cgal/Packages/Arrangement/examples/Arrangement_2/example13.C

101 lines
3.2 KiB
C

// file: examples/Arrangement_2/example3.C
#include "short_names.h"
#ifndef CGAL_USE_LEDA
// To enable compilation without leda:
int main ()
{
return (0);
}
#else
#include <CGAL/basic.h>
#include <CGAL/Cartesian.h>
#include <CGAL/leda_real.h>
#include <CGAL/Arr_2_bases.h>
#include <CGAL/Arr_2_default_dcel.h>
#include <CGAL/Arr_conic_traits_2.h>
#include <CGAL/Arrangement_2.h>
typedef leda_real NT;
typedef CGAL::Cartesian<NT> Kernel;
typedef CGAL::Arr_conic_traits_2<Kernel> Traits;
typedef Traits::Point_2 Point_2;
typedef Traits::Segment_2 Segment_2;
typedef Traits::Circle_2 Circle_2;
typedef Traits::Curve_2 Curve_2;
typedef Traits::X_monotone_curve_2 X_monotone_curve_2;
typedef CGAL::Arr_base_node<Curve_2, X_monotone_curve_2> Base_node;
typedef CGAL::Arr_2_default_dcel<Traits> Dcel;
typedef CGAL::Arrangement_2<Dcel,Traits,Base_node> Arr_2;
int main()
{
Arr_2 arr;
// Insert a hyperbolic arc, supported by the hyperbola y = 1/x
// (or: xy - 1 = 0) with the end-points (0.25, 4) and (2, 0.5).
Point_2 ps1 (0.25, 4);
Point_2 pt1 (2, 0.5);
Curve_2 c1 (0, 0, 1, 0, 0, -1, ps1, pt1);
arr.insert(c1);
// Insert a full ellipse, which is (x/4)^2 + (y/2)^2 = 0 rotated by
// phi=36.87 degree (such that sin(phi) = 0.6, cos(phi) = 0.8),
// yielding: 58x^2 + 72y^2 - 48xy - 360 = 0.
Curve_2 c2 (58, 72, -48, 0, 0, -360);
arr.insert(c2);
// Insert the segment (1, 1) -- (0, -3).
Point_2 ps3 (1, 1);
Point_2 pt3 (0, -3);
Curve_2 c3 (Segment_2 (ps3, pt3));
arr.insert(c3);
// Insert a circular arc supported by the circle x^2 + y^2 = 5^2,
// with (-3, 4) and (4, 3) as its endpoints.
Point_2 ps4 (-3, 4);
Point_2 pt4 (4, 3);
Circle_2 circ4 (Point_2(0,0), 5*5, CGAL::CLOCKWISE);
Curve_2 c4 (circ4, ps4, pt4);
arr.insert(c4);
// Insert a full unit circle that is centered at (0, 4).
Circle_2 circ5 (Point_2(0,4), 1*1, CGAL::COUNTERCLOCKWISE);
Curve_2 c5 (circ5);
arr.insert(c5);
// Insert a parabolic arc that is supported by a parabola y = -x^2
// (or: x^2 + y = 0) and whose end-points are (-sqrt(3), -3) ~ (-1.73, -3)
// and (sqrt(2), -2) ~ (1.41, -2). Notice that since the x-coordinates
// of the end-points cannot be acccurately represented, we specify them
// as the intersections of the parabola with the lines y = -3 and y = -2.
Curve_2 c6 (1, 0, 0, 0, 1, 0, // The parabola.
Point_2 (-1.73, -3), // Approximation of the source.
0, 0, 0, 0, 1, 3, // The line: y = -3.
Point_2 (1.41, -2), // Approximation of the target.
0, 0, 0, 0, 1, 2); // The line: y = -2.
arr.insert(c6);
// Print out the number of vertices, edges and faces in the arrangement.
std::cout << "Number of vertices: "
<< arr.number_of_vertices() << std::endl;
std::cout << "Number of edges: "
<< arr.number_of_halfedges()/2 << std::endl;
std::cout << "Number of faces: "
<< arr.number_of_faces() << std::endl;
return 0;
}
#endif