geomodel_builder_from_mesh.cpp

Go to the documentation of this file.

/*
 * Copyright (c) 2012-2017, Association Scientifique pour la Geologie et ses
 * Applications (ASGA). All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of ASGA nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ASGA BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *     http://www.ring-team.org
 *
 *     RING Project
 *     Ecole Nationale Superieure de Geologie - GeoRessources
 *     2 Rue du Doyen Marcel Roubault - TSA 70605
 *     54518 VANDOEUVRE-LES-NANCY
 *     FRANCE
 */

#include <ringmesh/geomodel/geomodel_builder_from_mesh.h>

#include <stack>

#include <geogram/mesh/mesh.h>

namespace RINGMesh
{
    void GeoModelBuilderSurfaceMesh::
        build_polygonal_surfaces_from_connected_components()
    {
        std::vector< index_t > global_vertex_id_to_id_in_cc(
            mesh_.vertices.nb(), NO_ID );

        std::vector< bool > visited( mesh_.facets.nb(), false );
        for( auto i : range( mesh_.facets.nb() ) )
        {
            if( !visited[i] )
            {
                std::vector< index_t > cc_corners;
                std::vector< index_t > cc_facets_ptr;
                std::vector< vec3 > cc_vertices;

                std::fill( global_vertex_id_to_id_in_cc.begin(),
                    global_vertex_id_to_id_in_cc.end(), NO_ID );

                // First facet begin at corner 0
                cc_facets_ptr.push_back( 0 );

                // Propagate from facet #i
                std::stack< index_t > S;
                S.push( i );
                while( !S.empty() )
                {
                    index_t f{ S.top() };
                    S.pop();
                    visited[f] = true;

                    for( auto c : range( mesh_.facets.corners_begin( f ),
                             mesh_.facets.corners_end( f ) ) )
                    {
                        index_t v{ mesh_.facet_corners.vertex( c ) };
                        if( global_vertex_id_to_id_in_cc[v] == NO_ID )
                        {
                            index_t index{ static_cast< index_t >(
                                cc_vertices.size() ) };
                            global_vertex_id_to_id_in_cc[v] = index;
                            cc_vertices.push_back( mesh_.vertices.point( v ) );
                        }
                        cc_corners.push_back( global_vertex_id_to_id_in_cc[v] );

                        index_t n{ mesh_.facet_corners.adjacent_facet( c ) };
                        if( n != NO_ID && !visited[n] )
                        {
                            visited[n] = true;
                            S.push( n );
                        }
                    }
                    index_t nb_cc_corners{ static_cast< index_t >(
                        cc_corners.size() ) };
                    cc_facets_ptr.push_back( nb_cc_corners );
                }

                gmme_id surface_gme{ topology.create_mesh_entity(
                    Surface3D::type_name_static() ) };
                geometry.set_surface_geometry( surface_gme.index(), cc_vertices,
                    cc_corners, cc_facets_ptr );
            }
        }
    }

} // namespace RINGMesh