# OpenRW: an open re-implementation of the Grand Theft Auto III engine

> Re-implements Rockstar Games’ Grand Theft Auto III (2001) as a cross-platform C++ engine that runs on the data of a legitimate PC copy. It has its own loaders for the game’s RenderWare models, textures and archives, a script machine for the original mission scripts, and an optional Qt data viewer. Playability is partial: the project’s mission tracker marks six early Portland story missions as completable.

- Type: Case study
- Targets: Game
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-10-19
- Added to the catalog: 2026-10-20
- Original resource: <https://github.com/rwengine/openrw>
- Primary source: <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/README.md>
- Catalog page: <https://awesomerea.org/resources/openrw-gta3-engine-case/>
- Record JSON: <https://awesomerea.org/resources/openrw-gta3-engine-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/openrw-gta3-engine-case/index.md)

## Requirements & limits

- **Prerequisites:** README requires a legitimate copy of the original PC game, and the FAQ says the original assets cannot be distributed; the repository contains no game data. rwgame reads the game directory set in its openrw.ini configuration file, and the optional rwviewer opens objects and models from the same data.
- **Prerequisites:** Builds use CMake 3.8+ and a C++17 compiler against Boost (program_options and system, plus unit_test_framework for tests), OpenAL, Bullet, GLM, FFmpeg, SDL2 and OpenGL, with FreeType for the tools and Qt 5 for the viewer; Conan is an optional package manager. The FAQ names C++17 and OpenGL 3.3 Core as hard requirements, and README reports ports to Linux, macOS, Windows and several BSDs.
- **Scope:** The reviewed main snapshot dates from 2025-06-18; the repository has no tagged releases and the wiki says there are no official builds, so OpenRW is built from source. The playable-missions tracker (issue #52, last updated 2024-07-24) checks six story missions, all in Portland, and notes missing AI, broken cutscenes or unimplemented opcodes for many others; the FAQ says Vice City and San Andreas are not supported yet.
- **Testing evidence:** GitHub Actions jobs on Arch Linux, Fedora and Ubuntu and an AppVeyor Visual Studio 2017 job run a CTest script that builds the code and its Boost.Test unit suite; tests that need game data sit behind the TEST_DATA option, which that script does not enable. No comparison with the original executable is published.
- **License:** README applies GPL-3.0-or-later and lists FFmpeg (LGPL-2.1 or later), Bullet and SDL 2.0 (zlib) as third-party licences; the microprofile and imgui submodules are separate projects, and the game’s own assets keep their rights.

## Primary sources

1. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/README.md>
2. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/CMakeLists.txt>
3. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/cmake_options.cmake>
4. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/cmake_configure.cmake>
5. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/conanfile.py>
6. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/.gitmodules>
7. <https://github.com/rwengine/openrw/tree/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/rwcore/loaders>
8. <https://github.com/rwengine/openrw/tree/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/rwengine/src/script>
9. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/tests/CMakeLists.txt>
10. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/.github/workflows/build-and-test.yml>
11. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/.appveyor.yml>
12. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/cmake/ctest/build.ctest>
13. <https://github.com/rwengine/openrw/blob/5c5f266b71aa55aeec8cb4d823f19e7c4348f3bd/COPYING>
14. <https://github.com/rwengine/openrw/issues/52>
15. <https://github.com/rwengine/openrw/wiki/FAQ>
16. <https://github.com/rwengine/openrw/wiki/Getting-Started>
17. <https://github.com/rwengine/openrw/wiki/Configuration>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.