注： 本例使用的功能不是稳定API的一部分，可能会在不同版本之间发生变化。请参考API文档以了解最新版本中支持的内容。

原文链接及内容

原文链接：https://openlayers.org/en/latest/examples/webgl-vector-tiles.html

运行界面

使用WebGL渲染一副简单的Mapbox矢量切片地图。注：使用此示例时，请确保获取您自己的Mapbox API密钥。当API密钥过期时，将看不到地图。

main.js代码如下：

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import MVT from 'ol/format/MVT.js';
import Map from 'ol/Map.js';
import VectorTile from 'ol/layer/VectorTile.js';
import VectorTileSource from 'ol/source/VectorTile.js';
import View from 'ol/View.js';
import WebGLVectorTileLayerRenderer from 'ol/renderer/webgl/VectorTileLayer.js';
import {Fill, Icon, Stroke, Style, Text} from 'ol/style.js';
import {asArray} from 'ol/color.js';
import {packColor, parseLiteralStyle} from 'ol/webgl/styleparser.js';

const key =
  'Your Mapbox access token from https://mapbox.com/ here';

const result = parseLiteralStyle({
  'fill-color': ['get', 'fillColor'],
  'stroke-color': ['get', 'strokeColor'],
  'stroke-width': ['get', 'strokeWidth'],
  'circle-radius': 4,
  'circle-fill-color': '#777',
});

class WebGLVectorTileLayer extends VectorTile {
  createRenderer() {
    return new WebGLVectorTileLayerRenderer(this, {
      style: {
        fill: {
          fragment: result.builder.getFillFragmentShader(),
          vertex: result.builder.getFillVertexShader(),
        },
        stroke: {
          fragment: result.builder.getStrokeFragmentShader(),
          vertex: result.builder.getStrokeVertexShader(),
        },
        symbol: {
          fragment: result.builder.getSymbolFragmentShader(),
          vertex: result.builder.getSymbolVertexShader(),
        },
        attributes: {
          fillColor: {
            size: 2,
            callback: (feature) => {
              const style = this.getStyle()(feature, 1)[0];
              const color = asArray(style?.getFill()?.getColor() || '#eee');
              return packColor(color);
            },
          },
          strokeColor: {
            size: 2,
            callback: (feature) => {
              const style = this.getStyle()(feature, 1)[0];
              const color = asArray(style?.getStroke()?.getColor() || '#eee');
              return packColor(color);
            },
          },
          strokeWidth: {
            size: 1,
            callback: (feature) => {
              const style = this.getStyle()(feature, 1)[0];
              return style?.getStroke()?.getWidth() * 2 || 0;
            },
          },
        },
      },
    });
  }
}

const map = new Map({
  layers: [
    new WebGLVectorTileLayer({
      source: new VectorTileSource({
        attributions:
          '© <a href="https://www.mapbox.com/map-feedback/">Mapbox</a> ' +
          '© <a href="https://www.openstreetmap.org/copyright">' +
          'OpenStreetMap contributors</a>',
        format: new MVT(),
        url:
          'https://{a-d}.tiles.mapbox.com/v4/mapbox.mapbox-streets-v6/' +
          '{z}/{x}/{y}.vector.pbf?access_token=' +
          key,
      }),
      style: createMapboxStreetsV6Style(Style, Fill, Stroke, Icon, Text),
    }),
  ],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 2,
  }),
});

界面布局文件index.html代码如下：

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<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>WebGL Vector Tiles Layer</title>
    <link rel="stylesheet" href="node_modules/ol/ol.css">
    <style>
      .map {
        width: 100%;
        height: 400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>

    <script src="https://openlayers.org/en/v8.1.0/examples/resources/mapbox-streets-v6-style.js"></script>
    <script type="module" src="main.js"></script>
  </body>
</html>