Edit

UTFGrid

utfgrid tilejson

 

This example shows how to read data from a UTFGrid source.

Point to a country to see its name and flag.

Tiles made with TileMill. Hosting on mapbox.com or with open-source TileServer.
index.html<!DOCTYPE html>
<html lang="en">
  <head>
    <title>UTFGrid</title>
    <!-- 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=fetch,requestAnimationFrame,Element.prototype.classList,URL"></script>
    <style>
      .map {
        width: 100%;
        height:400px;
      }
      #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 src="index.js"></script>
  </body>
</html>
index.jsimport 'ol/ol.css';
import Map from 'ol/Map';
import Overlay from 'ol/Overlay';
import View from 'ol/View';
import TileLayer from 'ol/layer/Tile';
import TileJSON from 'ol/source/TileJSON';
import UTFGrid from 'ol/source/UTFGrid';

var key = 'Your Mapbox access token from https://mapbox.com/ here';

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


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

var gridLayer = new TileLayer({source: gridSource});

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

var mapElement = document.getElementById('map');
var map = new 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 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);
});
package.json{
  "name": "utfgrid",
  "dependencies": {
    "ol": "6.2.1"
  },
  "devDependencies": {
    "parcel": "1.11.0"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --experimental-scope-hoisting --public-url . index.html"
  }
}