Method extract_boundary

tools/MeshUtils/BoundaryEdges.cpp:45–78

}

void BoundaryEdges::extract_boundary(const Mesh& mesh) {
    typedef Duplet Edge;
    typedef DupletMap<size_t> EdgeFaceMap;
    EdgeFaceMap edge_face_map;

    const size_t num_vertex_per_face = mesh.get_vertex_per_face();
    const size_t num_faces = mesh.get_num_faces();

    for (size_t i=0; i<num_faces; i++) {
        const VectorI face = mesh.get_face(i);
        for (size_t j=0; j<num_vertex_per_face; j++) {
            auto v0 = face[j];
            auto v1 = face[(j+1) % num_vertex_per_face];
            edge_face_map.insert({v0, v1}, i);
        }
    }

    std::vector<size_t> boundaries;
    std::vector<size_t> boundary_faces;
    for (EdgeFaceMap::const_iterator itr=edge_face_map.begin();
            itr != edge_face_map.end(); itr++) {
        if (itr->second.size() == 1) {
            boundaries.push_back(itr->first.get_ori_data()[0]);
            boundaries.push_back(itr->first.get_ori_data()[1]);
            boundary_faces.push_back(itr->second[0]);
        }
    }

    m_boundaries.resize(boundaries.size() / 2, 2);
    std::copy(boundaries.begin(), boundaries.end(), m_boundaries.data());
    m_boundary_faces.resize(boundary_faces.size());
    std::copy(boundary_faces.begin(), boundary_faces.end(),
            m_boundary_faces.data());
}

void BoundaryEdges::extract_boundary_nodes() {
    size_t num_entries = m_boundaries.rows() * m_boundaries.cols();