surface style ids on serialization

src/ifcgeom/IfcGeomRepresentation.cpp

@@ -36,21 +36,28 @@ IfcGeom::Representation::Serialization::Serialization(const BRep& brep)
 {
 	TopoDS_Compound compound = brep.as_compound();
 	for (IfcGeom::IfcRepresentationShapeItems::const_iterator it = brep.begin(); it != brep.end(); ++ it) {
+		int sid = -1;
+		
 		if (it->hasStyle() && it->Style().Diffuse()) {
 			const IfcGeom::SurfaceStyle::ColorComponent& clr = *it->Style().Diffuse();
 			surface_styles_.push_back(clr.R());
 			surface_styles_.push_back(clr.G());
 			surface_styles_.push_back(clr.B());
+
+			sid = it->Style().Id().get_value_or(-1);
 		} else {
 			surface_styles_.push_back(-1.);
 			surface_styles_.push_back(-1.);
 			surface_styles_.push_back(-1.);
 		}
+
 		if (it->hasStyle() && it->Style().Transparency()) {
 			surface_styles_.push_back(1. - *it->Style().Transparency());
 		} else {
 			surface_styles_.push_back(1.);
 		}
+
+		surface_style_ids_.push_back(sid);
 	}
 	std::stringstream sstream;
 	BRepTools::Write(compound,sstream);

src/ifcgeom/IfcGeomRepresentation.h

@@ -87,9 +87,11 @@ namespace IfcGeom {
 			std::string id_;
 			std::string brep_data_;
 			std::vector<double> surface_styles_;
+			std::vector<int> surface_style_ids_;
 		public:
 			const std::string& brep_data() const { return brep_data_; }
 			const std::vector<double>& surface_styles() const { return surface_styles_; }
+			const std::vector<int>& surface_style_ids() const { return surface_style_ids_; }
 			Serialization(const BRep& brep);
 			virtual ~Serialization() {}
 			const std::string& id() const { return id_; }

src/ifcgeom_schema_agnostic/IfcGeomRenderStyles.h

@@ -90,10 +90,13 @@ namespace IfcGeom {
 		const boost::optional<ColorComponent>& Specular() const { return specular; }
 		const boost::optional<double>& Transparency() const { return transparency; }
 		const boost::optional<double>& Specularity() const { return specularity; }
+		const boost::optional<int>& Id() const { return id; }
+		
 		boost::optional<ColorComponent>& Diffuse() { return diffuse; }
 		boost::optional<ColorComponent>& Specular() { return specular; }
 		boost::optional<double>& Transparency() { return transparency; }
 		boost::optional<double>& Specularity() { return specularity; }
+		boost::optional<int>& Id() { return id; }
 	};
 
 	IFC_GEOM_API const SurfaceStyle* get_default_style(const std::string& ifc_type);

src/ifcopenshell-python/ifcopenshell/geom/occ_utils.py

@@ -41,7 +41,7 @@ except ImportError:
 
     USE_OCCT_HANDLE = True
 
-shape_tuple = namedtuple("shape_tuple", ("data", "geometry", "styles"))
+shape_tuple = namedtuple("shape_tuple", ("data", "geometry", "styles", "style_ids"))
 
 handle, main_loop, add_menu, add_function_to_menu = None, None, None, None
 
@@ -216,16 +216,18 @@ def serialize_shape(shape):
 
 
 def create_shape_from_serialization(brep_object):
-    brep_data, occ_shape, styles = None, None, ()
+    brep_data, occ_shape, styles, style_ids = None, None, (), ()
 
     is_product_shape = True
     try:
         brep_data = brep_object.geometry.brep_data
         styles = brep_object.geometry.surface_styles
+        style_ids = brep_object.geometry.surface_style_ids
     except BaseException:
         try:
             brep_data = brep_object.brep_data
             styles = brep_object.surface_styles
+            style_ids = brep_object.surface_style_ids
             is_product_shape = False
         except BaseException:
             pass
@@ -233,7 +235,7 @@ def create_shape_from_serialization(brep_object):
     styles = tuple(styles[i : i + 4] for i in range(0, len(styles), 4))
 
     if not brep_data:
-        return shape_tuple(brep_object, None, styles)
+        return shape_tuple(brep_object, None, styles, style_ids)
 
     try:
         ss = BRepTools.BRepTools_ShapeSet()
@@ -243,6 +245,6 @@ def create_shape_from_serialization(brep_object):
         pass
 
     if is_product_shape:
-        return shape_tuple(brep_object, occ_shape, styles)
+        return shape_tuple(brep_object, occ_shape, styles, style_ids)
     else:
         return occ_shape

src/ifcwrap/IfcGeomWrapper.i

@@ -269,6 +269,7 @@ struct ShapeRTTI : public boost::static_visitor<PyObject*>
         id = property(id)
         brep_data = property(brep_data)
         surface_styles = property(surface_styles)
+        surface_style_ids = property(surface_style_ids)
 	%}
 };