Measure distances

Click points on a map to create lines that measure distanced using turf.length. See the example: https://docs.mapbox.com//mapbox-gl-js/example/measure/

by jscastro76

HTML

<script src="https://api.mapbox.com/mapbox-gl-js/v2.1.1/mapbox-gl.js"></script>
<script src="https://npmcdn.com/@turf/[email protected]/turf.min.js"></script>
<link rel="stylesheet" href="https://api.mapbox.com/mapbox-gl-js/v2.1.1/mapbox-gl.css">



<div id="map"></div>
<div id="distance" class="distance-container"></div>

CSS

body { margin: 0; padding: 0; }
	#map { position: absolute; top: 0; bottom: 0; width: 100%; }

    .distance-container {
        position: absolute;
        top: 10px;
        left: 10px;
        z-index: 1;
    }

    .distance-container > * {
        background-color: rgba(0, 0, 0, 0.5);
        color: #fff;
        font-size: 11px;
        line-height: 18px;
        display: block;
        margin: 0;
        padding: 5px 10px;
        border-radius: 3px;
    }

JavaScript

var shop = [73.91061898, 18.565461492];
	mapboxgl.accessToken = 'PASTE HERE YOUR TOKEN';
    var map = new mapboxgl.Map({
        container: 'map',
        style: 'mapbox://styles/mapbox/streets-v11',
        center: shop,
        zoom: 12
    });

    var distanceContainer = document.getElementById('distance');

    // GeoJSON object to hold our measurement features
    var geojson = {
        'type': 'FeatureCollection',
        'features': []
    };

    // Used to draw a line between points
    var linestring = {
        'type': 'Feature',
        'geometry': {
            'type': 'LineString',
            'coordinates': []
        }
    };

    map.on('load', function () {
        map.addSource('geojson', {
            'type': 'geojson',
            'data': geojson
        });

        // Add styles to the map
        map.addLayer({
            id: 'measure-points',
            type: 'circle',
            source: 'geojson',
            paint: {
                'circle-radius': 5,
                'circle-color': '#000'
            },
            filter: ['in', '$type', 'Point']
        });
        map.addLayer({
            id: 'measure-lines',
            type: 'line',
            source: 'geojson',
            layout: {
                'line-cap': 'round',
                'line-join': 'round'
            },
            paint: {
                'line-color': '#000',
                'line-width': 2.5
            },
            filter: ['in', '$type', 'LineString']
        });

        map.on('click', function (e) {
            var features = map.queryRenderedFeatures(e.point, {
                layers: ['measure-points']
            });

            // Remove the linestring from the group
            // So we can redraw it based on the points collection
            if (geojson.features.length > 1) geojson.features.pop();

            // Clear the Distance container to populate it with a new value
            distanceContainer.innerHTML = '';

            // If...