How Gen1Recomp Rebuilds the Gen 1 Games
Gen1Recomp is a hand-written recreation of Pokemon Red, Blue and Yellow built with Lua and the LÖVE2D framework. It replaces the original Game Boy runtime with a newly written engine while importing the maps, graphics, text and other game data it needs from a compatible ROM supplied by the user.
The project does not package a Pokemon ROM or pre-extracted game data. It also does not run the original Game Boy instructions through an emulator or translate the original assembly into a new executable.
How ROM Import Works
- Gen1Recomp checks the supplied ROM against a supported file fingerprint.
- The importer reads the game data required by the new engine.
- It creates a private generated cache for later launches.
- The ROM is released from memory and is not copied into that cache.
- The Lua/LÖVE2D engine uses the imported data during play.
The current documentation lists canonical 1 MiB US versions of Pokemon Red, Blue and Yellow. A file with a different region, revision or modification can fail validation even when its filename looks correct. The Supported Games page explains these boundaries in more detail.
Features Added by the New Engine
Gen1Recomp includes its own launcher, save handling, graphics settings, rulesets, link-play support, save editor and mod manager. These additions are possible because the project controls the new runtime rather than relying on the original Game Boy program.
This also means Gen1Recomp should not be treated as a perfectly identical copy of original hardware behavior. The project documents deliberate additions and known differences, while active development continues to change compatibility and behavior.
Why the Name “Recomp” Can Be Confusing
Static recompilation normally means translating an existing compiled program ahead of time for another target. Gen1Recomp's current architecture is documented differently: the engine is hand-written and imports data from the ROM.
The project name remains Gen1Recomp, but “native Lua/LÖVE2D recreation” is a clearer description of how it works. For a direct technical comparison, read Gen1Recomp vs Game Boy Emulation.
Gen1Recomp, ROM Hacks and VoxelMod
Gen1Recomp is not a ROM patch, and arbitrary ROM-hack support is not documented. DramaticShapeVoxelMod is a separate optional mod that changes visual presentation rather than supplying the base engine.