Edit

Renders tiles with coordinates for debugging.

The black grid tiles are generated on the client with an HTML5 canvas. The displayed tile coordinates are the XYZ tile coordinates.

main.js
import Map from 'ol/Map.js';
import TileLayer from 'ol/layer/Tile.js';
import View from 'ol/View.js';
import {OSM, TileDebug} from 'ol/source.js';

const map = new Map({
  layers: [
    new TileLayer({
      source: new OSM(),
    }),
    new TileLayer({
      source: new TileDebug(),
    }),
  ],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 1,
  }),
});
index.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Canvas Tiles</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>

    <script type="module" src="main.js"></script>
  </body>
</html>
package.json
{
  "name": "canvas-tiles",
  "dependencies": {
    "ol": "8.2.0"
  },
  "devDependencies": {
    "vite": "^3.2.3"
  },
  "scripts": {
    "start": "vite",
    "build": "vite build"
  }
}