Illustrates the reprojection of layers to match the coordinate system of the instance.

EPSG:2154
?

Type a projected CRS in the field below, then "Update" to create a scene with various layers. You can search for projection codes on epsg.io. Note: not all projections are supported.

RGF93 v1 / Lambert-93 -- France

France - onshore and offshore, mainland and Corsica (France métropolitaine including Corsica).

CRS
100% © Mapbox

A Layer can reproject the images produced by the ImageSource to conform to the CRS of the instance.

index.js
import XYZ from 'ol/source/XYZ.js';
import { Stroke, Style } from 'ol/style.js';
import { GeoJSON } from 'ol/format.js';

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 TiledImageSource from '@giro3d/giro3d/sources/TiledImageSource.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 VectorSource from '@giro3d/giro3d/sources/VectorSource.js';
import CogSource from '@giro3d/giro3d/sources/CogSource.js';
import { crsToUnit } from '@giro3d/giro3d/core/geographic/Coordinates.js';

/** @type {Instance} */
let instance;
/** @type {Inspector} */
let inspector;
/** @type {MapControls} */
let controls;
/** @type {Map} */
let map;

function addMapboxLayer(extent) {
    const apiKey =
        'pk.eyJ1IjoidG11Z3VldCIsImEiOiJjbGJ4dTNkOW0wYWx4M25ybWZ5YnpicHV6In0.KhDJ7W5N3d1z3ArrsDjX_A';

    // Adds a satellite basemap
    const tiledLayer = new ColorLayer({
        name: 'basemap',
        extent,
        showTileBorders: true,
        source: new TiledImageSource({
            source: new XYZ({
                url: `https://api.mapbox.com/v4/mapbox.satellite/{z}/{x}/{y}.webp?access_token=${apiKey}`,
                projection: 'EPSG:3857',
                crossOrigin: 'anonymous',
            }),
        }),
    });
    map.addLayer(tiledLayer).catch(e => console.error(e));
}

function addCogLayer() {
    const cogLayer = new ColorLayer({
        name: 'cog',
        showTileBorders: true,
        source: new CogSource({
            url: 'https://3d.oslandia.com/giro3d/rasters/TCI.tif',
            crs: 'EPSG:3857',
        }),
    });
    map.addLayer(cogLayer).catch(e => console.error(e));
}

function addVectorLayer() {
    const outlineStyle = new Style({
        stroke: new Stroke({ color: 'red', width: 2 }),
    });

    // Display the countries boundaries.
    const boundaries = new ColorLayer({
        name: 'boundaries',
        source: new VectorSource({
            format: new GeoJSON(),
            data: 'https://3d.oslandia.com/giro3d/vectors/countries.geojson',
            style: outlineStyle,
            dataProjection: 'EPSG:4326',
        }),
    });

    map.addLayer(boundaries).catch(e => console.error(e));
}

function createScene(crs, crsDef, extent) {
    if (instance) {
        map.getLayers().forEach(l => l.dispose());
        controls.dispose();
        inspector.detach();
        instance.dispose();
    }

    Instance.registerCRS(crs, crsDef);

    // `viewerDiv` will contain Giro3D' rendering area (the canvas element)
    const viewerDiv = document.getElementById('viewerDiv');

    // Creates a Giro3D instance
    instance = new Instance(viewerDiv, { crs, renderer: { clearColor: 'grey' } });

    // Adds the map that will contain the layers.
    map = new Map('map', { extent, hillshading: true });

    instance.add(map);

    // Add a bunch of layers
    addMapboxLayer(extent);

    addCogLayer();

    addVectorLayer();

    // Sets the camera position
    const center = extent.centerAsVector3();
    instance.camera.camera3D.position.set(center.x, center.y - 1, extent.dimensions().y * 2);

    // Creates controls
    controls = new MapControls(instance.camera.camera3D, viewerDiv);

    // Then looks at extent's center
    controls.target = center;
    controls.saveState();

    controls.enableDamping = true;
    controls.dampingFactor = 0.2;
    controls.maxPolarAngle = Math.PI / 2.3;

    instance.useTHREEControls(controls);

    inspector = Inspector.attach(document.getElementById('panelDiv'), instance);

}

async function fetchCrsBbox(crs) {
    const code = crs.split(':')[1];
    const url = `https://epsg.io/${code}.json?download=1`;
    const res = await fetch(url, { mode: 'cors' });
    const json = await res.json();

    const bbox = json.bbox;
    const south = Number.parseFloat(bbox.south_latitude);
    const north = Number.parseFloat(bbox.north_latitude);
    const west = Number.parseFloat(bbox.west_longitude);
    const east = Number.parseFloat(bbox.east_longitude);

    const wgs84Extent = new Extent('EPSG:4326', {
        west,
        east,
        north,
        south,
    });

    document.getElementById('currentCrsCode').innerText = crs;
    document.getElementById('currentCrsName').innerText = json.name;
    document.getElementById('currentCrsArea').innerText = json.area;

    if (crsToUnit(crs) === undefined) {
        // Unsupported projection
        throw new Error('unsupported projection (invalid units)');
    } else {
        return wgs84Extent.as(crs);
    }
}

async function fetchCrsDefinition(crs) {
    const code = crs.split(':')[1];
    const url = `https://epsg.io/${code}.proj4?download=1`;
    const res = await fetch(url, { mode: 'cors' });
    const def = await res.text();

    Instance.registerCRS(crs, def);

    return def;
}

async function initialize(crs) {
    try {
        const def = await fetchCrsDefinition(crs);
        const extent = await fetchCrsBbox(crs);
        const proj = crs;
        const error = document.getElementById('errorMessage');
        error.style.display = 'none';

        createScene(proj, def, extent);
    } catch (e) {
        const msg = e.message;
        const error = document.getElementById('errorMessage');
        error.innerText = msg;
        error.style.display = 'block';
    }
}

/** @type {HTMLButtonElement} */
const button = document.getElementById('createSceneBtn');

button.onclick = () => {
    /** @type {HTMLInputElement} */
    const epsgCodeElt = document.getElementById('epsgCode');

    const content = epsgCodeElt.value;

    if (content) {
        initialize(content);
    }
};

initialize('EPSG:2154');
index.html
<!doctype html>
<html lang="en">
    <head>
        <title>Layer reprojection</title>
        <meta charset="UTF-8" />
        <meta name="name" content="layer_reprojection" />
        <meta name="description" content="Illustrates the reprojection of layers to match the coordinate system of the instance." />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />

        <link rel="icon" href="https://giro3d.org/images/favicon.svg" />
        <link href="https://giro3d.org/assets/bootstrap-custom.css" rel="stylesheet" />
        <script src="https://giro3d.org/assets/bootstrap.bundle.min.js"></script>
        <link
            rel="stylesheet"
            type="text/css"
            href="https://giro3d.org/latest/css/example.css"
        />

        
    </head>

    <body>
        <div id="viewerDiv" class="m-0 p-0 w-100 h-100"></div>
        <div id="panelDiv" class="position-absolute top-0 start-0 mh-100 overflow-auto"></div>

        <div class="side-pane-with-status-bar" style="width: 22rem">
            <div class="mh-100 overflow-y-auto">
                <div class="card" id="currentCrsSection">
                    <!-- CRS code -->
                    <div class="card-header" id="currentCrsCode">EPSG:2154</div>

                    <!-- tooltip -->
                    <span
                        class="badge bg-secondary position-absolute top-0 end-0 m-2"
                        data-bs-toggle="popover"
                        data-bs-content="help"
                        >?</span
                    >
                    <p class="card-text d-none" id="help">
                        Type a projected CRS in the field below, then "Update" to create a scene with
                        various layers. You can search for projection codes on
                        <a target="_blank" href="https://epsg.io/?q=epsg">epsg.io</a>. <b>Note:</b> not all
                        projections are supported.
                    </p>

                    <!-- CRS name and area -->
                    <div class="card-body">
                        <h5 class="card-title" id="currentCrsName">RGF93 v1 / Lambert-93 -- France</h5>
                        <p class="card-text" id="currentCrsArea">
                            France - onshore and offshore, mainland and Corsica (France métropolitaine
                            including Corsica).
                        </p>
                    </div>
                </div>

                <!-- CRS selector -->
                <div class="input-group mt-3">
                    <span class="input-group-text" id="epsgCodeLabel">CRS</span>
                    <input
                        type="text"
                        class="form-control"
                        id="epsgCode"
                        placeholder="EPSG code (e.g EPSG:3857)"
                        value="EPSG:2154"
                        aria-label="EpsgCode"
                        aria-describedby="epsgCodeLabel"
                    />
                    <button class="input-group-text btn btn-primary" id="createSceneBtn">Update</button>
                </div>

                <!-- Error message -->
                <div class="alert alert-danger mt-3" id="errorMessage" style="display: none" role="alert">
                    A simple primary alert—check it out!
                </div>
            </div>
        </div>

        <script type="module" src="index.js"></script>
        <script>
            /* activate popovers */
            const popoverTriggerList = [].slice.call(
                document.querySelectorAll('[data-bs-toggle="popover"]'),
            );
            popoverTriggerList.map(
                // bootstrap is used as script in the template, disable warning about undef
                // eslint-disable-next-line no-undef
                popoverTriggerEl =>
                    new bootstrap.Popover(popoverTriggerEl, {
                        trigger: 'hover',
                        placement: 'left',
                        content: document.getElementById(
                            popoverTriggerEl.getAttribute('data-bs-content'),
                        ).innerHTML,
                        html: true,
                    }),
            );
        </script>
    </body>
</html>
package.json
{
    "name": "layer_reprojection",
    "dependencies": {
        "@giro3d/giro3d": "0.37.2"
    },
    "devDependencies": {
        "vite": "^3.2.3"
    },
    "scripts": {
        "start": "vite",
        "build": "vite build"
    }
}