Illustrates the automatic reprojection of vectors to match the instance's CRS.
Display a map in EPGS:2154 with GeoJSON features displayed as meshes in various CRS, showing reprojection capabilities of FeatureCollection.
import GeoJSON from 'ol/format/GeoJSON.js';
import VectorSource from 'ol/source/Vector.js';
import { createXYZ } from 'ol/tilegrid.js';
import { tile } from 'ol/loadingstrategy.js';
import { Color, Vector3 } from 'three';
import { MapControls } from 'three/examples/jsm/controls/MapControls.js';
import Instance from '@giro3d/giro3d/core/Instance.js';
import Extent from '@giro3d/giro3d/core/geographic/Extent.js';
import Inspector from '@giro3d/giro3d/gui/Inspector.js';
import FeatureCollection from '@giro3d/giro3d/entities/FeatureCollection.js';
import Coordinates from '@giro3d/giro3d/core/geographic/Coordinates';
import { MathUtils } from 'three/src/math/MathUtils.js';
// Defines projection that we will use (taken from https://epsg.io/2154, Proj4js section)
Instance.registerCRS(
'EPSG:2154',
'+proj=lcc +lat_0=46.5 +lon_0=3 +lat_1=49 +lat_2=44 +x_0=700000 +y_0=6600000 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs +type=crs',
);
const viewerDiv = document.getElementById('viewerDiv');
const extent = new Extent('EPSG:2154', -111629.52, 1275028.84, 5976033.79, 7230161.64);
const instance = new Instance(viewerDiv, { crs: extent.crs() });
// This is a geojson with the default crs EPSG:4326
const arrondissementSource = new VectorSource({
format: new GeoJSON(),
url: './data/paris_arrondissements.geojson',
});
function getHue(area) {
const minArea = 991153;
const maxArea = 16372542;
const hue = MathUtils.mapLinear(area, minArea, maxArea, 0.2, 0.8);
return MathUtils.clamp(hue, 0, 1);
}
// feat get automatically reprojected
const arrondissements = new FeatureCollection('arrondissements', {
source: arrondissementSource,
extent,
ignoreZ: true,
minLevel: 0,
maxLevel: 0,
style: feature => {
// The style depends on the polygon's area
const t = getHue(feature.get('surface'));
const highlight = feature.get('highlight');
const brightness = highlight ? 1 : 0.7;
const color = new Color().setHSL(0, t, brightness * t, 'srgb');
return {
fill: {
color,
depthTest: false,
renderOrder: 1,
},
stroke: highlight
? {
color: 'white',
depthTest: false,
renderOrder: 2,
}
: null,
};
},
});
instance.add(arrondissements);
// another geojson in 3857 (openlayers, and thus Giro3D, supports the non-official yet supported
// everywhere way of specifying the crs in the geojson file itself)
const perimeterqaaSource = new VectorSource({
format: new GeoJSON(),
url: './data/perimetreqaa.geojson',
});
const perimeterqaa = new FeatureCollection('perimeterqaa', {
source: perimeterqaaSource,
extent,
ignoreZ: true,
minLevel: 0,
maxLevel: 0,
style: feature => {
const highlight = feature.get('highlight');
return {
fill: {
color: highlight ? '#5d914d' : '#41822d',
depthTest: false,
opacity: 0.7,
renderOrder: 3,
},
stroke: {
color: '#85f516',
lineWidth: highlight ? 4 : 1,
depthTest: false,
renderOrder: 4,
},
};
},
});
instance.add(perimeterqaa);
// a WFS source in 3857
const bdTopoSource = new VectorSource({
format: new GeoJSON(),
url: function url(bbox) {
return `${
'https://data.geopf.fr/wfs/ows' +
'?SERVICE=WFS' +
'&VERSION=2.0.0' +
'&request=GetFeature' +
'&typename=BDTOPO_V3:batiment' +
'&outputFormat=application/json' +
'&SRSNAME=EPSG:3857' +
'&startIndex=0' +
'&bbox='
}${bbox.join(',')},EPSG:3857`;
},
strategy: tile(createXYZ({ tileSize: 512 })),
});
const feat = new FeatureCollection('buildings', {
source: bdTopoSource,
// we specify that FeatureCollection should reproject the features before displaying them
dataProjection: 'EPSG:3857',
// We are working on a flat, 2D scene, so we must ignore the Z coordinate of features, if any.
ignoreZ: true,
extent,
style: feature => {
const properties = feature.getProperties();
const highlighted = properties.highlight;
let color = '#FFFFFF';
if (highlighted) {
color = 'cyan';
} else {
if (properties.usage_1 === 'Résidentiel') {
color = '#9d9484';
} else if (properties.usage_1 === 'Commercial et services') {
color = '#b0ffa7';
}
}
return {
fill: {
color,
depthTest: false,
renderOrder: 5,
},
stroke: {
color: 'black',
renderOrder: 6,
depthTest: false,
},
};
},
minLevel: 11,
maxLevel: 11,
});
instance.add(feat);
// place camera above paris
const position = new Coordinates('EPSG:2154', 652212.5, 6860754.1, 27717.3);
const lookAtCoords = new Coordinates('EPSG:2154', 652338.3, 6862087.1, 200);
const lookAt = new Vector3(lookAtCoords.x, lookAtCoords.y, lookAtCoords.z);
instance.camera.camera3D.position.set(position.x, position.y, position.z);
instance.camera.camera3D.lookAt(lookAt);
// Notify Giro3D we've changed the three.js camera position directly
instance.notifyChange(instance.camera.camera3D);
// Creates controls
const controls = new MapControls(instance.camera.camera3D, instance.domElement);
controls.enableDamping = true;
controls.dampingFactor = 0.2;
// you need to use these 2 lines each time you change the camera lookAt or position programatically
controls.target.copy(lookAt);
controls.saveState();
instance.useTHREEControls(controls);
// information on click
const resultTable = document.getElementById('results');
let previousObjects = [];
const objectsToUpdate = [];
function createResultTable(values) {
resultTable.innerHTML = '';
for (const value of values) {
const child = document.createElement('li');
// child.classList.add('list-group-item');
child.innerText = value;
resultTable.appendChild(child);
}
}
function pick(e) {
instance.notifyChange();
// pick objects
const pickedObjects = instance.pickObjectsAt(e, {
radius: 2,
where: [arrondissements, perimeterqaa],
});
// Reset highlights
previousObjects.forEach(o => o.userData.feature.set('highlight', false));
const tableValues = [];
if (pickedObjects.length !== 0) {
resultTable.innerHTML = '';
for (const p of pickedObjects) {
const obj = p.object;
const feature = obj.userData.feature;
const entity = obj.userData.parentEntity;
objectsToUpdate.push(obj);
if (entity === arrondissements) {
tableValues.push(feature.get('l_ar'));
}
if (entity === perimeterqaa) {
tableValues.push('Improved Accessibility Zone');
}
// highlight it
feature.set('highlight', true);
}
}
createResultTable(tableValues);
instance.notifyChange([...previousObjects, ...objectsToUpdate]);
previousObjects = [...objectsToUpdate];
objectsToUpdate.length = 0;
}
instance.domElement.addEventListener('mousemove', pick);
// Bind events
Inspector.attach(document.getElementById('panelDiv'), instance);
<!doctype html>
<html lang="en">
<head>
<title>Reprojection of features as mesh</title>
<meta charset="UTF-8" />
<meta name="name" content="feature_collection_reprojection" />
<meta name="description" content="Illustrates the automatic reprojection of vectors to match the instance's CRS." />
<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="min-height: 9rem">
<div class="card">
<h5 class="card-header">Information</h5>
<!-- tooltip -->
<span
class="badge bg-secondary position-absolute top-0 end-0 m-2"
data-bs-toggle="popover"
data-bs-content="tooltip"
>?</span
>
<p class="card-text d-none" id="tooltip">Some informations embedded in the GeoJSON</p>
<div class="card-body pe-none">
<!-- Result table -->
<ul style="width: 12rem" id="results"></ul>
</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>
{
"name": "feature_collection_reprojection",
"dependencies": {
"@giro3d/giro3d": "0.38.5"
},
"devDependencies": {
"vite": "^3.2.3"
},
"scripts": {
"start": "vite",
"build": "vite build"
}
}