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记录自己用ArcGIS JavaScript 4.x实现以点(Point)为中心生成任意长宽的矩形缓冲区的效果。关键是通过中心点坐标，长，宽作为条件计算出各顶点坐标来绘制出一个类型为矩形多边形(polygon)的图形。下图是演示效果:

绘制矩形缓冲相关代码:

/** * 绘制长方形缓冲的方法 * 中心点-[lon,lat] * 长-width * 宽-height */ function getRectangleBuffer (centerPt, width, height) { var xieLineDis = Math.sqrt(width * width + height * height); var Tdegs = deg(Math.atan(width / height)); //弧度转换为度数 var coordTopLeft = distanceAngle({ lon: centerPt[0], lat: centerPt[1] }, -Tdegs, xieLineDis / 2); //左上角坐标 var coordTopRight = distanceAngle({ lon: centerPt[0], lat: centerPt[1] }, Tdegs, xieLineDis / 2); //右上角 var coordBottomLeft = distanceAngle({ lon: centerPt[0], lat: centerPt[1] }, -(180 - Tdegs), xieLineDis / 2); //左下角 var coordBootomRight = distanceAngle({ lon: centerPt[0], lat: centerPt[1] }, 180 - Tdegs, xieLineDis / 2); //右下角 //构建一个polygon所需的环形数组 var points = [ [coordTopLeft.lon, coordTopLeft.lat], [coordTopRight.lon, coordTopRight.lat], [coordBootomRight.lon, coordBootomRight.lat], [coordBottomLeft.lon, coordBottomLeft.lat] ] //右上角的点，用来同步放大矩形 var scalePt = new Point({ longitude: coordTopRight.lon, latitude: coordTopRight.lat, spatialReference: view.spatialReference }) var scaleSym = { type: "simple-marker", color: [266, 266, 266, 0.8] } scaleGp = new Graphic({ geometry: scalePt, symbol: scaleSym, attributes: { name: "rectangleGp" } }) view.graphics.add(scaleGp) var polygon = new Polygon({ rings: points }) var recsymbol = { type: "simple-fill", color: [267, 267, 0] } var rectangleGp = new Graphic({ geometry: polygon, symbol: recsymbol }) return rectangleGp; }

完整demo下载地址:https://download.csdn.net/download/lf5566fl/12089174