Merge pull request #286 from elemoine/droppedtile

Fix tile change event handling

src/ol/renderer/canvas/canvastilelayerrenderer.js

@@ -158,8 +158,7 @@ ol.renderer.canvas.TileLayer.prototype.renderFrame =
 
       tileState = tile.getState();
       if (tileState == ol.TileState.IDLE) {
-        goog.events.listenOnce(tile, goog.events.EventType.CHANGE,
-            this.handleTileChange, false, this);
+        this.listenToTileChange(tile);
         this.updateWantedTiles(frameState.wantedTiles, tileSource, tileCoord);
         tileCenter = tileGrid.getTileCoordCenter(tileCoord);
         frameState.tileQueue.enqueue(tile, tileSourceKey, tileCenter);

src/ol/renderer/dom/domtilelayerrenderer.js

@@ -116,8 +116,7 @@ ol.renderer.dom.TileLayer.prototype.renderFrame =
 
       tileState = tile.getState();
       if (tileState == ol.TileState.IDLE) {
-        goog.events.listenOnce(tile, goog.events.EventType.CHANGE,
-            this.handleTileChange, false, this);
+        this.listenToTileChange(tile);
         this.updateWantedTiles(frameState.wantedTiles, tileSource, tileCoord);
         tileCenter = tileGrid.getTileCoordCenter(tileCoord);
         frameState.tileQueue.enqueue(tile, tileSourceKey, tileCenter);

src/ol/renderer/layerrenderer.js

@@ -40,6 +40,12 @@ ol.renderer.Layer = function(mapRenderer, layer) {
    */
   this.layer_ = layer;
 
+  /**
+   * @protected
+   * @type {Object.<string, boolean>}
+   */
+  this.observedTileKeys = {};
+
   goog.events.listen(this.layer_,
       ol.Object.getChangedEventType(ol.layer.LayerProperty.BRIGHTNESS),
       this.handleLayerBrightnessChange, false, this);
@@ -167,13 +173,29 @@ ol.renderer.Layer.prototype.handleLayerVisibleChange = function() {
 /**
  * Handle changes in tile state.
  * @param {goog.events.Event} event Tile change event.
- * @protected
+ * @private
  */
-ol.renderer.Layer.prototype.handleTileChange = function(event) {
+ol.renderer.Layer.prototype.handleTileChange_ = function(event) {
   var tile = /** @type {ol.Tile} */ (event.target);
   if (tile.getState() === ol.TileState.LOADED) {
     this.getMap().requestRenderFrame();
   }
+  delete this.observedTileKeys[tile.getKey()];
+};
+
+
+/**
+ * Listen once to titileKey, le change event.
+ * @param {ol.Tile} tile Tile.
+ * @protected
+ */
+ol.renderer.Layer.prototype.listenToTileChange = function(tile) {
+  var tileKey = tile.getKey();
+  if (!(tileKey in this.observedTileKeys)) {
+    this.observedTileKeys[tileKey] = true;
+    goog.events.listenOnce(tile, goog.events.EventType.CHANGE,
+        this.handleTileChange_, false, this);
+  }
 };
 
 

src/ol/renderer/webgl/webgltilelayerrenderer.js

@@ -391,8 +391,7 @@ ol.renderer.webgl.TileLayer.prototype.renderFrame =
 
         tileState = tile.getState();
         if (tileState == ol.TileState.IDLE) {
-          goog.events.listenOnce(tile, goog.events.EventType.CHANGE,
-              this.handleTileChange, false, this);
+          this.listenToTileChange(tile);
           this.updateWantedTiles(frameState.wantedTiles, tileSource, tileCoord);
           tileCenter = tileGrid.getTileCoordCenter(tileCoord);
           frameState.tileQueue.enqueue(tile, tileSourceKey, tileCenter);

src/ol/tile.js

@@ -1,3 +1,5 @@
+// FIXME should inQueue be private?
+
 goog.provide('ol.Tile');
 goog.provide('ol.TileState');
 
@@ -28,6 +30,13 @@ ol.Tile = function(tileCoord) {
 
   goog.base(this);
 
+  /**
+   * A count incremented each time the tile is inQueue in a tile queue,
+   * and decremented each time the tile is dequeued from a tile queue.
+   * @type {number}
+   */
+  this.inQueue = 0;
+
   /**
    * @type {ol.TileCoord}
    */

src/ol/tilequeue.js

@@ -89,6 +89,8 @@ ol.TileQueue.prototype.dequeue_ = function() {
   }
   var tileKey = tile.getKey();
   delete this.queuedTileKeys_[tileKey];
+  tile.inQueue--;
+  goog.asserts.assert(tile.inQueue >= 0);
   return tile;
 };
 
@@ -110,6 +112,8 @@ ol.TileQueue.prototype.enqueue = function(tile, tileSourceKey, tileCenter) {
       this.heap_.push([priority, tile, tileSourceKey, tileCenter]);
       this.queuedTileKeys_[tileKey] = true;
       this.siftDown_(0, this.heap_.length - 1);
+      tile.inQueue++;
+      goog.asserts.assert(tile.inQueue > 0);
     }
   }
 };
@@ -246,6 +250,11 @@ ol.TileQueue.prototype.reprioritize = function() {
     if (priority == ol.TileQueue.DROP) {
       tileKey = tile.getKey();
       delete this.queuedTileKeys_[tileKey];
+      tile.inQueue--;
+      goog.asserts.assert(tile.inQueue >= 0);
+      if (tile.inQueue === 0) {
+        goog.events.removeAll(tile);
+      }
     } else {
       node[0] = priority;
       heap[n++] = node;

test/spec/ol/tilequeue.test.js

@@ -21,13 +21,20 @@ describe('ol.TileQueue', function() {
   }
 
   function addRandomPriorityTiles(tq, num) {
+    var tiles = [];
     var i, tile, priority;
     for (i = 0; i < num; i++) {
       tile = new ol.Tile();
+      tile.toDrop = (i % 2 === 0) ? true : false;
+      goog.events.listen(tile, goog.events.EventType.CHANGE,
+          goog.nullFunction);
       priority = Math.floor(Math.random() * 100);
       tq.heap_.push([priority, tile, '', new ol.Coordinate(0, 0)]);
       tq.queuedTileKeys_[tile.getKey()] = true;
+      tile.inQueue++;
+      tiles.push(tile);
     }
+    return tiles;
   }
 
   describe('heapify', function() {
@@ -45,16 +52,15 @@ describe('ol.TileQueue', function() {
     it('does reprioritize the array', function() {
 
       var tq = new ol.TileQueue(function() {});
-      addRandomPriorityTiles(tq, 100);
+      var tiles = addRandomPriorityTiles(tq, 100);
 
       tq.heapify_();
 
       // now reprioritize, changing the priority of 50 tiles and removing the
       // rest
 
-      var i = 0;
-      tq.tilePriorityFunction_ = function() {
-        if ((i++) % 2 === 0) {
+      tq.tilePriorityFunction_ = function(tile) {
+        if (tile.toDrop) {
           return ol.TileQueue.DROP;
         }
         return Math.floor(Math.random() * 100);
@@ -64,10 +70,23 @@ describe('ol.TileQueue', function() {
       expect(tq.heap_.length).toEqual(50);
       expect(isHeap(tq)).toBeTruthy();
 
+      var i, tile;
+      for (i = 0; i < tiles.length; ++i) {
+        tile = tiles[i];
+        var hasListener = goog.events.hasListener(tile);
+        if (tile.toDrop) {
+          expect(hasListener).toBeFalsy();
+        } else {
+          expect(hasListener).toBeTruthy();
+        }
+      }
+
     });
   });
 });
 
+goog.require('goog.events');
+goog.require('goog.events.EventType');
 goog.require('ol.Coordinate');
 goog.require('ol.Tile');
 goog.require('ol.TileQueue');