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Diffstat (limited to 'src/common/include/gudhi/Delaunay_triangulation_off_io.h')
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1 files changed, 308 insertions, 0 deletions
diff --git a/src/common/include/gudhi/Delaunay_triangulation_off_io.h b/src/common/include/gudhi/Delaunay_triangulation_off_io.h new file mode 100644 index 00000000..de5fa2af --- /dev/null +++ b/src/common/include/gudhi/Delaunay_triangulation_off_io.h @@ -0,0 +1,308 @@ +/* This file is part of the Gudhi Library. The Gudhi library + * (Geometric Understanding in Higher Dimensions) is a generic C++ + * library for computational topology. + * + * Author(s): Vincent Rouvreau + * + * Copyright (C) 2015 INRIA Saclay (France) + * + * 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 <http://www.gnu.org/licenses/>. + */ +#ifndef SRC_ALPHA_SHAPES_INCLUDE_GUDHI_ALPHA_SHAPES_DELAUNAY_TRIANGULATION_OFF_IO_H_ +#define SRC_ALPHA_SHAPES_INCLUDE_GUDHI_ALPHA_SHAPES_DELAUNAY_TRIANGULATION_OFF_IO_H_ + +#include <string> +#include <vector> +#include <fstream> +#include <map> + +#include "gudhi/Off_reader.h" + +namespace Gudhi { + +/** \brief OFF file visitor implementation according to Off_reader in order to construct a CGAL Delaunay triangulation. + * + * For more informations on CGAL Delaunay triangulation, please refer to the corresponding chapter in page + * http://doc.cgal.org/latest/Triangulation/ + */ +template<typename Complex> +class Delaunay_triangulation_off_visitor_reader { + private: + Complex* _complex; + typedef typename Complex::Point Point; + + public: + + // TODO(VR) : Pass a Complex as a parameter is required, even if not used. Otherwise, compilation is KO. + + /** \brief Delaunay_triangulation_off_visitor_reader constructor + * + * @param[in] _complex_ptr pointer on a Delaunay triangulation. + */ + Delaunay_triangulation_off_visitor_reader(Complex* _complex_ptr) + : _complex(nullptr) { } + + /** \brief Off_reader visitor init implementation. + * + * The init parameters are set from OFF file header. + * Dimension value is required in order to construct Delaunay triangulation. + * + * @param[in] dim space dimension of vertices. + * @param[in] num_vertices number of vertices in the OFF file (not used). + * @param[in] num_faces number of faces in the OFF file (not used). + * @param[in] num_edges number of edges in the OFF file (not used). + */ + void init(int dim, int num_vertices, int num_faces, int num_edges) { +#ifdef DEBUG_TRACES + std::cout << "Delaunay_triangulation_off_visitor_reader::init - dim=" << dim << " - num_vertices=" << + num_vertices << " - num_faces=" << num_faces << " - num_edges=" << num_edges << std::endl; +#endif // DEBUG_TRACES + if (num_faces > 0) { + std::cerr << "Delaunay_triangulation_off_visitor_reader::init faces are not taken into account from OFF " << + "file for Delaunay triangulation - faces are computed." << std::endl; + } + if (num_edges > 0) { + std::cerr << "Delaunay_triangulation_off_visitor_reader::init edges are not taken into account from OFF " << + "file for Delaunay triangulation - edges are computed." << std::endl; + } + // Complex construction with dimension from file + _complex = new Complex(dim); + } + + /** \brief Off_reader visitor point implementation. + * + * The point function is called on each vertex line from OFF file. + * This function inserts the vertex in the Delaunay triangulation. + * + * @param[in] point vector of vertex coordinates. + */ + void point(const std::vector<double>& point) { +#ifdef DEBUG_TRACES + std::cout << "Delaunay_triangulation_off_visitor_reader::point "; + for (auto coordinate : point) { + std::cout << coordinate << " | "; + } + std::cout << std::endl; +#endif // DEBUG_TRACES + _complex->insert(Point(point.size(), point.begin(), point.end())); + } + + // Off_reader visitor maximal_face implementation - not used + void maximal_face(const std::vector<int>& face) { + // For Delaunay Triangulation, only points are read + } + + // Off_reader visitor done implementation - not used + void done() { + // Nothing to be done on end of OFF file read + } + + /** \brief Returns the constructed Delaunay triangulation. + * + * @return A pointer on the Delaunay triangulation. + * + * @warning The returned pointer can be nullptr. + */ + Complex* get_complex() const { + return _complex; + } +}; + +/** \brief OFF file reader implementation in order to construct a Delaunay triangulation. + * + * This class is using the Delaunay_triangulation_off_visitor_reader to visit the OFF file according to Off_reader. + * + * For more informations on CGAL Delaunay triangulation, please refer to the corresponding chapter in page + * http://doc.cgal.org/latest/Triangulation/ + * + * \section Example + * + * This example loads points from an OFF file and builds the Delaunay triangulation. + * Then, it is asked to display the number of vertices and finites full cells from the Delaunay triangulation. + * + * \include Delaunay_triangulation_off_rw.cpp + * + * When launching: + * + * \code $> ./dtoffrw ../../data/points/alphashapedoc.off triangulated.off + * \endcode + * + * the program output is: + * + * \include dtoffrw_alphashapedoc_result.txt + */ +template<typename Complex> +class Delaunay_triangulation_off_reader { + public: + + /** \brief Reads the OFF file and constructs the Delaunay triangulation from the points + * that are in the OFF file. + * + * @param[in] name_file OFF file to read. + * + * @warning Check with is_valid() function to see if read operation was successful. + */ + Delaunay_triangulation_off_reader(const std::string & name_file) + : valid_(false) { + std::ifstream stream(name_file); + if (stream.is_open()) { + Delaunay_triangulation_off_visitor_reader<Complex> off_visitor(_complex); + Off_reader off_reader(stream); + valid_ = off_reader.read(off_visitor); + if (valid_) { + _complex = off_visitor.get_complex(); + if (_complex == nullptr) { + std::cerr << "Delaunay_triangulation_off_reader::Delaunay_triangulation_off_reader off_visitor returns an empty pointer" << std::endl; + valid_ = false; + } + } + } else { + std::cerr << "Delaunay_triangulation_off_reader::Delaunay_triangulation_off_reader could not open file " << + name_file << std::endl; + } + + } + + /** \brief Returns if the OFF file read operation was successful or not. + * + * @return OFF file read status. + */ + bool is_valid() const { + return valid_; + } + + /** \brief Returns the constructed Delaunay triangulation. + * + * @return A pointer on the Delaunay triangulation. + * + * @warning The returned pointer can be nullptr. + */ + Complex* get_complex() const { + if (valid_) + return _complex; + return nullptr; + + } + + private: + /** \brief OFF file read status.*/ + bool valid_; + /** \brief A pointer on the Delaunay triangulation.*/ + Complex* _complex; +}; + +/** \brief OFF file writer from a Delaunay triangulation. + * + * This class constructs the OFF file header according to http://www.geomview.org/docs/html/OFF.html + * + * The header is followed by the list of points coordinates (Delaunay triangulation vertices) + * + * And finally is followed by the list of faces (Delaunay triangulation finite full cells) + * + * For more informations on CGAL Delaunay triangulation, please refer to the corresponding chapter in page + * http://doc.cgal.org/latest/Triangulation/ + * + * \section Example + * + * This example loads points from an OFF file and builds the Delaunay triangulation. + * Then, the Delaunay triangulation is saved in a new file including the triangulation as a list of faces. + * + * \include Delaunay_triangulation_off_rw.cpp + * + * When launching: + * + * \code $> ./dtoffrw ../../data/points/alphashapedoc.off triangulated.off + * \endcode + * + * The result will be an OFF file of dimension 2 with the 7 points from alphashapedoc.off followed by the 6 + * triangulations of dimension 3 (the first value on each faces): + * \include dtoffrw_alphashapedoc_result.off + */ +template<typename Complex> +class Delaunay_triangulation_off_writer { + public: + typedef typename Complex::Point Point; + + /** \brief Writes the OFF file from the Delaunay triangulation + * + * @param[in] name_file OFF file to write. + * @param[in] complex_ptr pointer on a Delaunay triangulation. + * + * @warning Check with is_valid() function to see if write operation was successful. + */ + Delaunay_triangulation_off_writer(const std::string & name_file, Complex* complex_ptr) + : valid_(false) { + std::ofstream stream(name_file); + if (stream.is_open()) { + if (complex_ptr->current_dimension() == 3) { + // OFF header + stream << "OFF" << std::endl; + // no endl on next line - don't know why... + stream << complex_ptr->number_of_vertices() << " " << complex_ptr->number_of_finite_full_cells() << " 0"; + } else { + // nOFF header + stream << "nOFF" << std::endl; + // no endl on next line - don't know why... + stream << complex_ptr->current_dimension() << " " << complex_ptr->number_of_vertices() << " " << + complex_ptr->number_of_finite_full_cells() << " 0"; + + } + + // bimap to retrieve vertex handles from points and vice versa + std::map< Point, int > points_to_vh; + // Start to insert at default handle value + int vertex_handle = int(); + + // Points list + for (auto vit = complex_ptr->vertices_begin(); vit != complex_ptr->vertices_end(); ++vit) { + for (auto Coord = vit->point().cartesian_begin(); Coord != vit->point().cartesian_end(); ++Coord) { + stream << *Coord << " "; + } + stream << std::endl; + points_to_vh[vit->point()] = vertex_handle; + vertex_handle++; + } + + for (auto cit = complex_ptr->finite_full_cells_begin(); cit != complex_ptr->finite_full_cells_end(); ++cit) { + std::vector<int> vertexVector; + stream << std::distance(cit->vertices_begin(), cit->vertices_end()) << " "; + for (auto vit = cit->vertices_begin(); vit != cit->vertices_end(); ++vit) { + stream << points_to_vh[(*vit)->point()] << " "; + } + stream << std::endl; + } + stream.close(); + valid_ = true; + } else { + std::cerr << "Delaunay_triangulation_off_writer::Delaunay_triangulation_off_writer could not open file " << + name_file << std::endl; + } + } + + /** \brief Returns if the OFF write operation was successful or not. + * + * @return OFF file write status. + */ + bool is_valid() const { + return valid_; + } + + private: + /* \brief OFF file write status. */ + bool valid_; +}; + +} // namespace Gudhi + +#endif // SRC_ALPHA_SHAPES_INCLUDE_GUDHI_ALPHA_SHAPES_DELAUNAY_TRIANGULATION_OFF_IO_H_ |