Optimise object placement change checking, so medium sized project exports are 5 seconds faster at minimum, but can be much higher since false positives are culled.

src/blenderbim/blenderbim/bim/export_ifc.py

@@ -132,6 +132,8 @@ class IfcExporter:
         return results
 
     def sync_object_placement(self, obj):
+        if not self.has_object_moved(obj):
+            return
         blender_matrix = np.array(obj.matrix_world)
         element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
         if (obj.scale - Vector((1.0, 1.0, 1.0))).length > 1e-4:
@@ -141,24 +143,19 @@ class IfcExporter:
             return self.sync_grid_axis_object_placement(obj, element)
         if not hasattr(element, "ObjectPlacement"):
             return
-        ifc_matrix = ifcopenshell.util.placement.get_local_placement(element.ObjectPlacement)
-        ifc_matrix[0][3] *= self.unit_scale
-        ifc_matrix[1][3] *= self.unit_scale
-        ifc_matrix[2][3] *= self.unit_scale
+        blenderbim.core.geometry.edit_object_placement(tool.Ifc, tool.Geometry, tool.Surveyor, obj=obj)
+        return element
 
-        props = bpy.context.scene.BIMGeoreferenceProperties
-        if props.has_blender_offset and obj.BIMObjectProperties.blender_offset_type == "OBJECT_PLACEMENT":
-            ifc_matrix = ifcopenshell.util.geolocation.global2local(
-                ifc_matrix,
-                float(props.blender_eastings) * self.unit_scale,
-                float(props.blender_northings) * self.unit_scale,
-                float(props.blender_orthogonal_height) * self.unit_scale,
-                float(props.blender_x_axis_abscissa),
-                float(props.blender_x_axis_ordinate),
-            )
-        if not np.allclose(ifc_matrix, blender_matrix, atol=0.0001):
-            blenderbim.core.geometry.edit_object_placement(tool.Ifc, tool.Geometry, tool.Surveyor, obj=obj)
-            return element
+    def has_object_moved(self, obj):
+        if not obj.BIMObjectProperties.location_checksum:
+            return True  # Let's be conservative
+        loc_check = np.frombuffer(eval(obj.BIMObjectProperties.location_checksum))
+        rot_check = np.frombuffer(eval(obj.BIMObjectProperties.rotation_checksum))
+        loc_real = np.array(obj.matrix_world.translation).flatten()
+        rot_real = np.array(obj.matrix_world.to_3x3()).flatten()
+        if np.allclose(loc_check, loc_real, atol=1e-4) and np.allclose(rot_check, rot_real, atol=1e-2):
+            return False
+        return True
 
     def sync_grid_axis_object_placement(self, obj, element):
         grid = (element.PartOfU or element.PartOfV or element.PartOfW)[0]

src/blenderbim/blenderbim/bim/import_ifc.py

@@ -31,6 +31,7 @@ import ifcopenshell.util.unit
 import ifcopenshell.util.element
 import ifcopenshell.util.selector
 import ifcopenshell.util.geolocation
+import blenderbim.tool as tool
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.module.drawing.prop import get_diagram_scales
 
@@ -509,7 +510,7 @@ class IfcImporter:
             mesh = self.create_mesh(axis, shape)
             obj = bpy.data.objects.new(f"IfcGridAxis/{axis.AxisTag}", mesh)
             self.link_element(axis, obj)
-            obj.matrix_world = grid_obj.matrix_world
+            self.set_matrix_world(obj, grid_obj.matrix_world)
             grid_collection.objects.link(obj)
 
     def create_type_products(self):
@@ -700,7 +701,7 @@ class IfcImporter:
             mesh.from_pydata([mathutils.Vector(vertex) * self.unit_scale], [], [])
 
             obj = bpy.data.objects.new("{}/{}".format(product.is_a(), product.Name), mesh)
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, placement_matrix)
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, placement_matrix))
             self.link_element(product, obj)
 
     def get_pointcloud_representation(self, product):
@@ -759,7 +760,7 @@ class IfcImporter:
         mesh.from_pydata(vertex_list, [], [])
 
         obj = bpy.data.objects.new("{}/{}".format(product.is_a(), product.Name), mesh)
-        obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, placement_matrix)
+        self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, placement_matrix))
         self.link_element(product, obj)
         return product
 
@@ -826,13 +827,13 @@ class IfcImporter:
             mat = np.array(
                 ([m[0], m[3], m[6], m[9]], [m[1], m[4], m[7], m[10]], [m[2], m[5], m[8], m[11]], [0, 0, 0, 1])
             )
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, mat)
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, mat))
             self.material_creator.create(element, obj, mesh)
         elif mesh:
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element))
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element)))
             self.material_creator.create(element, obj, mesh)
         elif hasattr(element, "ObjectPlacement"):
-            obj.matrix_world = self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element))
+            self.set_matrix_world(obj, self.apply_blender_offset_to_matrix_world(obj, self.get_element_matrix(element)))
 
         self.add_opening_relation(element, obj)
 
@@ -1518,6 +1519,10 @@ class IfcImporter:
         else:
             mesh.BIMMeshProperties.ifc_definition_id = int(geometry.id)
 
+    def set_matrix_world(self, obj, matrix_world):
+        obj.matrix_world = matrix_world
+        tool.Geometry.record_object_position(obj)
+
 
 class IfcImportSettings:
     def __init__(self):

src/blenderbim/blenderbim/bim/prop.py

@@ -318,9 +318,8 @@ class BIMObjectProperties(PropertyGroup):
         default="NONE",
     )
     is_reassigning_class: BoolProperty(name="Is Reassigning Class")
-    global_ids: CollectionProperty(name="GlobalIds", type=GlobalId)
-    psets: CollectionProperty(name="Psets", type=PsetQto)
-    qtos: CollectionProperty(name="Qtos", type=PsetQto)
+    location_checksum: StringProperty(name="Location Checksum")
+    rotation_checksum: StringProperty(name="Rotation Checksum")
 
 
 class BIMMaterialProperties(PropertyGroup):

src/blenderbim/blenderbim/core/geometry.py

@@ -25,6 +25,7 @@ def edit_object_placement(ifc, geometry, surveyor, obj=None):
         geometry.clear_cache(element)
         geometry.clear_scale(obj)
         ifc.run("geometry.edit_object_placement", product=element, matrix=surveyor.get_absolute_matrix(obj))
+        geometry.record_object_position(obj)
 
 
 def add_representation(

src/blenderbim/blenderbim/core/tool.py

@@ -100,6 +100,7 @@ class Geometry:
     def is_mapped_representation(cls, representation): pass
     def is_type_product(cls, element): pass
     def link(cls, element, obj): pass
+    def record_object_position(cls, obj): pass
     def rename_object(cls, obj, name): pass
     def replace_object_with_empty(cls, obj): pass
     def resolve_mapped_representation(cls, representation): pass

src/blenderbim/blenderbim/tool/geometry.py

@@ -18,6 +18,7 @@
 
 import bpy
 import logging
+import numpy as np
 import ifcopenshell
 import blenderbim.core.tool
 import blenderbim.core.style
@@ -223,6 +224,12 @@ class Geometry(blenderbim.core.tool.Geometry):
     def link(cls, element, obj):
         obj.BIMMeshProperties.ifc_definition_id = element.id()
 
+    @classmethod
+    def record_object_position(cls, obj):
+        # These are recorded separately because they have different numerical tolerances
+        obj.BIMObjectProperties.location_checksum = repr(np.array(obj.matrix_world.translation).tobytes())
+        obj.BIMObjectProperties.rotation_checksum = repr(np.array(obj.matrix_world.to_3x3()).tobytes())
+
     @classmethod
     def rename_object(cls, obj, name):
         obj.name = name

src/blenderbim/test/core/test_geometry.py

@@ -28,6 +28,7 @@ class TestEditObjectPlacement:
         geometry.clear_scale("obj").should_be_called()
         surveyor.get_absolute_matrix("obj").should_be_called().will_return("matrix")
         ifc.run("geometry.edit_object_placement", product="element", matrix="matrix").should_be_called()
+        geometry.record_object_position("obj").should_be_called()
 
     def test_run(self, ifc, geometry, surveyor):
         self.predict(ifc, geometry, surveyor)

src/blenderbim/test/tool/test_geometry.py

@@ -18,7 +18,7 @@
 
 import bpy
 import math
-import numpy
+import numpy as np
 import ifcopenshell
 import blenderbim.core.tool
 import blenderbim.tool as tool
@@ -352,6 +352,14 @@ class TestLink(NewFile):
         assert obj.BIMMeshProperties.ifc_definition_id == element.id()
 
 
+class TestRecordObjectPosition(NewFile):
+    def test_run(self):
+        obj = bpy.data.objects.new("Object", None)
+        subject.record_object_position(obj)
+        assert obj.BIMObjectProperties.location_checksum == repr(np.array(obj.matrix_world.translation).tobytes())
+        assert obj.BIMObjectProperties.rotation_checksum == repr(np.array(obj.matrix_world.to_3x3()).tobytes())
+
+
 class TestRenameObject(NewFile):
     def test_run(self):
         obj = bpy.data.meshes.new("Mesh")