New hacktastic IFC patch to fix ArchiCAD spaces being loaded into Revit.

src/ifcpatch/ifcpatch/recipes/FixArchiCADToRevitSpaces.py

@@ -0,0 +1,79 @@
+class Patcher:
+    def __init__(self, src, file, logger, args=None):
+        self.src = src
+        self.file = file
+        self.logger = logger
+        self.args = args
+
+    def patch(self):
+        # The underlying problem is that Revit does not bring in IFC spaces as
+        # spaces / rooms in Revit when you link an IFC in Revit. This has been
+        # broken for at least 3 years and counting. This is a problem typically
+        # for ArchiCAD architects who want to send rooms to MEP folks using
+        # Revit.
+        #
+        # See bug: https://github.com/Autodesk/revit-ifc/issues/15
+        #
+        # The solution is to open an IFC in Revit instead of linking it, which
+        # will convert IFC spaces into Revit rooms. However, there are very
+        # specific scenarios where Revit will convert these rooms, which have
+        # been painstakingly reverse engineered through trial and error.
+        # Firstly, the rooms should have a lower bound with a Z value matching
+        # the Z value of the storey it is on. Secondly, although faceted breps
+        # do work in some scenarios (I assume Revit has an internal topological
+        # analysis tool), conversion to an extruded area solid yield much more
+        # robust results. Finally, changing the Precision value to an obscene
+        # number very strangely seems to cause a lot more rooms to be converted
+        # successfully.
+        #
+        # This patch is designed to only work on ArchiCAD IFC exports where the
+        # only contents of the IFC is IFC space and _nothing else_. It also
+        # requires you to run it using Blender, as the geometric modification
+        # uses the Blender geometry engine.
+        import bpy
+        from blenderbim.bim.ifc import IfcStore
+        from mathutils import Vector, Matrix
+
+        if len(bpy.data.objects) > 0:
+            while bpy.data.objects:
+                bpy.data.objects.remove(bpy.data.objects[0])
+            bpy.ops.outliner.orphans_purge(do_local_ids=True, do_linked_ids=True, do_recursive=True)
+
+        bpy.ops.bim.load_project(filepath=self.src)
+
+        def recalculate_origin(wall):
+            new_origin = wall.matrix_world @ Vector(wall.bound_box[0])
+            if (wall.matrix_world.translation - new_origin).length < 0.001:
+                return
+            wall.data.transform(
+                Matrix.Translation(
+                    (wall.matrix_world.inverted().to_quaternion() @ (wall.matrix_world.translation - new_origin))
+                )
+            )
+            wall.matrix_world.translation = new_origin
+
+        for obj in bpy.context.visible_objects:
+            if "IfcBuildingStorey" in obj.name and len(bpy.data.collections.get(obj.name).children) > 0:
+                target_z = obj.location.z
+
+        for obj in bpy.context.visible_objects:
+            bpy.context.view_layer.update()
+            if "IfcSpace" not in obj.name:
+                continue
+            local_target_z = (obj.matrix_world.inverted() @ Vector((0, 0, target_z))).z
+            local_target_zup = (obj.matrix_world.inverted() @ Vector((0, 0, target_z + 3))).z
+            for v in obj.data.vertices:
+                if round(v.co.z, 3) == 0:
+                    v.co.z = local_target_z
+            bpy.context.view_layer.update()
+            recalculate_origin(obj)
+            obj.select_set(True)
+
+        bpy.ops.bim.update_representation(
+            ifc_representation_class="IfcExtrudedAreaSolid/IfcArbitraryProfileDefWithVoids"
+        )
+        for context in IfcStore.get_file().by_type("IfcGeometricRepresentationContext"):
+            if context.Precision:
+                context.Precision = 10
+
+        self.file = IfcStore.get_file()