原文来自
前端时间遇到个问题，就是判断百度地图里的多个任意多边形区域是否重复，在网上看了很多的文章都没有找到解决方案，功夫不负有心人，在网上找到个可以判断是否重复的，但是在包含的情况下就不能判断，后来自己加入根据点判断点是否在多边形内来判断重复，问题已解决，在此把代码贴出来，供大家参考
//#region 验证两个面是否相交的算法 (此函数摘抄自网络)function intersectsPolygonAndPolygon (polygon1LinearRings, polygon2LinearRings) {// polygon1LinearRings : array[LinearRing,...]function intersectsByPolygon (polygon1LinearRings, polygon2LinearRings) {var intersect = false;intersect = intersectsByLinearRings(polygon1LinearRings, polygon2LinearRings);if(!intersect) { // check if this poly contains points of the ring/linestring for(i=0, len=polygon2LinearRings.length; i 0) { contained = containsPointByLinearRing(point, LinearRings[0]); if( numRings > 1) { // check interior rings var hole; for(var i=1; i 0) { fig = parseFloat(num.toPrecision(sig)); } return fig;}var digs = 14;var px = approx(point.x, digs);var py = approx(point.y, digs);function getX(y, x1, y1, x2, y2) { return (y - y2) * ((x2 - x1) / (y2 - y1)) + x2;}var numSeg = LinearRing.length - 1;var start, end, x1, y1, x2, y2, cx, cy;var crosses = 0;for(var i=0; i = x1 && px <= x2) || // right or vert x1 >= x2 && (px <= x1 && px >= x2)) { // left or vert // point on edge crosses = -1; break; } } // ignore other horizontal edges continue; } cx = approx(getX(py, x1, y1, x2, y2), digs); if(cx == px) { // point on line if(y1 < y2 && (py >= y1 && py <= y2) || // upward y1 > y2 && (py <= y1 && py >= y2)) { // downward // point on edge crosses = -1; break; } } if(cx <= px) { // no crossing to the right continue; } if(x1 != x2 && (cx < Math.min(x1, x2) || cx > Math.max(x1, x2))) { // no crossing continue; } if(y1 < y2 && (py >= y1 && py < y2) || // upward y1 > y2 && (py < y1 && py >= y2)) { // downward ++crosses; }}var contained = (crosses == -1) ? // on edge 1 : // even (out) or odd (in) !!(crosses & 1);return contained;}function intersectsByLinearRings (LinearRing1, LinearRings2) {var intersect = false;var segs1 = getSortedSegments(LinearRing1);var segs2 = getSortedSegments(LinearRings2);var seg1, seg1x1, seg1x2, seg1y1, seg1y2, seg2, seg2y1, seg2y2;// sweep rightouter: for(var i=0, len=segs1.length; i seg1x2) { // seg1 still left of seg2 break; } if(seg2.x2 < seg1x1) { // seg2 still left of seg1 continue; } seg2y1 = seg2.y1; seg2y2 = seg2.y2; if(Math.min(seg2y1, seg2y2) > Math.max(seg1y1, seg1y2)) { // seg2 above seg1 continue; } if(Math.max(seg2y1, seg2y2) < Math.min(seg1y1, seg1y2)) { // seg2 below seg1 continue; } if(segmentsIntersect(seg1, seg2)) { intersect = true; break outer; } }}return intersect;}function getSortedSegments(points) {var numSeg = points.length - 1;var segments = new Array(numSeg), point1, point2;for(var i=0; i = 0 && along1 <= 1 && along2 >=0 && along2 <= 1) { // intersect if(!point) { intersection = true; } else { // calculate the intersection point var x = seg1.x1 + (along1 * x12_11); var y = seg1.y1 + (along1 * y12_11); intersection = { 'x':x, 'y':y }; } }}if(tolerance) { var dist; if(intersection) { if(point) { var segs = [seg1, seg2]; var seg, x, y; // check segment endpoints for proximity to intersection // set intersection to first endpoint within the tolerance outer: for(var i=0; i<2; ++i) { seg = segs[i]; for(var j=1; j<3; ++j) { x = seg["x" + j]; y = seg["y" + j]; dist = Math.sqrt( Math.pow(x - intersection.x, 2) + Math.pow(y - intersection.y, 2) ); if(dist < tolerance) { intersection.x = x; intersection.y = y; break outer; } } } } } else { // no calculated intersection, but segments could be within // the tolerance of one another var segs = [seg1, seg2]; var source, target, x, y, p, result; // check segment endpoints for proximity to intersection // set intersection to first endpoint within the tolerance outer: for(var i=0; i<2; ++i) { source = segs[i]; target = segs[(i+1)%2]; for(var j=1; j<3; ++j) { p = {x: source["x"+j], y: source["y"+j]}; result = distanceToSegment(p, target); if(result.distance < tolerance) { if(point) { intersection = { 'x':p.x, 'y':p.y }; } else { intersection = true; } break outer; } } } }}return intersection;};function distanceToSegment(point, segment) {var result = distanceSquaredToSegment(point, segment);result.distance = Math.sqrt(result.distance);return result;};function distanceSquaredToSegment(point, segment) {var x0 = point.x;var y0 = point.y;var x1 = segment.x1;var y1 = segment.y1;var x2 = segment.x2;var y2 = segment.y2;var dx = x2 - x1;var dy = y2 - y1;var along = ((dx * (x0 - x1)) + (dy * (y0 - y1))) / (Math.pow(dx, 2) + Math.pow(dy, 2));var x, y;if(along <= 0.0) { x = x1; y = y1;} else if(along >= 1.0) { x = x2; y = y2;} else { x = x1 + along * dx; y = y1 + along * dy;}return { distance: Math.pow(x - x0, 2) + Math.pow(y - y0, 2), x: x, y: y, along: along};}return intersectsByPolygon(polygon1LinearRings, polygon2LinearRings);}//#endregionfunction railsIsOverlap (rails) {var i, j, k, v, l, n;if (rails.length < 2) {return false;}for (i = 0, j = rails.length - 1; i < j; i++) {var rail = rails[i];var railPath = rail.getPath();for (k = i + 1, v = rails.length; k < v; k++) { var railed = rails[k]; var railedPath = railed.getPath(); for (l = 0 , n = railPath.length; l < n; l ++) { if (BMapLib.GeoUtils.isPointInPolygon(new BMap.Point(railPath[l].lng, railPath[l].lat), railed)) { layer.alert("片区不能重复"); return true; } } for (l = 0, n = railedPath.length; l < n; l ++) { if (BMapLib.GeoUtils.isPointInPolygon(new BMap.Point(railedPath[l].lng, railedPath[l].lat), rail)) { // console.log(53) layer.alert("片区不能重复"); return true; } }}}var lines = [];for ( i = 0 ; i < rails.length; i ++) {var line = rails[i].getPath();lines.push([]);for (j = 0 ;j < line.length ; j ++) { var p = { x: line[j].lng, y: line[j].lat }; lines[i].push(p);}lines[i].push(lines[i][0])}for (i = 0; i < lines.length - 1; i ++) {var p1 = lines[i];for (j = i + 1; j < lines.length; j ++) { var p2 = lines[j]; if (intersectsPolygonAndPolygon(p1,p2)) { layer.alert("片区不能重复！"); return true; }}}return false;} 使用时直接调用railsIsOverlap函数就行，参数是多边形数组