UV coordinates for triangulated face sets are now saved in IFC.

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

@@ -188,8 +188,9 @@ class UpdateRepresentation(bpy.types.Operator):
             "geometry": obj.data,
             "coordinate_offset": coordinate_offset,
             "total_items": max(1, len(obj.material_slots)),
-            "should_force_faceted_brep": context.scene.BIMGeometryProperties.should_force_faceted_brep,
-            "should_force_triangulation": context.scene.BIMGeometryProperties.should_force_triangulation,
+            "should_force_faceted_brep": tool.Geometry.should_force_faceted_brep(),
+            "should_force_triangulation": tool.Geometry.should_force_triangulation(),
+            "should_generate_uvs": tool.Geometry.should_generate_uvs(obj),
             "ifc_representation_class": self.ifc_representation_class,
         }
 

src/blenderbim/blenderbim/core/geometry.py

@@ -50,6 +50,7 @@ def add_representation(
         total_items=geometry.get_total_representation_items(obj),
         should_force_faceted_brep=geometry.should_force_faceted_brep(),
         should_force_triangulation=geometry.should_force_triangulation(),
+        should_generate_uvs=geometry.should_generate_uvs(obj),
         ifc_representation_class=ifc_representation_class,
         profile_set_usage=profile_set_usage,
     )

src/blenderbim/blenderbim/core/tool.py

@@ -217,6 +217,7 @@ class Geometry:
     def run_style_add_style(cls, obj=None): pass
     def should_force_faceted_brep(cls): pass
     def should_force_triangulation(cls): pass
+    def should_generate_uvs(cls, obj): pass
     def should_use_presentation_style_assignment(cls): pass
 
 

src/blenderbim/blenderbim/tool/geometry.py

@@ -298,6 +298,15 @@ class Geometry(blenderbim.core.tool.Geometry):
     def should_force_triangulation(cls):
         return bpy.context.scene.BIMGeometryProperties.should_force_triangulation
 
+    @classmethod
+    def should_generate_uvs(cls, obj):
+        for slot in obj.material_slots:
+            if slot.material and slot.material.use_nodes:
+                for node in slot.material.node_tree.nodes:
+                    if node.type == "TEX_COORD" and node.outputs['UV'].links:
+                        return True
+        return False
+
     @classmethod
     def should_use_presentation_style_assignment(cls):
         return bpy.context.scene.BIMGeometryProperties.should_use_presentation_style_assignment

src/blenderbim/test/core/test_geometry.py

@@ -45,6 +45,7 @@ class TestAddRepresentation:
         geometry.get_total_representation_items("obj").should_be_called().will_return(1)
         geometry.should_force_faceted_brep().should_be_called().will_return(False)
         geometry.should_force_triangulation().should_be_called().will_return(True)
+        geometry.should_generate_uvs("obj").should_be_called().will_return(True)
         ifc.run(
             "geometry.add_representation",
             context="context",
@@ -54,6 +55,7 @@ class TestAddRepresentation:
             total_items=1,
             should_force_faceted_brep=False,
             should_force_triangulation=True,
+            should_generate_uvs=True,
             ifc_representation_class="ifc_representation_class",
             profile_set_usage="profile_set_usage",
         ).should_be_called().will_return("representation")
@@ -109,6 +111,7 @@ class TestAddRepresentation:
         geometry.get_total_representation_items("obj").should_be_called().will_return(1)
         geometry.should_force_faceted_brep().should_be_called().will_return(False)
         geometry.should_force_triangulation().should_be_called().will_return(True)
+        geometry.should_generate_uvs("obj").should_be_called().will_return(True)
         ifc.run(
             "geometry.add_representation",
             context="context",
@@ -118,6 +121,7 @@ class TestAddRepresentation:
             total_items=1,
             should_force_faceted_brep=False,
             should_force_triangulation=True,
+            should_generate_uvs=True,
             ifc_representation_class="ifc_representation_class",
             profile_set_usage="profile_set_usage",
         ).should_be_called().will_return("representation")

src/blenderbim/test/tool/test_geometry.py

@@ -462,6 +462,33 @@ class TestShouldForceTriangulation(NewFile):
         assert subject.should_force_triangulation() is result
 
 
+class TestShouldGenerateUVs(NewFile):
+    def test_needs_mesh_data(self):
+        obj = bpy.data.objects.new("Object", None)
+        assert subject.should_generate_uvs(obj) is False
+
+    def test_needs_nodes(self):
+        obj = bpy.data.objects.new("Object", bpy.data.meshes.new("Mesh"))
+        material = bpy.data.materials.new("Material")
+        obj.data.materials.append(material)
+        material.use_nodes = False
+        assert subject.should_generate_uvs(obj) is False
+
+    def test_needs_texture_coordinates_with_a_uv_output(self):
+        obj = bpy.data.objects.new("Object", bpy.data.meshes.new("Mesh"))
+        material = bpy.data.materials.new("Material")
+        obj.data.materials.append(material)
+        material.use_nodes = True
+
+        bsdf = material.node_tree.nodes["Principled BSDF"]
+        node = material.node_tree.nodes.new(type="ShaderNodeTexImage")
+        material.node_tree.links.new(bsdf.inputs["Base Color"], node.outputs["Color"])
+
+        coords = material.node_tree.nodes.new(type="ShaderNodeTexCoord")
+        material.node_tree.links.new(node.inputs["Vector"], coords.outputs["UV"])
+        assert subject.should_generate_uvs(obj) is True
+
+
 class TestShouldUsePresentationStyleAssignment(NewFile):
     def test_run(self):
         result = bpy.context.scene.BIMGeometryProperties.should_use_presentation_style_assignment

src/ifcopenshell-python/ifcopenshell/api/geometry/add_representation.py

@@ -40,6 +40,7 @@ class Usecase:
             "unit_scale": None,  # A scale factor to apply for all vectors in case the unit is different
             "should_force_faceted_brep": False,  # If we should force faceted breps for meshes
             "should_force_triangulation": False,  # If we should force triangulation for meshes
+            "should_generate_uvs": False,  # If UV coordinates should also be generated
             #  Possible IFC representation classes:
             #  IfcExtrudedAreaSolid/IfcRectangleProfileDef
             #  IfcExtrudedAreaSolid/IfcCircleProfileDef
@@ -505,16 +506,43 @@ class Usecase:
 
     def create_triangulated_face_set(self):
         ifc_raw_items = [None] * self.settings["total_items"]
+        if self.settings["should_generate_uvs"]:
+            ifc_raw_uv_items = [None] * self.settings["total_items"]
         for i, value in enumerate(ifc_raw_items):
             ifc_raw_items[i] = []
+            if self.settings["should_generate_uvs"]:
+                ifc_raw_uv_items[i] = []
         for polygon in self.settings["geometry"].polygons:
             ifc_raw_items[polygon.material_index % self.settings["total_items"]].append(
                 [v + 1 for v in polygon.vertices]
             )
+            if self.settings["should_generate_uvs"]:
+                ifc_raw_uv_items[polygon.material_index % self.settings["total_items"]].append(
+                    [uv + 1 for uv in polygon.loop_indices]
+                )
+
         coordinates = self.file.createIfcCartesianPointList3D(
             [self.convert_si_to_unit(v.co) for v in self.settings["geometry"].vertices]
         )
-        items = [self.file.createIfcTriangulatedFaceSet(coordinates, None, None, i) for i in ifc_raw_items if i]
+
+        if self.settings["should_generate_uvs"]:
+            # Blender supports multiple UV layers. We don't. Too bad.
+            tex_coords = self.file.createIfcTextureVertexList(
+                [tuple(x.uv) for x in self.settings["geometry"].uv_layers[0].data]
+            )
+            items = []
+            for i, coord_index in enumerate(ifc_raw_items):
+                if not coord_index:
+                    continue
+                tex_coords_index = ifc_raw_uv_items[i]
+                face_set = self.file.createIfcTriangulatedFaceSet(coordinates, None, None, coord_index)
+                texture_map = self.file.createIfcIndexedTriangleTextureMap(
+                    MappedTo=face_set, TexCoords=tex_coords, TexCoordIndex=tex_coords_index
+                )
+                items.append(face_set)
+        else:
+            items = [self.file.createIfcTriangulatedFaceSet(coordinates, None, None, i) for i in ifc_raw_items if i]
+
         return self.file.createIfcShapeRepresentation(
             self.settings["context"],
             self.settings["context"].ContextIdentifier,