BGL_polyhedron_3/copy_polyhedron.cpp

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Exact_predicates_exact_constructions_kernel.h>

#include <CGAL/Polyhedron_3.h>
#include <CGAL/Surface_mesh.h>

#if defined(CGAL_USE_OPENMESH)
#include <OpenMesh/Core/IO/MeshIO.hh>
#include <OpenMesh/Core/Mesh/PolyMesh_ArrayKernelT.hh>
#include <CGAL/boost/graph/graph_traits_PolyMesh_ArrayKernelT.h>
#endif

#include <CGAL/boost/graph/copy_face_graph.h>

#include <iostream>
#include <fstream>
#include <iterator>

#include <unordered_map>


typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;

typedef CGAL::Polyhedron_3<Kernel>                       Source;
typedef boost::graph_traits<Source>::vertex_descriptor   sm_vertex_descriptor;
typedef boost::graph_traits<Source>::halfedge_descriptor sm_halfedge_descriptor;
typedef boost::graph_traits<Source>::face_descriptor     sm_face_descriptor;

typedef CGAL::Exact_predicates_exact_constructions_kernel Other_kernel;
typedef Other_kernel::Point_3                             Point;

int main(int argc, char* argv[])
{
  Source S;

  std::ifstream in((argc>1)?argv[1]:CGAL::data_file_path("meshes/cube_poly.off"));
  in >> S;
  assert( CGAL::is_valid_polygon_mesh(S) );

  // Note that the vertex_point property of the Source and Target1
  // come from different kernels.
  typedef CGAL::Surface_mesh<Point> Target1;
  Target1 T1;
  CGAL::copy_face_graph(S, T1);
  assert( CGAL::is_valid_polygon_mesh(T1) );
  assert( vertices(S).size()==vertices(T1).size() );
  assert( halfedges(S).size()==halfedges(T1).size() );
  assert( faces(S).size()==faces(T1).size() );

#if defined(CGAL_USE_OPENMESH)
  typedef OpenMesh::PolyMesh_ArrayKernelT</* MyTraits*/> Target2;
  Target2 T2;
  {
    typedef boost::graph_traits<Target2>::vertex_descriptor   tm_vertex_descriptor;
    typedef boost::graph_traits<Target2>::halfedge_descriptor tm_halfedge_descriptor;
    typedef boost::graph_traits<Target2>::face_descriptor     tm_face_descriptor;

    // Use an unordered_map to keep track of elements.
    std::unordered_map<sm_vertex_descriptor, tm_vertex_descriptor>     v2v;
    std::unordered_map<sm_halfedge_descriptor, tm_halfedge_descriptor> h2h;
    std::unordered_map<sm_face_descriptor, tm_face_descriptor>         f2f;

    CGAL::copy_face_graph(S, T2, CGAL::parameters::vertex_to_vertex_output_iterator(std::inserter(v2v, v2v.end()))
                                 .halfedge_to_halfedge_output_iterator(std::inserter(h2h, h2h.end()))
                                 .face_to_face_output_iterator(std::inserter(f2f, f2f.end())));
    assert( CGAL::is_valid_polygon_mesh(T2) );
    assert( v2v.size()==vertices(T2).size() );
    assert( h2h.size()==halfedges(T2).size() );
    assert( f2f.size()==faces(T2).size() );
    assert( vertices(S).size()==vertices(T2).size() );
    assert( halfedges(S).size()==halfedges(T2).size() );
    assert( faces(S).size()==faces(T2).size() );
  }
#endif
  S.clear();
  {
    typedef boost::graph_traits<Target1>::vertex_descriptor   source_vertex_descriptor;
    typedef boost::graph_traits<Target1>::halfedge_descriptor source_halfedge_descriptor;
    typedef boost::graph_traits<Target1>::face_descriptor source_face_descriptor;

    typedef boost::graph_traits<Source>::vertex_descriptor   tm_vertex_descriptor;
    typedef boost::graph_traits<Source>::halfedge_descriptor tm_halfedge_descriptor;
    typedef boost::graph_traits<Source>::face_descriptor   tm_face_descriptor;


    std::unordered_map<source_vertex_descriptor, tm_vertex_descriptor> v2v;
    std::unordered_map<source_halfedge_descriptor, tm_halfedge_descriptor> h2h;
    std::unordered_map<source_face_descriptor, tm_face_descriptor> f2f;
    CGAL::copy_face_graph(T1, S, CGAL::parameters::vertex_to_vertex_map(boost::make_assoc_property_map(v2v))
                          .halfedge_to_halfedge_output_iterator(std::inserter(h2h, h2h.end()))
                          .face_to_face_map(boost::make_assoc_property_map(f2f)));

    assert( CGAL::is_valid_polygon_mesh(S) );
    assert( vertices(S).size()==vertices(T1).size() );
    assert( halfedges(S).size()==halfedges(T1).size() );
    assert( faces(S).size()==faces(T1).size() );
  }
  return 0;
}