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[Monique Teillaud <>]

Hi

that test does the following:

for each finite cell c
  for each adjacent cell n of c
    is the 4th vertex of n outside the circumscribing sphere of c?

see
http://doc.cgal.org/latest/Triangulation_3/classCGAL_1_1Delaunay__triangulation__3.html#af5c0c915316ad748b7c04ff5a9184dfe
and
http://doc.cgal.org/latest/Triangulation_3/index.html#title0

--
Monique Teillaud
http://www.inria.fr/sophia/members/Monique.Teillaud/
INRIA Sophia Antipolis - Méditerranée
Institut National de Recherche en Informatique et Automatique

Le 28/03/14 23:03, gupta61 a écrit :
> One more thing. So the place where the code is failing is
>
> (Taken from Delaunay_triangulation_3.h, CGAL 4.1)
> ////////////////////////////////////////////////////////////////////////////////////
>    if ( ! Tr_Base::is_valid(c,verbose,level) ) {
>      if (verbose) {
>        std::cerr << "combinatorically invalid cell" ;
>        for (int i=0; i <= dimension(); i++ )
>         std::cerr << c->vertex(i)->point() << ", " ;
>        std::cerr << std::endl;
>      }
>      CGAL_triangulation_assertion(false);
>      return false;
>    }
>    switch ( dimension() ) {
>    case 3:
>      {
>        if ( ! is_infinite(c) ) {
>         is_valid_finite(c,verbose,level);
>         for (int i=0; i<4; i++ ) {
>           if (side_of_sphere(c, 
> c->vertex((c->neighbor(i))->index(c))->point())
>               == ON_BOUNDED_SIDE ) {
>             if (verbose)
>                 std::cerr << "non-empty sphere " << std::endl;
>             CGAL_triangulation_assertion(false);
>             return false;
>           }
>         }
>        }
>        break;
>      }
> //////////////////////////////////////////////////////////////////////////////////////////////
>
> Now the triangulation is valid because it is checking that
> "Tr_Base::is_valid(c,verbose,level)" through this call. It is the second
> test which I don't understand in terms of what it is trying to check? Can
> you let me know a little bit more details about what /property/ is it
> checking by this call "side_of_sphere(c,
> c->vertex((c->neighbor(i))->index(c))->point()) == ON_BOUNDED_SIDE" ?
>
> Thanks.
>
>
>
> -----
> Piyush Gupta
> UIUC
> --
> View this message in context: 
> http://cgal-discuss.949826.n4.nabble.com/Assertion-violation-in-Delaunay-triangulation-3-h-tp4659027p4659031.html
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