CGAL 5.1.3 - 2D Polygons
Polygon/polygon_algorithms.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Polygon_2_algorithms.h>
#include <iostream>
typedef K::Point_2 Point;
using std::cout; using std::endl;
void check_inside(Point pt, Point *pgn_begin, Point *pgn_end, K traits)
{
cout << "The point " << pt;
switch(CGAL::bounded_side_2(pgn_begin, pgn_end,pt, traits)) {
cout << " is inside the polygon.\n";
break;
cout << " is on the polygon boundary.\n";
break;
cout << " is outside the polygon.\n";
break;
}
}
int main()
{
Point points[] = { Point(0,0), Point(5.1,0), Point(1,1), Point(0.5,6)};
// check if the polygon is simple.
cout << "The polygon is "
<< (CGAL::is_simple_2(points, points+4, K()) ? "" : "not ")
<< "simple." << endl;
check_inside(Point(0.5, 0.5), points, points+4, K());
check_inside(Point(1.5, 2.5), points, points+4, K());
check_inside(Point(2.5, 0), points, points+4, K());
return 0;
}