How to turn a Surface Mesh into a Polyhedron?

Question

I have defined and loaded a surface mesh as suggested in here: typedef OpenMesh::PolyMesh_ArrayKernelT</* MyTraits*/> Surface_mesh;, yet to use such algorithm as Triangulated Surface Mesh Segmentation I need a Polyhedron alike:

typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
typedef CGAL::Polyhedron_3<Kernel> Polyhedron;

Yet I do not see how to turn one into another. How to do such thing in CGAL?

A simplified demo:

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/mesh_segmentation.h>
#include <CGAL/Polygon_mesh_processing/connected_components.h>
#include <CGAL/boost/graph/copy_face_graph.h>
#include <OpenMesh/Core/Mesh/PolyMesh_ArrayKernelT.hh>
#include <OpenMesh/Core/IO/MeshIO.hh>
#include <iostream>

typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
typedef CGAL::Polyhedron_3<Kernel> Polyhedron;
typedef OpenMesh::PolyMesh_ArrayKernelT</* MyTraits*/> Surface_mesh;

int main()
{
    // create and read Polyhedron
    Surface_mesh mesh_in, mesh_out;
    Polyhedron mesh;
    OpenMesh::IO::read_mesh( mesh_in, "data/elephant.off");
    CGAL::copy_face_graph(mesh_in, mesh);

    CGAL::copy_face_graph(mesh, mesh_out);
    if (!OpenMesh::IO::write_mesh(mesh_out, "slon.obj"))
    {
        std::cerr << "write error\n";
        exit(1);
    }
}

Which fails to compile due to

boost_1_63_0\boost/graph/graph_traits.hpp(57): error C2039: vertex_descriptor: is not a member of "OpenMesh::PolyMesh_ArrayKernelT< OpenMesh::DefaultTraits >"

sloriot sloriot · Accepted Answer · 2017-04-23T12:19:24

The algorithm is working directly with this OpenMesh data structure, there is no need to do a copy. However, if you happen to need to copy data structures, you can use the fonction CGAL::copy_face_graph().

How to turn a Surface Mesh into a Polyhedron?

1 Answers