feat!: Use Flame.images in flame_texturepacker

[ABausG]

Description

Using Flame.images instead of a custom ImageCache in TexturePackerAtlas allowing users to override the ImageCache's prefix to support loading Atlas Animations from different packages.
Due to this change the prefix of the used ImageCache changed from assets/ to assets/images/

Checklist

• I have followed the Contributor Guide when preparing my PR.
• I have updated/added tests for ALL new/updated/fixed functionality.
• I have updated/added relevant documentation in docs and added dartdoc comments with ///.
• I have updated/added relevant examples in examples or docs.

Breaking Change?

• Yes, this PR is a breaking change.
• No, this PR is not a breaking change.

Migration instructions

Either move all sprites and textures from assets/ to assets/images/ or provide a custom cache using images: Images(prefix: 'assets/')or use Flame.images.prefix = 'assets/' to point to the same Location as before. Be aware that the latter approach might interfere with loading other Image Assets

Related Issues

Closes #3096

[spydon]

I was going to suggest that we let the user pass in an optional custom cache too, but since that argument will have to go through so many methods I think we can leave that as a follow-up for when someone needs it.

[ABausG]

[...] that argument will have to go through so many methods

If I counted correctly it would be ~6 methods with a maximum call chain of 3. This would then still be kind of reasonable I guess.

If this route is taken would you suggest we keep a Images(prefix: 'assets/') as the default? Then this wouldn't even be a breaking change!

Happy to adjust that @spydon

[spydon]

If I counted correctly it would be ~6 methods with a maximum call chain of 3. This would then still be kind of reasonable I guess.

Alright, if you want to adjust it you can follow how it's done in the parallax:
https://github.com/flame-engine/flame/blob/main/packages/flame/lib/src/parallax.dart#L147

If this route is taken would you suggest we keep a Images(prefix: 'assets/') as the default? Then this wouldn't even be a breaking change!

I think the breaking change is still worth it, it's good to default to Flame.images like everywhere else.

[ABausG]

@spydon adjusted to pass the custom cache through. Also applying the custom cache for the Assets Loading.

Also adjusted the PR description to include the 3rd way of migrating the version

[spydon]

Lgtm