Merge pull request #6077 from bartvde/bing-hidpi

Optionally enable hidpi support for Bing

externs/olx.js

@@ -4135,6 +4135,7 @@ olx.source;
 /**
  * @typedef {{cacheSize: (number|undefined),
  *     culture: (string|undefined),
+ *     hidpi: (boolean|undefined),
  *     key: string,
  *     imagerySet: string,
  *     maxZoom: (number|undefined),
@@ -4153,6 +4154,14 @@ olx.source.BingMapsOptions;
 olx.source.BingMapsOptions.prototype.cacheSize;
 
 
+/**
+ * If `true` hidpi tiles will be requested. Default is `false`.
+ * @type {boolean|undefined}
+ * @api
+ */
+olx.source.BingMapsOptions.prototype.hidpi;
+
+
 /**
  * Culture code. Default is `en-us`.
  * @type {string|undefined}

src/ol/source/bingmaps.js

@@ -23,6 +23,12 @@ goog.require('ol.tilegrid');
  */
 ol.source.BingMaps = function(options) {
 
+  /**
+   * @private
+   * @type {boolean}
+   */
+  this.hidpi_ = options.hidpi !== undefined ? options.hidpi : false;
+
   ol.source.TileImage.call(this, {
     cacheSize: options.cacheSize,
     crossOrigin: 'anonymous',
@@ -31,6 +37,7 @@ ol.source.BingMaps = function(options) {
     reprojectionErrorThreshold: options.reprojectionErrorThreshold,
     state: ol.source.State.LOADING,
     tileLoadFunction: options.tileLoadFunction,
+    tilePixelRatio: this.hidpi_ ? 2 : 1,
     wrapX: options.wrapX !== undefined ? options.wrapX : true
   });
 
@@ -137,11 +144,12 @@ ol.source.BingMaps.prototype.handleImageryMetadataResponse = function(response)
     extent: extent,
     minZoom: resource.zoomMin,
     maxZoom: maxZoom,
-    tileSize: tileSize
+    tileSize: tileSize / this.getTilePixelRatio()
   });
   this.tileGrid = tileGrid;
 
   var culture = this.culture_;
+  var hidpi = this.hidpi_;
   this.tileUrlFunction = ol.TileUrlFunction.createFromTileUrlFunctions(
       resource.imageUrlSubdomains.map(function(subdomain) {
         var quadKeyTileCoord = [0, 0, 0];
@@ -164,7 +172,11 @@ ol.source.BingMaps.prototype.handleImageryMetadataResponse = function(response)
               } else {
                 ol.tilecoord.createOrUpdate(tileCoord[0], tileCoord[1],
                     -tileCoord[2] - 1, quadKeyTileCoord);
-                return imageUrl.replace('{quadkey}', ol.tilecoord.quadKey(
+                var url = imageUrl;
+                if (hidpi) {
+                  url += '&dpi=d1&device=mobile';
+                }
+                return url.replace('{quadkey}', ol.tilecoord.quadKey(
                     quadKeyTileCoord));
               }
             });