Add a generated icon to the map | UNL Map JS Docs

Add an icon to the map that was generated at runtime.

Note

If you want to test this example, edit it in JSFiddle or CodePen and replace the "YOUR-OWN-API-KEY" and "YOUR-OWN-VPM-ID" placeholders with your actual api key and vpm id.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Add a generated icon to the map</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" />
<script src="https://unpkg.com/unl-map-js@0.1.5/lib/unl-map-js.js"></script>
<link href="https://unpkg.com/unl-map-js@0.1.5/lib/unl-map-js.css" rel="stylesheet" />
<link
href="https://unpkg.com/maplibre-gl@2.1.9/dist/maplibre-gl.css"
rel="stylesheet"
/>
<style>
	body { margin: 0; padding: 0; }
	#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
 
<script>
var map = new UnlSdk.Map({
container: "map",
apiKey: "YOUR-OWN-API-KEY",
vpmId: "YOUR-OWN-VPM-ID",
});
 
map.on("load", function () {
var width = 64; // The image will be 64 pixels square
var bytesPerPixel = 4; // Each pixel is represented by 4 bytes: red, green, blue, and alpha.
var data = new Uint8Array(width * width * bytesPerPixel);
 
for (var x = 0; x < width; x++) {
for (var y = 0; y < width; y++) {
var offset = (y * width + x) * bytesPerPixel;
data[offset + 0] = (y / width) * 255; // red
data[offset + 1] = (x / width) * 255; // green
data[offset + 2] = 128; // blue
data[offset + 3] = 255; // alpha
}
}
 
map.addImage("gradient", { width: width, height: width, data: data });
 
map.addSource("point", {
type: "geojson",
data: {
type: "FeatureCollection",
features: [
{
type: "Feature",
geometry: {
type: "Point",
coordinates: [0, 0],
},
},
],
},
});
map.addLayer({
id: "points",
type: "symbol",
source: "point",
layout: {
"icon-image": "gradient",
},
});
});
</script>
 
</body>
</html>