Tile Transitions

render with an opacity transition

Custom configuration for opacity transitions on tiles.

By default tiles are rendered with an opacity transition - fading in over 250 ms. To disable this behavior, set the transition option of the tile source to 0.

main.js

import 'ol/ol.css';
import Map from 'ol/Map';
import TileLayer from 'ol/layer/Tile';
import View from 'ol/View';
import XYZ from 'ol/source/XYZ';

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);
  });

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Tile Transitions</title>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://unpkg.com/elm-pep@1.0.6/dist/elm-pep.js"></script>
    <!-- The lines below are only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v3/polyfill.min.js?features=fetch,requestAnimationFrame,Element.prototype.classList,TextDecoder"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/core-js/3.18.3/minified.js"></script>
    <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>
    <script src="main.js"></script>
  </body>
</html>

package.json

{
  "name": "tile-transitions",
  "dependencies": {
    "ol": "6.13.1-dev"
  },
  "devDependencies": {
    "parcel": "^2.0.0"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --public-url . index.html"
  }
}