diff options
Diffstat (limited to 'src/Alpha_complex/include/gudhi/Alpha_complex.h')
-rw-r--r-- | src/Alpha_complex/include/gudhi/Alpha_complex.h | 82 |
1 files changed, 46 insertions, 36 deletions
diff --git a/src/Alpha_complex/include/gudhi/Alpha_complex.h b/src/Alpha_complex/include/gudhi/Alpha_complex.h index 1ce6267d..9d5a9bad 100644 --- a/src/Alpha_complex/include/gudhi/Alpha_complex.h +++ b/src/Alpha_complex/include/gudhi/Alpha_complex.h @@ -171,35 +171,58 @@ class Alpha_complex { return vertex_handle_to_iterator_.at(vertex)->point(); } + /** \brief number_of_vertices returns the number of vertices (same as the number of points). + * + * @return The number of vertices. + */ + const std::size_t number_of_vertices() const { + return vertex_handle_to_iterator_.size(); + } + private: template<typename InputPointRange > void init_from_range(const InputPointRange& points) { auto first = std::begin(points); auto last = std::end(points); - // point_dimension function initialization - Point_Dimension point_dimension = kernel_.point_dimension_d_object(); - - // Delaunay triangulation is point dimension. - triangulation_ = new Delaunay_triangulation(point_dimension(*first)); - - std::vector<Point_d> point_cloud(first, last); - // Creates a vector {0, 1, ..., N-1} - std::vector<std::ptrdiff_t> indices(boost::counting_iterator<std::ptrdiff_t>(0), - boost::counting_iterator<std::ptrdiff_t>(point_cloud.size())); - - typedef boost::iterator_property_map<typename std::vector<Point_d>::iterator, - CGAL::Identity_property_map<std::ptrdiff_t>> Point_property_map; - typedef CGAL::Spatial_sort_traits_adapter_d<Kernel, Point_property_map> Search_traits_d; - - CGAL::spatial_sort(indices.begin(), indices.end(), Search_traits_d(std::begin(point_cloud))); - - typename Delaunay_triangulation::Full_cell_handle hint; - for (auto index : indices) { - typename Delaunay_triangulation::Vertex_handle pos = triangulation_->insert(point_cloud[index], hint); - // Save index value as data to retrieve it after insertion - pos->data() = index; - hint = pos->full_cell(); + if (first != last) { + // point_dimension function initialization + Point_Dimension point_dimension = kernel_.point_dimension_d_object(); + + // Delaunay triangulation is point dimension. + triangulation_ = new Delaunay_triangulation(point_dimension(*first)); + + std::vector<Point_d> point_cloud(first, last); + + // Creates a vector {0, 1, ..., N-1} + std::vector<std::ptrdiff_t> indices(boost::counting_iterator<std::ptrdiff_t>(0), + boost::counting_iterator<std::ptrdiff_t>(point_cloud.size())); + + typedef boost::iterator_property_map<typename std::vector<Point_d>::iterator, + CGAL::Identity_property_map<std::ptrdiff_t>> Point_property_map; + typedef CGAL::Spatial_sort_traits_adapter_d<Kernel, Point_property_map> Search_traits_d; + + CGAL::spatial_sort(indices.begin(), indices.end(), Search_traits_d(std::begin(point_cloud))); + + typename Delaunay_triangulation::Full_cell_handle hint; + for (auto index : indices) { + typename Delaunay_triangulation::Vertex_handle pos = triangulation_->insert(point_cloud[index], hint); + // Save index value as data to retrieve it after insertion + pos->data() = index; + hint = pos->full_cell(); + } + // -------------------------------------------------------------------------------------------- + // double map to retrieve simplex tree vertex handles from CGAL vertex iterator and vice versa + // Loop on triangulation vertices list + for (CGAL_vertex_iterator vit = triangulation_->vertices_begin(); vit != triangulation_->vertices_end(); ++vit) { + if (!triangulation_->is_infinite(*vit)) { +#ifdef DEBUG_TRACES + std::cout << "Vertex insertion - " << vit->data() << " -> " << vit->point() << std::endl; +#endif // DEBUG_TRACES + vertex_handle_to_iterator_.emplace(vit->data(), vit); + } + } + // -------------------------------------------------------------------------------------------- } } @@ -248,19 +271,6 @@ class Alpha_complex { complex.set_dimension(triangulation_->maximal_dimension()); // -------------------------------------------------------------------------------------------- - // double map to retrieve simplex tree vertex handles from CGAL vertex iterator and vice versa - // Loop on triangulation vertices list - for (CGAL_vertex_iterator vit = triangulation_->vertices_begin(); vit != triangulation_->vertices_end(); ++vit) { - if (!triangulation_->is_infinite(*vit)) { -#ifdef DEBUG_TRACES - std::cout << "Vertex insertion - " << vit->data() << " -> " << vit->point() << std::endl; -#endif // DEBUG_TRACES - vertex_handle_to_iterator_.emplace(vit->data(), vit); - } - } - // -------------------------------------------------------------------------------------------- - - // -------------------------------------------------------------------------------------------- // Simplex_tree construction from loop on triangulation finite full cells list if (triangulation_->number_of_vertices() > 0) { for (auto cit = triangulation_->finite_full_cells_begin(); cit != triangulation_->finite_full_cells_end(); ++cit) { |