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Demonstrates displaying IGN (France) WMTS layers.

In this example an IGN WMTS layer is displayed. For more information on IGN's WMTS service see the IGN Géoportail API web page and Documentation de l’offre de données et services de l’IGN (french).

main.js
import 'ol/ol.css';
import Map from 'ol/Map';
import TileLayer from 'ol/layer/Tile';
import View from 'ol/View';
import WMTS from 'ol/source/WMTS';
import WMTSTileGrid from 'ol/tilegrid/WMTS';
import {fromLonLat, get as getProjection} from 'ol/proj';
import {getWidth} from 'ol/extent';

const map = new Map({
  target: 'map',
  view: new View({
    zoom: 5,
    center: fromLonLat([5, 45]),
  }),
});

const resolutions = [];
const matrixIds = [];
const proj3857 = getProjection('EPSG:3857');
const maxResolution = getWidth(proj3857.getExtent()) / 256;

for (let i = 0; i < 20; i++) {
  matrixIds[i] = i.toString();
  resolutions[i] = maxResolution / Math.pow(2, i);
}

const tileGrid = new WMTSTileGrid({
  origin: [-20037508, 20037508],
  resolutions: resolutions,
  matrixIds: matrixIds,
});

// For more information about the IGN API key see
// https://geoservices.ign.fr/blog/2021/01/29/Maj_Cles_Geoservices.html

const ign_source = new WMTS({
  url: 'https://wxs.ign.fr/choisirgeoportail/geoportail/wmts',
  layer: 'GEOGRAPHICALGRIDSYSTEMS.PLANIGNV2',
  matrixSet: 'PM',
  format: 'image/png',
  projection: 'EPSG:3857',
  tileGrid: tileGrid,
  style: 'normal',
  attributions:
    '<a href="https://www.ign.fr/" target="_blank">' +
    '<img src="https://wxs.ign.fr/static/logos/IGN/IGN.gif" title="Institut national de l\'' +
    'information géographique et forestière" alt="IGN"></a>',
});

const ign = new TileLayer({
  source: ign_source,
});

map.addLayer(ign);
index.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>IGN WMTS</title>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://unpkg.com/[email protected]/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>
    <script src="main.js"></script>
  </body>
</html>
package.json
{
  "name": "wmts-ign",
  "dependencies": {
    "ol": "6.14.1"
  },
  "devDependencies": {
    "parcel": "^2.0.0"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --public-url . index.html"
  }
}