CGAL 5.2.1 - 2D Polygon Partitioning
Partition_2/y_monotone_partition_indices_2.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/partition_2.h>
#include <CGAL/Partition_traits_2.h>
#include <CGAL/property_map.h>
#include <vector>
#include <cassert>
#include <list>
typedef Partition_traits_2::Point_2 Point_2;
typedef Partition_traits_2::Polygon_2 Polygon_2; // a polygon of indices
typedef std::list<Polygon_2> Polygon_list;
/*
v4 v2
| \ /|
| \ / |
| v3 |
| |
v0-----v1
*/
int main( )
{
std::vector<K::Point_2> points = { K::Point_2(0,0), K::Point_2(2,0), K::Point_2(2,2), K::Point_2(1,1), K::Point_2(0,2) };
Partition_traits_2 traits(CGAL::make_property_map(points));
Polygon_2 polygon;
polygon.push_back(0);
polygon.push_back(1);
polygon.push_back(2);
polygon.push_back(3);
polygon.push_back(4);
Polygon_list partition_polys;
CGAL::y_monotone_partition_2(polygon.vertices_begin(),
polygon.vertices_end(),
std::back_inserter(partition_polys),
traits);
for (const Polygon_2& poly : partition_polys){
for(Point_2 p : poly.container()){
std::cout << "points[" << p << "] = " << points[p] << ", ";
}
std::cout << std::endl;
}
assert(CGAL::partition_is_valid_2(polygon.vertices_begin(),
polygon.vertices_end(),
partition_polys.begin(),
partition_polys.end(),
traits));
return 0;
}