Display multiple maps that share the same layer.

100% Map style by Stamen Design, © OpenStreetMap contributors

import { MapControls } from 'three/examples/jsm/controls/MapControls.js';
import Extent from '@giro3d/giro3d/core/geographic/Extent.js';
import Instance from '@giro3d/giro3d/core/Instance.js';
import ColorLayer from '@giro3d/giro3d/core/layer/ColorLayer.js';
import Map from '@giro3d/giro3d/entities/Map.js';
import Inspector from '@giro3d/giro3d/gui/Inspector.js';
import StadiaMaps from 'ol/source/StadiaMaps.js';
import TiledImageSource from '@giro3d/giro3d/sources/TiledImageSource.js';
import StatusBar from './widgets/StatusBar.js';

// Defines geographic extent: CRS, min/max X, min/max Y
const extent = new Extent(
    'EPSG:3857',
    -20037508.342789244, 20037508.342789244,
    -20037508.342789244, 20037508.342789244,
);

// `viewerDiv` will contain giro3d' rendering area (the canvas element)
const viewerDiv = document.getElementById('viewerDiv');

// Creates a giro3d instance
const instance = new Instance(viewerDiv, {
    crs: extent.crs(),
    renderer: {
        clearColor: 0x0a3b59,
    },
});

// Adds an TMS imagery layer
const layer = new ColorLayer(
    'osm',
    {
        source: new TiledImageSource({ source: new StadiaMaps({ layer: 'stamen_watercolor', wrapX: false }) }),
    },
);

let index = 0;
const promises = [];
for (const ex of extent.split(8, 8)) {
    const mapExtent = ex.withRelativeMargin(-0.05);
    // Creates a map that will contain the layer
    const map = new Map(`planar ${index++}`, { extent: mapExtent });

    instance.add(map);

    const promise = map.addLayer(layer).catch(e => console.error(e));
    promises.push(promise);
}

Promise.allSettled(promises).then(() => {
    // Instanciates camera
    instance.camera.camera3D.position.set(0, 0, 25000000);

    // Instanciates controls
    const controls = new MapControls(instance.camera.camera3D, instance.domElement);

    instance.useTHREEControls(controls);

    Inspector.attach(document.getElementById('panelDiv'), instance);
    StatusBar.bind(instance);
});