A canvas with a transparent background.
You can render Giro3D's scene on a transparent background, using the appropriate options in the Instance
constructor.
import colormap from 'colormap';
import { Color } from 'three';
import { MapControls } from 'three/examples/jsm/controls/MapControls.js';
import XYZ from 'ol/source/XYZ.js';
import Extent from '@giro3d/giro3d/core/geographic/Extent.js';
import Instance from '@giro3d/giro3d/core/Instance.js';
import ElevationLayer from '@giro3d/giro3d/core/layer/ElevationLayer.js';
import Map from '@giro3d/giro3d/entities/Map.js';
import GeoTIFFFormat from '@giro3d/giro3d/formats/GeoTIFFFormat.js';
import ColorMap, { ColorMapMode } from '@giro3d/giro3d/core/layer/ColorMap.js';
import TiledImageSource from '@giro3d/giro3d/sources/TiledImageSource.js';
import Inspector from '@giro3d/giro3d/gui/Inspector.js';
const x = -13602000;
const y = 5812000;
const halfWidth = 2500;
// Defines geographic extent: CRS, min/max X, min/max Y
const extent = new Extent('EPSG:3857', x - halfWidth, x + halfWidth, y - halfWidth, y + halfWidth);
const viewerDiv = document.getElementById('viewerDiv');
const instance = new Instance(viewerDiv, {
crs: extent.crs(),
renderer: {
clearColor: false,
},
});
const map = new Map('planar', {
extent,
hillshading: true,
doubleSided: true,
backgroundColor: 'white',
});
instance.add(map);
const source = new TiledImageSource({
source: new XYZ({
minZoom: 10,
maxZoom: 16,
url: 'https://3d.oslandia.com/dem/MtStHelens-tiles/{z}/{x}/{y}.tif',
}),
format: new GeoTIFFFormat(),
});
const floor = 1100;
const ceiling = 2500;
const values = colormap({ colormap: 'viridis', nshades: 256 });
const colors = values.map(v => new Color(v));
const dem = new ElevationLayer({
name: 'dem',
source,
extent,
colorMap: new ColorMap(colors, floor, ceiling, ColorMapMode.Elevation),
});
map.addLayer(dem);
instance.camera.camera3D.position.set(-13594700, 5819700, 7300);
const controls = new MapControls(instance.camera.camera3D, instance.domElement);
controls.target.set(-13603000, 5811000, 0);
instance.useTHREEControls(controls);
instance.notifyChange();
Inspector.attach(document.getElementById('panelDiv'), instance);
<!doctype html>
<html lang="en">
<head>
<title>Transparent canvas background</title>
<meta charset="UTF-8" />
<meta name="name" content="transparent_background" />
<meta name="description" content="A canvas with a transparent background." />
<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"
/>
<style>
#viewerDiv canvas {
background-image: linear-gradient(45deg, #aaaaaa 25%, transparent 25%),
linear-gradient(-45deg, #aaaaaa 25%, transparent 25%),
linear-gradient(45deg, transparent 75%, #aaaaaa 75%),
linear-gradient(-45deg, transparent 75%, #aaaaaa 75%);
background-size: 20px 20px;
background-position:
0 0,
0 10px,
10px -10px,
-10px 0px;
}
</style>
</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>
<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": "transparent_background",
"dependencies": {
"colormap": "^2.3.2",
"@giro3d/giro3d": "0.38.5"
},
"devDependencies": {
"vite": "^3.2.3"
},
"scripts": {
"start": "vite",
"build": "vite build"
}
}