Generate and add a missing icon to the map
Dynamically generate a missing icon at runtime and add it to the map.
<!DOCTYPE html><html><head><meta charset="utf-8" /><title>Generate and add a missing icon to the map</title><meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" /><script src="https://cdn.jsdelivr.net/npm/@goongmaps/goong-js@1.0.9/dist/goong-js.js"></script><link href="https://cdn.jsdelivr.net/npm/@goongmaps/goong-js@1.0.9/dist/goong-js.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>goongjs.accessToken = '8qzxZAuxcsctSlmOszInchP1A5GrmRBHJwCBCjO6';var map = new goongjs.Map({container: 'map',style: 'https://tiles.goong.io/assets/goong_map_web.json'}); map.on('styleimagemissing', function (e) {var id = e.id; // id of the missing image // check if this missing icon is one this function can generatevar prefix = 'square-rgb-';if (id.indexOf(prefix) !== 0) return; // extract the color from the idvar rgb = id.replace(prefix, '').split(',').map(Number); var width = 64; // The image will be 64 pixels squarevar 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] = rgb[0]; // reddata[offset + 1] = rgb[1]; // greendata[offset + 2] = rgb[2]; // bluedata[offset + 3] = 255; // alpha}} map.addImage(id, { width: width, height: width, data: data });}); map.on('load', function () {map.addSource('points', {'type': 'geojson','data': {'type': 'FeatureCollection','features': [{'type': 'Feature','geometry': {'type': 'Point','coordinates': [0, 0]},'properties': {'color': '255,0,0'}},{'type': 'Feature','geometry': {'type': 'Point','coordinates': [50, 0]},'properties': {'color': '255,209,28'}},{'type': 'Feature','geometry': {'type': 'Point','coordinates': [-50, 0]},'properties': {'color': '242,127,32'}}]}}); map.addLayer({'id': 'points','type': 'symbol','source': 'points','layout': {'icon-image': ['concat', 'square-rgb-', ['get', 'color']]}});});</script> </body></html>