80 lines
2.5 KiB
Java
80 lines
2.5 KiB
Java
package com.parseSystem.utils.eventRuleJudge;
|
||
|
||
import java.awt.geom.Point2D;
|
||
import java.util.List;
|
||
/**
|
||
* 电子围栏判定规则类
|
||
*/
|
||
public class PolygonUtil {
|
||
/**
|
||
* 发现给定点是否在给定多边形内
|
||
* @param point 给定点
|
||
* @param pts 给定的多边形顶点列表
|
||
* @return 如果给定点在多边形内，则返回true；否则返回false
|
||
*/
|
||
public static boolean isInPolygon(Point2D.Double point, List<Point2D.Double> pts){
|
||
int N = pts.size();
|
||
boolean boundOrVertex = true;
|
||
int intersectCount = 0;//交叉点数量
|
||
double precision = 2e-10;//浮点类型计算时候与0比较时候的容差
|
||
Point2D.Double p1, p2;//临近顶点
|
||
Point2D.Double p = point; //当前点
|
||
|
||
p1 = pts.get(0);
|
||
for (int i = 1; i <= N; i++) {
|
||
if(p.equals(p1)){
|
||
return boundOrVertex;
|
||
}
|
||
|
||
p2 = pts.get(i % N);
|
||
if(p.x < Math.min(p1.x,p2.x) || p.x > Math.max(p1.x, p2.x)){
|
||
p1=p2;
|
||
continue;
|
||
}
|
||
|
||
//射线穿过算法
|
||
if(p.x > Math.min(p1.x, p2.x) && p.x < Math.max(p1.x, p2.x)){
|
||
if(p.y <= Math.max(p1.y, p2.y)){
|
||
if(p1.x == p2.x && p.y >= Math.min(p1.y, p2.y)){
|
||
return boundOrVertex;
|
||
}
|
||
|
||
if(p1.y == p2.y){
|
||
if(p1.y == p.y){
|
||
return boundOrVertex;
|
||
}else{
|
||
++intersectCount;
|
||
}
|
||
}else{
|
||
double xinters = (p.x - p1.x) * (p2.y - p1.y) / (p2.x - p1.x) + p1.y;
|
||
if(Math.abs(p.y - xinters) < precision){
|
||
return boundOrVertex;
|
||
}
|
||
|
||
if(p.y < xinters){
|
||
++intersectCount;
|
||
}
|
||
}
|
||
}
|
||
}else{
|
||
if(p.x == p2.x && p.y <= p2.y){
|
||
Point2D.Double p3 = pts.get((i+1) % N);
|
||
|
||
if(p.x >= Math.min(p1.x, p3.x) && p.x <= Math.max(p1.x, p3.x)){
|
||
++intersectCount;
|
||
intersectCount += 2 ;
|
||
}
|
||
}
|
||
}
|
||
p1 = p2;
|
||
}
|
||
if (intersectCount % 2 ==0){
|
||
return false;
|
||
}else {
|
||
return true;
|
||
}
|
||
}
|
||
|
||
|
||
}
|