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- From: "Laurent Rineau (GeometryFactory)" <>
- To:
- Subject: Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror
- Date: Tue, 4 May 2010 14:34:21 +0200
- Organization: GeometryFactory
On Tuesday 04 May 2010 14:16:50 Mariette Yvinec wrote:
> Laurent Rineau (GeometryFactory) wrote:
> > On Monday 03 May 2010 18:43:42 Ramin H wrote:
> >> Hi,
> >> I still don't know everything about C3T3 even though I have read the
> >> documentation. In a 3D triangulation, let's say the cell representing a
> >> facet does not belong to domain (subdomain=0). If we find the mirror
> >> cell of this facet, should it belong to the domain (subdomain > 0) ?
> >>
> >> To test this idea, I wrote the following code:
> >> for(Facet_iterator facet_it = c3t3_.facets_begin() ;
> >>
> >> facet_it != c3t3_.facets_end() ;
> >> ++facet_it)
> >>
> >> {
> >>
> >> Facet facet = *facet_it;
> >> const Facet f = c3t3_.triangulation().mirror_facet(facet);
> >> if( (int)(facet.first->subdomain_index()) ==
> >>
> >> (int)(f.first->subdomain_index()) )
> >>
> >> {
> >>
> >> std::cerr << "Cell and it's mirror have equal subindex: " <<
> >>
> >> (int)(f.first->subdomain_index()) << std::endl;
> >>
> >> }
> >>
> >> }
> >>
> >> Here is some sample output:
> >> Cell and it's mirror have equal subindex: 1
> >> Cell and it's mirror have equal subindex: 1
> >> Cell and it's mirror have equal subindex: 0
> >> Cell and it's mirror have equal subindex: 1
> >> Cell and it's mirror have equal subindex: 1
> >> Cell and it's mirror have equal subindex: 1
> >> Cell and it's mirror have equal subindex: 0
> >> Cell and it's mirror have equal subindex: 1
> >>
> >> Is this correct behavior? If Facet_iterator is iterating over the facets
> >> on the surface, why a cell representing that facet and it's mirror both
> >> can have subdomain index equal to 1 or 0?
> >
> > No it is not a correct behavior. There is an inconsistency between the
> > answers
> >
> > provided by the mesh domain oracle to the two following questions :
> > - does a given segment/ray intersects the boundary of the domain,
> > - is a given center of cell in the domain or not.
> >
> > Does your domain class (CGAL::Polyhedral_mesh_domain_3 or something like
> > that) use a filtered (exact) kernel or an inexact one?
>
> Also what happens if the input polyhedral surface include twice the same
> triangle?
In that case you are right the polyhedral oracle will also produce an
incorrect result.
But I have checked the data file of Ramin before writing my answer.
--
Laurent Rineau, PhD
R&D Engineer at GeometryFactory http://www.geometryfactory.com/
Release Manager of the CGAL Project http://www.cgal.org/
- [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/03/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Laurent Rineau (GeometryFactory), 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Mariette Yvinec, 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Laurent Rineau (GeometryFactory), 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/05/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/05/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Mariette Yvinec, 05/06/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Stephane Tayeb, 05/06/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/06/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/05/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/05/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Ramin H, 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Mariette Yvinec, 05/04/2010
- Re: [cgal-discuss] 3D meshing - Subdomain index of a cell and it's mirror, Laurent Rineau (GeometryFactory), 05/04/2010
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