Draw a linear animated line between two markers in MapBox

Question

I have seen few examples of animated line on mapbox but I haven't found any that creates a linear line between two points. I am able to create markers on the map and also to draw a line between these markers. But, I want to create that line slowly from origin(start) to destination(end). here is the code that draw line between two coordinates. I just want to make it slowly(animatedly) and then repeat that animation.

<!DOCTYPE html>
<html>
<head>
    <meta charset='utf-8' />
    <title>Animate a line</title>
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.50.0/mapbox-gl.js'></script>
    <link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.50.0/mapbox-gl.css' rel='stylesheet' />
    <style>
        body { margin:0; padding:0; }
        #map { position:absolute; top:0; bottom:0; width:100%; }
    #route {
  stroke-dasharray: 1000;
  stroke-dashoffset: 1000;
  animation: dash 1s linear alternate infinite;
}

@keyframes dash {
  from {
    stroke-dashoffset: 1000;
  }
  to {
    stroke-dashoffset: 0;
  }
}
    </style>
</head>
<body>

<div id='map'></div>
<script>
mapboxgl.accessToken =
  "pk.eyJ1IjoiaHllb25namlua2ltIiwiYSI6ImNpZXh4dXp5eDA2YjFzaGtyOGR2dnBza2oifQ.a5K673tSr0cOcYoX1rpPhg";

var map = new mapboxgl.Map({
    container: 'map',
    style: 'mapbox://styles/mapbox/streets-v9',
    center: [-122.486052, 37.830348],
    zoom: 5
});

map.on('load', function () {

    map.addLayer({
        "id": "route",
        "type": "line",

        "source": {
            "type": "geojson",
            "data": {
                "type": "Feature",
                "properties": {},
                "geometry": {
                    "type": "LineString",
                    "coordinates": [
                        [-122.414, 37.776],
                        [-77.032, 38.913]
                    ]
                }
            }
        }
    });

});
</script>

</body>
</html>

would it be a solution to devide the line into points and draw them individually, like that you can decide how fast teh whole line is drawn and where it starts to be drawn etc — Erch, Oct 23 '18 at 06:19
yes I also thought about that but I only have two coordinates, Is there any way to get coordinates after specific steps(between two coordinates). — Muhammad Haseeb, Oct 23 '18 at 06:28

score 5 · Answer 1 · edited Feb 04 '23 at 23:16

Here is a complete code for calculating the points(Lat, Long) between source and destination and then creating an animation between these two points.

<!DOCTYPE html>
<html>

  <head>
    <meta charset='utf-8' />
    <title>Animate a line</title>
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.50.0/mapbox-gl.js'></script>
    <link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.50.0/mapbox-gl.css' rel='stylesheet' />
    <style>
      body {
        margin: 0;
        padding: 0;
      }

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

    </style>
  </head>

  <body>

    <div id='map'></div>
    <script>
      mapboxgl.accessToken = 'pk.eyJ1IjoiYWhtZWRraGFuMTAzOSIsImEiOiJjam5iZDgwejYwMnlpM3FyNzJvMDZhZHdoIn0.pcOWSRI2xzY_oMX0mVsLjg';
      var map = new mapboxgl.Map({
        container: 'map',
        style: 'mapbox://styles/mapbox/dark-v9',
        center: [0.11256, 52.201733],
        zoom: 15
      });

      // Create a GeoJSON source with an empty lineString.
      var geojson = {
        "type": "FeatureCollection",
        "features": [{
          "type": "Feature",
          "geometry": {
            "type": "LineString",
            "coordinates": []
          }
        }]
      };

      var startPoint = [0.108266, 52.202758];
      var endPoint = [0.11556, 52.201733];

      var framesPerSecond = 20;
      var initialOpacity = 1
      var opacity = initialOpacity;
      var initialRadius = 4;
      var radius = initialRadius;
      var maxRadius = 15;

      var speedFactor = 100 // number of frames per longitude degree
      var animation; // to store and cancel the animation

      map.on('load', function() {

        // Point 1
        map.addSource('point1', {
          "type": "geojson",
          "data": {
            "type": "Point",
            "coordinates": [
              startPoint[0], startPoint[1]
            ]
          }
        });
        map.addLayer({
          "id": "circle1",
          "source": "point1",
          "type": "circle",
          "paint": {
            "circle-radius": initialRadius,
            "circle-radius-transition": {
              duration: 0
            },
            "circle-opacity-transition": {
              duration: 0
            },
            "circle-color": "#007cbf"
          }
        });
        map.addLayer({
          "id": "point1",
          "source": "point1",
          "type": "circle",
          "paint": {
            "circle-radius": initialRadius,
            "circle-color": "#007cbf"
          }
        });

        // Point 2
        map.addSource('point2', {
          "type": "geojson",
          "data": {
            "type": "Point",
            "coordinates": [
              endPoint[0], endPoint[1]
            ]
          }
        });
        map.addLayer({
          "id": "circle2",
          "source": "point2",
          "type": "circle",
          "paint": {
            "circle-radius": initialRadius,
            "circle-radius-transition": {
              duration: 0
            },
            "circle-opacity-transition": {
              duration: 0
            },
            "circle-color": "#007cbf"
          }
        });
        map.addLayer({
          "id": "point2",
          "source": "point2",
          "type": "circle",
          "paint": {
            "circle-radius": initialRadius,
            "circle-color": "#007cbf"
          }
        });

        //Line
        map.addLayer({
          'id': 'line-animation',
          'type': 'line',
          'source': {
            'type': 'geojson',
            'data': geojson
          },
          'layout': {
            'line-cap': 'round',
            'line-join': 'round'
          },
          'paint': {
            'line-color': '#ffffff',
            'line-width': 2
          }
        });

        var diffX = endPoint[0] - startPoint[0];
        var diffY = endPoint[1] - startPoint[1];

        var sfX = diffX / speedFactor;
        var sfY = diffY / speedFactor;

        var i = 0;
        var j = 0;

        var lineCoordinates = [];

        while (i < diffX || Math.abs(j) < Math.abs(diffY)) {
          lineCoordinates.push([startPoint[0] + i, startPoint[1] + j]);

          if (i < diffX) {
            i += sfX;
          }

          if (Math.abs(j) < Math.abs(diffY)) {
            j += sfY;
          }
        }

        console.log(lineCoordinates);

        var animationCounter = 0;

        function animateLine() {
          if (animationCounter < lineCoordinates.length) {
            geojson.features[0].geometry.coordinates.push(lineCoordinates[animationCounter]);
            map.getSource('line-animation').setData(geojson);

            requestAnimationFrame(animateLine);
            animationCounter++;
          } else {
            var coord = geojson.features[0].geometry.coordinates;
            coord.shift();
            console.log(coord);

            if (coord.length > 0) {
              geojson.features[0].geometry.coordinates = coord;
              map.getSource('line-animation').setData(geojson);

              //-------------- Point2 Animation End ---------------
              requestAnimationFrame(animateLine);
            }
          }

        }

        animateLine();


      });

    </script>

  </body>

</html>

Any idea how can I permanently change the start and end point? And also if I can have multiple lines in one shot? — Zatarra, Aug 21 '19 at 13:15
Can you explain what do you mean by permanently changing the start and end point? — Muhammad Haseeb, Aug 23 '19 at 12:04
@Muhammad, do you know how to make the line curvy rather than linear? Thanks. — kingspeech, Nov 14 '19 at 17:08
@kingspeech did you have a look at this example ? https://docs.mapbox.com/mapbox-gl-js/example/animate-point-along-route/ — Muhammad Haseeb, Nov 19 '19 at 06:36
The preferred way to draw lines within Mapbox GL JS is to express the lines as GeoJSON and add them to the map as a GeoJSONSource / line layer pair. This way you can draw lines of any shape. — Muhammad Haseeb, Nov 19 '19 at 06:37

Draw a linear animated line between two markers in MapBox

1 Answers1