Edge Polygon Mesh

Hi everybody!

I want to write my own visualization routines. I meshed my shape via
BRepMesh_IncrementalMesh::BRepMesh_IncrementalMesh () and can access the surface triangulation through BRep_Tool::Triangulation. So i can draw the faces. But in order to draw the edges, i need to access the edge polygonialization. I tried it with BRep_Tool::Polygon3D, but it always returns a NULL handle.
How can I access the polygons describing the edges?
Or do I have to call any function to mesh the edges first (I thought it should be done by IncrementalMesh)?

Thank you,
Robert

Rob Bachrach's picture

I do this by first getting the triangulation on one of the faces attached to the edge using BRep_Tool::Triangulation. Then, I get the triangulation on the edge using BRep_Tool::PolygonOnTriangulation. You can create a map of edges to faces containing those edges using TopExp::MapShapesAndAncestors.

robert_gaisbauer's picture

thank you for your answer. i have tried it that way now. finally, it works!