Cache#Cache

Phaser has one single cache in which it stores all assets.

The cache is split up into sections, such as images, sounds, video, json, etc. All assets are stored using
a unique string-based key as their identifier. Assets stored in different areas of the cache can have the
same key, for example 'playerWalking' could be used as the key for both a sprite sheet and an audio file,
because they are unique data types.

The cache is automatically populated by the Phaser.Loader. When you use the loader to pull in external assets
such as images they are automatically placed into their respective cache. Most common Game Objects, such as
Sprites and Videos automatically query the cache to extract the assets they need on instantiation.

You can access the cache from within a State via this.cache. From here you can call any public method it has,
including adding new entries to it, deleting them or querying them.

Understand that almost without exception when you get an item from the cache it will return a reference to the
item stored in the cache, not a copy of it. Therefore if you retrieve an item and then modify it, the original
object in the cache will also be updated, even if you don't put it back into the cache again.

By default when you change State the cache is not cleared, although there is an option to clear it should
your game require it. In a typical game set-up the cache is populated once after the main game has loaded and
then used as an asset store.