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, segments: 128, 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>
  <meta charset="UTF-8">
  <title>Giro3D - Layer reprojection</title>
  <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-T3c6CoIi6uLrA9TneNEoa7RxnatzjcDSCmG1MXxSR1GAsXEV/Dwwykc2MPK8M2HN" crossorigin="anonymous">
  <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap-icons@1.11.3/font/bootstrap-icons.min.css">
  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.min.js" integrity="sha384-C6RzsynM9kWDrMNeT87bh95OGNyZPhcTNXj1NW7RuBCsyN/o0jlpcV8Qyq46cDfL" crossorigin="anonymous"></script>
  <style>
    body {
      padding: 0;
      margin: 0;
      width: 100vw;
      height: 100vh;
    }

    #viewerDiv {
      width: 100%;
      height: 100%;
    }

    #panelDiv {
      position: absolute;
      top: 0;
      left: 0;
    }
    
  </style>
</head>

<body>
  <div id="viewerDiv"></div>
  <div id="panelDiv"></div>
  <div class="m-3 position-absolute top-0 end-0" style="width: 22rem">
    <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>

  <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": "0.35.0"
  },
  "devDependencies": {
    "vite": "^3.2.3"
  },
  "scripts": {
    "start": "vite",
    "build": "vite build"
  }
}