Phaser.Cache.destroy() does not destroy cached items

[andrekampert]

This Issue is about a bug in the Phaser.Cache API 2.7.3 and below.

In method Phaser.Cache#destroy

/**
 * Clears the cache. Removes every local cache object reference.
 * If an object in the cache has a `destroy` method it will also be called.
 *
 * @method Phaser.Cache#destroy
 */
 destroy: function () {
   // ...
}

The unexpected behaviour is that most objects that are put in the cache are wrapped in another object, without a destroy method.

For example, looking at BitmapData, which has a `destroy' method:

• addBitmapData stores the actual data in a new object with keys data and frameData
• getBitmapData relies on getItem to get the correct data from the cache
• destroy does not take the property into account as getItem does and therefore does not invoke destroy on the data and frameData objects.

As a result, in this case, canvasses are never returned to the CanvasPool, causing a memory leak when loading external image data and relying on the cache to clean up old images.

Suggested solution:

• Update the destroy method to also iterate over the properties in the stored cache object. If a property contains a destroy method, invoke it on the property as well.

[samme]

Hi @andrekampert, can you test: phaser-test.js.zip

[samme]

samme@0006372

[andrekampert]

This makes a huge difference. The retained object size in our scenario is reduced to 1/10th of the amount used without the change, mainly due to the canvas pool being cleared correctly now.

Thank you very much!