AGB

Rust for the Game Boy Advance

This is a library for making games on the Game Boy Advance using the Rust programming language. The library's main focus is to provide an abstraction that allows you to develop games which take advantage of the GBA's capabilities without needing to have extensive knowledge of its low-level implementation.

agb provides the following features:

• Simple build process with minimal dependencies
• Built in importing of sprites, backgrounds, music and sound effects
• High performance audio mixer and optional tracker which can play .xm files
• Easy to use sprite and tiled background usage
• A global allocator allowing for use of both core and alloc

The documentation for the latest release can be found on docs.rs.

Getting started

The best way to get started with agb is to use the template, either within the template directory in this repository or cloning the template repository.

Once you have done this, you will find further instructions within the README in the template.

There is an (in progress) tutorial which you can find on the project website.

Help / Support

If you need any help, the discussions page is a great place to get help from the creators and contributors.

Feel free to create a new discussion in the Q&A category and we'll do our best to help!

Contributing to agb itself

In order to contribute to agb itself, you will need a few extra tools on top of what you would need to just write games for the Game Boy Advance using this library:

• Recent rustup, see the rust website for instructions for your operating system.
  • You can update rustup with rustup self update, or using your package manager if you obtained rustup in this way.
• libelf and cmake
  • Debian and derivatives: sudo apt install libelf-dev cmake
  • Arch Linux and derivatives: pacman -S libelf cmake
• mgba-test-runner
  • Run cargo install --path emulator/test-runner inside this directory
• The 'just' build tool
  • Install with cargo install just
• mdbook
  • Install with cargo install mdbook
• miri
  • Some of the unsafe code is tested using miri, install with rustup component add miri

With all of this installed, you should be able to run a full build of agb using by running

just ci

Note that before you create a PR, please file an issue so we can discuss what you are looking to change.

Structure of the repo

agb-debug - a tool you can use to decode agb stacktraces

agb-fixnum - a simple fixed point number storage since the GBA doesn't have a floating point unit, so required for performant decimals.

agb-gbafix - a clean-room reimplementation of the gbafix utility that accepts elf files rather than binaries

agb-hashmap - an no_std hashmap implementation tuned for use on the game boy advance

agb-image-converter - a crate which converts images in normal formats to a format supported by the game boy advance

agb-macros - miscellaneous proc-macros which have to be in a different crate

agb-sound-converter - a crate which converts wav files into a format supported by the game boy advance

agb - the main library code

agb/examples - basic examples often targeting 1 feature, you can run these using just run-example <example-name>

book - the source for the tutorial and website

book/games - games made as part of the tutorial

emulator - Rust bindings for the mgba emulator along with the test runner you can use to run unit tests

examples - bigger examples of a complete game, made during game jams

template - the source for the template repository

tools - misc. tools used in the development of agb itself

tracker - crates that make up the agb-tracker library which allows playing of tracker files

website - the source of the website

Stability

While agb is in the pre-1.0 phase, we follow a semi-semantic versioning scheme to ensure compatibility between minor releases. Specifically, any 0.x.y release is guaranteed to be compatible with another 0.x.z release provided that y > z, but there may be breaking changes between minor releases (i.e., changes to the second digit, e.g., between 0.1 and 0.2).

Once agb reaches version 1.0, we will transition to stronger semantic versioning, meaning that any breaking changes will be indicated by an increment to the major version (i.e., the first digit, e.g., from 1.0 to 2.0).

Acknowledgments

agb would not be possible without the help from the following (non-exhaustive) list of projects:

• The amazing work of the rust-console for making this all possible in the first place
• The asefile crate for loading aseprite files
• agbabi for providing high performance alternatives to common methods
• mgba for all the useful debugging / developer tools built in to the emulator

Licence

agb and all its subcrates are released under MPL version 2.0. See full licence text in the LICENSE file.

agb contains a subset of the code from agbabi which is released under a zlib style licence, details for which you can find under agb/src/agbabi.

The template is released under CC0 to allow you to make whatever changes you wish.

The agb logo is released under Creative Commons Attribution-ShareAlike 4.0

The music used for the examples is by Josh Woodward and released under Creative Commons Attribution 4.0

lib.rs:

Fixed point number implementation for representing non integers efficiently.