This example uses OpenLayers v10.9.0. The latest is v.
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#### Sphere Mollweide

graticule 3 Mollweide 1 projection 14 proj4js 6

#####

Example of a Sphere Mollweide map with a Graticule layer.

Example of a Sphere Mollweide map with a Graticule layer.

##### main.js

    import Map from 'ol/Map.js';
    import View from 'ol/View.js';
    import GeoJSON from 'ol/format/GeoJSON.js';
    import Graticule from 'ol/layer/Graticule.js';
    import VectorLayer from 'ol/layer/Vector.js';
    import Projection from 'ol/proj/Projection.js';
    import {register} from 'ol/proj/proj4.js';
    import VectorSource from 'ol/source/Vector.js';
    import proj4 from 'proj4';

    proj4.defs(
      'ESRI:53009',
      '+proj=moll +lon_0=0 +x_0=0 +y_0=0 +a=6371000 ' +
        '+b=6371000 +units=m +no_defs',
    );
    register(proj4);

    // Configure the Sphere Mollweide projection object with an extent,
    // and a world extent. These are required for the Graticule.
    const sphereMollweideProjection = new Projection({
      code: 'ESRI:53009',
      extent: [
        -18019909.21177587, -9009954.605703328, 18019909.21177587,
        9009954.605703328,
      ],
      worldExtent: [-179, -89.99, 179, 89.99],
    });

    const map = new Map({
      keyboardEventTarget: document,
      layers: [
        new VectorLayer({
          source: new VectorSource({
            url: 'https://openlayers.org/data/vector/ecoregions.json',
            format: new GeoJSON(),
          }),
          style: {
            'fill-color': ['string', ['get', 'COLOR_BIO'], '#eee'],
          },
        }),
        new Graticule(),
      ],
      target: 'map',
      view: new View({
        center: [0, 0],
        projection: sphereMollweideProjection,
        zoom: 2,
      }),
    });

##### index.html

    <!DOCTYPE html>
    <html lang="en">
      <head>
        <meta charset="UTF-8">
        <title>Sphere Mollweide</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": "sphere-mollweide",
      "dependencies": {
        "ol": "10.9.0",
        "proj4": "2.20.8"
      },
      "devDependencies": {
        "vite": "^3.2.3"
      },
      "scripts": {
        "start": "vite",
        "build": "vite build"
      }
    }