使用cgal计算两个多边形的交集区域

Question

给定两个凸多边形的顶点，使用cgal计算其交集区域的最简单方法是什么？

Answer 1

因为您正在使用凸多边形，所以不需要担心孔。所以我能想到的最简单的代码基本上是构建多边形，调用交集，遍历交叉点和总区域：

#include <iostream> 
#include <CGAL/Simple_cartesian.h> 
#include <CGAL/Polygon_2.h> 
#include <CGAL/Polygon_with_holes_2.h> 
#include <CGAL/Boolean_set_operations_2.h> 
#include <CGAL/Polygon_2_algorithms.h> 


typedef CGAL::Simple_cartesian<double> K; 
typedef K::Point_2 Point; 
typedef CGAL::Polygon_2<K> Polygon_2; 
typedef CGAL::Polygon_with_holes_2<K> Polygon_with_holes_2; 
using std::cout; using std::endl; 


int main(){ 
    Point points[] = { Point(0,0), Point(1,0), Point(1,1), Point(0,1)}; 
    Point points2[] = { Point(0.5,0.5), Point(1.5,0.5), Point(1.5,1.5), Point(0.5,1.5)}; 
    Polygon_2 poly1(points, points+4); 
    Polygon_2 poly2(points2, points2+4); 
    //CGAL::General_polygon_with_holes_2<K> poly3; 
    std::list<Polygon_with_holes_2> polyI; 

    CGAL::intersection(poly1, poly2, std::back_inserter(polyI)); 

    double totalArea = 0; 
    typedef std::list<Polygon_with_holes_2>::iterator LIT; 
    for(LIT lit = polyI.begin(); lit!=polyI.end(); lit++){ 
    totalArea+=lit->outer_boundary().area(); 
    } 
    cout << "TotalArea::" << totalArea; 

}