Implement faux-mirroring.

src/blenderbim/blenderbim/bim/module/geometry/__init__.py

@@ -59,6 +59,7 @@ def register():
     if wm.keyconfigs.addon:
         km = wm.keyconfigs.addon.keymaps.new(name="Object Mode", space_type="EMPTY")
         kmi = km.keymap_items.new("bim.override_object_duplicate_move", "D", "PRESS", shift=True)
+        kmi.properties.is_interactive = True
         kmi = km.keymap_items.new("bim.override_object_duplicate_move_linked", "D", "PRESS", alt=True)
         kmi = km.keymap_items.new("bim.override_paste_buffer", "V", "PRESS", ctrl=True)
         kmi = km.keymap_items.new("bim.override_mode_set_edit", "TAB", "PRESS")

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

@@ -502,6 +502,7 @@ class OverrideDuplicateMove(bpy.types.Operator):
     bl_idname = "bim.override_object_duplicate_move"
     bl_label = "IFC Duplicate Objects"
     bl_options = {"REGISTER", "UNDO"}
+    is_interactive: bpy.props.BoolProperty(name="Is Interactive", default=True)
 
     @classmethod
     def poll(cls, context):
@@ -528,7 +529,8 @@ class OverrideDuplicateMove(bpy.types.Operator):
             new_obj.select_set(True)
         if new_active_obj:
             context.view_layer.objects.active = new_active_obj
-        bpy.ops.transform.translate("INVOKE_DEFAULT")
+        if self.is_interactive:
+            bpy.ops.transform.translate("INVOKE_DEFAULT")
         return {"FINISHED"}
 
     def _execute(self, context):
@@ -552,7 +554,8 @@ class OverrideDuplicateMove(bpy.types.Operator):
                 old_to_new[tool.Ifc.get_entity(obj)] = [new]
         # Recreate decompositions
         tool.Root.recreate_decompositions(relationships, old_to_new)
-        bpy.ops.transform.translate("INVOKE_DEFAULT")
+        if self.is_interactive:
+            bpy.ops.transform.translate("INVOKE_DEFAULT")
         blenderbim.bim.handler.purge_module_data()
 
 

src/blenderbim/blenderbim/bim/module/model/__init__.py

@@ -52,6 +52,7 @@ classes = (
     product.AlignProduct,
     product.ChangeTypePage,
     product.LoadTypeThumbnails,
+    product.MirrorElements,
     workspace.Hotkey,
     wall.AlignWall,
     wall.ChangeExtrusionDepth,

src/blenderbim/blenderbim/bim/module/model/product.py

@@ -398,6 +398,64 @@ class LoadTypeThumbnails(bpy.types.Operator, tool.Ifc.Operator):
         return {"FINISHED"}
 
 
+class MirrorElements(bpy.types.Operator, tool.Ifc.Operator):
+    bl_idname = "bim.mirror_elements"
+    bl_label = "Mirror Elements"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Faux-mirrors the selected object by an active empty along a mirror plane."
+
+    @classmethod
+    def poll(cls, context):
+        return context.selected_objects
+
+    def _execute(self, context):
+        # This is not a true mirror operation. In BIM, objects that are
+        # mirrored are not the same type. (i.e. a mirrored asymmetric desk is a
+        # completely different product). To preserve types, we calculate
+        # bounding box centroids, and mirror the position of the object.  The
+        # mirrored object performs the necessary rotation to preserve the
+        # mirrored intention, but never actually truly mirror anything (i.e.
+        # scale = -1).
+
+        # Objects are mirrored along the YZ plane of the mirror object.
+        # Mirrored objects have their relative local Y and Z axes preserved,
+        # and the new X axis is calculated.
+
+        # In theory, untyped objects may be truly mirrored, but this is not yet
+        # implemented.
+        mirror = context.active_object
+        reflection = Matrix()
+        reflection[0][0] = -1
+
+        mirror.select_set(False)
+
+        bpy.ops.bim.override_object_duplicate_move(is_interactive=False)
+
+        for obj in context.selected_objects:
+            if obj == mirror:
+                continue
+
+            objmat = mirror.matrix_world.inverted() @ obj.matrix_world.copy()
+            x, y, z = objmat.to_3x3().col
+            centroid = Vector(obj.bound_box[0]).lerp(Vector(obj.bound_box[6]), 0.5)
+            c = mirror.matrix_world.inverted() @ obj.matrix_world @ centroid
+            newy = mirror.matrix_world.to_quaternion() @ (y @ reflection)
+            newz = mirror.matrix_world.to_quaternion() @ (z @ reflection)
+            newx = newy.cross(newz)
+            newc = mirror.matrix_world @ (c @ reflection)
+
+            newmat = Matrix((newx.to_4d(), newy.to_4d(), newz.to_4d(), newc.to_4d())).transposed()
+            newmat.col[3][0:3] = Vector(newmat.col[3][0:3]) - (newmat.to_quaternion() @ centroid)
+
+            obj.matrix_world = newmat
+
+    def copy_obj(self, obj):
+        new = obj.copy()
+        new.data = wall2.data.copy()
+        wall1.users_collection[0].objects.link(wall2)
+        blenderbim.core.root.copy_class(tool.Ifc, tool.Collector, tool.Geometry, tool.Root, obj=wall2)
+
+
 def generate_box(usecase_path, ifc_file, settings):
     box_context = ifcopenshell.util.representation.get_context(ifc_file, "Model", "Box", "MODEL_VIEW")
     if not box_context:

src/blenderbim/blenderbim/bim/module/model/workspace.py

@@ -368,6 +368,8 @@ class BimToolUI:
         row.label(text="", icon="EVENT_SHIFT")
         row.label(text="Align Interior", icon="EVENT_V")
         row = cls.layout.row(align=True)
+        row.label(text="", icon="EVENT_SHIFT")
+        row.label(text="Mirror", icon="EVENT_M")
 
         row = cls.layout.row(align=True)
         row.label(text="Mode")
@@ -606,6 +608,8 @@ class Hotkey(bpy.types.Operator, tool.Ifc.Operator):
             return
         if self.active_material_usage == "LAYER2":
             bpy.ops.bim.merge_wall()
+        else:
+            bpy.ops.bim.mirror_elements()
 
     def hotkey_S_R(self):
         if not bpy.context.selected_objects: