Very minimal implementation of generating parametric duct segments from duct size properties

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

@@ -0,0 +1,109 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2020, 2021 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+import math
+import bmesh
+import ifcopenshell
+import ifcopenshell.api
+import ifcopenshell.util.unit
+import ifcopenshell.util.element
+import ifcopenshell.util.representation
+import mathutils.geometry
+import blenderbim.bim.handler
+import blenderbim.core.type
+import blenderbim.core.root
+import blenderbim.core.geometry
+import blenderbim.tool as tool
+from math import pi, degrees
+from mathutils import Vector, Matrix
+
+
+
+class MepGenerator:
+    def __init__(self, relating_type):
+        self.relating_type = relating_type
+
+    def generate(self):
+        self.file = tool.Ifc.get()
+        self.collection = bpy.context.view_layer.active_layer_collection.collection
+
+        if self.relating_type.is_a("IfcCableCarrierSegmentType"):
+            pass
+        elif self.relating_type.is_a("IfcCableSegmentType"):
+            pass
+        elif self.relating_type.is_a("IfcDuctSegmentType"):
+            dimensions = ifcopenshell.util.element.get_psets(self.relating_type).get("Pset_DuctSegmentTypeCommon") or {}
+            shape = dimensions.get("Shape") or dimensions.get("CrossSectionShape")
+
+            if shape == "RECTANGULAR":
+                self.width = dimensions.get("NominalDiameterOrWidth")
+                self.height = dimensions.get("NominalHeight")
+                self.length = 1
+                self.rotation = 0
+
+                return self.derive_from_cursor()
+        elif self.relating_type.is_a("IfcPipeSegmentType"):
+            pass
+
+    def derive_from_cursor(self):
+        self.location = bpy.context.scene.cursor.location
+        return self.create_rectangle_segment()
+
+    def create_rectangle_segment(self):
+        verts = [
+            Vector((0, self.width, 0)),
+            Vector((0, 0, 0)),
+            Vector((0, self.width, self.height)),
+            Vector((0, 0, self.height)),
+            Vector((self.length, self.width, 0)),
+            Vector((self.length, 0, 0)),
+            Vector((self.length, self.width, self.height)),
+            Vector((self.length, 0, self.height)),
+        ]
+        faces = [
+            [1, 3, 2, 0],
+            [4, 6, 7, 5],
+            [1, 0, 4, 5],
+            [3, 7, 6, 2],
+            [0, 2, 6, 4],
+            [1, 5, 7, 3],
+        ]
+        mesh = bpy.data.meshes.new(name="Segment")
+        mesh.from_pydata(verts, [], faces)
+
+        ifc_classes = ifcopenshell.util.type.get_applicable_entities(self.relating_type.is_a(), self.file.schema)
+        ifc_class = ifc_classes[0]
+
+        obj = bpy.data.objects.new(tool.Model.generate_occurrence_name(self.relating_type, ifc_class), mesh)
+        obj.location = self.location
+        obj.rotation_euler[2] = self.rotation
+        self.collection.objects.link(obj)
+
+        bpy.ops.bim.assign_class(
+            obj=obj.name,
+            ifc_class=ifc_class,
+            ifc_representation_class="IfcExtrudedAreaSolid/IfcRectangleProfileDef",
+        )
+
+        blenderbim.core.type.assign_type(tool.Ifc, tool.Type, element=tool.Ifc.get_entity(obj), type=self.relating_type)
+        element = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        pset = ifcopenshell.api.run("pset.add_pset", self.file, product=element, name="EPset_Parametric")
+        ifcopenshell.api.run("pset.edit_pset", self.file, pset=pset, properties={"Engine": "BlenderBIM.Mep"})
+        obj.select_set(True)
+        return obj

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

@@ -25,7 +25,7 @@ import ifcopenshell.util.representation
 import blenderbim.tool as tool
 import blenderbim.core.type
 import blenderbim.core.geometry
-from . import wall, slab, profile
+from . import wall, slab, profile, mep
 from blenderbim.bim.ifc import IfcStore
 from ifcopenshell.api.pset.data import Data as PsetData
 from mathutils import Vector, Matrix
@@ -81,6 +81,9 @@ class AddTypeInstance(bpy.types.Operator):
         elif material and material.is_a("IfcMaterialLayerSet"):
             if self.generate_layered_element(ifc_class, relating_type):
                 return {"FINISHED"}
+        if relating_type.is_a("IfcFlowSegmentType"):
+            if mep.MepGenerator(relating_type).generate():
+                return {"FINISHED"}
 
         building_obj = None
         if len(context.selected_objects) == 1 and context.active_object: