Create a Heatmap Layer

Visualize point density using a heatmap layer.

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: [-119.5, 36.0],
        zoom: 6,
        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'
        });

        map.addLayer({
            id: 'earthquakes-heatmap',
            type: 'heatmap',
            source: 'earthquakes',
            maxzoom: 9,
            paint: {
                'heatmap-weight': ['interpolate', ['linear'], ['get', 'mag'], 0, 0, 6, 1],
                'heatmap-intensity': ['interpolate', ['linear'], ['zoom'], 0, 1, 9, 3],
                'heatmap-color': [
                    'interpolate', ['linear'], ['heatmap-density'],
                    0,   'rgba(33,102,172,0)',
                    0.2, 'rgb(103,169,207)',
                    0.4, 'rgb(209,229,240)',
                    0.6, 'rgb(253,219,199)',
                    0.8, 'rgb(239,138,98)',
                    1,   'rgb(178,24,43)'
                ],
                'heatmap-radius': ['interpolate', ['linear'], ['zoom'], 0, 2, 9, 20],
                'heatmap-opacity': ['interpolate', ['linear'], ['zoom'], 7, 1, 9, 0]
            }
        });

        map.addLayer({
            id: 'earthquakes-point',
            type: 'circle',
            source: 'earthquakes',
            minzoom: 7,
            paint: {
                'circle-radius': ['interpolate', ['linear'], ['zoom'],
                    7, ['interpolate', ['linear'], ['get', 'mag'], 1, 1, 6, 4],
                    16, ['interpolate', ['linear'], ['get', 'mag'], 1, 5, 6, 50]
                ],
                'circle-color': ['interpolate', ['linear'], ['get', 'mag'],
                    1, 'rgba(33,102,172,0)',
                    2, 'rgb(103,169,207)',
                    3, 'rgb(209,229,240)',
                    4, 'rgb(253,219,199)',
                    5, 'rgb(239,138,98)',
                    6, 'rgb(178,24,43)'
                ],
                'circle-stroke-color': 'white',
                'circle-stroke-width': 1,
                'circle-opacity': ['interpolate', ['linear'], ['zoom'], 7, 0, 8, 1]
            }
        });
    });

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Create a Heatmap Layer – Maptoolkit Maps JS</title>
    <meta property="og:description" content="Visualize point density using a heatmap layer." />
    <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: [-119.5, 36.0],
        zoom: 6,
        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'
        });

        map.addLayer({
            id: 'earthquakes-heatmap',
            type: 'heatmap',
            source: 'earthquakes',
            maxzoom: 9,
            paint: {
                'heatmap-weight': ['interpolate', ['linear'], ['get', 'mag'], 0, 0, 6, 1],
                'heatmap-intensity': ['interpolate', ['linear'], ['zoom'], 0, 1, 9, 3],
                'heatmap-color': [
                    'interpolate', ['linear'], ['heatmap-density'],
                    0,   'rgba(33,102,172,0)',
                    0.2, 'rgb(103,169,207)',
                    0.4, 'rgb(209,229,240)',
                    0.6, 'rgb(253,219,199)',
                    0.8, 'rgb(239,138,98)',
                    1,   'rgb(178,24,43)'
                ],
                'heatmap-radius': ['interpolate', ['linear'], ['zoom'], 0, 2, 9, 20],
                'heatmap-opacity': ['interpolate', ['linear'], ['zoom'], 7, 1, 9, 0]
            }
        });

        map.addLayer({
            id: 'earthquakes-point',
            type: 'circle',
            source: 'earthquakes',
            minzoom: 7,
            paint: {
                'circle-radius': ['interpolate', ['linear'], ['zoom'],
                    7, ['interpolate', ['linear'], ['get', 'mag'], 1, 1, 6, 4],
                    16, ['interpolate', ['linear'], ['get', 'mag'], 1, 5, 6, 50]
                ],
                'circle-color': ['interpolate', ['linear'], ['get', 'mag'],
                    1, 'rgba(33,102,172,0)',
                    2, 'rgb(103,169,207)',
                    3, 'rgb(209,229,240)',
                    4, 'rgb(253,219,199)',
                    5, 'rgb(239,138,98)',
                    6, 'rgb(178,24,43)'
                ],
                'circle-stroke-color': 'white',
                'circle-stroke-width': 1,
                'circle-opacity': ['interpolate', ['linear'], ['zoom'], 7, 0, 8, 1]
            }
        });
    });
</script>
</body>
</html>

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