\( \newcommand{\E}{\mathrm{E}} \) \( \newcommand{\A}{\mathrm{A}} \) \( \newcommand{\R}{\mathrm{R}} \) \( \newcommand{\N}{\mathrm{N}} \) \( \newcommand{\Q}{\mathrm{Q}} \) \( \newcommand{\Z}{\mathrm{Z}} \) \( \def\ccSum #1#2#3{ \sum_{#1}^{#2}{#3} } \def\ccProd #1#2#3{ \sum_{#1}^{#2}{#3} }\)
CGAL 5.0.3 - 2D Arrangements
Arrangement_on_surface_2/io_curve_history.cpp
// Using the arrangement-with-history I/O operators.
#include <CGAL/Cartesian.h>
#include <CGAL/Arr_segment_traits_2.h>
#include <CGAL/Arrangement_with_history_2.h>
#include <CGAL/IO/Arr_with_history_iostream.h>
#include <fstream>
typedef Traits_2::Point_2 Point_2;
typedef Traits_2::Curve_2 Segment_2;
int main ()
{
Arr_with_hist_2 arr;
// Insert six additional segments aggregately:
Segment_2 segs[6];
segs[0] = Segment_2 (Point_2 (2, 6), Point_2 (7, 1));
segs[1] = Segment_2 (Point_2 (3, 2), Point_2 (3, 5));
segs[2] = Segment_2 (Point_2 (2, 3), Point_2 (5, 3));
segs[3] = Segment_2 (Point_2 (2, 6), Point_2 (7, 1));
segs[4] = Segment_2 (Point_2 (0, 0), Point_2 (2, 6));
segs[5] = Segment_2 (Point_2 (3, 4), Point_2 (6, 4));
insert (arr, segs, segs + 6);
std::cout << "Writing an arrangement of "
<< arr.number_of_curves() << " input segments:" << std::endl
<< " V = " << arr.number_of_vertices()
<< ", E = " << arr.number_of_edges()
<< ", F = " << arr.number_of_faces() << std::endl;
// Write the arrangement to a file.
std::ofstream out_file ("arr_ex_io_hist.dat");
out_file << arr;
out_file.close();
// Read the arrangement from the file.
Arr_with_hist_2 arr2;
std::ifstream in_file ("arr_ex_io_hist.dat");
in_file >> arr2;
in_file.close();
std::cout << "Read an arrangement of "
<< arr2.number_of_curves() << " input segments:" << std::endl
<< " V = " << arr2.number_of_vertices()
<< ", E = " << arr2.number_of_edges()
<< ", F = " << arr2.number_of_faces() << std::endl;
return (0);
}