OpenLayers - 如何从现有的 lonLat 点绘制多边形？

Question

我的数据库中有来自用户定义多边形的经纬度顶点。我的问题是:我现在如何在 map 上重新创建和显示它们？使用 Google Maps API 很容易做到这一点，但我找不到关于如何使用 OpenLayers 做到这一点的任何文档或示例。有没有人有这样做的经验？

Answer 1

经过大量的实验，我发现了如何做到这一点:

let sitePoints = [];
let siteStyle = {
  // style_definition
};

let epsg4326 = new OpenLayers.Projection("EPSG:4326");
for (let i in coordinates) {
  let coord = coordinates[i];
  let point = new OpenLayers.Geometry.Point(coord.lng, coord.lat);
  // transform from WGS 1984 to Spherical Mercator
  point.transform(epsg4326, map.getProjectionObject());
  sitePoints.push(point);
}
sitePoints.push(sitePoints[0]);

let linearRing = new OpenLayers.Geometry.LinearRing(sitePoints);
let geometry = new OpenLayers.Geometry.Polygon([linearRing]);
let polygonFeature = new OpenLayers.Feature.Vector(geometry, null, siteStyle);
vectors.addFeatures([polygonFeature]);