WMS 512x256 Tiles

Example of a WMS layer with a custom grid with 512x256px tiles.

WMS can serve arbitrary tile sizes. This example uses a custom tile grid with non-square tiles.

main.js

import 'ol/ol.css';
import Map from 'ol/Map';
import OSM from 'ol/source/OSM';
import TileGrid from 'ol/tilegrid/TileGrid';
import TileLayer from 'ol/layer/Tile';
import TileWMS from 'ol/source/TileWMS';
import View from 'ol/View';
import {get as getProjection} from 'ol/proj';
import {getWidth} from 'ol/extent';

const projExtent = getProjection('EPSG:3857').getExtent();
const startResolution = getWidth(projExtent) / 256;
const resolutions = new Array(22);
for (let i = 0, ii = resolutions.length; i < ii; ++i) {
  resolutions[i] = startResolution / Math.pow(2, i);
}
const tileGrid = new TileGrid({
  extent: [-13884991, 2870341, -7455066, 6338219],
  resolutions: resolutions,
  tileSize: [512, 256],
});

const layers = [
  new TileLayer({
    source: new OSM(),
  }),
  new TileLayer({
    source: new TileWMS({
      url: 'https://ahocevar.com/geoserver/wms',
      params: {'LAYERS': 'topp:states', 'TILED': true},
      serverType: 'geoserver',
      tileGrid: tileGrid,
    }),
  }),
];
const map = new Map({
  layers: layers,
  target: 'map',
  view: new View({
    center: [-10997148, 4569099],
    zoom: 4,
  }),
});

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>WMS 512x256 Tiles</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>
    <script src="main.js"></script>
  </body>
</html>

package.json

{
  "name": "wms-custom-tilegrid-512x256",
  "dependencies": {
    "ol": "6.13.1-dev"
  },
  "devDependencies": {
    "parcel": "^2.0.0"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --public-url . index.html"
  }
}