Fix bug where adding an opening didn't create a relative placement

src/ifcopenshell-python/ifcopenshell/api/void/add_opening.py

@@ -44,3 +44,13 @@ class Usecase:
                 "RelatedOpeningElement": self.settings["opening"],
             }
         )
+
+        placement = getattr(self.settings["opening"], "ObjectPlacement", None)
+        if placement and placement.is_a("IfcLocalPlacement"):
+            ifcopenshell.api.run(
+                "geometry.edit_object_placement",
+                self.file,
+                product=self.settings["opening"],
+                matrix=ifcopenshell.util.placement.get_local_placement(self.settings["opening"].ObjectPlacement),
+                is_si=False,
+            )

src/ifcopenshell-python/test/api/void/test_add_opening.py

@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
+import numpy
 import test.bootstrap
 import ifcopenshell.api
 
@@ -43,3 +44,36 @@ class TestAddOpening(test.bootstrap.IFC4):
         ifcopenshell.api.run("void.add_opening", self.file, opening=opening, element=wall)
         assert not slab.HasOpenings
         assert wall.HasOpenings[0].RelatedOpeningElement == opening
+
+    def test_assigning_an_opening_does_not_shift_object_placements(self):
+        ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcProject")
+        ifcopenshell.api.run("unit.assign_unit", self.file)
+        wall = ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcWall")
+        opening = ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcOpeningElement")
+        matrix1 = numpy.array(
+            (
+                (1.0, 0.0, 0.0, 1.0),
+                (0.0, 1.0, 0.0, 1.0),
+                (0.0, 0.0, 1.0, 1.0),
+                (0.0, 0.0, 0.0, 1.0),
+            )
+        )
+        ifcopenshell.api.run(
+            "geometry.edit_object_placement", self.file, product=wall, matrix=matrix1.copy(), is_si=False
+        )
+        ifcopenshell.api.run(
+            "geometry.edit_object_placement", self.file, product=opening, matrix=matrix1.copy(), is_si=False
+        )
+        ifcopenshell.api.run("void.add_opening", self.file, opening=opening, element=wall)
+        assert opening.ObjectPlacement.PlacementRelTo.PlacesObject[0] == wall
+        assert numpy.array_equal(ifcopenshell.util.placement.get_local_placement(opening.ObjectPlacement), matrix1)
+
+    def test_not_updating_placement_if_placement_is_not_relative(self):
+        ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcProject")
+        ifcopenshell.api.run("unit.assign_unit", self.file)
+        wall = ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcWall")
+        opening = ifcopenshell.api.run("root.create_entity", self.file, ifc_class="IfcOpeningElement")
+        placement = self.file.createIfcGridPlacement()
+        opening.ObjectPlacement = placement
+        ifcopenshell.api.run("void.add_opening", self.file, opening=opening, element=wall)
+        assert opening.ObjectPlacement == placement