我想检查一个点是否在特定的多边形内。该多边形如下:
polygon= [ [-73.89632720118, 40.8515320489962],
[-73.8964878416508, 40.8512476593594],
[-73.8968799791431, 40.851375925454],
[-73.8967188588015, 40.851660158514],
[-73.89632720118, 40.8515320489962] ]
我想要检查的要点是:
1 = [40.8515320489962,-73.89632720118]
2 = [40.8512476593594,-73.8964878416508]
3 = [40.851375925454,-73.8968799791431]
4 = [40.851660158514,-73.8967188588015]
5 = [40.8515320489962,-73.89632720118]
我该如何判断这些点是否在多边形内部?
下面的算法不起作用,我不知道为什么。
pt[lat,long]
function isPointInPoly(poly, pt){
for(var c = false, i = -1, l = poly.length, j = l - 1; ++i < l; j = i)
((poly[i][1] <= pt[1] && pt[1] < poly[j][1]) || (poly[j][1] <= pt[1] && pt[1] < poly[i][1]))
&& (pt[0] < (poly[j][0] - poly[i][0]) * (pt[1] - poly[i][1]) / (poly[j][1] - poly[i][1]) + poly[i][0])
&& (c = !c);
return c;
}
我不想使用第三方解决方案,例如 Google Maps API 或这个 https://github.com/mattwilliamson/Google-Maps-Point-in-Polygon。
我的尝试在这里:http://jsfiddle.net/nvNNF/2/
poly[i].y
应改为poly[i][1]
。此外,该函数检查点是否在多边形内,而非点是否属于多边形。 - Ben