Display buildings in 3D | TrackAsia GL JS Docs

Use extrusions to display buildings' height in 3D.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Display buildings in 3D</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" />
<script src="https://unpkg.com/trackasia-gl@1.0.5/dist/trackasia-gl.js"></script>
<link href="https://unpkg.com/trackasia-gl@1.0.5/dist/trackasia-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 trackasiagl.Map({
style: 'https://maps.track-asia.com/styles/v1/streets.json?key=public_key',
center: {"lat":10.762622,"lng":106.660172},
zoom: 16.5,
pitch: 45,
bearing: -17.6,
container: 'map',
antialias: true
});
 
// The 'building' layer in the streets vector source contains building-height
// data from OpenStreetMap.
map.on('load', function () {
// Insert the layer beneath any symbol layer.
var layers = map.getStyle().layers;
 
var labelLayerId;
for (var i = 0; i < layers.length; i++) {
if (layers[i].type === 'symbol' && layers[i].layout['text-field']) {
labelLayerId = layers[i].id;
break;
}
}
 
map.addLayer(
{
'id': '3d-buildings',
'source': 'composite',
'source-layer': 'building',
'filter': ['==', 'extrude', 'true'],
'type': 'fill-extrusion',
'minzoom': 13,
'paint': {
'fill-extrusion-color': '#004899',
 
// use an 'interpolate' expression to add a smooth transition effect to the
// buildings as the user zooms in
'fill-extrusion-height': [
'interpolate',
['linear'],
['zoom'],
15,
0,
15.05,
['get', 'height']
],
'fill-extrusion-base': [
'interpolate',
['linear'],
['zoom'],
15,
0,
15.05,
['get', 'min_height']
],
'fill-extrusion-opacity': 0.6
}
},
labelLayerId
);
});
</script>
 
</body>
</html>