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Create and Style Clusters

Create and Style Clusters

Cluster nearby points using GeoJSON clustering and style by cluster size.

const API_KEY = 'toursprung';

    const map = new maptoolkit.Map({
        container: 'map',
        style: `https://static.maptoolkit.net/styles/toursprung/terrain.json?api_key=${API_KEY}`,
        center: [-103.59179687498357, 40.66995747013945],
        zoom: 3,
        attributionControl: { compact: false }
    });

    map.addControl(new maptoolkit.NavigationControl(), 'top-right');

    map.on('load', () => {
        map.addSource('earthquakes', {
            type: 'geojson',
            data: 'https://maplibre.org/maplibre-gl-js/docs/assets/earthquakes.geojson',
            cluster: true,
            clusterMaxZoom: 14, // Max zoom to cluster points on
            clusterRadius: 50   // Radius of each cluster when clustering points (defaults to 50)
        });

        map.addLayer({
            id: 'clusters',
            type: 'circle',
            source: 'earthquakes',
            filter: ['has', 'point_count'],
            paint: {
                // Use step expressions (https://maplibre.org/maplibre-gl-js/docs/overview/expressions/#step)
                // with three steps to implement three types of circles:
                //   * Blue, 20px circles when point count is less than 100
                //   * Yellow, 30px circles when point count is between 100 and 750
                //   * Pink, 40px circles when point count is greater than or equal to 750
                'circle-color': [
                    'step', ['get', 'point_count'],
                    '#51bbd6', 100,
                    '#f1f075', 750,
                    '#f28cb1'
                ],
                'circle-radius': [
                    'step', ['get', 'point_count'],
                    20, 100,
                    30, 750,
                    40
                ]
            }
        });

        map.addLayer({
            id: 'cluster-count',
            type: 'symbol',
            source: 'earthquakes',
            filter: ['has', 'point_count'],
            layout: {
                'text-field': '{point_count_abbreviated}',
                'text-size': 12
            }
        });

        map.addLayer({
            id: 'unclustered-point',
            type: 'circle',
            source: 'earthquakes',
            filter: ['!', ['has', 'point_count']],
            paint: {
                'circle-color': '#11b4da',
                'circle-radius': 4,
                'circle-stroke-width': 1,
                'circle-stroke-color': '#fff'
            }
        });

        // Inspect a cluster on click
        map.on('click', 'clusters', async (e) => {
            const features = map.queryRenderedFeatures(e.point, { layers: ['clusters'] });
            const clusterId = features[0].properties.cluster_id;
            const zoom = await map.getSource('earthquakes').getClusterExpansionZoom(clusterId);
            map.easeTo({ center: features[0].geometry.coordinates, zoom });
        });

        map.on('mouseenter', 'clusters', () => { map.getCanvas().style.cursor = 'pointer'; });
        map.on('mouseleave', 'clusters', () => { map.getCanvas().style.cursor = ''; });
    });
<!DOCTYPE html>
<html lang="en">
<head>
    <title>Create and Style Clusters – Maptoolkit Maps JS</title>
    <meta property="og:description" content="Cluster nearby points using GeoJSON clustering and style by cluster size." />
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <script src="https://unpkg.com/@maptoolkit/maps@11.0.0-beta.2/dist/maptoolkit.js"></script>
    <link rel="stylesheet" href="https://unpkg.com/@maptoolkit/maps@11.0.0-beta.2/dist/maptoolkit.css" />
    <style>
        html, body { width: 100%; height: 100%; margin: 0; padding: 0; }
        #map { width: 100%; height: 100%; }
    </style>
</head>
<body>
<div id="map"></div>
<script>
    const API_KEY = 'toursprung';

    const map = new maptoolkit.Map({
        container: 'map',
        style: `https://static.maptoolkit.net/styles/toursprung/terrain.json?api_key=${API_KEY}`,
        center: [-103.59179687498357, 40.66995747013945],
        zoom: 3,
        attributionControl: { compact: false }
    });

    map.addControl(new maptoolkit.NavigationControl(), 'top-right');

    map.on('load', () => {
        map.addSource('earthquakes', {
            type: 'geojson',
            data: 'https://maplibre.org/maplibre-gl-js/docs/assets/earthquakes.geojson',
            cluster: true,
            clusterMaxZoom: 14, // Max zoom to cluster points on
            clusterRadius: 50   // Radius of each cluster when clustering points (defaults to 50)
        });

        map.addLayer({
            id: 'clusters',
            type: 'circle',
            source: 'earthquakes',
            filter: ['has', 'point_count'],
            paint: {
                // Use step expressions (https://maplibre.org/maplibre-gl-js/docs/overview/expressions/#step)
                // with three steps to implement three types of circles:
                //   * Blue, 20px circles when point count is less than 100
                //   * Yellow, 30px circles when point count is between 100 and 750
                //   * Pink, 40px circles when point count is greater than or equal to 750
                'circle-color': [
                    'step', ['get', 'point_count'],
                    '#51bbd6', 100,
                    '#f1f075', 750,
                    '#f28cb1'
                ],
                'circle-radius': [
                    'step', ['get', 'point_count'],
                    20, 100,
                    30, 750,
                    40
                ]
            }
        });

        map.addLayer({
            id: 'cluster-count',
            type: 'symbol',
            source: 'earthquakes',
            filter: ['has', 'point_count'],
            layout: {
                'text-field': '{point_count_abbreviated}',
                'text-size': 12
            }
        });

        map.addLayer({
            id: 'unclustered-point',
            type: 'circle',
            source: 'earthquakes',
            filter: ['!', ['has', 'point_count']],
            paint: {
                'circle-color': '#11b4da',
                'circle-radius': 4,
                'circle-stroke-width': 1,
                'circle-stroke-color': '#fff'
            }
        });

        // Inspect a cluster on click
        map.on('click', 'clusters', async (e) => {
            const features = map.queryRenderedFeatures(e.point, { layers: ['clusters'] });
            const clusterId = features[0].properties.cluster_id;
            const zoom = await map.getSource('earthquakes').getClusterExpansionZoom(clusterId);
            map.easeTo({ center: features[0].geometry.coordinates, zoom });
        });

        map.on('mouseenter', 'clusters', () => { map.getCanvas().style.cursor = 'pointer'; });
        map.on('mouseleave', 'clusters', () => { map.getCanvas().style.cursor = ''; });
    });
</script>
</body>
</html>
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