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["Sebastien Loriot (GeometryFactory)" <>]

Try is_polygon_soup_a_polygon_mesh().

http://doc.cgal.org/latest/Polygon_mesh_processing/group__PMP__repairing__grp.html#ga8b9d12d817b5cc76f5a42d74eac75bf3

Sebastien.


On 12/02/2016 12:25 PM, Iason Manolas wrote:
> I used the cactus.off as in the example of mesh segmentation and I get
> that the number of segments is 3 which sounds right.. So something must
> be wrong with my polyhedron. I use the following code to build it from a
> vector of vertices and a vector of indices:
>
> void buildPolyhedron()
>     {
>         P.clear();
>         std::cout<<"Building Polyhedron.."<<std::endl;
>        std::vector<Kernel::Point_3> points;
>        std::vector<std::vector<std::size_t>> polygons;
>
>        for(auto const& vert:vertices)
>        {
>
> points.push_back(Kernel::Point_3(vert.Position.x,vert.Position.y,vert.Position.z));
>
>        }
>        for(int i=0;i<indices.size();i+=3)
>        {
>        std::vector<std::size_t> tri{indices[i],indices[i+1],indices[i+2]};
>        polygons.push_back(tri);
>        }
>        CGAL::Polygon_mesh_processing::orient_polygon_soup(points,polygons);
>
> CGAL::Polygon_mesh_processing::polygon_soup_to_polygon_mesh(points,polygons,P);
>        if (CGAL::is_closed(P) &&
> (!CGAL::Polygon_mesh_processing::is_outward_oriented(P)))
>          CGAL::Polygon_mesh_processing::reverse_face_orientations(P);
>
> CGAL::Polygon_mesh_processing::compute_vertex_normals(P,boost::make_assoc_property_map(normalsMap));
>         std::cout<<"Finished building Polyhedron."<<std::endl;
>     }
> Could it be that
> CGAL::Polygon_mesh_processing::polygon_soup_to_polygon_mesh constructs
> an "inappropriate" Polyhedron for CGAL::segmentation_via_sdf_values?
>
> On 21 November 2016 at 13:10, Iason Manolas 
> <
> <mailto:>>
>  wrote:
>
>     Unfortunately since my code deals with 3d models there are some
>     dependencies and the code is not that small. I tried to make it as
>     short as possible though.
>
>     Except cgal,gmp,boost I use assimp.
>     <http://www.assimp.org/>
>     Find the code reproducing the problem here
>     <https://github.com/IasonManolas/CGAL_meshSegm_problem> and please
>     don't hesitate to write back if you think I neglected something.
>
>     Regards,
>     Iason
>
>
>     On 21 November 2016 at 10:45, Sebastien Loriot (GeometryFactory)
>     
> <
>  
> <mailto:>>
>  wrote:
>
>         Could you share a minimal example that we can run and that would
>         show the pb?
>
>         Thanks,
>
>         Sebastien.
>
>
>
>         On 11/18/2016 12:41 PM, Iason Manolas wrote:
>
>             Hello ,
>
>             I am trying to segment a polyhedron using the following code:
>
>              void meshSegmentation()
>                 {
>                     std::cout<<"Segmenting Mesh.."<<std::endl;
>                     using
>             
> Facet_int_map=std::map<CGALPolyhedron::Facet_const_handle,std::size_t>;
>                     Facet_int_map internal_segment_map;
>                     boost::associative_property_map<Facet_int_map>
>             segment_property_map(internal_segment_map);
>                     std::size_t
>             
> number_of_segments=CGAL::segmentation_via_sdf_values(P,segment_property_map);
>                     std::cout<<"Number of segments:
>             "<<number_of_segments<<std::endl;
>                     std::cout<<"Segmentation finished."<<std::endl;
>
>                 }
>
>             (I have previously checked that the P.is_valid()==1)
>             Why is the number of segments always equal to the number of
>             faces?
>
>
>
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