CGAL users discussion list

[Peter Hachenberger <>]

Hi Bart,

that will be no problem. The code was written for exact geometry and
there are a few assertion, which test for the exact geometry. I see a
good chance that you will succeed with your approach, but we need to
throw out a few assertion. Note, that the same assertions would come up
when you don't use the SNC_indexed_item, but then removing them won't
help you. So, just remove this assertion and also remove others that
come into your way in the class SNC_external_structure.h, but send me a
list of the removed assertions and ask me if you get assertions in other
classes.

Peter

On Sun, 2007-09-02 at 22:33 +0200, Bart Janssens wrote:
> On Friday 31 August 2007 17:12:57 Peter Hachenberger wrote:
> > If this assertion is thrown, the representation of the polyhedron will
> > not be consistent. So catching the assertion means to proceed with an
> > incomplete or faulty representation. Why did you revert back from
> > SNC_indexed_items? They are faster and give you a better chance of
> > succeeding.
> 
> At first, they didn't work at all for me. Then I saw the conversion code 
> needs 
> to initialise the indices, which I copied over to the k3d-to-nef converter. 
> Now it works for simple tests (cubes, spheres with 32x16 faces), but more 
> complicated tests fail with the following assertion violation:
> 
> normalized(cet->circle()) == normalized(ce->circle().opposite()) 
> at /usr/local/include/CGAL/Nef_3/SNC_external_structure.h:1153.
> 
> I have attached the number type I'm using (kernel: 
> CGAL::Cartesian<threshold_number>)
> 
> regards,
> 
> Bart