STEP models tessellating performance

Hello everyone,

I am trying to implement a STEP format reader for a 3D viewer and am experiencing some performance issues when tessellating TopoDS_Shapes. I was searching this forum for some hints to improve performance but can't find any. I was following a straight-froward approach to tessellation (code example is attached bellow) but it seems to me that some pre-processing have to be done to shapes to reach better performance. I was comparing STEP loading performance of my application with CAD Assistant (powered by OCCT v7.1.1.dev) an I have, in average, 50% slower results that CAD Assistant. Have to mention that I'm using OCCT v7.2.0.

Here is my tessellation code:

bool
OCCProxy::tessellateShapes(std::list<TopoDS_Shape> & shapes) {

	for (auto & shape : shapes) {

		BRepMesh_IncrementalMesh incMesh(shape, 1, false, 1);

        // This method collects all TopoDS_Face instances of current shape with help of
        // TopExp_Explorer
		std::list<TopoDS_Face> faces = collectFaces(shape);

		for (auto& face : faces) {
			// Collects tessellated data and populates mesh parameter.
			processFace(face);
		}

		faces.clear();

		_meshes.push_back(mesh);
	}

	return true;
}

bool
OCCProxy::processFace(TopoDS_Face& face) {

	// Use default location for the face.
	TopLoc_Location location = TopLoc_Location(gp_Trsf::gp_Trsf());
	// Get triangulation instance that contains all triangulation-related information.
	const opencascade::handle<Poly_Triangulation> triangulation = BRep_Tool::Triangulation(face, location);


	Poly_Array1OfTriangle occtpTriangles = triangulation.get()->Triangles();

	const TColgp_Array1OfPnt nodes = triangulation.get()->Nodes();

    //**************************
    Process collected nodes and triangles to get mesh information
    //**************************

	return true;
}

Thank you for help in advance,

Vlad