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[Iason Manolas <>]

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 <> 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.

Find the code reproducing the problem here 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) <> 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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