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前言

分割矢量多边形

一、安装turf

npm i @turf/turf

二、加载高德

AMapLoader.load({key: "你的key", // 申请好的Web端开发者Key，首次调用 load 时必填version: "2.0", // 指定要加载的 JSAPI 的版本，缺省时默认为 1.4.15plugins: ["AMap.PolygonEditor", "AMap.LngLat", "AMap.Polygon"], // 需要使用的的插件列表，如比例尺'AMap.Scale'等}).then((AMap) => {//此处处理后续操作
}

三、绘制图形

 map = new AMap.Map("container", {// 设置地图容器idviewMode: "3D", // 是否为3D地图模式zoom: 13, // 初始化地图级别center: [116.471354, 39.994257],});// 绘制折线var polylinePath = [[116.478, 40.000296],[116.478603, 39.997534],[116.478, 40.000296],];// 创建折线实例var polyline = new AMap.Polyline({path: polylinePath,strokeColor: "#FF0000",strokeWeight: 5,lineCap: "round",});map.add(polyline); // 添加至地图// 绘制多边形var polygonPath = [[116.475334, 39.997534],[116.476627, 39.998315],[116.478603, 39.99879],[116.478529, 40.000296],[116.475082, 40.000151],[116.473421, 39.998717],[116.475334, 39.997534],];// 创建多边形实例var polygon = new AMap.Polygon({path: polygonPath,fillColor: "#FFC0CB",strokeColor: "#000000",strokeWeight: 2,});map.add(polygon); // 添加至地图

四、计算交点

 // 格式转化// 转换折线为Turf线段var turfPolyline = turf.lineString(polylinePath.map((p) => [p[0], p[1]]));// 转换多边形为Turf多边形var turfPolygon = turf.polygon([polygonPath.map((p) => [p[0], p[1]])]);// // 计算折线与多边形的交点var intersections = turf.lineIntersect(turfPolyline, turfPolygon);// 获取交点数量var intersectionCount = intersections.features.length;console.log("交点个数:", intersectionCount);console.log("交点:",intersections.features.map((i) => i.geometry.coordinates));

五、编写获取子多边形的函数

function polygonCut(poly,line,tolerance = 0.001,toleranceType = "kilometers") {// 1. 条件判断if (poly.geometry === void 0 || poly.geometry.type !== "Polygon")throw "传入的必须为polygon";if (line.geometry === void 0 ||line.geometry.type.toLowerCase().indexOf("linestring") === -1)throw "传入的必须为linestring";if (line.geometry.type === "LineString") {if (turf.booleanPointInPolygon(turf.point(line.geometry.coordinates[0]),poly) ||turf.booleanPointInPolygon(turf.point(line.geometry.coordinates[line.geometry.coordinates.length - 1]),poly))throw "起点和终点必须在多边形之外";}// 2. 计算交点，并把线的点合并let lineIntersect = turf.lineIntersect(line, poly);const lineExp = turf.explode(line);for (let i = 0; i < lineExp.features.length - 1; i++) {lineIntersect.features.push(turf.point(lineExp.features[i].geometry.coordinates));}// 3. 计算线的缓冲区const lineBuffer = turf.buffer(line, tolerance, {units: toleranceType,});// 4. 计算线缓冲和多边形的difference，返回"MultiPolygon"，所以将其拆开var _body = turf.difference(turf.featureCollection([poly, lineBuffer]));console.log(_body, 134);let pieces = [];if (_body.geometry.type === "Polygon") {pieces.push(turf.polygon(_body.geometry.coordinates));} else {_body.geometry.coordinates.forEach(function (a) {pieces.push(turf.polygon(a));});}return pieces;}

六、调用分割函数并绘制图像

let polygons = polygonCut(turfPolygon, turfPolyline);// 绘制子多边形（根据需求将数据保存只后台）var polygon1 = new AMap.Polygon({path: [polygons[0].geometry.coordinates],fillColor: "red",strokeColor: "#000000",strokeWeight: 2,});map.add(polygon1); // 添加至地图var polygon2 = new AMap.Polygon({path: [polygons[1].geometry.coordinates],fillColor: "green",strokeColor: "#000000",strokeWeight: 2,});map.add(polygon2); // 添加至地图

七、效果