CGAL users discussion list

[Andre Schmeisser <>]

On 09/27/2013 07:20 AM, Sebastien Loriot (GeometryFactory) wrote:
> In the non-triangulated version, your polyhedron has some facets with
> its points not being exactly in a plane. Nef does not like that.

Yes, that's what I guessed might be the problem. Hence trying to
triangulate the polyhedron faces by simply adding some diagonals.

> In the triangulated version, your polyhedron has some self-intersections
> which I suspect to be the reason why Nef is not happy.

I did not realize the polyhedron is degenerated. I will have to further
investigate how I could come up with this degenerate polyhedron in the
first place.

> 
> The following is working:
> 
>     istringstream off(polyhedronOffStr);
> 
>     Nef_polyhedron NP;
>     CGAL::OFF_to_nef_3(off, NP);


Thanks, this works.
Is there a way to directly construct the Nef polyhedron without first
serializing to/from an OFF string? (My data is not in OFF format,
I just used the output operator of Polyhedron_3 for this to create
example data).

Best regards,
Andre

-- 
Dipl.-Inf. Andre Schmeißer
Department of Transport Processes
Fraunhofer Institute for Industrial Mathematics ITWM
Fraunhofer-Platz 1, D-67663 Kaiserslautern
Internet: www.itwm.fraunhofer.de