demo.js

/**
 * Display clustered markers on a map
 *
 * Note that the maps clustering module https://js.api.here.com/v3/3.1/mapsjs-clustering.js
 * must be loaded to use the Clustering

 * @param {H.Map} map A HERE Map instance within the application
 * @param {Object[]} data Raw data that contains airports' coordinates
*/
function startClustering(map, data) {
  // First we need to create an array of DataPoint objects,
  // for the ClusterProvider
  var dataPoints = data.map(function (item) {
    return new H.clustering.DataPoint(item.latitude, item.longitude);
  });

  // Create a clustering provider with custom options for clusterizing the input
  var clusteredDataProvider = new H.clustering.Provider(dataPoints, {
    clusteringOptions: {
      // Maximum radius of the neighbourhood
      eps: 32,
      // minimum weight of points required to form a cluster
      minWeight: 2
    }
  });

  // Create a layer that will consume objects from our clustering provider
  var clusteringLayer = new H.map.layer.ObjectLayer(clusteredDataProvider);

  // To make objects from clustering provder visible,
  // we need to add our layer to the map
  map.addLayer(clusteringLayer);
}

/**
 * Boilerplate map initialization code starts below:
 */

// Step 1: initialize communication with the platform
// In your own code, replace variable window.apikey with your own apikey
var platform = new H.service.Platform({
  apikey: window.apikey
});

var defaultLayers = platform.createDefaultLayers();

// Step 2: initialize a map
var map = new H.Map(document.getElementById('map'), defaultLayers.vector.normal.map, {
  center: new H.geo.Point(30.789, 33.790),
  zoom: 2,
  pixelRatio: window.devicePixelRatio || 1
});
// add a resize listener to make sure that the map occupies the whole container
window.addEventListener('resize', () => map.getViewPort().resize());

// Step 3: make the map interactive
// MapEvents enables the event system
// Behavior implements default interactions for pan/zoom (also on mobile touch environments)
var behavior = new H.mapevents.Behavior(new H.mapevents.MapEvents(map));


// Step 4: create the default UI component, for displaying bubbles
var ui = H.ui.UI.createDefault(map, defaultLayers);

// Step 5: cluster data about airports's coordinates
// airports variable was injected at the page load
startClustering(map, airports);