bim.merge_identical_objects for merging identical styles

Button location - https://i.imgur.com/3O8gHUn.png

Could also be used as a temporary workaround for #5446

src/bonsai/bonsai/bim/module/debug/__init__.py

@@ -27,6 +27,7 @@ classes = (
     operator.DebugActiveDrawing,
     operator.InspectFromObject,
     operator.InspectFromStepId,
+    operator.MergeIdenticalObjects,
     operator.OverrideDisplayType,
     operator.ParseExpress,
     operator.PipInstall,

src/bonsai/bonsai/bim/module/debug/operator.py

@@ -688,6 +688,52 @@ class PurgeUnusedObjects(bpy.types.Operator, tool.Ifc.Operator):
                 bpy.ops.bim.load_materials()
 
 
+class MergeIdenticalObjects(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.merge_identical_objects"
+    bl_label = "Merge Identical Objects"
+    bl_options = {"REGISTER", "UNDO"}
+
+    object_type: bpy.props.EnumProperty(
+        name="Object Type",
+        items=(
+            ("TYPE", "Type", ""),
+            ("PROFILE", "Profile", ""),
+            ("STYLE", "Style", ""),
+            ("MATERIAL", "Material", ""),
+        ),
+    )
+
+    def _execute(self, context):
+        object_type = self.object_type
+        if object_type == "STYLE":
+            merged_data = tool.Debug.merge_identical_objects("style")
+            if merged_data:
+                print("Merged styles:")
+                for style_type, style_names in merged_data.items():
+                    print(f"- {style_type}: {', '.join(style_names)}")
+            merged = sum(len(v) for v in merged_data.values())
+        else:
+            self.report({"ERROR"}, f"Invalid object type {object_type}.")
+            return {"CANCELLED"}
+
+        msg = " See system console for details." if merged else ""
+        self.report({"INFO"}, f"{merged} identical {object_type.lower()}s were merged.{msg}")
+
+        if merged == 0:
+            return
+
+        scene = context.scene
+        if object_type == "PROFILE":
+            if scene.BIMProfileProperties.is_editing:
+                bpy.ops.bim.load_profiles()
+        elif object_type == "STYLE":
+            if scene.BIMStylesProperties.is_editing:
+                bpy.ops.bim.load_styles()
+        elif object_type == "MATERIAL":
+            if scene.BIMMaterialProperties.is_editing:
+                bpy.ops.bim.load_materials()
+
+
 class PipInstall(bpy.types.Operator):
     bl_idname = "bim.pip_install"
     bl_label = "Pip Install"

src/bonsai/bonsai/bim/module/project/ui.py

@@ -525,4 +525,7 @@ class BIM_PT_purge(Panel):
         layout.operator("bim.purge_unused_objects", text="Purge Unused Profiles").object_type = "PROFILE"
         layout.operator("bim.purge_unused_objects", text="Purge Unused Types").object_type = "TYPE"
         layout.operator("bim.purge_unused_objects", text="Purge Unused Materials").object_type = "MATERIAL"
-        layout.operator("bim.purge_unused_objects", text="Purge Unused Styles").object_type = "STYLE"
+        row = layout.row(align=True)
+        row.label(text="Styles: ")
+        row.operator("bim.purge_unused_objects", text="Purge Unused").object_type = "STYLE"
+        row.operator("bim.merge_identical_objects", text="Merge Identical").object_type = "STYLE"

src/bonsai/bonsai/tool/debug.py

@@ -17,16 +17,20 @@
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
+import json
 import bpy
 import ifcopenshell.express
 import ifcopenshell.express.schema
 import ifcopenshell.express.schema_class
 import ifcopenshell.util.element
+import ifcopenshell.util.schema
+import bonsai.core.style
 import bonsai.core.tool
 import bonsai.tool as tool
 from bonsai.bim.ifc import IfcStore
 from mathutils import Vector
-from typing import Iterable
+from collections import defaultdict
+from typing import Iterable, Literal
 
 
 class Debug(bonsai.core.tool.Debug):
@@ -98,3 +102,54 @@ class Debug(bonsai.core.tool.Debug):
                 print(f"{class_string: <50} {unused[ifc_class]: >5}")
 
         return sum(unused.values())
+
+    @classmethod
+    def merge_identical_objects(cls, object_type: Literal["style"]) -> dict[str, list[str]]:
+        """Merge identical objects.
+
+        Note that Styles UI (or other UI) should be updated manually after using this method.
+        """
+
+        def get_hash(element: ifcopenshell.entity_instance) -> int:
+            return hash(json.dumps(element.get_info_2(include_identifier=False, recursive=True), sort_keys=True))
+
+        ifc_file = tool.Ifc.get()
+
+        if object_type == "style":
+            declaration = tool.Ifc.schema().declaration_by_name("IfcPresentationStyle")
+            merged_element_types: dict[str, list[str]] = {}
+            element_types = [e.name() for e in ifcopenshell.util.schema.get_subtypes(declaration)]
+        for element_type in element_types:
+            elements = ifc_file.by_type(element_type)
+
+            # Calculate hashes.
+            hash_to_elements: defaultdict[int, list[ifcopenshell.entity_instance]] = defaultdict(list)
+            for element in elements:
+                # Ignore unnamed styles as they may be not safe to merge.
+                if not element.Name:
+                    continue
+                element_hash = get_hash(element)
+                hash_to_elements[element_hash].append(element)
+
+            merged_elements_names: list[str] = []
+            # Merge styles.
+            for elements in hash_to_elements.values():
+                if len(elements) == 1:
+                    continue
+
+                main_element = elements[0]
+                if object_type == "style":
+                    main_style_obj = tool.Ifc.get_object(main_element)
+                    for style in elements[1:]:
+                        ifcopenshell.util.element.replace_element(style, main_element)
+                        style_obj = tool.Ifc.get_object(style)
+                        # Only for surface styles.
+                        if style_obj:
+                            assert main_style_obj
+                            style_obj.user_remap(main_style_obj)
+                        merged_elements_names.append(style.Name)
+                        bonsai.core.style.remove_style(tool.Ifc, tool.Style, style, reload_styles_ui=False)
+
+            if merged_elements_names:
+                merged_element_types[element_type] = merged_elements_names
+        return merged_element_types

src/bonsai/test/tool/test_debug.py

@@ -19,6 +19,7 @@
 import os
 import bpy
 import ifcopenshell
+import ifcopenshell.util.schema
 import bonsai.core.tool
 import bonsai.tool as tool
 from test.bim.bootstrap import NewFile
@@ -66,3 +67,23 @@ class TestPurgeHdf5Cache(NewFile):
         # On Unix loaded files are not locked.
         paths = [loaded_file_path] if os.name == "nt" else []
         assert [f for f in cache_dir.iterdir() if f.suffix == ".h5"] == paths
+
+
+class TestMergeIdenticalObject(NewFile):
+    def test_merge_identical_styles(self):
+        tool.Ifc.set(ifc := ifcopenshell.file())
+        declaration = tool.Ifc.schema().declaration_by_name("IfcPresentationStyle")
+        style_types = [d.name() for d in ifcopenshell.util.schema.get_subtypes(declaration)]
+        for style_type in style_types:
+            ifc.create_entity(style_type, Name=style_type)
+            ifc.create_entity(style_type, Name=style_type)
+            ifc.create_entity(style_type, Name="NotToMerge")
+            if style_type == "IfcSurfaceStyle":
+                for style in ifc.by_type(style_type):
+                    style.Styles = (ifc.create_entity("IfcSurfaceStyleShading"),)
+            elif style_type == "IfcFillAreaStyle":
+                for style in ifc.by_type(style_type):
+                    style.FillStyles = (ifc.create_entity("IfcFillAreaStyleHatching"),)
+
+        merge_data = subject.merge_identical_objects("style")
+        assert merge_data == {style_type: [style_type] for style_type in style_types}