path: root/README.md

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## Intro

In this repository you'll find the fully reversed source code for GTA III ([master](tree/master) branch) and GTA VC ([miami](tree/miami) branch).

It has been tested and works on Windows, Linux and FreeBSD, on x86, amd64, arm and arm64.\
Rendering is handled either by original RenderWare (D3D8)
or the reimplementation [librw](https://github.com/aap/librw) (D3D9, OpenGL 2.1 or above, OpenGL ES 2.0 or above).\
Audio is done with MSS (using dlls from original GTA) or OpenAL.

The project has also been ported to the [Nintendo Switch](https://github.com/AGraber/re3-nx/),
[Playstation Vita](https://github.com/Rinnegatamante/re3) and
[Nintendo Wii U](https://github.com/GaryOderNichts/re3-wiiu/).

We cannot build for PS2 or Xbox yet. If you're interested in doing so, get in touch with us.

## Installation

- re3 requires PC game assets to work, so you **must** own [a copy of GTA III](https://store.steampowered.com/app/12100/Grand_Theft_Auto_III/).
- Build re3 or download the latest nightly build:
  - [Windows D3D9 MSS 32bit](https://nightly.link/GTAmodding/re3/workflows/re3_msvc_x86/master/re3_Release_win-x86-librw_d3d9-mss.zip)
  - [Windows D3D9 64bit](https://nightly.link/GTAmodding/re3/workflows/re3_msvc_amd64/master/re3_Release_win-amd64-librw_d3d9-oal.zip)
  - [Windows OpenGL 64bit](https://nightly.link/GTAmodding/re3/workflows/re3_msvc_amd64/master/re3_Release_win-amd64-librw_gl3_glfw-oal.zip)
  - [Linux 64bit](https://nightly.link/GTAmodding/re3/workflows/build-cmake-conan/master/ubuntu-latest-gl3.zip)
  - [MacOS 64bit](https://nightly.link/GTAmodding/re3/workflows/build-cmake-conan/master/macos-latest-gl3.zip)
- Copy the files from the `gamefiles` directory to your game root directory. (This is not strictly necessary but very much recommended)
- Move re3 executable to GTA 3 directory and run it.

## Screenshots

![re3 2021-02-11 22-57-03-23](https://user-images.githubusercontent.com/1521437/107704085-fbdabd00-6cbc-11eb-8406-8951a80ccb16.png)
![re3 2021-02-11 22-43-44-98](https://user-images.githubusercontent.com/1521437/107703339-cbdeea00-6cbb-11eb-8f0b-07daa105d470.png)
![re3 2021-02-11 22-46-33-76](https://user-images.githubusercontent.com/1521437/107703343-cd101700-6cbb-11eb-9ccd-012cb90524b7.png)
![re3 2021-02-11 22-50-29-54](https://user-images.githubusercontent.com/1521437/107703348-d00b0780-6cbb-11eb-8afd-054249c2b95e.png)

## Improvements

We have implemented a number of changes and improvements to the original game.
They can be configured in `core/config.h`.
Some of them can be toggled at runtime, some cannot.

* Fixed a lot of smaller and bigger bugs
* User files (saves and settings) stored in GTA root directory
* Settings stored in re3.ini file instead of gta3.set
* Debug menu to do and change various things (Ctrl-M to open)
* Debug camera (Ctrl-B to toggle)
* Rotatable camera
* Xinput controller support (Windows)
* No loading screens between islands ("map memory usage" in menu)
* Skinned ped support (models from Xbox or Mobile)
* Rendering
  * Widescreen support (properly scaled HUD, Menu and FOV)
  * PS2 MatFX (vehicle reflections)
  * PS2 alpha test (better rendering of transparency)
  * PS2 particles
  * Xbox vehicle rendering
  * Xbox world lightmap rendering (needs Xbox map)
  * Xbox ped rim light
  * Xbox screen rain droplets
  * More customizable colourfilter
* Menu
  * Map
  * More options
  * Controller configuration menu
  * ...
* Can load DFFs and TXDs from other platforms, possibly with a performance penalty
* ...

## To-Do

The following things would be nice to have/do:

* Fix physics for high FPS
* Compare code with PS2 code (tedious, no good decompiler)
* [PS2 port](https://github.com/GTAmodding/re3/wiki/PS2-port)
* Xbox port (not quite as important)
* reverse remaining unused/debug functions
* compare Codewarrior build with original binary for more accurate code (very tedious)

## Modding

Asset modifications (models, texture, handling, script, ...) should work the same way as with original GTA for the most part.

Mods that make changes to the code (dll/asi, CLEO, limit adjusters) will *not* work.
Some things these mods do are already implemented in re3 (much of SkyGFX, GInput, SilentPatch, Widescreen fix),
others can easily be achieved (increasing limis, see `config.h`),
others will simply have to be rewritten and integrated into the code directly.
Sorry for the inconvenience.

## Building from Source  

When using premake, you may want to point GTA_III_RE_DIR environment variable to GTA3 root folder, if you want executable to be moved there via post-build script.

<details><summary>Linux Premake</summary>

For Linux using premake, proceed: [Building on Linux](https://github.com/GTAmodding/re3/wiki/Building-on-Linux)

</details>

<details><summary>Linux Conan</summary>

Obtain source code.
```
git clone https://github.com/GTAmodding/re3.git
cd re3
git submodule init
git submodule update --recursive
```
Install python and conan, and then run build.
```
conan export vendor/librw librw/master@
mkdir build
cd build
conan install .. re3/master@ -if build -o re3:audio=openal -o librw:platform=gl3 -o librw:gl3_gfxlib=glfw --build missing -s re3:build_type=RelWithDebInfo -s librw:build_type=RelWithDebInfo
conan build .. -if build -bf build -pf package
```
</details>

<details><summary>FreeBSD</summary>

For FreeBSD using premake, proceed: [Building on FreeBSD](https://github.com/GTAmodding/re3/wiki/Building-on-FreeBSD)

</details>

<details><summary>Windows</summary>

Assuming you have Visual Studio:
- Clone the repo using the argument `--recursive`.
- Run one of the `premake-vsXXXX.cmd` variants on root folder.
- Open the project via Visual Studio  
    
**If you use 64-bit D3D9**: We don't ship 64-bit Dx9 SDK. You need to download it from Microsoft if you don't have it(although it should come pre-installed after some Windows version)  

**If you choose OpenAL on Windows** You must read [Running OpenAL build on Windows](https://github.com/GTAmodding/re3/wiki/Running-OpenAL-build-on-Windows).
</details>

> :information_source: There are various settings in [config.h](https://github.com/GTAmodding/re3/tree/master/src/core/config.h), you may want to take a look there. i.e. FIX_BUGS define fixes the bugs we've come across.

> :information_source: **Did you notice librw?** re3 uses completely homebrew RenderWare-replacement rendering engine; [librw](https://github.com/aap/librw/). librw comes as submodule of re3, but you also can use LIBRW enviorenment variable to specify path to your own librw.

## Contributing
We have a [Coding Style](https://github.com/GTAmodding/re3/blob/master/CODING_STYLE.md) document that isn't followed or enforced very well.

Do not use features from C++11 or later.


## History

re3 was started sometime in the spring of 2018,
initially as a way to test reversed collision and physics code
inside the game.
This was done by replacing single functions of the game
with their reversed counterparts using a dll.

After a bit of work the project lay dormant for about a year
and was picked up again and pushed to github in May 2019.
At the time I (aap) had reversed around 10k lines of code and estimated
the final game to have around 200-250k.
Others quickly joined the effort and we made very quick progress
throughout the summer of 2019
after which the pace slowed down a bit.

Due to everyone staying home during the start of the Corona pandemic
everybody had a lot of time to work on re3 again and
we finally got a standalone exe in April 2020 (around 180k lines by then).

After the initial excitement and fixing and polishing the code further,
reVC was started in early May 2020 by starting from re3 code,
not by starting from scratch replacing functions with a dll.
After a few months of mostly steady progress we considered reVC
finished in December.

Since then we have started reLCS, which is currently work in progress.


## License

We don't feel like we're in a position to give this code a license.\
The code should only be used for educational, documentation and modding purposes.\
We do not encourage piracy or commercial use.\
Please keep derivate work open source and give proper credit.