Object placements are now updated on export in case you forgot to sync them in authoring mode. See #1360.

src/ifcblenderexport/blenderbim/bim/export_ifc.py

@@ -1,10 +1,12 @@
 import os
 import bpy
 import json
+import numpy as np
 import datetime
 import zipfile
 import tempfile
 import ifcopenshell
+import ifcopenshell.util.placement
 from blenderbim.bim.ifc import IfcStore
 import addon_utils
 
@@ -16,6 +18,8 @@ class IfcExporter:
     def export(self):
         self.file = IfcStore.get_file()
         self.set_header()
+        if bpy.context.scene.BIMProjectProperties.is_authoring:
+            self.sync_object_placements()
         extension = self.ifc_export_settings.output_file.split(".")[-1]
         if extension == "ifczip":
             with tempfile.TemporaryDirectory() as unzipped_path:
@@ -68,6 +72,36 @@ class IfcExporter:
         # else:
         #    self.file.wrapped_data.header.file_name.authorization = "Nobody"
 
+    def sync_object_placements(self):
+        self.unit_scale = ifcopenshell.util.unit.calculate_unit_scale(self.file)
+        for obj in bpy.data.objects:
+            try:
+                self.sync_object_placement(obj)
+            except:
+                pass
+
+    def sync_object_placement(self, obj):
+        blender_matrix = np.matrix(obj.matrix_world)
+        ifc_matrix = ifcopenshell.util.placement.get_local_placement(
+            self.file.by_id(obj.BIMObjectProperties.ifc_definition_id).ObjectPlacement
+        )
+        ifc_matrix[0][3] *= self.unit_scale
+        ifc_matrix[1][3] *= self.unit_scale
+        ifc_matrix[2][3] *= self.unit_scale
+
+        props = bpy.context.scene.BIMGeoreferenceProperties
+        if props.has_blender_offset and props.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):
+            bpy.ops.bim.edit_object_placement(obj=obj.name)
+
     def get_application_name(self):
         return "BlenderBIM"
 

src/ifcblenderexport/blenderbim/bim/module/geometry/operator.py

@@ -1,6 +1,7 @@
 import bpy
 import numpy as np
 import ifcopenshell
+import ifcopenshell.util.unit
 import ifcopenshell.util.element
 import logging
 import blenderbim.bim.module.geometry.edit_object_placement as edit_object_placement
@@ -37,19 +38,19 @@ class EditObjectPlacement(bpy.types.Operator):
         self.file = IfcStore.get_file()
         # TODO: determine how to deal with this module dependency
         props = bpy.context.scene.BIMGeoreferenceProperties
+        unit_scale = ifcopenshell.util.unit.calculate_unit_scale(self.file)
         for obj in objs:
             if not obj.BIMObjectProperties.ifc_definition_id:
                 continue
             matrix = np.array(obj.matrix_world)
             if props.has_blender_offset and props.blender_offset_type == "OBJECT_PLACEMENT":
-                self.calculate_unit_scale()
                 # TODO: np.array? Why not matrix?
                 matrix = np.array(
                     ifcopenshell.util.geolocation.local2global(
                         np.matrix(obj.matrix_world),
-                        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_eastings) * unit_scale,
+                        float(props.blender_northings) * unit_scale,
+                        float(props.blender_orthogonal_height) * unit_scale,
                         float(props.blender_x_axis_abscissa),
                         float(props.blender_x_axis_ordinate),
                     )
@@ -63,18 +64,6 @@ class EditObjectPlacement(bpy.types.Operator):
             ).execute()
         return {"FINISHED"}
 
-    def calculate_unit_scale(self):
-        self.unit_scale = 1
-        units = self.file.by_type("IfcUnitAssignment")[0]
-        for unit in units.Units:
-            if not hasattr(unit, "UnitType") or unit.UnitType != "LENGTHUNIT":
-                continue
-            while unit.is_a("IfcConversionBasedUnit"):
-                self.unit_scale *= unit.ConversionFactor.ValueComponent.wrappedValue
-                unit = unit.ConversionFactor.UnitComponent
-            if unit.is_a("IfcSIUnit"):
-                self.unit_scale *= ifcopenshell.util.unit.get_prefix_multiplier(unit.Prefix)
-
 
 class AddRepresentation(bpy.types.Operator):
     bl_idname = "bim.add_representation"

src/ifcblenderexport/blenderbim/bim/module/project/prop.py

@@ -13,4 +13,4 @@ from bpy.props import (
 
 
 class BIMProjectProperties(PropertyGroup):
-    is_authoring: BoolProperty(name="Enable Authoring Mode")
+    is_authoring: BoolProperty(name="Enable Authoring Mode", default=True)