Resource packs

[PureTryOut]

Vanilla Minecraft supports resource packs. They allow for players to customize textures, models, music, sounds, languages, texts such as the end poem, splashes and credits, and fonts, without any code modification.

Preferably resource packs made for vanilla Minecraft would be supported rather than using some custom format.

Do note that Minecraft nowadays supports higher resolution textures than just 16x16. I can't find an exact maximum, but this would have to be supported as well.

[iceiix]

Would also like to see this, but there are some complications. Stevenarella currently uses the 1.12.x asset format, there is an open PR for updating to 1.13.x+ assets: https://github.com/iceiix/stevenarella/pull/71 but ideally we could support both formats

[iceiix]

Investigated this a bit in #483 for #446. src/resources.rs has some support for multiple packs: an InternalPack, bundled within the app containing steven_resources, added in resources::Manager new():

        m.add_pack(Box::new(InternalPack));

The real assets are loaded in load_vanilla() with self.packs.insert() on a DirPack, and load_assets() with self.packs.insert() on an ObjectPack. So there is some support for "resource packs" internally.

For having resource packs as a user-visible feature, we would need UI (add a new page in src/screens) to select and manage resources::Manager packs, including adding new packs from disk.