Merge pull request #3696 from AnalyticalGraphicsInc/imagery-reprojection

mramato · mramato · commit ac780824e1ff · 2016-03-15T14:47:48.000-04:00
Fix texture loading and re-projection bug
diff --git a/CHANGES.md b/CHANGES.md
@@ -11,6 +11,7 @@ Change Log
 * Fixed loading for KML `NetworkLink` to not append a `?` if there isn't a query string.
 * Fixed `Color.fromCssColorString` from reusing the input `result` alpha value in some cases.
 * Fix issue with billboard collections that have at least one billboard with an aligned axis and at least one billboard without an aligned axis. [#3318](https://github.com/AnalyticalGraphicsInc/cesium/issues/3318)
+* Fix a race condition that would cause the terrain to continue loading and unloading or cause a crash when changing terrain providers. [#3690](https://github.com/AnalyticalGraphicsInc/cesium/issues/3690)
 
 ### 1.19 - 2016-03-01
 
diff --git a/Source/Scene/Globe.js b/Source/Scene/Globe.js
@@ -426,7 +426,7 @@ define([
 
                     that._oceanNormalMap = that._oceanNormalMap && that._oceanNormalMap.destroy();
                     that._oceanNormalMap = new Texture({
-                        context : context,
+                        context : frameState.context,
                         source : image
                     });
                 });
diff --git a/Source/Scene/GlobeSurfaceTileProvider.js b/Source/Scene/GlobeSurfaceTileProvider.js
@@ -289,7 +289,12 @@ define([
      * @param {FrameState} frameState The frame state.
      */
     GlobeSurfaceTileProvider.prototype.initialize = function(frameState) {
-        this._imageryLayers._update();
+        var imageryLayers = this._imageryLayers;
+
+        // update collection: imagery indices, base layers, raise layer show/hide event
+        imageryLayers._update();
+        // update each layer for texture reprojection.
+        imageryLayers.queueReprojectionCommands(frameState);
 
         if (this._layerOrderChanged) {
             this._layerOrderChanged = false;
@@ -307,7 +312,6 @@ define([
             creditDisplay.addCredit(this._terrainProvider.credit);
         }
 
-        var imageryLayers = this._imageryLayers;
         for (var i = 0, len = imageryLayers.length; i < len; ++i) {
             var imageryProvider = imageryLayers.get(i).imageryProvider;
             if (imageryProvider.ready && defined(imageryProvider.credit)) {
@@ -407,6 +411,13 @@ define([
         }
     };
 
+    /**
+     * Cancels any imagery re-projections in the queue.
+     */
+    GlobeSurfaceTileProvider.prototype.cancelReprojections = function() {
+        this._imageryLayers.cancelReprojections();
+    };
+
     /**
      * Gets the maximum geometric error allowed in a tile at a given level, in meters.  This function should not be
      * called before {@link GlobeSurfaceTileProvider#ready} returns true.
diff --git a/Source/Scene/ImageryLayer.js b/Source/Scene/ImageryLayer.js
@@ -235,6 +235,8 @@ define([
         this._isBaseLayer = false;
 
         this._requestImageError = undefined;
+
+        this._reprojectComputeCommands = [];
     }
 
     defineProperties(ImageryLayer.prototype, {
@@ -739,7 +741,7 @@ define([
     }
 
     /**
-     * Reproject a texture to a {@link GeographicProjection}, if necessary, and generate
+     * Enqueues a command re-projecting a texture to a {@link GeographicProjection} on the next update, if necessary, and generate
      * mipmaps for the geographic texture.
      *
      * @private
@@ -773,12 +775,37 @@ define([
                         finalizeReprojectTexture(that, context, imagery, outputTexture);
                     }
                 });
-                frameState.commandList.push(computeCommand);
+                this._reprojectComputeCommands.push(computeCommand);
         } else {
             finalizeReprojectTexture(this, context, imagery, texture);
         }
     };
 
+    /**
+     * Updates frame state to execute any queued texture re-projections.
+     *
+     * @private
+     *
+     * @param {FrameState} frameState The frameState.
+     */
+    ImageryLayer.prototype.queueReprojectionCommands = function(frameState) {
+        var computeCommands = this._reprojectComputeCommands;
+        var length = computeCommands.length;
+        for (var i = 0; i < length; ++i) {
+            frameState.commandList.push(computeCommands[i]);
+        }
+        computeCommands.length = 0;
+    };
+
+    /**
+     * Cancels re-projection commands queued for the next frame.
+     *
+     * @private
+     */
+    ImageryLayer.prototype.cancelReprojections = function() {
+        this._reprojectComputeCommands.length = 0;
+    };
+
     ImageryLayer.prototype.getImageryFromCache = function(x, y, level, imageryRectangle) {
         var cacheKey = getImageryCacheKey(x, y, level);
         var imagery = this._imageryCache[cacheKey];
diff --git a/Source/Scene/ImageryLayerCollection.js b/Source/Scene/ImageryLayerCollection.js
@@ -459,6 +459,32 @@ define([
         });
     };
 
+    /**
+     * Updates frame state to execute any queued texture re-projections.
+     *
+     * @private
+     *
+     * @param {FrameState} frameState The frameState.
+     */
+    ImageryLayerCollection.prototype.queueReprojectionCommands = function(frameState) {
+        var layers = this._layers;
+        for (var i = 0, len = layers.length; i < len; ++i) {
+            layers[i].queueReprojectionCommands(frameState);
+        }
+    };
+
+    /**
+     * Cancels re-projection commands queued for the next frame.
+     *
+     * @private
+     */
+    ImageryLayerCollection.prototype.cancelReprojections = function() {
+        var layers = this._layers;
+        for (var i = 0, len = layers.length; i < len; ++i) {
+            layers[i].cancelReprojections();
+        }
+    };
+
     /**
      * Returns true if this object was destroyed; otherwise, false.
      * <br /><br />
diff --git a/Source/Scene/QuadtreePrimitive.js b/Source/Scene/QuadtreePrimitive.js
@@ -193,6 +193,8 @@ define([
         }
 
         this._levelZeroTiles = undefined;
+
+        this._tileProvider.cancelReprojections();
     };
 
     /**
@@ -268,6 +270,7 @@ define([
             return;
         }
 
+        // Gets commands for any texture re-projections and updates the credit display
         this._tileProvider.initialize(frameState);
 
         var debug = this._debug;
@@ -281,8 +284,6 @@ define([
         debug.tilesRendered = 0;
         debug.tilesWaitingForChildren = 0;
 
-        processTileLoadQueue(this, frameState);
-
         this._tileLoadQueue.length = 0;
         this._tileReplacementQueue.markStartOfRenderFrame();
     };
@@ -316,6 +317,8 @@ define([
             return;
         }
 
+        // Load/create resources for terrain and imagery. Prepare texture re-projections for the next frame.
+        processTileLoadQueue(this, frameState);
         updateHeights(this, frameState);
 
         var debug = this._debug;
diff --git a/Specs/Scene/ImageryLayerSpec.js b/Specs/Scene/ImageryLayerSpec.js
@@ -66,6 +66,8 @@ defineSuite([
         loadJsonp.loadAndExecuteScript = loadJsonp.defaultLoadAndExecuteScript;
         loadImage.createImage = loadImage.defaultCreateImage;
         loadWithXhr.load = loadWithXhr.defaultLoad;
+
+        frameState.commandList.length = 0;
     });
 
     function CustomDiscardPolicy() {
@@ -117,7 +119,7 @@ defineSuite([
         });
     });
 
-    it('reprojects web mercator images', function() {
+    function createWebMercatorProvider() {
         loadJsonp.loadAndExecuteScript = function(url, functionName) {
             window[functionName]({
                 "authenticationResultCode" : "ValidCredentials",
@@ -152,11 +154,14 @@ defineSuite([
             loadWithXhr.defaultLoad('Data/Images/Red16x16.png', responseType, method, data, headers, deferred);
         };
 
-        var provider = new BingMapsImageryProvider({
+        return new BingMapsImageryProvider({
             url : 'http://host.invalid',
             tileDiscardPolicy : new NeverTileDiscardPolicy()
         });
+    }
 
+    it('reprojects web mercator images', function() {
+        var provider = createWebMercatorProvider();
         var layer = new ImageryLayer(provider);
 
         return pollToPromise(function() {
@@ -176,6 +181,7 @@ defineSuite([
                 }).then(function() {
                     var textureBeforeReprojection = imagery.texture;
                     layer._reprojectTexture(frameState, imagery);
+                    layer.queueReprojectionCommands(frameState);
                     frameState.commandList[0].execute(computeEngine);
 
                     return pollToPromise(function() {
@@ -189,6 +195,34 @@ defineSuite([
         });
     });
 
+    it('cancels reprojection', function() {
+        var provider = createWebMercatorProvider();
+        var layer = new ImageryLayer(provider);
+
+        return pollToPromise(function() {
+            return provider.ready;
+        }).then(function() {
+            var imagery = new Imagery(layer, 0, 0, 0);
+            imagery.addReference();
+            layer._requestImagery(imagery);
+
+            return pollToPromise(function() {
+                return imagery.state === ImageryState.RECEIVED;
+            }).then(function() {
+                layer._createTexture(context, imagery);
+
+                return pollToPromise(function() {
+                    return imagery.state === ImageryState.TEXTURE_LOADED;
+                }).then(function() {
+                    layer._reprojectTexture(frameState, imagery);
+                    layer.cancelReprojections();
+                    layer.queueReprojectionCommands(frameState);
+                    expect(frameState.commandList.length).toEqual(0);
+                });
+            });
+        });
+    });
+
     it('basic properties work as expected', function() {
         var provider = new SingleTileImageryProvider({
             url : 'Data/Images/Red16x16.png'
