cgal/Packages/Planar_map/examples/Planar_map/example5.C

60 lines
1.8 KiB
C

/*! \file
* A construction of a quadrilateral-shaped Planar_map.
* In this example a quadrilateral-shaped Planar_map that uses the naive point
* location strategy is constructed utilising various edge-insertion
* operations, that is insert_in_face_interior(), insert_from_vertex(), and
* insert_at_vertices(). The later is verfiried to return the halfedge that is
* incident to the unbounded face.
*/
#include "short_names.h"
#include <CGAL/Homogeneous.h>
#include <CGAL/Pm_segment_traits_2.h>
#include <CGAL/Pm_default_dcel.h>
#include <CGAL/Planar_map_2.h>
#include <CGAL/Pm_naive_point_location.h>
#include <iostream>
typedef CGAL::Homogeneous<long> Kernel;
typedef CGAL::Pm_segment_traits_2<Kernel> Traits;
typedef Traits::Point_2 Point_2;
typedef Traits::X_curve_2 X_curve_2;
typedef CGAL::Pm_default_dcel<Traits> Dcel;
typedef CGAL::Planar_map_2<Dcel,Traits> Planar_map;
int main()
{
// Create an instance of a Planar_map with a naive point location strategy:
CGAL::Pm_naive_point_location<Planar_map> naive_pl;
Planar_map pm(&naive_pl);
X_curve_2 cv[4];
int i;
CGAL::set_ascii_mode(std::cout);
Point_2 a1(0, 0), a2(1, 0), a3(1, 1), a4(0, 1);
// Create the curves:
cv[0] = X_curve_2(a1, a2);
cv[1] = X_curve_2(a2, a3);
cv[2] = X_curve_2(a3, a4);
cv[3] = X_curve_2(a4, a1);
// Insert the curves into the Planar_map:
Planar_map::Halfedge_handle e[4];
e[0] = pm.insert_in_face_interior(cv[0], pm.unbounded_face());
for (i = 1; i < 3; i++)
e[i] = pm.insert_from_vertex(cv[i], e[i-1]->target());
e[3] = pm.insert_at_vertices(cv[3], e[0]->source(), e[2]->target());
// Check for correct topology:
CGAL_assertion(e[3]->face()->is_unbounded());
// Check the validity of the map:
CGAL_assertion(pm.is_valid());
return 0;
}