All docsMapbox GL JSExamplesStyle symbols based on pitch

Style symbols based on pitch

This example uses the ['pitch'] expression to add in leader lines to labels after a certain pitch threshold is crossed. This is achieved by adding two different layers and setting complementary pitch based filter conditions on them.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Style symbols based on pitch</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no">
<link href="https://api.mapbox.com/mapbox-gl-js/v2.6.0/mapbox-gl.css" rel="stylesheet">
<script src="https://api.mapbox.com/mapbox-gl-js/v2.6.0/mapbox-gl.js"></script>
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
<script>
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';
const map = new mapboxgl.Map({
container: 'map',
zoom: 13.5,
pitch: 85,
bearing: 70,
center: [-119.53543366513888, 37.74467518164313],
style: 'mapbox://styles/mapbox-map-design/ckvinefga12gk14o2zxwo0721'
});
map.on('load', () => {
// Extract JSON representation of an existing layer
const layer = map
.getStyle()
.layers.find((layer) => layer.id === 'natural-point-label');
// Add in a pitch condition to the existing layers filter
// so that it only renders when the pitch is low
const lowPitchFilter = ['all', layer.filter, ['<', ['pitch'], 60]];
map.setFilter('natural-point-label', lowPitchFilter);
// Add in styling for leader lines into the layer
layer.id = 'natural-point-label-elevated';
// Add a leader line using `icon-image`
layer.layout['icon-image'] = 'leader_line';
layer.layout['icon-anchor'] = 'bottom';
// Elevate the text using text-offset
layer.layout['text-offset'] = [0, -12.5];
// Set the filter to only render at high pitch
const highPitchFilter = ['all', layer.filter, ['>=', ['pitch'], 60]];
layer.filter = highPitchFilter;
// Add in a new layer with the updated styling
map.addLayer(layer, 'natural-point-label');
});
</script>
</body>
</html>