WARNING: Remove collection syncing. The outliner no longer is used to change spatial hierarchy.

This is a BREAKING change (on purpose). If you want to change containment / aggregation, use the UI panels, not drag and drop on the outliner.

src/blenderbim/blenderbim/bim/export_ifc.py

@@ -99,7 +99,6 @@ class IfcExporter:
                     continue
                 if obj.library:
                     continue
-                tool.Collector.sync(obj, skip_unlinking)
                 result = self.sync_object_placement(obj)
                 if result:
                     results.append(result)

src/blenderbim/blenderbim/bim/import_ifc.py

@@ -302,7 +302,9 @@ class IfcImporter:
             self.setup_viewport_camera()
         self.setup_arrays()
         self.profile_code("Setup arrays")
-        blenderbim.core.spatial.import_spatial_decomposition(tool.Spatial)
+        tool.Spatial.run_spatial_import_spatial_decomposition()
+        if default_container := tool.Spatial.guess_default_container():
+            tool.Spatial.set_default_container(default_container)
         self.update_progress(100)
         bpy.context.window_manager.progress_end()
 

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

@@ -159,7 +159,6 @@ class BIM_OT_add_aggregate(bpy.types.Operator, tool.Ifc.Operator):
             if not element:
                 continue
 
-            tool.Collector.sync(obj)
             current_aggregate = ifcopenshell.util.element.get_aggregate(element)
             current_container = ifcopenshell.util.element.get_container(element)
             if current_aggregate:

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

@@ -122,8 +122,7 @@ class CreateProject(bpy.types.Operator):
                 bpy.data.meshes.remove(mesh)
             for mat in bpy.data.materials:
                 bpy.data.materials.remove(mat)
-        core.create_project(tool.Ifc, tool.Project, schema=props.export_schema, template=template)
-        blenderbim.core.spatial.import_spatial_decomposition(tool.Spatial)
+        core.create_project(tool.Ifc, tool.Project, tool.Spatial, schema=props.export_schema, template=template)
         tool.Blender.register_toolbar()
 
     def rollback(self, data):

src/blenderbim/blenderbim/core/project.py

@@ -25,7 +25,7 @@ if TYPE_CHECKING:
     import blenderbim.tool as tool
 
 
-def create_project(ifc: tool.Ifc, project: tool.Project, schema: str, template: Optional[str] = None) -> None:
+def create_project(ifc: tool.Ifc, project: tool.Project, spatial: tool.Spatial, schema: str, template: Optional[str] = None) -> None:
     if ifc.get():
         return
 
@@ -90,7 +90,10 @@ def create_project(ifc: tool.Ifc, project: tool.Project, schema: str, template:
     project.run_aggregate_assign_object(relating_obj=building, related_obj=storey)
 
     project.set_context(body)
-    project.set_active_spatial_element(storey)
+    spatial.run_spatial_import_spatial_decomposition()
+    if default_container := spatial.guess_default_container():
+        spatial.set_default_container(default_container)
+
     project.create_project_collections()
 
     if template:

src/blenderbim/blenderbim/core/root.py

@@ -67,7 +67,7 @@ def assign_class(
     predefined_type: Optional[str] = None,
     should_add_representation: bool = True,
     ifc_representation_class: Optional[str] = None,
-) -> ifcopenshell.entity_instance:
+) -> Optional[ifcopenshell.entity_instance]:
     """
     Args:
         context: is not optional if `should_add_representation` is True
@@ -86,6 +86,10 @@ def assign_class(
             obj=obj, context=context, ifc_representation_class=ifc_representation_class, profile_set_usage=None
         )
 
-    collector.sync(obj)
+    if default_container := root.get_default_container():
+        if root.is_spatial_element(element):
+            ifc.run("aggregate.assign_object", products=[element], relating_object=default_container)
+        elif root.is_containable(element):
+            ifc.run("spatial.assign_container", products=[element], relating_structure=default_container)
     collector.assign(obj)
     return element

src/blenderbim/blenderbim/core/spatial.py

@@ -86,7 +86,6 @@ def copy_to_container(ifc, collector, spatial, obj=None, containers=None):
     element = ifc.get_entity(obj)
     if not element:
         return
-    collector.sync(obj)
     from_container = spatial.get_container(element)
     if from_container:
         matrix = spatial.get_relative_object_matrix(obj, ifc.get_object(from_container))

src/blenderbim/blenderbim/core/tool.py

@@ -689,12 +689,15 @@ class Root:
     def copy_representation(cls, source, dest): pass
     def does_type_have_representations(cls, element): pass
     def get_decomposition_relationships(cls, objs): pass
+    def get_default_container(cls): pass
     def get_element_representation(cls, element, context): pass
     def get_element_type(cls, element): pass
     def get_object_name(cls, obj): pass
     def get_object_representation(cls, obj): pass
     def get_representation_context(cls, representation): pass
+    def is_containable(cls, element): pass
     def is_element_a(cls, element, ifc_class): pass
+    def is_spatial_element(cls, element): pass
     def link_object_data(cls, source_obj, destination_obj): pass
     def recreate_decompositions(cls, relationships, old_to_new): pass
     def run_geometry_add_representation(cls, obj=None, context=None, ifc_representation_class=None, profile_set_usage=None): pass
@@ -851,6 +854,7 @@ class Spatial:
     def import_spatial_decomposition(cls): pass
     def run_root_copy_class(cls, obj=None): pass
     def run_spatial_assign_container(cls, structure_obj=None, element_obj=None): pass
+    def run_spatial_import_spatial_decomposition(cls): pass
     def select_object(cls, obj): pass
     def select_products(cls, products, unhide=False): pass
     def set_active_object(cls, obj): pass

src/blenderbim/blenderbim/tool/collector.py

@@ -27,81 +27,6 @@ from typing import Union
 
 
 class Collector(blenderbim.core.tool.Collector):
-    @classmethod
-    def sync(cls, obj: bpy.types.Object, skip_unlinking=False) -> None:
-        """Sync object IFC state (assigned containter / aggregate) with the collection it's currently in.
-
-        Then subsequently run `Collector.assign` (if state has changed)
-        to link them to collections / unlink from anything unrelated collections.
-
-        If `skip_unlinking` is `True` then method won't try to assign parent object
-        if it's already assigned in IFC saving some time.
-        But it has a downside not unlinking object from unrelated collections.
-        """
-        # This is the reverse of assign. It reads the Blender collection and figures out its IFC hierarchy
-        element = tool.Ifc.get_entity(obj)
-
-        if (
-            not element
-            or element.is_a("IfcProject")
-            or element.is_a("IfcGridAxis")
-            or element.is_a("IfcOpeningElement")
-        ):
-            return
-
-        if not obj.users_collection:
-            return
-
-        # create related collections
-        cls._get_own_collection(element, obj)
-        cls._get_collection(element, obj)
-
-        parent_collection = None
-
-        for collection in obj.users_collection:
-            if parent_collection:
-                break
-            # skip Types and non-BIM collections
-            if not collection.BIMCollectionProperties.obj:
-                continue
-            # for objects that own collections we search for the first parent collection
-            if collection.BIMCollectionProperties.obj == obj:
-                collection_name = collection.name
-                for bpy_collection in bpy.data.collections:
-                    if bpy_collection.children.get(collection_name) and bpy_collection.BIMCollectionProperties.obj:
-                        parent_collection = bpy_collection
-                        parent_obj = bpy_collection.BIMCollectionProperties.obj
-                        break
-            else:
-                parent_collection = collection
-                parent_obj = collection.BIMCollectionProperties.obj
-
-        if not parent_collection:
-            return
-
-        parent = tool.Ifc.get_entity(parent_obj)
-        if skip_unlinking:
-            previous_parent = ifcopenshell.util.element.get_container(
-                element, should_get_direct=True
-            ) or ifcopenshell.util.element.get_aggregate(element)
-            if parent == previous_parent:
-                return
-
-        if parent:
-            # This is lazy, but works. One of these will succeed, the other will fail silently.
-            blenderbim.core.spatial.assign_container(
-                tool.Ifc, tool.Collector, tool.Spatial, structure_obj=parent_obj, element_obj=obj
-            )
-            # NOTE: won't allow assigning IfcElements to the IfcProject directly
-            # and some elements might get missing in other viewers if they're don't support displaying
-            # elements without hierarchy
-            try:
-                blenderbim.core.aggregate.assign_object(
-                    tool.Ifc, tool.Aggregate, tool.Collector, relating_obj=parent_obj, related_obj=obj
-                )
-            except blenderbim.core.aggregate.IncompatibleAggregateError:
-                pass
-
     @classmethod
     def assign(cls, obj: bpy.types.Object) -> None:
         """link object and it's owned collection to the proper collection

src/blenderbim/blenderbim/tool/root.py

@@ -98,6 +98,16 @@ class Root(blenderbim.core.tool.Root):
                 relationships[element] = {"type": "fill", "element": building}
         return relationships
 
+    @classmethod
+    def get_default_container(cls) -> Optional[ifcopenshell.entity_instance]:
+        props = bpy.context.scene.BIMSpatialDecompositionProperties
+        if container := props.default_container:
+            try:
+                return tool.Ifc.get().by_id(container)
+            except:
+                props.default_container = 0
+        return None
+
     @classmethod
     def get_connection_relationships(
         cls, objs: list[bpy.types.Object]
@@ -162,10 +172,20 @@ class Root(blenderbim.core.tool.Root):
     def get_representation_context(cls, representation: ifcopenshell.entity_instance) -> ifcopenshell.entity_instance:
         return representation.ContextOfItems
 
+    @classmethod
+    def is_containable(cls, element: ifcopenshell.entity_instance) -> bool:
+        return element.is_a("IfcElement") or element.is_a("IfcGrid")
+
     @classmethod
     def is_element_a(cls, element: ifcopenshell.entity_instance, ifc_class: str) -> bool:
         return element.is_a(ifc_class)
 
+    @classmethod
+    def is_spatial_element(cls, element: ifcopenshell.entity_instance) -> bool:
+        if tool.Ifc.get().schema == "IFC2X3":
+            return element.is_a("IfcSpatialStructureElement")
+        return element.is_a("IfcSpatialElement")
+
     @classmethod
     def link_object_data(cls, source_obj: bpy.types.Object, destination_obj: bpy.types.Object) -> None:
         destination_obj.data = source_obj.data

src/blenderbim/blenderbim/tool/spatial.py

@@ -30,8 +30,8 @@ import blenderbim.tool as tool
 import json
 from math import pi
 from mathutils import Vector, Matrix
-from shapely import Polygon, MultiPolygon
-from typing import Generator
+from shapely import Polygon
+from typing import Generator, Optional
 
 
 class Spatial(blenderbim.core.tool.Spatial):
@@ -134,6 +134,10 @@ class Spatial(blenderbim.core.tool.Spatial):
             tool.Ifc, tool.Collector, tool.Spatial, structure_obj=structure_obj, element_obj=element_obj
         )
 
+    @classmethod
+    def run_spatial_import_spatial_decomposition(cls):
+        return blenderbim.core.spatial.import_spatial_decomposition(tool.Spatial)
+
     @classmethod
     def select_object(cls, obj):
         obj.select_set(True)
@@ -445,7 +449,6 @@ class Spatial(blenderbim.core.tool.Spatial):
 
     @classmethod
     def get_x_y_z_h_mat_from_active_obj(cls, active_obj):
-        element = tool.Ifc.get_entity(active_obj)
         mat = active_obj.matrix_world
         local_bbox_center = 0.125 * sum((Vector(b) for b in active_obj.bound_box), Vector())
         global_bbox_center = mat @ local_bbox_center
@@ -518,14 +521,13 @@ class Spatial(blenderbim.core.tool.Spatial):
         project_unit = ifcopenshell.util.unit.get_project_unit(model, "LENGTHUNIT")
         prefix = getattr(project_unit, "Prefix", None)
 
-        converted_tolerance = ifcopenshell.util.unit.convert(
+        return ifcopenshell.util.unit.convert(
             value=tolerance,
             from_prefix=None,
             from_unit="METRE",
             to_prefix=prefix,
             to_unit=project_unit.Name,
         )
-        return tolerance
 
     @classmethod
     def get_purged_inner_holes_poly(cls, union_geom, min_area):
@@ -830,3 +832,19 @@ class Spatial(blenderbim.core.tool.Spatial):
     @classmethod
     def set_default_container(cls, container):
         bpy.context.scene.BIMSpatialDecompositionProperties.default_container = container.id()
+
+    @classmethod
+    def guess_default_container(cls) -> Optional[ifcopenshell.entity_instance]:
+        project = tool.Ifc.get().by_type("IfcProject")[0]
+        subelement = None
+        # We try to priorise the first Site > Building > Storey as a convention for vertical projects
+        for subelement in ifcopenshell.util.element.get_parts(project):
+            if subelement.is_a("IfcSite"):
+                for subelement2 in ifcopenshell.util.element.get_parts(subelement):
+                    if subelement2.is_a("IfcBuilding"):
+                        for subelement3 in ifcopenshell.util.element.get_parts(subelement2):
+                            if subelement3.is_a("IfcBuildingStorey"):
+                                return subelement3
+        if subelement:
+            return subelement
+        return None

src/blenderbim/test/core/test_spatial.py

@@ -80,7 +80,6 @@ class TestRemoveContainer:
 class TestCopyToContainer:
     def test_run(self, ifc, collector, spatial):
         ifc.get_entity("obj").should_be_called().will_return("element")
-        collector.sync("obj").should_be_called()
         spatial.get_container("element").should_be_called().will_return("container")
         ifc.get_object("container").should_be_called().will_return("container_obj")
         spatial.get_relative_object_matrix("obj", "container_obj").should_be_called().will_return("matrix")
@@ -97,7 +96,6 @@ class TestCopyToContainer:
 
     def test_using_an_absolute_matrix_if_there_is_no_from_container(self, ifc, collector, spatial):
         ifc.get_entity("obj").should_be_called().will_return("element")
-        collector.sync("obj").should_be_called()
         spatial.get_container("element").should_be_called().will_return(None)
         spatial.get_object_matrix("obj").should_be_called().will_return("matrix")