropertyGroup):
 
 
 def update_shading_style(self, context):
-    blender_material = context.active_object.active_material
+    blender_material = self.id_data
     style_elements = tool.Style.get_style_elements(blender_material)
     if self.active_style_type == "External":
-        if "IfcExternallyDefinedSurfaceStyle" in style_elements:
-            bpy.ops.bim.activate_external_style()
+        if tool.Style.has_blender_external_style(style_elements):
+            bpy.ops.bim.activate_external_style(material_name=blender_material.name)
 
     elif self.active_style_type == "Shading":
         style_elements = tool.Style.get_style_elements(blender_material)
@@ -101,6 +101,7 @@ def update_shading_style(self, context):
 
         if rendering_style and texture_style:
             tool.Loader.create_surface_style_with_textures(blender_material, rendering_style, texture_style)
+    tool.Style.record_shading(blender_material)
 
 
 class BIMStyleProperties(PropertyGroup):

src/blenderbim/blenderbim/tool/blender.py

@@ -118,32 +118,31 @@ def get_shader_editor_context(cls):
                             return context_override
 
     @classmethod
-    def copy_node_graph_to_active_object(cls, context, material):
-        """make sure to override `context.active_object`
-        to you want change node graph for the object that's not actually active
-        """
+    def copy_node_graph(cls, material_to, material_from):
         temp_override = cls.get_shader_editor_context()
-        old_material = context.active_object.active_material
-        new_material = material
+        shader_editor = temp_override["space"]
 
         # remove all nodes from the current material
-        for n in old_material.node_tree.nodes[:]:
-            old_material.node_tree.nodes.remove(n)
+        for n in material_to.node_tree.nodes[:]:
+            material_to.node_tree.nodes.remove(n)
 
-        # change current material and make other window's shader editor is updated
-        context.active_object.active_material = new_material
-        temp_override["space"].node_tree = new_material.node_tree
+        previous_pin_setting = shader_editor.pin
+        # required to be able to change material to something else
+        shader_editor.pin = True
+        shader_editor.node_tree = material_from.node_tree
 
         # select all nodes and copy them to clipboard
-        for node in new_material.node_tree.nodes:
+        for node in material_from.node_tree.nodes:
             node.select = True
         bpy.ops.node.clipboard_copy(temp_override)
 
         # back to original material
-        context.active_object.active_material = old_material
-        temp_override["space"].node_tree = old_material.node_tree
+        shader_editor.node_tree = material_to.node_tree
         bpy.ops.node.clipboard_paste(temp_override, offset=(0, 0))
 
+        # restore shader editor settings
+        shader_editor.pin = previous_pin_setting
+
     @classmethod
     def update_screen(cls):
         bpy.ops.wm.redraw_timer(type="DRAW_WIN_SWAP", iterations=1)

src/blenderbim/blenderbim/tool/style.py

@@ -227,6 +227,11 @@ def import_external_style_attributes(cls, style, obj):
         attributes.clear()
         blenderbim.bim.helper.import_attributes2(style, attributes)
 
+    @classmethod
+    def has_blender_external_style(cls, style_elements):
+        external_style = style_elements.get("IfcExternallyDefinedSurfaceStyle", None)
+        return bool(external_style and external_style.Location.endswith(".blend"))
+
     @classmethod
     def is_editing_styles(cls):
         return bpy.context.scene.BIMStylesProperties.is_editing
@@ -243,6 +248,5 @@ def select_elements(cls, elements):
                 obj.select_set(True)
 
     @classmethod
-    def change_current_style_type(cls, context, obj, blender_material, style_type):
-        with context.temp_override(active_object=obj):
-            blender_material.BIMStyleProperties.active_style_type = style_type
+    def change_current_style_type(cls, blender_material, style_type):
+        blender_material.BIMStyleProperties.active_style_type = style_type