openlayers2 开发如何判断一个marker所在的点是否在一个多边形内部
如图所示,如何取出用OpenLayers.Control.DrawFeature画出来多边形所包围那个点而不被其他点干扰。
JS代码(写在画图工具的featureAdded(f)方法内):
var components = f.geometry.components,//f为OpenLayers_Feature_Vector类型的对象
bottom = f.geometry.bounds.bottom, top = f.geometry.bounds.top, left = f.geometry.bounds.left, right = f.geometry.bounds.right, components = f.geometry.components; $.each(markers,function (i,marker) { //markers为所有marker lat = marker.lonlat.lat, lon = marker.lonlat.lon; //判断marker所在的位置是否在多边形内部 if(lat>bottom&&lat<top&&lon>left&&lon<right){//首先判断点是不是在多边形的边界也就是矩形框内部 var k, j, c = 0; var length = components.length; for (k = 0, j = length-1; k < length; j = k++) { if (((components[k].y>lat) != (components[j].y>lat) ) && (lon < (components[j].x-components[k].x)*(lat-components[k].y)/(components[j].y-components[k].y)+components[k].x)) c = !c; } if(c){ //TODO 进入这个if说明是在多边形内 现在要写自己的逻辑了 } } });
转载自:https://blog.csdn.net/pengmaoming/article/details/71172573