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["Sebastien Loriot (GeometryFactory)" <>]

The code looks OK.
Do you call delegate several times on the same polyhedron?
Having an example I can compile and run would be nice as I have no other 
idea for now.

Sebastien.

On 03/06/2013 06:43 AM, Evan Behar wrote:
> I am loading the model from an OBJ file--first I read in the vertices
> and facets from the OBJ file and then I am constructing the polyhedron
> using those values. I add the vertices all at once and then construct
> the facets using the vertex indices, so I am almost certainly reusing
> the vertices. The modifier code is below:
>
> class Build_polyhedron : public
> CGAL::Modifier_base<Polyhedron::HalfedgeDS> {
>    public:
>      Build_polyhedron() {}
>      void operator()(Polyhedron::HalfedgeDS& hds) {
>        CGAL::Polyhedron_incremental_builder_3<Polyhedron::HalfedgeDS>
> builder(hds,true);
>        const std::vector<Point>& vertices = OBJReader::vertices;
>        const std::vector<std::vector<int> >& facets = OBJReader::facets;
>
>        builder.begin_surface(vertices.size(),facets.size());
>
>        // add vertices
>        for (int i=0;i<vertices.size();i++) {
>          builder.add_vertex(vertices[i]);
>        }
>
>        // add facets
>        for (int i=0;i<facets.size();i++) {
>          builder.begin_facet();
>
>          for (int j=0;j<facets[i].size();j++) {
>            builder.add_vertex_to_facet(facets[i][j]);
>          }
>
>          Halfedge_handle h = builder.end_facet();
>          std::cout << "Validating...\n";
>          if (h->opposite()->facet() != Facet_handle()) {
>            std::cout << "Opposite halfedge's facet not invalid!\n";
>          }
>        }
>
>        builder.end_surface();
>      }
> };
>
>
>
> On Wed, Mar 6, 2013 at 12:37 AM, Sebastien Loriot (GeometryFactory)
> <
>  
> <mailto:>>
>  wrote:
>
>     Can you give more information like the modifier you wrote for example?
>
>     A common mistake is not reusing the vertices. If you add two vertices
>     with the same coordinates, they will be consider as different.
>
>     Sebastien.
>
>     On 03/06/2013 05:51 AM, Evan Behar wrote:
>
>         I have constructed a Polyhedron_3, /P/, using the
>
>         Polyhedron_incremental___builder_3, and I am running into the
>         problem that
>         none of the halfedges in the structure are being associated with any
>         opposite halfedges that have been previously constructed.
>
>         After construction, retrieving a Halfedge_handle /h/ from /P /and
>         calling /h->opposite()->facet()/ always results in an invalid
>         Facet_handle.
>
>
>         Is this expected behavior from
>         Polyhedron_incremental___builder_3? Do I
>         have to stitch the facets together manually?
>
>
>
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