# RubySapphireRecomp — Pokémon Ruby + Sapphire, Recompiled > _This recompilation is a **byproduct of developing > [gbarecomp](https://github.com/mstan/gbarecomp)** — the games are the proving ground, the framework is the goal. > **These are in-development previews, not finished ports — expect rough > edges**, and depth will keep landing over months, not days. My time for any > one title is limited, so I ask for your patience. Contributions are welcome — > testing, issues, and PRs to the game or framework all help and will > accelerate this game's polish. More on the why at: > [Recomp + AI: 5 Months Later »](https://1379.tech/recomp-ai-5-months-later/)_ Static recompilation of **Pokémon Ruby** and **Pokémon Sapphire** (Game Boy Advance) to native PC, built on the [`gbarecomp`](https://github.com/mstan/gbarecomp) framework. One repo hosts **both** games as separate native targets sharing one source tree and one engine (the [Sonic3AndKnucklesRecomp](https://github.com/mstan/Sonic3AndKnucklesRecomp) multi-variant pattern — an `add_gba_variant()` CMake function emits one executable per game). Their Gen3 siblings live in [`FireRedLeafGreenRecomp`](https://github.com/mstan/FireRedLeafGreenRecomp) (FireRed + LeafGreen) and [`EmeraldRecomp`](https://github.com/mstan/EmeraldRecomp). > ### Status — playable bring-up (v0.0.1), and self-improving > > This is a **static-recompilation base + runner**, not a finished port. Both > games **boot through the BIOS intro to the title screen and into gameplay**. > It is **early** — not every code path is statically recompiled yet, and content > has not been exhaustively tested. (Ruby & Sapphire are the oldest Gen3 engine; > expect a few more early-boot and flash/RTC quirks than FireRed/Emerald.) > > **It gets better the more you play.** Any code path the static recompiler hasn't > covered runs through a built-in **interpreter the first time it's hit**, then is > **JIT-compiled to native** (in-process, no toolchain needed) and **remembered on > disk** — so the next launch runs it natively from the start. Interpreted once, > native ever after; coverage grows toward fully-native as the game is played. See > [How it self-improves](#how-it-self-improves). --- ## Screenshots | Pokémon Ruby | Pokémon Sapphire | |---|---| | ![Pokémon Ruby — title screen, native recompiled build](docs/screenshots/ruby.png) | ![Pokémon Sapphire — title screen, native recompiled build](docs/screenshots/sapphire.png) | *Native recompiled builds (no emulator), captured running the original ROMs.* --- ## What "static recompilation" means here The ROM's **ARM7TDMI machine code is statically translated to native C** — every function the game runs becomes a real generated C function. Unlike most recomp projects, **the GBA BIOS is recompiled and executed too** (not HLE'd or stubbed), so the boot sequence and interrupt/SWI handlers run as real recompiled code. The rest of the console — the PPU (graphics), APU + M4A sound engine, DMA, timers, the cartridge flash save chip + RTC, and hardware I/O — is modeled by the `gbarecomp` runtime. Only **symbol metadata** (function names, addresses, sizes) from the [`pret/pokeruby`](https://github.com/pret/pokeruby) decompilation enters this repo — never its C source, build output, or toolchain. **The ROM is never redistributed**; you supply your own legally-dumped copy. ## Variants | Target | Game | ROM (USA) | SHA-1 | Debug port | |------------------|-------------------|-------------|-------------------------------------------|------------| | `RubyRecomp` | Pokémon Ruby | rev1 | `610b96a9c9a7d03d2bafb655e7560ccff1a6d894` | 19872 | | `SapphireRecomp` | Pokémon Sapphire | rev1 | `4722efb8cd45772ca32555b98fd3b9719f8e60a9` | 19882 | The runtime **refuses to launch on an unrecognized ROM** — the SHA-1 must match. ## Quick start 1. Download the latest `RubyRecomp-` / `SapphireRecomp-windows-x64` zip from [Releases](../../releases) and extract it (or build from source — see below). 2. Run the executable for the game you built. 3. Supply your own **legally-obtained** Ruby / Sapphire (USA) ROM when prompted. The path is cached next to the exe for future launches. 4. Play. Early on you may briefly see the interpreter warm up new code paths; once warmed (and cached), they run native. ## Controls | GBA button | Keyboard | |------------|---------------| | D-Pad | Arrow keys | | A | Z | | B | X | | Start | Enter | | Select | Backspace | Save states: **Shift+F1–F9** save to a slot, **F1–F9** load it. ## How it self-improves `gbarecomp`'s coverage is honest: a path that wasn't statically recompiled is **bridged through the interpreter** the first time, *loudly*, then healed: - **First hit:** the interpreter runs the missed function (correct, just not native) and the runtime records it. - **Heal:** the function is **JIT-compiled to native in-process** via a toolchain-less backend (sljit) — no compiler required on your machine. - **Persist:** the healed path is written to a per-ROM cache (`recomp_cache//`), so **the next launch re-JITs it up front** and it runs native from the start. The result is a game that converges toward fully-native execution the more it's played, and **stays** improved across launches. A handful of instruction patterns the JIT can't lower yet stay on the interpreter (precision over recall); those are emitter gaps that close over time. Self-improvement is on by default; set `GBARECOMP_SELFHEAL_RECOMPILE=0` for a pure-interpreter run. ## Building from source **Prerequisites (Windows):** [MSYS2](https://www.msys2.org/) with the mingw64 toolchain (`gcc`/`g++`), CMake 3.16+, Ninja, and SDL2 (mingw64 package). Builds are invoked from PowerShell with the mingw64 toolchain on `PATH`. **1. Clone this repo next to `gbarecomp`** (the game repo builds against the sibling engine checkout on `main`): ``` git clone https://github.com/mstan/gbarecomp.git git clone https://github.com/mstan/RubySapphireRecomp.git cd RubySapphireRecomp ``` **2. Supply your ROM(s)** at `variants/ruby/roms/ruby_usa.gba` and/or `variants/sapphire/roms/sapphire_usa.gba` (SHA-1s above). ROMs are gitignored and never committed. **3. Recompile + build.** The committed `variants/*/symbols/*.toml` are the importer output, so you can regenerate the C and build directly: ``` # from PowerShell, mingw64 on PATH gba_recompile --rom variants/ruby/roms/ruby_usa.gba \ --config variants/ruby/symbols/ruby_usa.toml \ --out variants/ruby/generated cmake -S . -B build -G Ninja cmake --build build --target RubyRecomp ``` (`gba_recompile` is built from the `gbarecomp` checkout; see that repo's README.) The recompiled translation unit is large — expect a multi-minute compile. ## License PolyForm Noncommercial 1.0.0 — see [`LICENSE`](LICENSE). Third-party components retain their own licenses. ## Legal This project contains **no copyrighted ROM data, no Nintendo BIOS, and no decomp source** — only original recompiler/runtime code and symbol metadata. **You must supply your own legally-dumped ROM** (and BIOS, where the runtime requires one). Pokémon, Ruby, and Sapphire are trademarks of Nintendo / Game Freak / The Pokémon Company; this project is an unaffiliated, non-commercial preservation and research effort. ---

R.A.I.D. — Retro AI Development · a Discord for AI-assisted retro reverse-engineering, decomp & recomp

Join the Retro AI Development (R.A.I.D.) Discord