CGAL三角剖分：

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>  
#include <CGAL/Constrained_Delaunay_triangulation_2.h>  
#include <CGAL/Triangulation_conformer_2.h>  
#include <iostream>  
typedef CGAL::Exact_predicates_inexact_constructions_kernel K;  
typedef CGAL::Constrained_Delaunay_triangulation_2<K> CDT;  
typedef CDT::Point Point;  
typedef CDT::Vertex_handle Vertex_handle;  
int main()  
{
     
  CDT cdt;  
  // construct a constrained triangulation  
  Vertex_handle  
    va = cdt.insert(Point( 5., 5.)),  
    vb = cdt.insert(Point(-5., 5.)),  
    vc = cdt.insert(Point( 4., 3.)),  
    vd = cdt.insert(Point( 5.,-5.)),  
    ve = cdt.insert(Point( 6.