Introduction

OpenGTA is a from-scratch reimplementation of Grand Theft Auto (DMA Design, 1997), the first GTA, in portable C11, based on the Windows build of the game, WINO/Grand Theft Auto.exe of Rockstar's 2002 re-release, which is the complete game: Liberty City, San Andreas and Vice City with all their missions.

It is not an emulator, a wrapper or a remake. Each subsystem of the original program is read in the disassembly and written again in C, keeping its behaviour, including its quirks and bugs. Fidelity is the point: where the port differs from the original, the port is wrong.

What you need

• Your own copy of GTA: the installed game folder, or the unzipped installer. OpenGTA contains no code, graphics, sound or text from the game, and it reads even the original's internal tables from the executable at run time. See Game data.
• gasm: OpenGTA is one WebAssembly module, opengta.wasm, for the gasm game runtime. Run it with the native runner gasm-run on macOS, Linux or Windows (Running on gasm), or in the browser on this site (Play).

How far it is

Early: the menus work and a mission starts, but you can't play it yet. Read Status before you expect a game.

Where next

• Game data: where GTA comes from and which files OpenGTA reads.
• Running on gasm and Launch parameters.
• Playing in the browser.
• Controls and Troubleshooting.
• Build from source, if you want the latest module or to help.