View Animation

Demonstrates animated pan, zoom, and rotation.

This example shows how to use the view.animate() method to run one or more animations.

<!DOCTYPE html>
<html>
  <head>
    <title>View Animation</title>
    <link rel="stylesheet" href="https://openlayers.org/en/v4.6.4/css/ol.css" type="text/css">
    <!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"></script>
    <script src="https://openlayers.org/en/v4.6.4/build/ol.js"></script>
  </head>
  <body>
    <div id="map" class="map"></div>
    <button id="rotate-left" title="Rotate clockwise">↻</button>
    <button id="rotate-right" title="Rotate counterclockwise">↺</button>
    <button id="pan-to-london">Pan to London</button>
    <button id="elastic-to-moscow">Elastic to Moscow</button>
    <button id="bounce-to-istanbul">Bounce to Istanbul</button>
    <button id="spin-to-rome">Spin to Rome</button>
    <button id="fly-to-bern">Fly to Bern</button>
    <button id="rotate-around-rome">Rotate around Rome</button>
    <button id="tour">Take a tour</button>
    <script>
      var london = ol.proj.fromLonLat([-0.12755, 51.507222]);
      var moscow = ol.proj.fromLonLat([37.6178, 55.7517]);
      var istanbul = ol.proj.fromLonLat([28.9744, 41.0128]);
      var rome = ol.proj.fromLonLat([12.5, 41.9]);
      var bern = ol.proj.fromLonLat([7.4458, 46.95]);

      var view = new ol.View({
        center: istanbul,
        zoom: 6
      });

      var map = new ol.Map({
        target: 'map',
        layers: [
          new ol.layer.Tile({
            preload: 4,
            source: new ol.source.OSM()
          })
        ],
        // Improve user experience by loading tiles while animating. Will make
        // animations stutter on mobile or slow devices.
        loadTilesWhileAnimating: true,
        view: view
      });

      // A bounce easing method (from https://github.com/DmitryBaranovskiy/raphael).
      function bounce(t) {
        var s = 7.5625, p = 2.75, l;
        if (t < (1 / p)) {
          l = s * t * t;
        } else {
          if (t < (2 / p)) {
            t -= (1.5 / p);
            l = s * t * t + 0.75;
          } else {
            if (t < (2.5 / p)) {
              t -= (2.25 / p);
              l = s * t * t + 0.9375;
            } else {
              t -= (2.625 / p);
              l = s * t * t + 0.984375;
            }
          }
        }
        return l;
      }

      // An elastic easing method (from https://github.com/DmitryBaranovskiy/raphael).
      function elastic(t) {
        return Math.pow(2, -10 * t) * Math.sin((t - 0.075) * (2 * Math.PI) / 0.3) + 1;
      }

      function onClick(id, callback) {
        document.getElementById(id).addEventListener('click', callback);
      }

      onClick('rotate-left', function() {
        view.animate({
          rotation: view.getRotation() + Math.PI / 2
        });
      });

      onClick('rotate-right', function() {
        view.animate({
          rotation: view.getRotation() - Math.PI / 2
        });
      });

      onClick('rotate-around-rome', function() {
        // Rotation animation takes the shortest arc, so animate in two parts
        var rotation = view.getRotation();
        view.animate({
          rotation: rotation + Math.PI,
          anchor: rome,
          easing: ol.easing.easeIn
        }, {
          rotation: rotation + 2 * Math.PI,
          anchor: rome,
          easing: ol.easing.easeOut
        });
      });

      onClick('pan-to-london', function() {
        view.animate({
          center: london,
          duration: 2000
        });
      });

      onClick('elastic-to-moscow', function() {
        view.animate({
          center: moscow,
          duration: 2000,
          easing: elastic
        });
      });

      onClick('bounce-to-istanbul', function() {
        view.animate({
          center: istanbul,
          duration: 2000,
          easing: bounce
        });
      });

      onClick('spin-to-rome', function() {
        // Rotation animation takes the shortest arc, so animate in two parts
        var center = view.getCenter();
        view.animate({
          center: [
            center[0] + (rome[0] - center[0]) / 2,
            center[1] + (rome[1] - center[1]) / 2
          ],
          rotation: Math.PI,
          easing: ol.easing.easeIn
        }, {
          center: rome,
          rotation: 2 * Math.PI,
          easing: ol.easing.easeOut
        });
      });

      function flyTo(location, done) {
        var duration = 2000;
        var zoom = view.getZoom();
        var parts = 2;
        var called = false;
        function callback(complete) {
          --parts;
          if (called) {
            return;
          }
          if (parts === 0 || !complete) {
            called = true;
            done(complete);
          }
        }
        view.animate({
          center: location,
          duration: duration
        }, callback);
        view.animate({
          zoom: zoom - 1,
          duration: duration / 2
        }, {
          zoom: zoom,
          duration: duration / 2
        }, callback);
      }

      onClick('fly-to-bern', function() {
        flyTo(bern, function() {});
      });

      function tour() {
        var locations = [london, bern, rome, moscow, istanbul];
        var index = -1;
        function next(more) {
          if (more) {
            ++index;
            if (index < locations.length) {
              var delay = index === 0 ? 0 : 750;
              setTimeout(function() {
                flyTo(locations[index], next);
              }, delay);
            } else {
              alert('Tour complete');
            }
          } else {
            alert('Tour cancelled');
          }
        }
        next(true);
      }

      onClick('tour', tour);
    </script>
  </body>
</html>