Greedify the queue loading strategy

src/ol/tilequeue.js

@@ -89,16 +89,17 @@ ol.TileQueue.prototype.handleTileChange = function(event) {
  * @param {number} maxNewLoads Maximum number of new tiles to load.
  */
 ol.TileQueue.prototype.loadMoreTiles = function(maxTotalLoading, maxNewLoads) {
-  var newLoads = Math.min(
-      maxTotalLoading - this.getTilesLoading(), maxNewLoads, this.getCount());
-  var i, tile;
-  for (i = 0; i < newLoads; ++i) {
+  var newLoads = 0;
+  var tile;
+  while (this.tilesLoading_ < maxTotalLoading && newLoads < maxNewLoads &&
+         this.getCount() > 0) {
     tile = /** @type {ol.Tile} */ (this.dequeue()[0]);
     if (tile.getState() === ol.TileState.IDLE) {
       goog.events.listen(tile, goog.events.EventType.CHANGE,
           this.handleTileChange, false, this);
       tile.load();
       ++this.tilesLoading_;
+      ++newLoads;
     }
   }
 };