WiiCompiled VR for the Steam Frame

Mario Kart Wii in VR on Valve's Steam Frame, running natively on SteamOS. It is built on WiiCompiled, the static recompilation of Mario Kart Wii to native code, and its VR fork WiiCompiled OpenXR VR. Nothing is emulated: your own disc is translated to C++, compiled for the Frame's ARM64 processor, and drawn through SteamVR.

Important

This project contains no Nintendo code, assets or game data. You need your own dump of the PAL disc. The game is built from it on your own machine, and nothing is uploaded or shared.

Warning

Beta. It plays on the Steam Frame at the panels' full 2160x2160 per eye, at 120 Hz, with the Frame's controllers and foveation that follows your eyes. Some images still double in races and on the HUD (see Known issues).

Contents: Quick start · Updating · Recommended settings · Controls · Known issues · Troubleshooting · Other ways to build · How it works · FAQ · Credits

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Quick start

One script takes you from your disc to the game in your Steam library. It downloads the newest release (currently frame-beta-3), extracts your disc, builds the game in an ARM64 container, installs it on the Frame and adds it to Steam. Releases hold only source code: the game is always built from your own disc.

Where to build

You can run the script on a Linux PC or on the Frame itself:

	On a Linux PC	On the Frame
First build	A few hours on an x86_64 PC (ARM64 is emulated), mostly building Dawn	Slower, and the Frame needs to stay on its charger
Updates	Run from the PC	Also from the Updates tab inside the game
Install option	--frame steamos@<frame-ip>	--frame local

Later builds reuse what the first one built, so updates usually take minutes.

You need

• a Steam Frame with Developer Mode on (Steam Settings → System → Enable Developer Mode, then set a user password);
• your own clean PAL RMCP01 disc of Mario Kart Wii, as an ISO, WBFS, RVZ, WIA, CISO, GCZ or NFS image, inside a .zip or .7z if you like, or as an extracted folder;
• about 20 GB free where the build goes (~/wiicompiled-frame, or another folder with --work-dir);
• to build on a PC: Linux on x86_64 or ARM64 with 16 GB of memory or more, on the same network as the Frame.

Note

Nobody here will tell you where to get the game, and links to game files are not tolerated.

1. Set up the container (PC only)

The build runs in a Debian ARM64 container. On an x86_64 PC, set up podman with ARM64 emulation:

sudo pacman -S --needed podman qemu-user-static qemu-user-static-binfmt   # Arch, CachyOS
sudo systemctl restart systemd-binfmt
podman run --rm --platform linux/arm64 docker.io/library/debian:trixie uname -m

The last command must print aarch64. On Debian or Ubuntu, install podman qemu-user-static binfmt-support instead. If podman complains about subordinate ids, run sudo usermod --add-subuids 100000-165535 --add-subgids 100000-165535 $USER and log in again. Docker works in place of podman. An ARM64 PC needs only podman or Docker, and the Frame already has podman.

2. Run the installer

From a PC, with your disc image and the Frame's address:

curl -fsSL https://raw.githubusercontent.com/mitch030504/Wiicompiled_VR_Frame/openxr-work/Launcher/steam-frame-install.sh \
    | bash -s -- --disc "/path/to/Mario Kart Wii.wbfs" --frame steamos@<frame-ip>

Or on the Frame, over SSH (ssh steamos@<frame-ip>) or in a Desktop Mode terminal:

curl -fsSL https://raw.githubusercontent.com/mitch030504/Wiicompiled_VR_Frame/openxr-work/Launcher/steam-frame-install.sh \
    | bash -s -- --disc "/path/to/Mario Kart Wii.wbfs" --frame local

--disc accepts any of these:

Extension	What it is
.iso	A plain disc image
.wbfs	Wii Backup File System image
.rvz	Dolphin's compressed image
.wia	Wii ISO Archive
.ciso	Compact ISO
.gcz	Dolphin's older compressed image
.nfs	A Wii game image from a Wii U
.zip, .7z	An archive holding one of the images above
a folder	An extracted disc, holding sys/ and files/

The script reads the format from the file's contents, so a renamed file works too.

The script checks that the disc is PAL RMCP01 before building, and stops on any other. If it stops for any reason, the same command picks up where it left off. From a PC, it asks for the Frame's password when it gets there. Steam must be running on the Frame for the last step, adding the game to the library.

Useful options (--help lists them all):

Option	What it does
--retro-rewind	Also builds Retro Rewind and adds it to Steam as RetroRewind. Its pack (about 4 GB) comes from Retro Rewind's own update server, as Wheel Wizard fetches it, along with the Retro-WFC payload online play needs. It shares WiiCompiled's settings.
--retro-rewind-pack DIR	Uses a RetroRewind6 folder you already have instead of downloading one.
--work-dir DIR	Where the build lives instead of ~/wiicompiled-frame, such as a folder on the Frame's SD card.
--jobs N	How many files compile at once. It defaults to a quarter of your memory in GB; lower it, to --jobs 2 for example, if the machine freezes.
--frame frame	With Frame Control set up, its SSH key answers to frame, so no password is asked.
--release TAG	Builds a given release instead of the newest.

Leaving out --frame only builds the game, into out in the work dir.

On the Frame the game goes to ~/devkit-game/WiiCompiled/. Installed from a PC, the disc goes to ~/wiicompiled/disc; with --frame local it stays in the work dir. Adding the game to Steam uses Valve's devkit tools in ~/devkit-utils, which Frame Control and Valve's Devkit Client put there; without them, the script says how to add it yourself.

3. Play

Start WiiCompiled from your library in the headset. Press the left shoulder button for the settings panel, and set the recommended settings on its VR tab.

Updating

From the machine you installed from

curl -fsSL https://raw.githubusercontent.com/mitch030504/Wiicompiled_VR_Frame/openxr-work/Launcher/steam-frame-install.sh \
    | bash -s -- --update

--update reuses the options you installed with, which the install saved in install.conf in the work dir. Add --work-dir if you used one; any option you pass wins over the saved one. It downloads the newest release, rebuilds only what changed and replaces the game on the Frame. When the Frame already has the newest release (and the newest Retro Rewind pack, if you use it), it says so and builds nothing. --check only says whether an update is available.

An install made with --frame local keeps a copy of the script in its work dir, so on the Frame ~/wiicompiled-frame/steam-frame-install.sh --update works too.

From inside the game

An install made on the Frame with --frame local adds an Updates tab to the settings panel. It shows the release you are running; Check for updates looks for a new one, and Update now builds it in the background while you keep playing (the game can stutter while it compiles). The tab shows each step and how far the build is, and tells you when to restart the game. If you close the game meanwhile, the update carries on and opens the game again when it is done. Keep the Frame on its charger while it runs.

The update runs as the systemd user service wiicompiled-update.service, at low priority so the game comes first. Installed from a PC, the tab says to update from the PC instead. Progress is not shown as Steam notifications, because Steam on the Frame does not display them.

Coming from frame-beta-2 or earlier

Older installs saved no options for --update to reuse. Update once with the full install command from step 2 (you can leave out --disc); from then on --update works. To get the in-game Updates tab, make that install on the Frame with --frame local.

Recommended settings

All of these are on the settings panel's VR tab and in ~/.local/share/WiiCompiled/Config.toml on the Frame. Quit the game before editing the file, since the game saves its settings to it.

Setting	Value	Why
[vr] render_scale	1.25	1.25 times SteamVR's recommended 1728x1728 is the panels' native 2160x2160, which the Frame renders in 9 to 11 ms a frame with medium foveation.
[vr] foveation	medium (default)	off shades every pixel and costs the most. See Known issues if images double.
[vr] repeat_frames	true (default)	Without it SteamVR halves the game's rate and fills in refreshes itself.
[vr] frame_interpolation_fps	0 (default)	In-between frames need 120 eye pairs a second, which made things worse on the Frame.
[vr] adaptive_resolution	false (default)	Experimental and not yet tried in a race on the Frame. When on, races drop to as little as 70% of render_scale while frames fall behind 60 FPS, and climb back once they keep up.
[video] resolution_multiplier	2	The game's own frame, which the eyes are made from. 4x is far too heavy for the Frame's GPU.

Keep SteamVR at 120 Hz. Motion Smoothing makes no difference to this game.

Controls

The Frame's controllers have their own bindings, so the left D-pad works:

Frame controller	Wii Remote mode	Gamepad mode
Right A	A	South (A)
Right B	C (look behind)	East (B)
Right trigger	B	Right trigger
Right stick up / down	1 / 2	Right stick
Left View	+ (pause)	Start
Left shoulder	Settings panel	North (Y)
Left D-pad	Wii Remote D-pad	D-pad
Left stick, left trigger	Nunchuk stick, Z	Left stick, left trigger
Grips, stick clicks, motion, aim	as on Quest Touch (OPENXR.md, Controllers)	as on Touch
Right X, Y, menu and shoulder	unbound	unbound

Known issues

• Doubled images in races and on the HUD, worst while racing and sometimes in one eye only. Foveation is the main suspect: the Frame's graphics driver draws the outer areas at lower resolution and scales them up, and each eye's foveation follows its own gaze. Try foveation Off if it bothers you, and report whether it helped.
• Foveation follows the right eye less well than the left. Eyes converging on near things (the HUD screen, the cockpit) are not yet corrected for.
• VR frame interpolation is not recommended on the Frame.
• The Quest app's Steam Frame version shows no picture in the Frame's Android layer (see How it works). Use this native build.

Troubleshooting

Collect everything at once. From a PC, run Launcher/frame-diagnostics.sh --frame steamos@<frame-ip> from the source (~/wiicompiled-frame/source after an install). It gathers the newest runs' logs and crash files, Config.toml, SteamVR's logs, the GPU driver and the system's state into one .tar.gz, and its summary.txt says how far the newest run got through the startup steps below.

Logs. Each run gets a folder under ~/.local/share/WiiCompiled/Logs/ on the Frame, with console.log and, after a crash, crash_sigsegv.txt. A working start logs, in order:

1. OpenXR initialized: runtime 'SteamVR/OpenXR';
2. Dawn will create its device through the runtime;
3. Fragment density maps: enabled;
4. OpenXR Vulkan swapchains ready ... same-queue native eye copies;
5. display refresh rate 120 Hz requested, then OpenXR session state -> FOCUSED;
6. OpenXR interaction profiles: left /interaction_profiles/valve/frame_controller_valve;
7. OpenXR eye gaze: available, then tracking.

The first one missing says where it stopped. Linux Vulkan OpenXR requires a Dawn built with Aurora's patches means the game was built by hand without --dawn-package.

Smoothness. With [diagnostics] openxr_logging = true in Config.toml, the log gets a pacing line every second. On the Frame:

cd ~/.local/share/WiiCompiled/Logs && grep -h "xr-diag\] 1.0" "$(ls -t | head -1)/console.log" | tail -5

A smooth race reads predicted-rate=120.0Hz, new=60 repeat=60 and late=0. Fewer than 60 new frames means the GPU is over budget: lower render_scale or resolution_multiplier.

Crashes. console.log names the crashed thread and gives a backtrace as module+offset. On the build machine, addr2line -f -C -e ~/wiicompiled-frame/source/native-build/WiiCompiled 0x<offset> turns an offset in WiiCompiled into a function name.

Builds. The log is build.log in the work dir, and its end says why a build stopped. A build that freezes the machine has run out of memory: run it again with a lower --jobs.

In-game updates. The Updates tab shows the step that failed. The full output is in the Frame's journal, journalctl --user -u wiicompiled-update.service, and the build's in build.log in the work dir.

Reporting problems

Open an issue saying what you did and what you saw (which eye, where in the picture, racing or in menus). Attach the diagnostics archive, or at least the run's console.log; for a build problem, the end of build.log. Problems that also happen on a PC or a Quest belong upstream, in WiiCompiled OpenXR VR.

Other ways to build

On a server

The script runs with Docker as well as podman, and much faster with more cores and memory. A machine that can't reach the Frame builds without --frame; give it more compiles at once if it has the memory, such as --jobs 8 for 32 GB:

curl -fsSL https://raw.githubusercontent.com/mitch030504/Wiicompiled_VR_Frame/openxr-work/Launcher/steam-frame-install.sh \
    | bash -s -- --disc "/path/to/Mario Kart Wii.wbfs" --jobs 8

Run it in tmux or screen so a closed SSH session doesn't stop it. Then copy ~/wiicompiled-frame/out and ~/wiicompiled-frame/disc to the Frame as in By hand, step 3.

On some hosts, such as Unraid 7 with kernel 6.18, binfmt_misc registrations are per container: tonistiigi/binfmt --install arm64 reports success, but Debian answers exec format error. Register qemu on the host instead, with the P flag the tonistiigi build of qemu expects (without it every program loses its first argument, and uname -m prints Linux):

docker create --name qemu-src tonistiigi/binfmt
docker cp qemu-src:/usr/bin/qemu-aarch64 /usr/local/bin/qemu-aarch64
docker rm qemu-src
echo ':qemu-aarch64:M::\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xb7\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/usr/local/bin/qemu-aarch64:POCF' > /proc/sys/fs/binfmt_misc/register
docker run --rm --platform linux/arm64 debian:trixie uname -m   # aarch64

Unraid keeps /usr/local/bin in memory, so repeat this after a reboot.

By hand

These are the steps the install script runs, for when you want to see or change one. Set up the container as in Quick start first. The commands use frame-beta-3; put the newest release's tag in its place.

1. Download the release and extract your disc

mkdir -p ~/wiicompiled/Wiicompiled_VR_Frame; cd ~/wiicompiled
curl -fL https://github.com/mitch030504/Wiicompiled_VR_Frame/archive/refs/tags/frame-beta-3.tar.gz \
    | tar -xz --strip-components=1 -C Wiicompiled_VR_Frame
curl -fL -o nodtool https://github.com/encounter/nod/releases/download/v2.0.0-alpha.10/nodtool-linux-x86_64
chmod +x nodtool
./nodtool extract "/path/to/Mario Kart Wii.wbfs" disc-extract
mkdir -p Wiicompiled_VR_Frame/Assets
cp disc-extract/sys/main.dol disc-extract/files/rel/StaticR.rel Wiicompiled_VR_Frame/Assets/

disc-extract must hold sys/ and files/ directly. Keep it: the game reads it while it runs. On an ARM64 machine, download nodtool-linux-aarch64 instead.

2. Build, inside an ARM64 container

podman run -it --name wiicompiled-frame --platform linux/arm64 -v ~/wiicompiled:/work docker.io/library/debian:trixie bash

Then, at the container's prompt:

apt-get update && apt-get install -y --no-install-recommends \
    ca-certificates curl git python3 xz-utils unzip file pkg-config g++ binutils libicu-dev zlib1g-dev \
    libvulkan-dev libx11-dev libx11-xcb-dev libxcb1-dev libxext-dev libxrandr-dev libxinerama-dev \
    libxcursor-dev libxi-dev libxss-dev libxtst-dev libxkbcommon-dev libwayland-dev wayland-protocols \
    libdecor-0-dev libegl-dev libgl-dev libgles-dev libdrm-dev libgbm-dev libasound2-dev libpulse-dev \
    libpipewire-0.3-dev libudev-dev libdbus-1-dev libusb-1.0-0-dev
cd /work/Wiicompiled_VR_Frame
Launcher/prepare-portable-tools.sh --arch aarch64 --destination /work/tools   # clang 22, CMake, Ninja
T=/work/tools/toolchain-aarch64/bin
curl -fsSL https://dot.net/v1/dotnet-install.sh | bash -s -- --channel 8.0 --install-dir /work/dotnet
Launcher/build-dawn-linux.sh --work-dir /work/dawn --cc $T/clang --cxx $T/clang++ \
    --cmake $T/cmake --ninja $T/ninja --jobs 4 2>&1 | tee -a /work/dawn.log
Launcher/local-build.sh --output-dir /work/out --cc $T/clang --cxx $T/clang++ --fuse-ld lld \
    --cmake $T/cmake --ninja $T/ninja --dotnet /work/dotnet/dotnet --parallel 4 \
    --openxr --dawn-package /work/dawn/package --headset steam_frame 2>&1 | tee -a /work/game.log
exit

• Dawn is done when it prints Patched Dawn for Linux ready, the game when it prints MKWCBUILD:OUTPUT=/work/out.
• --jobs 4 and --parallel 4 suit 16 GB of memory, since compiles take more memory under emulation. Use 8 with 32 GB.
• If it stops, podman start -ai wiicompiled-frame gets you back in. Run cd /work/Wiicompiled_VR_Frame; T=/work/tools/toolchain-aarch64/bin, then the step that stopped: both scripts resume.
• On the Frame or another ARM64 machine, start the container without --platform linux/arm64.

3. Install on the Frame

With Frame Control, drag ~/wiicompiled/out onto Send to Frame, name it WiiCompiled and keep Launches on WiiCompiled. That adds it to your Steam library, in ~/devkit-game/WiiCompiled/ on the Frame.

Then copy the disc over and tell the game where it is (Frame Control's SSH key answers to frame; use steamos@<frame-ip> otherwise):

ssh frame mkdir -p wiicompiled
scp -r ~/wiicompiled/disc-extract frame:wiicompiled/disc
ssh frame 'mkdir -p ~/.local/share/WiiCompiled && printf "[paths]\ndvd_root = \"/home/steamos/wiicompiled/disc\"\n" > ~/.local/share/WiiCompiled/Config.toml'

The last line replaces Config.toml, so run it on a first install only. Without Frame Control, scp -r ~/wiicompiled/out frame:wiicompiled/ and start ~/wiicompiled/out/WiiCompiled from a terminal in the Frame's Desktop Mode, with SteamVR running.

Updating by hand

Copy the new release's changed files over the old source, rebuild, and replace only the executable. rsync -c copies just the files whose content changed and stamps them with the current time, so the build recompiles exactly those; unpacking straight over the source would keep each file's older commit date, and changes could be skipped. Your Assets/ and build folders stay.

cd ~/wiicompiled
mkdir -p release-new
curl -fL https://github.com/mitch030504/Wiicompiled_VR_Frame/archive/refs/tags/frame-beta-3.tar.gz \
    | tar -xz --strip-components=1 -C release-new
rsync -rcE release-new/ Wiicompiled_VR_Frame/
rm -rf release-new
podman start -ai wiicompiled-frame
# in the container: cd /work/Wiicompiled_VR_Frame; T=/work/tools/toolchain-aarch64/bin, then the
# build-dawn-linux.sh and local-build.sh lines from step 2, then exit. Dawn is only rebuilt when the
# release changed its patches (the release notes say so).
scp ~/wiicompiled/out/WiiCompiled frame:devkit-game/WiiCompiled/WiiCompiled.new
ssh frame 'cd ~/devkit-game/WiiCompiled && chmod 755 WiiCompiled.new && mv -f WiiCompiled.new WiiCompiled'

Copying under a new name and moving it into place works even while the game is open.

How it works

• One GPU device. SteamVR's OpenXR runtime creates the Vulkan device that Dawn (the WebGPU layer under Aurora, the game's renderer) draws with, through Aurora's patches to Dawn (aurora-main/patches/dawn). Each eye is copied into SteamVR's swapchain on Dawn's own queue, so nothing has to be shared between devices. This is the PC's Vulkan backend (runtime/src/vr/openxr_vulkan_win32.cpp) compiled for Linux. Dawn is linked in statically, which is why the patched Dawn is built once on your machine (Launcher/build-dawn-linux.sh).
• Headset only. The game draws no desktop window, and is compiled for the Frame's Cortex-X4 cores (-mcpu=cortex-x4).
• Tuned for ARM64. The Frame's kernel uses 4 KiB memory pages, so the Steam Frame build skips the page-size check on every translated memory access; it checks once at startup and refuses to start if the size is ever different. Audio mixing uses NEON.
• Every refresh from the game. The game draws 60 frames a second. Given only those, SteamVR ran it at half rate and filled every other refresh itself, even with Motion Smoothing off. With [vr] repeat_frames, the pacing thread waits for the next frame until 1.5 ms before SteamVR's next wake, then submits the last frame again with the head pose it was drawn for, and SteamVR turns it to the current pose.
• Eye-tracked foveation. XR_EXT_eye_gaze_interaction gives the gaze, and Aurora picks a fragment density map centred on it, snapped to cells of about 3 degrees (aurora-main/lib/gfx/foveation.hpp), keeping up to 128 per eye. Each map has its own memory block, since sharing blocks crashed the game when a race restarted.
• 120 Hz. [vr] refresh_rate (120 on the Frame by default, 0 keeps the headset's own) is requested through XR_FB_display_refresh_rate. SteamVR only offers the rate set in its own settings.
• The Android version. The Quest app has a steamFrame flavour (android/Build-Quest.ps1 -Headset frame) for the Frame's Android layer, Lepton. It starts in VR there but shows no picture: the Android backend passes each eye between two GPU devices, and Lepton's graphics driver supports none of the ways to share images between them. The native build uses one device, which is why it is the one to play. docs/quest-port.md covers the Android build.

OPENXR.md documents every VR setting and the renderer in full.

What comes from where

This fork keeps everything WiiCompiled OpenXR VR has: menus on a virtual screen and races in stereo, a first-person cockpit with a steering wheel you can grab and turn, the settings panel in the headset, and Retro Rewind as its own translated game. The physics are identical to the original game, proven by ghosts that sync across the Wii, Dolphin and WiiCompiled.

On top of that it adds the SteamOS build, the install, update and diagnostics scripts and the Frame-specific rendering, and it carries fixes taken from WiiCompiled itself and from other forks: Linux TLS for online play, faster disc reads, safer settings saves, NEON audio mixing and more. CREDITS.md lists each with its author.

The PC (Windows) and Meta Quest builds are still in the source and unchanged; see OPENXR.md and docs/quest-port.md. To play on those, use upstream's WheelWizard VR rather than this fork.

WiiCompiled, WiiCompiled OpenXR VR, Wheel Wizard, Retro Rewind and this fork are developed independently, each with its own rules. Check each project's own README and CONTRIBUTING files.

FAQ

Is this an emulator? No. Everything is compiled to native ARM64 code before you press play. Nothing emulates a Wii processor or GPU while you play.

Can I download a ready-built game? No. The game is built from your own disc, and anything built from it can't be shared. The build is a one-time cost on your machine, and updates only rebuild what changed.

Which version of the game works? Clean PAL RMCP01 only. Other regions and modified discs are rejected.

Why not install the Quest app on the Frame? The Frame runs Android apps in Lepton, whose graphics driver can't pass images between the two GPU devices the Android version uses, so it shows nothing. The native build uses one device.

Can it run on other Linux ARM64 devices? Untested. Build by hand without --headset steam_frame and with --cpu for your processor to get a generic Linux VR build; it needs an OpenXR runtime with XR_KHR_vulkan_enable2. Unlike the Steam Frame build, it also works with memory pages larger than 4 KiB.

Credits

This fork stands on other people's work: WiiCompiled by patchzyy, WiiCompiled OpenXR VR by iChris4, the steering wheel and hand steering by heurazy, and fixes from heurazy's Wiicompiled_VR-PLUS, Chris Sotraidis's KartPad, DarthMDev, BlackAndBlue95's Strikers-WiiCompiled, rooklz and nx-mod's wiicompiled-nx. CREDITS.md says what came from whom, along with the tools and references used: aurora, Dawn, OpenXR, Dolphin, DolphinXR, nod, Retro Rewind, Wheel Wizard and Frame Control. The logo is by Inkwreck.

Bundled third-party components and their licenses are in THIRD-PARTY-NOTICES.md.

AI usage

AI coding tools were used to develop WiiCompiled and this fork. Translated output is checked against real hardware behaviour, and physics accuracy is proven by ghosts that sync across the Wii, Dolphin and WiiCompiled.

License

WiiCompiled is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License, version 3 as published by the Free Software Foundation.

WiiCompiled is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Any mkwii distribution making use of WiiCompiled must be licensed under GPL v3.0.

Not affiliated with, endorsed by, or associated with Nintendo. Mario Kart Wii is a trademark of Nintendo. No Nintendo intellectual property is contained in, distributed with, or obtainable through this project.