原文链接及内容

原文链接：https://openlayers.org/en/latest/examples/mapbox-layer.html

运行界面

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。

演示如何在OpenLayers地图中添加mapbox-gl-js图层。注意:在使用此示例时，请确保在https://www.maptiler.com/cloud/ 上获取自己的API密钥。当API密钥过期时，将看不到地图。在这个例子中使用Mapbox-gl-js版本是1.13.0，因为该版本之后的版本需要Mapbox访问令牌，并且与旧的浏览器不兼容。

main.js代码如下：

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import GeoJSON from 'ol/format/GeoJSON.js';
import HeatmapLayer from 'ol/layer/Heatmap.js';
import Layer from 'ol/layer/Layer.js';
import Map from 'ol/Map.js';
import Source from 'ol/source/Source.js';
import VectorSource from 'ol/source/Vector.js';
import View from 'ol/View.js';
import {fromLonLat, toLonLat} from 'ol/proj.js';

const center = [-98.8, 37.9];
const key = 'Get your own API key at https://www.maptiler.com/cloud/';

const mbMap = new mapboxgl.Map({
  style: 'https://api.maptiler.com/maps/bright/style.json?key=' + key,
  attributionControl: false,
  boxZoom: false,
  center: center,
  container: 'map',
  doubleClickZoom: false,
  dragPan: false,
  dragRotate: false,
  interactive: false,
  keyboard: false,
  pitchWithRotate: false,
  scrollZoom: false,
  touchZoomRotate: false,
});

const mbLayer = new Layer({
  render: function (frameState) {
    const canvas = mbMap.getCanvas();
    const viewState = frameState.viewState;

    const visible = mbLayer.getVisible();
    canvas.style.display = visible ? 'block' : 'none';
    canvas.style.position = 'absolute';

    const opacity = mbLayer.getOpacity();
    canvas.style.opacity = opacity;

    // adjust view parameters in mapbox
    const rotation = viewState.rotation;
    mbMap.jumpTo({
      center: toLonLat(viewState.center),
      zoom: viewState.zoom - 1,
      bearing: (-rotation * 180) / Math.PI,
      animate: false,
    });

    // cancel the scheduled update & trigger synchronous redraw
    // see https://github.com/mapbox/mapbox-gl-js/issues/7893#issue-408992184
    // NOTE: THIS MIGHT BREAK IF UPDATING THE MAPBOX VERSION
    if (mbMap._frame) {
      mbMap._frame.cancel();
      mbMap._frame = null;
    }
    mbMap._render();

    return canvas;
  },
  source: new Source({
    attributions: [
      '<a href="https://www.maptiler.com/copyright/" target="_blank">© MapTiler</a>',
      '<a href="https://www.openstreetmap.org/copyright" target="_blank">© OpenStreetMap contributors</a>',
    ],
  }),
});

const cities = new HeatmapLayer({
  source: new VectorSource({
    url: 'data/geojson/world-cities.geojson',
    format: new GeoJSON(),
  }),
  weight: function (feature) {
    return feature.get('population') / 1e7;
  },
  radius: 15,
  blur: 15,
});

const map = new Map({
  target: 'map',
  view: new View({
    center: fromLonLat(center),
    zoom: 4,
  }),
  layers: [mbLayer, cities],
});

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>Mapbox-gl Layer</title>
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/mapbox-gl/1.13.0/mapbox-gl.css">
    <link rel="stylesheet" href="node_modules/ol/ol.css">
    <style>
      .map {
        width: 100%;
        height: 400px;
      }
      /* Reset font size changed by Mapbox CSS */
      .map {
        font-size: medium;
        font-family: 'Quattrocento Sans', sans-serif;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://cdn.jsdelivr.net/npm/elm-pep@1.0.6/dist/elm-pep.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/mapbox-gl/1.13.0/mapbox-gl.js"></script>
    <script type="module" src="main.js"></script>
  </body>
</html>