CGAL users discussion list

[Peter Hachenberger <>]

Hi, 

How do you extract the vertices from a triangle? I'm not completely sure
how our triangulation works, but I would assume that the vertices of a
facet should be oriented consistently if you triangulate an orientable
surface.

Peter


On Tue, 2007-07-17 at 20:54 +0200, Thomas Zangl - Home wrote:
>  Am Tue, 17 Jul 2007 20:28:10 +0200 (CEST), schrieb 
> <>:
> 
> Hi!
> 
> >> (Is there some automatism which can do this automatically?
> >> What is the best practice to fix those triangles?)
> >
> >Usually, you do not extract these triangles from your 3D triangulation
> >randomly: you extract a triangle as the neighbor of an already extracted
> >triangle. You just have to check that you give the newly extracted
> >triangle the same orientation as its predecessor.
> 
> In my case, this must not be true. I iterate over a triangulation
> using a the facet iterator. If a facet fullfills a criterion I add it
> to my list of points and facets and later they get inserted into a
> Polyhedron. As you can see, it is possible to happen, that there are
> faces which are not of the same orientation. What can I do? Fixing
> every face is going to be an intensive task which I want to avoid
> if possible.
> 
> Best regards,
> -- 
> ----------------------------------------------------------------
> ,yours Thomas Zangl, Bakk.rer.soc.oec. - 
> 
>  -
> - Freelancer - IT Consulting & Software Development -
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