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Get features under the mouse pointer

Use queryRenderedFeatures to show properties of hovered-over map elements.

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Get features under the mouse pointer</title>
    <meta property="og:description" content="Use queryRenderedFeatures to show properties of hovered-over map elements." />
    <meta charset='utf-8'>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel='stylesheet' href='https://unpkg.com/maplibre-gl@4.2.0/dist/maplibre-gl.css' />
    <script src='https://unpkg.com/maplibre-gl@4.2.0/dist/maplibre-gl.js'></script>
    <style>
        body { margin: 0; padding: 0; }
        html, body, #map { height: 100%; }
    </style>
</head>
<body>
<style>
    #features {
        position: absolute;
        top: 0;
        right: 0;
        bottom: 0;
        width: 50%;
        overflow: auto;
        background: rgba(255, 255, 255, 0.8);
    }
    #map canvas {
        cursor: crosshair;
    }
</style>
<div id="map"></div>
<pre id="features"></pre>
<script>
    const map = new maplibregl.Map({
        container: 'map',
        style:
            'https://api.maptiler.com/maps/streets/style.json?key=get_your_own_OpIi9ZULNHzrESv6T2vL',
        center: [-96, 37.8],
        zoom: 3
    });

    map.on('mousemove', (e) => {
        const features = map.queryRenderedFeatures(e.point);

        // Limit the number of properties we're displaying for
        // legibility and performance
        const displayProperties = [
            'type',
            'properties',
            'id',
            'layer',
            'source',
            'sourceLayer',
            'state'
        ];

        const displayFeatures = features.map((feat) => {
            const displayFeat = {};
            displayProperties.forEach((prop) => {
                displayFeat[prop] = feat[prop];
            });
            return displayFeat;
        });

        document.getElementById('features').innerHTML = JSON.stringify(
            displayFeatures,
            null,
            2
        );
    });
</script>
</body>
</html>