\( \newcommand{\E}{\mathrm{E}} \) \( \newcommand{\A}{\mathrm{A}} \) \( \newcommand{\R}{\mathrm{R}} \) \( \newcommand{\N}{\mathrm{N}} \) \( \newcommand{\Q}{\mathrm{Q}} \) \( \newcommand{\Z}{\mathrm{Z}} \) \( \def\ccSum #1#2#3{ \sum_{#1}^{#2}{#3} } \def\ccProd #1#2#3{ \sum_{#1}^{#2}{#3} }\)
CGAL 4.12.2 - 2D Arrangements
Arrangement_on_surface_2/global_removal.cpp
// Using the global removal functions.
#include <CGAL/Cartesian.h>
#include <CGAL/Arr_linear_traits_2.h>
#include <CGAL/Arrangement_2.h>
#include <CGAL/Arr_naive_point_location.h>
#include "arr_print.h"
typedef int Number_type;
typedef Traits_2::Point_2 Point_2;
typedef Traits_2::X_monotone_curve_2 Segment_2;
typedef CGAL::Arrangement_2<Traits_2> Arrangement_2;
typedef Arrangement_2::Vertex_handle Vertex_handle;
typedef Arrangement_2::Halfedge_handle Halfedge_handle;
int main ()
{
// Create an arrangement of four line segments forming an H-shape:
Arrangement_2 arr;
Segment_2 s1 (Point_2(1, 3), Point_2(4, 3));
Halfedge_handle e1 = arr.insert_in_face_interior (s1, arr.unbounded_face());
Segment_2 s2 (Point_2(1, 4), Point_2(4, 4));
Halfedge_handle e2 = arr.insert_in_face_interior (s2, arr.unbounded_face());
insert(arr, Segment_2(Point_2(1, 1), Point_2(1, 6)));
insert(arr, Segment_2(Point_2(4, 1), Point_2(4, 6)));
std::cout << "The initial arrangement:" << std::endl;
print_arrangement (arr);
// Remove e1 and its incident vertices using the function remove_edge().
Vertex_handle v1 = e1->source(), v2 = e1->target();
arr.remove_edge(e1);
remove_vertex(arr, v1);
remove_vertex(arr, v2);
// Remove e2 using the free remove_edge() function.
remove_edge (arr, e2);
std::cout << "The final arrangement:" << std::endl;
print_arrangement (arr);
return 0;
}