AnyaDance

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Want to use AnyaDance? Download a prebuilt Windows package from GitHub Releases. You do not need to clone or build this repository unless you want to develop AnyaDance or build it yourself.

AnyaDance is a Windows toolkit for driving and animating a VRChat avatar's full body — pose it by hand, drive it live, or play an MMD dance on it. At its core is a SteamVR/OpenVR virtual-device driver plus a companion UI (AnyaDance.exe) that streams to it. The driver exposes six virtual devices for VRChat full-body testing:

• HMD
• left controller
• right controller
• hip tracker
• left foot tracker
• right foot tracker

The driver receives pose and controller-input frames over UDP JSON on 127.0.0.1:39570. The companion executable, AnyaDance.exe, starts streaming a six-device T-pose at 60 Hz as soon as it opens.

AnyaDance is released as part of Project Anya, a larger project by Pipira. Project Anya itself is proprietary. Crediting Project Anya when you use or build on this driver is highly appreciated.

Disclaimer

This software is provided for legitimate, authorized testing and development only.

Feeding virtual devices or spoofed tracking into a live online game may violate that game's Terms of Service and can be detected by its anti-cheat system, which may result in the suspension or permanent ban of your account.

Registering the driver changes your SteamVR configuration: it activates AnyaDance's fully virtual HMD, controllers, and trackers and writes to steamvr.vrsettings. Registration creates a backup, and unregistering restores the original configuration. The virtual HMD continuously renders both eyes through the SteamVR compositor, which consumes additional GPU and CPU; raising the render resolution increases that load further.

You use this software entirely at your own risk. It is provided "as is" without warranty of any kind, and the authors accept no responsibility or liability for any consequences of use or misuse, including account bans or loss of access.

This project is not affiliated with or endorsed by VRChat, Valve, Steam, or SteamVR. All trademarks belong to their respective owners.

See DISCLAIMER.md for the full text. This is a safety acknowledgment, not an additional license condition. The companion UI asks you to acknowledge it on first launch.

Status

The code builds and its automated tests pass on Windows with Visual Studio 2022. The shipped tool registers the SteamVR driver, streams six virtual devices, and packages the driver bundle from the same build.

Requirements

• Windows 10 or newer
• SteamVR installed
• Microsoft Visual C++ Redistributable for Visual Studio 2015-2022 (x64)

Building from source additionally requires:

• Visual Studio 2022 or Visual Studio Build Tools with Desktop development with C++
• CMake 3.22 or newer
• Network access for the default first build, unless local dependency paths are supplied

Pinned dependencies:

• Valve OpenVR SDK 2.2.3
• Dear ImGui v1.90.9

Install A Release

1. Download AnyaDance-<version>-windows-x64.zip from the GitHub Releases page.
2. Extract the complete anyadance folder to a permanent location. Do not run the executable from inside the ZIP, and do not move or delete the folder while its driver is registered.
3. Run AnyaDance.exe, review and acknowledge the safety notice, then click Register Driver.
4. Click Restart SteamVR. SteamVR will start in fully virtual mode with the AnyaDance HMD, controllers, and trackers.

When finished, click Unregister Driver and restart SteamVR before moving or deleting the folder. This restores the SteamVR settings backup and returns SteamVR to real-device tracking. See Installation for details.

Build

.\scripts\build_driver.ps1

Outputs:

build\out\anyadance\AnyaDance.exe
build\out\anyadance\driver.vrdrivermanifest
build\out\anyadance\bin\win64\driver_anyadance.dll
build\out\anyadance\resources\...
build\out\anyadance\LICENSE
build\out\anyadance\NOTICE
build\out\anyadance\THIRD_PARTY_NOTICES.md
build\out\anyadance\DISCLAIMER.md
build\out\anyadance\TRADEMARKS.md
build\out\anyadance\README.md
build\out\anyadance\README.zh-CN.md
build\out\anyadance\README.ja.md
build\out\AnyaDance.zip

The UI ships inside the driver folder, so build\out\anyadance\ is one shippable bundle with the license/notices, and the build also zips it into build\out\AnyaDance.zip to hand to others directly. The exe registers its own folder as the SteamVR driver, so OpenVR finds driver.vrdrivermanifest and bin\win64\driver_anyadance.dll beside it. OpenVR loads the driver DLL from bin\win64\, with the manifest at the driver root.

To use local dependency checkouts:

.\scripts\build_driver.ps1 -OpenVRSdkRoot F:\deps\openvr -ImguiRoot F:\deps\imgui

Test

cmake --build build --config Release --target anyadance_tests
ctest --test-dir build -C Release --output-on-failure

The tests cover protocol validation, safety clamping, T-pose reset math, keyboard controls, mouse manipulation math, MMD remapping, .nya clip handling, and UDP log behavior.

Register

.\scripts\register_driver.ps1
.\scripts\restart_steamvr.ps1

register_driver.ps1 registers the driver and applies the fully virtual settings (virtual HMD, controllers, and trackers enabled), backing up steamvr.vrsettings to %LOCALAPPDATA%\AnyaDance\steamvr.vrsettings.backup first.

SteamVR must be restarted after registration changes and after rebuilding the driver DLL.

Unregister when you are done. Registration activates AnyaDance's fully virtual device set. See Unregister to restore your original SteamVR settings.

HMD Render Resolution

The virtual HMD renders at 1920x1080 per eye by default, which keeps the SteamVR compositor's load modest. Advanced users can raise it without rebuilding the driver by overriding two settings keys.

Edit the global steamvr.vrsettings (at <Steam>\config\steamvr.vrsettings) and add or extend the driver_anyadance section:

"driver_anyadance": {
    "headset_render_width": 3840,
    "headset_render_height": 2160
}

Then restart SteamVR (.\scripts\restart_steamvr.ps1). 3840x2160 is 4K. Any aspect ratio works (for example, match your monitor's) — the projection adapts to the configured render resolution, so the image is not stretched. Higher resolutions cost roughly the square of the scale in GPU render time — 4K is about four times 1080p.

Values set in steamvr.vrsettings win over the driver defaults in resources\settings\default.vrsettings. The same section also exposes headset_window_width, headset_window_height, headset_window_eye_mode, and headset_window_preserve_aspect for the desktop mirror window; see docs/device-model.md.

The driver also reports processed UDP commands over a loopback-only multicast group by default. The group and port are configurable in the same section:

"driver_anyadance": {
    "command_log_enabled": true,
    "command_log_multicast_group": "239.255.39.71",
    "command_log_port": 39571
}

The UI's Monitor driver commands switch starts off and remembers your choice across launches. It joins or leaves the default group immediately. Multiple local applications can subscribe simultaneously. Run .\scripts\listen_driver_log.ps1 for a reference listener, or add -Validate -ListenerCount 3 to verify three independent receiver processes. To subscribe from your own application, see Writing A Receiver for the socket setup, a worked example, and what to check when nothing arrives; docs/protocol.md covers the packet schema and delivery behavior.

Run The Test UI

.\build\out\anyadance\AnyaDance.exe

The UI:

• starts 60 Hz UDP streaming automatically
• continues streaming while minimized or unfocused
• sends a final neutral-input frame on normal exit
• keeps the UDP log in English and can hot-toggle driver command monitoring; while monitoring is active, driver processing reports show commands from the UI and third-party UDP senders without duplicate successful-send rows
• shows hover or pinned row detail with three payload actions: Copy (the raw request body), Copy resend command (a runnable PowerShell UDP one-liner), and Resend (replays the exact datagram from the UI over its own socket)
• can register/unregister its own folder as the SteamVR driver and restart SteamVR (with a confirmation) from its own buttons
• has an Always on top checkbox that pins the window above other windows; the choice is remembered between runs
• can play an MMD dance on the fly: the Dance (MMD) button opens a dialog to pick a .vmd motion and a .pmx/.pmd model, then Analyze and Play stream the dance onto the six devices (see docs/mmd-dance.md)
• can save and restore poses and dances as .nya clips: Save Pose / Load Pose in the main window capture and restore the current pose, and the Dance dialog can Save .nya of an analyzed dance and Load .nya to play it again without re-solving
• supports English, Simplified Chinese, and Japanese UI strings through src/ui/localization.*
• shows the build version in the Windows title bar and footer; GitHub release builds use the exact release tag

Key bindings:

WASD  left joystick movement
Q/E   right joystick turn
Space right A while held
M     right B while held
V     left A while held
Z     left trigger while held
X     right trigger while held

Mouse manipulation uses the six device boxes. The capture panel and boxes resize with the UI window. The HMD box allows rotation, plus vertical (Y) movement with a right mouse drag; a left+right chord provides the same vertical gesture. Other devices use left mouse drag for local X/Y movement, middle mouse drag for rotation, and right mouse drag for depth movement. Device Y is capped at 25 m, and only the HMD has a floor at 0 m; the other five devices may go below the ground plane down to -30 m. The HMD/Global frame radio buttons choose whether manipulation uses the HMD yaw basis or fixed world axes. The hand and foot pair mirror checkboxes use the same frame setting: HMD mode mirrors across the HMD-yaw YZ plane, and Global mode mirrors across world axes centered on the HMD position. The mouse wheel opens and closes both hands' fingers. Hold a number key while scrolling to bend a single finger: 1-5 are the left hand from pinky to thumb, 6-0 are the right hand from thumb to pinky (so 5/6 are the thumbs and 1/0 the pinkies). Each finger is clamped to [0, 1], and scrolling all the way in one direction resets every finger to fully open or fully closed. Closing every finger on a hand into a fist (all bends near full) presses that hand's grip; releasing any finger releases it, which drives VRChat's grab.

Dragging the empty area of the body panel acts as the right thumbstick: the press point is the stick center, and dragging deflects it within ±1 on each axis, returning to neutral on release. This is meant for navigating the right-hand quick menu (opened by holding M). The empty area also manipulates the whole rig at once: a middle mouse drag rotates all six devices (yaw/pitch) about the HMD position, a middle+right drag rolls them about the same pivot, and a right mouse drag moves the whole rig vertically while preserving its shape, stopping on the way down when the HMD reaches 0 m. Rig rotation uses the same HMD/Global frame setting as the per-device gestures.

MMD Dance

The Dance (MMD) button plays an MMD dance on the six virtual devices live in memory. Blender + MMD Tools solves the .vmd motion against a model you supply (PMX/PMD), and the UI does a small remapping onto the hardcoded rig and streams it at 60 Hz. Pick the VMD and model in the dialog, hit Analyze, then Play. Use Advanced to set Blender and MMD Tools paths for custom installs; the UI remembers those paths.

Requirements: Blender and the MMD Tools add-on (both auto-detected), plus your own model. MMD models are third-party works with their own licenses. See docs/mmd-dance.md for details, parameters, and runtime behavior.

Once a dance is analyzed, Save .nya writes the result to a clip file. Load .nya reads one back and enables Play immediately — loading skips both the Blender solve and the remap, so a saved dance plays instantly.

Clip files (.nya)

A .nya file is a small JSON clip of device-level frames — the six device poses plus per-hand finger bends — ready to stream with no further conversion. The format is the same for poses and animations: a pose is a one-frame clip (played as a held loop of that single frame) and an animation (such as a saved MMD dance) is many timed frames. Loading clamps device Y to 0–25 m for the HMD and -30–25 m for the other five devices, and finger bends to [0, 1].

Safety And Liveness

All six devices share a 25 m Y ceiling. Only the HMD has a floor, at 0 m — it is the play-space head, so putting it below the ground plane puts the view underground. The other five devices legitimately go below it (a foot passing under the floor plane, a hip in a floor move) and are bounded only by the shared ±30 m position range. The UI clamps before serialization and the native driver clamps again after packet validation.

All six devices start connected and valid at neutral poses. Accepted packets update the latest pose and controller inputs. If packets stop, SteamVR continues to see each device connected, valid, and TrackingResult_Running_OK at its last accepted pose.

Protocol Overview

• UDP to 127.0.0.1:39570
• UTF-8 JSON
• version must be 1
• fire-and-forget datagrams
• accepted datagrams are smaller than 8192 bytes
• quaternion order is XYZW
• recognized device IDs are hmd, left_controller, right_controller, hip, left_foot, right_foot

See docs/protocol.md for the full protocol.

Unregister

.\scripts\uninstall.ps1

Unregistering restores the original SteamVR configuration. While registered, SteamVR uses the six-device AnyaDance virtual rig. Unregistering restores the settings backup created during registration.

uninstall.ps1 saves a recovery snapshot, removes the driver entry, restores steamvr.vrsettings from the registration backup when available, verifies removal, restarts SteamVR, and leaves the AnyaDance application files in place.

You can also unregister from within the UI using the Unregister Driver button, which uses the same recovery files and prompts to restart SteamVR.

Uninstall

1. Unregister the driver (see Unregister above) and restart SteamVR so real devices are restored.
2. Delete the AnyaDance folder you extracted.
3. Optionally delete the UI's saved state from AppData:
   • %LOCALAPPDATA%\AnyaDance\ui_state.ini — saved preferences (window size, paths, always-on-top, etc.)
   • %LOCALAPPDATA%\AnyaDance\steamvr.vrsettings.backup — the SteamVR settings backup made during registration (removed automatically on unregister)
   • %LOCALAPPDATA%\AnyaDance\registered_driver_path.txt — the path recorded at registration so unregister can find the bundle even if it moved (removed automatically on unregister)

If you skip step 1 before deleting the folder, SteamVR will still reference the (now missing) driver path. Run uninstall.ps1 from a copy of the scripts folder, or remove the driver entry manually from %LOCALAPPDATA%\openvr\openvrpaths.vrpath.

License

AnyaDance is open source, licensed under the Apache License, Version 2.0.

Licensed under the Apache License, Version 2.0. See LICENSE and the NOTICE attribution file. Redistributions must preserve the NOTICE contents and mark any modified files. Bundled third-party components keep their own licenses; see THIRD_PARTY_NOTICES.md.

Media ownership, licensing, and the separate terms that apply to the EmoteLab dance GIF are documented in ASSETS.md.

See TRADEMARKS.md for the AnyaDance and Project Anya branding notice.