CGAL users discussion list

[Laure Guicherd <>]

Hi everyone,
Is there someone on this ? Because I am meeting the exact same issue. 
Everything else is working nicely, but sometimes it fails this way, and 
i have absolutely no idea of the reason for this :(
My meshes are closed and valid, with no self-intersections or "flat" faces.

Any idea will be helpful, thank you very much !

Laure Guicherd

Chris Hamilton wrote:
> Previously, I've used the GNU triangulated surface library (libgts), but
> I've been having precision issues with that, and am now trying to work
> with CGAL.  I'm trying to compute the intersection between two closed
> and bounded polyhedra.
>
> I'm using Nef_polyhedron_3 with the
> Exact_predicates_exact_constructions_kernel.  The polyhedra are being
> laoded as .off files through the Polyhedron_3 object, converted to
> Nef_polyhedron_3 objects, and the intersection computed.  Afterwards,
> the result is converted back to a Polyhedron_3, and output as an .off file.
>
> All is largely well, except sometimes the process fails with the
> following message:
>
>  sorry, this triangulation does not deal with
>  intersecting constraints
>
> This error occurs during conversion back to Polyhedron_3.  What exactly
> does this error mean?  Is there a way I can get the results out as an
> .off file?
>
> And on a slightly related question: is there a way to compute the 3d
> volume of a closed polyhedron in CGAL?  Either via the Nef_polyhedron_3
> data-structure, or the Polyhedron_3, as I'd always be dealing with
> closed meshes.
>
> Regards,
>
> Chris
>
>