原文链接及内容

原文链接：https://openlayers.org/en/latest/examples/tile-transitions.html

运行界面

main.js代码如下：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
import Map from 'ol/Map.js';
import TileLayer from 'ol/layer/Tile.js';
import View from 'ol/View.js';
import XYZ from 'ol/source/XYZ.js';

const key = 'Get your own API key at https://www.maptiler.com/cloud/';
const attributions =
  '<a href="https://www.maptiler.com/copyright/" target="_blank">&copy; MapTiler</a> ' +
  '<a href="https://www.openstreetmap.org/copyright" target="_blank">&copy; OpenStreetMap contributors</a>';

const url = 'https://api.maptiler.com/maps/streets/{z}/{x}/{y}.png?key=' + key;

const withTransition = new TileLayer({
  source: new XYZ({url: url, tileSize: 512, attributions: attributions}),
});

const withoutTransition = new TileLayer({
  source: new XYZ({
    url: url,
    transition: 0,
    tileSize: 512,
    attributions: attributions,
  }),
  visible: false,
});

const map = new Map({
  layers: [withTransition, withoutTransition],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 2,
    maxZoom: 11,
  }),
});

document
  .getElementById('transition')
  .addEventListener('change', function (event) {
    const transition = event.target.checked;
    withTransition.setVisible(transition);
    withoutTransition.setVisible(!transition);
  });

界面布局文件index.html代码如下：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Tile Transitions</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>
    <label>
      render with an opacity transition
      <input id="transition" type="checkbox" checked>
    </label>
    <!-- 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 type="module" src="main.js"></script>
  </body>
</html>