Tiled UTFGrid

This example uses OpenLayers v4.0.1. The latest is v.

#### Tiled UTFGrid

This example shows how to read data from a TileUTFGrid layer.

Point to a country to see its name and flag.

Tiles made with TileMill. Hosting on MapBox.com or with open-source TileServer.
Related API documentation:

- ol.Map
,
- ol.Overlay
,
- ol.View
,
- ol.layer.Tile
,
- ol.source.TileJSON
,
- ol.source.TileUTFGrid

Copy Edit
Tiled UTFGrid This example shows how to read data from a TileUTFGrid layer. var key = 'Your Mapbox access token from http://mapbox.com/ here'; var mapLayer = new ol.layer.Tile({ source: new ol.source.TileJSON({ url: 'https://api.tiles.mapbox.com/v4/mapbox.geography-class.json?secure&access_token=' + key }) }); var gridSource = new ol.source.TileUTFGrid({ url: 'https://api.tiles.mapbox.com/v4/mapbox.geography-class.json?secure&access_token=' + key }); var gridLayer = new ol.layer.Tile({source: gridSource}); var view = new ol.View({ center: [0, 0], zoom: 1 }); var mapElement = document.getElementById('map'); var map = new ol.Map({ layers: [mapLayer, gridLayer], target: mapElement, view: view }); var infoElement = document.getElementById('country-info'); var flagElement = document.getElementById('country-flag'); var nameElement = document.getElementById('country-name'); var infoOverlay = new ol.Overlay({ element: infoElement, offset: [15, 15], stopEvent: false }); map.addOverlay(infoOverlay); var displayCountryInfo = function(coordinate) { var viewResolution = /** @type {number} */ (view.getResolution()); gridSource.forDataAtCoordinateAndResolution(coordinate, viewResolution, function(data) { // If you want to use the template from the TileJSON, // load the mustache.js library separately and call // info.innerHTML = Mustache.render(gridSource.getTemplate(), data); mapElement.style.cursor = data ? 'pointer' : ''; if (data) { flagElement.src = 'data:image/png;base64,' + data['flag_png']; nameElement.innerHTML = data['admin']; } infoOverlay.setPosition(data ? coordinate : undefined); }); }; map.on('pointermove', function(evt) { if (evt.dragging) { return; } var coordinate = map.getEventCoordinate(evt.originalEvent); displayCountryInfo(coordinate); }); map.on('click', function(evt) { displayCountryInfo(evt.coordinate); }); #country-name { color: black; font-size: 12pt; font-weight: bold; text-shadow: white 0.1em 0.1em 0.2em; } <div id="map" class="map"></div> <div style="display: none;"> <!-- Overlay with the country info --> <div id="country-info"> <div id="country-name">&nbsp;</div> <img id="country-flag" src="" /> </div> </div>

    <!DOCTYPE html>
    <html>
      <head>
        <title>Tiled UTFGrid</title>
        <link rel="stylesheet" href="https://openlayers.org/en/v4.0.1/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/v4.0.1/build/ol.js"></script>
        <style>
          #country-name {
            color: black;
            font-size: 12pt;
            font-weight: bold;
            text-shadow: white 0.1em 0.1em 0.2em;
          }
        </style>
      </head>
      <body>
        <div id="map" class="map"></div>
        <div style="display: none;">
          <!-- Overlay with the country info -->
          <div id="country-info">
            <div id="country-name">&nbsp;</div>
            <img id="country-flag" src="" />
          </div>
        </div>
        <script>
          var key = 'Your Mapbox access token from http://mapbox.com/ here';

          var mapLayer = new ol.layer.Tile({
            source: new ol.source.TileJSON({
              url: 'https://api.tiles.mapbox.com/v4/mapbox.geography-class.json?secure&access_token=' + key
            })
          });

          var gridSource = new ol.source.TileUTFGrid({
            url: 'https://api.tiles.mapbox.com/v4/mapbox.geography-class.json?secure&access_token=' + key
          });

          var gridLayer = new ol.layer.Tile({source: gridSource});

          var view = new ol.View({
            center: [0, 0],
            zoom: 1
          });

          var mapElement = document.getElementById('map');
          var map = new ol.Map({
            layers: [mapLayer, gridLayer],
            target: mapElement,
            view: view
          });

          var infoElement = document.getElementById('country-info');
          var flagElement = document.getElementById('country-flag');
          var nameElement = document.getElementById('country-name');

          var infoOverlay = new ol.Overlay({
            element: infoElement,
            offset: [15, 15],
            stopEvent: false
          });
          map.addOverlay(infoOverlay);

          var displayCountryInfo = function(coordinate) {
            var viewResolution = /** @type {number} */ (view.getResolution());
            gridSource.forDataAtCoordinateAndResolution(coordinate, viewResolution,
                function(data) {
                  // If you want to use the template from the TileJSON,
                  //  load the mustache.js library separately and call
                  //  info.innerHTML = Mustache.render(gridSource.getTemplate(), data);
                  mapElement.style.cursor = data ? 'pointer' : '';
                  if (data) {
                    flagElement.src = 'data:image/png;base64,' + data['flag_png'];
                    nameElement.innerHTML = data['admin'];
                  }
                  infoOverlay.setPosition(data ? coordinate : undefined);
                });
          };

          map.on('pointermove', function(evt) {
            if (evt.dragging) {
              return;
            }
            var coordinate = map.getEventCoordinate(evt.originalEvent);
            displayCountryInfo(coordinate);
          });

          map.on('click', function(evt) {
            displayCountryInfo(evt.coordinate);
          });
        </script>
      </body>
    </html>