当我显示超过 2000 个多边形和/或线串时会出现问题，地图的平移和缩放变慢，osm 图块的加载也变慢。当视口中可见的特征较少（放大或远离特征）时，问题就消失了。我认为这不是样式问题，因为标准 openlayers 样式也会出现这种情况。
由于代码片段的限制，我只能将真实数据的一些特征添加到地图中，不幸的是，这个问题在如此大量的数据中是不可见的。但也许有人会发现代码有问题，或者有更好的方法在矢量图层上显示大量多边形/线串。
<html lang="en">
<head>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.5.0/css/ol.css" type="text/css">
<style>
.map {
height: 95vh;
width: 100%;
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<script src="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.5.0/build/ol.js"></script>
<title>OpenLayers example</title>
</head>
<body>
<h2>My Map</h2>
<div id="map" class="map"></div>
<script type="text/javascript">
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features: new ol.format.GeoJSON().readFeatures(JSON.stringify(geoJsonData)),
})
});
var map = new ol.Map({
target: 'map',
layers: [
new ol.layer.Tile({
source: new ol.source.OSM()
}),
vectorLayer
],
view: new ol.View({
center: [vectorLayer.getSource().getExtent()[0], vectorLayer.getSource().getExtent()[1]],
zoom: 13
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});
</script>
</body>
</html>答案 0 :(得分：1)
我使用 VectorImageLayer 修复了它，似乎比普通的 VectorLayer 快很多
答案 1 :(得分：0)
你应该使用 tilelayer 来处理海量数据。如果您没有地理服务器等，请geojsonvt plugin 创建动态磁贴。 GeojsonVT 可以轻松渲染 15 万多个具有大量属性值的特征。