polyhedron_builder_from_projected_triangulation.h

// Copyright (c) 2018 Coronis Computing S.L. (Spain)
// All rights reserved.
//
// This file is part of EMODnet Quantized Mesh Generator for Cesium.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
//
// Author: Ricard Campos (ricardcd@gmail.com)

#ifndef EMODNET_QMGC_POLYHEDRON_BUILDER_FROM_PROJECTED_TRIANGULATION_H
#define EMODNET_QMGC_POLYHEDRON_BUILDER_FROM_PROJECTED_TRIANGULATION_H

template<class ProjectedTriangulation2, class HDS>
class PolyhedronBuilderFromProjectedTriangulation : public CGAL::Modifier_base<HDS> {
public:
    typedef ProjectedTriangulation2 Tri;

    Tri m_dt ;

    PolyhedronBuilderFromProjectedTriangulation( const Tri &dt ) : m_dt(dt) {}

    void operator()( HDS& hds ) {
        typedef typename HDS::Vertex   Vertex;
        typedef typename Vertex::Point Point;

        // Polyhedron_3 incremental builder
        CGAL::Polyhedron_incremental_builder_3<HDS> B( hds, true);
        B.begin_surface( m_dt.number_of_vertices(), m_dt.number_of_faces() );

        std::map<typename Tri::Vertex_handle,int> indices;
        int counter = 0 ;
        for(typename Tri::Finite_vertices_iterator it = m_dt.finite_vertices_begin();
            it != m_dt.finite_vertices_end(); ++it)
        {
            B.add_vertex( it->point() );
            indices.insert(std::pair<typename Tri::Vertex_handle,int>(it, counter++));
        }

        for(typename Tri::Finite_faces_iterator it = m_dt.finite_faces_begin();
            it != m_dt.finite_faces_end(); ++it)
        {
            B.begin_facet();
            B.add_vertex_to_facet( indices[it->vertex(0)] );
            B.add_vertex_to_facet( indices[it->vertex(1)] );
            B.add_vertex_to_facet( indices[it->vertex(2)] );
            B.end_facet();
        }

        // End the surface
        B.end_surface();
    }
};


#endif //EMODNET_QMGC_POLYHEDRON_BUILDER_FROM_PROJECTED_TRIANGULATION_H