fm4-static-recomp

FM4 Static Recomp

An unofficial static recompilation of the Xbox 360 release of Forza Motorsport 4 for Windows, built on your own PC from your own disc.

The game's PowerPC code is translated ahead of time into C++ by the ShiftGlue SDK and compiled for x86-64. Its GPU commands run on ShiftGlue's native Vulkan renderer, written for Pinyon Shift (Forza Horizon) and extended here for FM4.

New in 0.3.0: DLSS, FSR 2 and FSR 3

3840x2160 (3x), 120 fps	2560x1440 (2x), 160 fps
Nürburgring GP, BMW M3 E92	Hockenheimring Short, BMW M5

_{YouTube plays video at up to 60 fps; the frame rates are the game's during the recording.}

Quick start

1. Download FM4StaticRecomp-Launcher.zip from the latest release and extract it into a short folder you own, for example D:\FM4.
2. Start FM4StaticRecompLauncher.exe and follow its five setup steps: Disc 1, Disc 2 (optional), the Microsoft licence, the build and your profile.
3. Press PLAY.

The first setup takes about 40 minutes. Details: Launcher guide. Prefer the command line? See the manual install.

Documentation

Guide	What's in it
Launcher	First setup, profiles, content, the data folder, updates
Manual install	Command-line setup, Disc 2 and DLC, updating
Graphics settings	The in-game GRAPHICS page, presets, what each setting does
Upscalers	DLSS, FSR 2 and FSR 3: what to pick, how the port feeds them, known limits
High frame rates	Picking a frame rate, how the game runs at up to 240 fps at real speed, limits
Keyboard	Key layout for driving and menus, rebinding
Launch options	Command-line options, languages, -Compat, frame generation, setting options, logs and crash reports
Debug options	Debug views, A/B switches of rendering fixes and diagnostics
Testing and benchmarks	What was played, frame rates and VRAM, comparison with Xenia
Reporting issues	Checklist and template for a bug report

Features

Compared with the original console, and with the same translation built against the stock ShiftGlue SDK (without this project's game hooks and renderer changes):

	Xbox 360	Stock ShiftGlue SDK	FM4 Static Recomp
Resolution	1280x720	1x to 4x of 720p, but the road and car shadows render wrong	1x to 4x of 720p (up to 5120x2880), switchable live
Race frame rate	60 fps	The console's pacing	60 fps up to the display's refresh rate (at most 240) (how)
Menus and showroom	60 / 30 fps	The console's pacing	The race frame rate; animations and the showroom camera run at real time
Race loading	Console speed	Console speed	Faster
Sun and lights	Correct	Screen-filling glare	Correct
Anti-aliasing	The game's 2x/4x MSAA	The game's MSAA	Showroom and race MSAA 4x, 2x or off each, FXAA, FXAA Extreme, DLAA
Upscaling	-	DLSS, FSR 2 and FSR 3 with Forza Horizon's camera tracking, which does not fit FM4	DLSS, FSR 2 and FSR 3 with FM4's own depth, camera cuts and per-object motion (how)
Graphics settings	Fixed	Launch options only	In-game GRAPHICS page (BACK + START or F6) with presets and per-setting switches, saved between sessions
VRAM at 3x	-	About 8 GB	About 2.5 GB
Input	Controller	XInput gamepad	XInput gamepad and keyboard, with keycap button prompts
Disc 2 and DLC	From the disc and Marketplace	Not wired up	Installed at launch from folders you name
Frame generation tools	-	Not visible to them	Opt-in for Lossless Scaling and NVIDIA Smooth Motion
Xbox LIVE, Kinect	Yes (LIVE servers closed)	No	No

About twice Xenia's frame rate at every scale on the same PC (benchmarks).

Supported game

Game	Forza Motorsport 4, Xbox 360, retail, title ID 4D530910
Disc 1, 1.0 PAL	Europe, Australia, media ID 61D62D9F
Disc 1, 1.0 USA	USA, media ID 26FF1101
Disc 2	Optional: the install disc's four content packages (more cars and tracks)
DLC	Optional: Marketplace packages for title 4D530910

Both Disc 1 releases carry the same code; only their executables' headers differ. Any other version of default.xex will not work, because the translation is made for this exact code. Other releases are untested. config/supported-discs.json lists every Disc 1 file with its size and hash.

What you need

• Windows 10 version 2004 (build 19041) or newer, 64-bit.
• A GPU with a current Vulkan driver.
• An XInput gamepad (an Xbox controller, or another pad through a mapper), or the keyboard.
• Your own Forza Motorsport 4 Disc 1, as an ISO or a Games on Demand (GOD) copy. Disc 2 and DLC are optional.
• An internet connection for the first setup. No administrator permission and no Visual Studio: setup downloads the parts of Microsoft's C++ runtime and Windows SDK the build needs (about 300 MB) once you accept their licences.
• About 17 GB of disk space (Disc 1 7.6 GB, the repository with the SDK and build 3.3 GB, the build tools with Microsoft's files and their downloads 6.3 GB), plus about 5 GB for Disc 2 and DLC.
• About 40 minutes for the first setup; a rebuild after an update takes minutes.

Known issues

Known problems are tracked as open issues. Found a new one? See Reporting issues.

Roadmap

1. Upscaler polish: the mirrors and the remaining shimmer (see Known limitations).
2. Project Forza Plus support.
3. Racing wheels, starting with MOZA wheels.
4. Linux: a native build of the game and the launcher.
5. Other disc releases, such as the Essentials Edition.
6. More tests on niche or legacy hardware.

Repository layout

Where things are

Path	What it is
src/	The host app: game hooks, built-in defaults, Disc 2 and DLC install, the GRAPHICS page
src/input/	Keyboard play: bindings, driving smoothing, keycap prompts
tests/	Unit tests of the host app
config/rexglue/	The recompiler's input: function analysis, hooks, the manifest
config/*.json	The pinned toolchain and SDK, the supported discs' file lists
tools/setup.ps1, build.ps1, codegen.ps1, run.ps1	Setup, build and launch
launcher/	The launcher (Avalonia, .NET 8): its core library with tests, and the app
tools/package-release.ps1	Builds the release assets and the players' zip
config/shaders/	The pipeline list and vertex shader table setup builds the shader cache from
tools/shader_list.py, tools/warm-up.ps1, config/warm-up/	Development tools that make that list: a scripted warm-up, its profile, list merging and checks
DEBUG_OPTIONS.md	Debug views, A/B switches of rendering fixes and diagnostics
tools/ (the rest)	Development tools; several assume the author's folder layout
guide/	The player guides linked above

Credits

• Pinyon Shift by arcanite24: the Forza Horizon recompilation whose native renderer, host UI and build scripts this project builds on (see THIRD_PARTY_NOTICES.md).
• ShiftGlue SDK, Pinyon Shift's fork of the ReXGlue SDK: the recompiler and runtime. This project uses a fork of it (branch fm4-static-recomp) with FM4's renderer fixes.
• Xenia, from which much of the runtime and GPU emulation in ReXGlue derives.
• fm4-recomp, an earlier FM4 recompilation on ReXGlue, which inspired this project.

AI use: code, scripts, documentation and reverse engineering of the game binary are AI-assisted.

License

The source in this repository is under the BSD 3-Clause License (LICENSE). Parts adapted from Pinyon Shift keep their own BSD 3-Clause notice (THIRD_PARTY_NOTICES.md). The license covers this project's code only: the game, its assets and any executable built from its translation are not covered, and must not be redistributed.

Legal

This is an unofficial fan project. It is not affiliated with, endorsed, sponsored or approved by Microsoft Corporation, Xbox Game Studios, Turn 10 Studios, or any other company or person that made, published or licensed Forza Motorsport 4, including the car manufacturers, track owners and other licensors whose names and brands appear in the game. Forza, Forza Motorsport, Xbox and Xbox 360 are trademarks of Microsoft Corporation; every other trademark belongs to its owner. This repository contains no game code, game assets, disc images, generated translation or prebuilt game executable: you need your own legally obtained copy of the game, and the executable is built on your computer.