I'd like to suggest to refactor the XSDRAWSTLVRML_DataSource to be included in either the STLMesh or MeshVS toolkit, for the following reasons:
1) the STLMesh converts a triangular mesh to nurbs facets, which is a really poor idea: its an incredible overhead and incurs massive overhead. Worst of all, this odd behaviour is not documented at all.
2) hence using MeshVS is a more logical approach to working with STL's; simple draw them in the viewer
3) the reason why XSDRAWSTLVRML_DataSource is *so* bothersome is that the XSDRAWSTLVRML part of the drawing mechanism of the TCL/TK interpreter. _NOT___ a logical place to look for such an important class!
Can I kindly suggest to untangle this incredible mess and to make it part of the STLMesh (MeshVS, fine)?
Its just sad to see an important piece of functionality orphaned like this in one of the dusty corners of OCC.