YAPYAP Head Tracking

An unofficial head tracking mod for YAPYAP that moves the view with your head while your mouse or controller keeps aiming, driven by a webcam, phone, or any OpenTrack compatible tracker, with no VR headset required.

• Decoupled look and aim - head movement rotates the view while your normal controls keep aiming.
• 6DOF tracking - yaw, pitch and roll plus positional lean, peek and duck.
• Works with any OpenTrack compatible tracker - free options available for PC, iOS and Android

• YAPYAP on Steam.
• OpenTrack or another tracking source that can send OpenTrack UDP data.
• Windows 10/11, 64-bit.
• BepInEx 5 x64, included in the standalone installer and provisioned by Lopari.

Download Lopari, choose YAPYAP, and click Play with head tracking.

1. Download the ZIP ending in -installer.zip from the latest release.
2. Extract it anywhere.
3. Double-click install.cmd.
4. Configure your tracker using the setup below.
5. Launch the game.

If the installer cannot find your game, set YAPYAP_PATH to the game folder or pass the game folder as the first argument:

$env:YAPYAP_PATH = "D:\Games\YAPYAP"
.\install.cmd
.\install.cmd "D:\Games\YAPYAP"

1. Install BepInEx 5 x64 into the YAPYAP game folder.
2. Run the game once so BepInEx creates its folders.
3. From the installer ZIP's plugins\ folder, copy YapyapHeadTracking.dll, CameraUnlock.Core.dll, and CameraUnlock.Core.Unity.dll into YAPYAP\BepInEx\plugins\. If you have the Nexus ZIP instead, extract it into the game folder; it already contains the BepInEx\plugins\ layout.
4. Configure your tracker using the setup below, then launch the game.

After launch, YAPYAP\BepInEx\LogOutput.log should contain YAPYAP Head Tracking initialized.

The mod accepts OpenTrack UDP pose data on port 4242. Use the webcam, phone, or hardware route below that matches your tracker.

1. Install OpenTrack.
2. Pick a tracker under Input, using the notes below.
3. Set Output to UDP over network, host 127.0.0.1, port 4242.
4. Press Start. Tracking and the game can start in either order.

OpenTrack ships a neuralnet tracker input that reads a plain webcam. Select it under Input, pick your camera in its settings, and use the output settings above. How well it tracks depends on your camera and your lighting, so try it before buying anything.

A phone app can reach the mod directly if it sends OpenTrack UDP pose data. Point it at this PC's IP address (run ipconfig to find it) on port 4242. Check that the app's output supports the OpenTrack UDP protocol. Headcam is my own free phone tracker; it filters on-device and can send directly to the mod.

Sending direct works when the app filters its own signal on the device. The mod has separate local and remote smoothing settings. If the view shakes while your head is still, point the app at OpenTrack's UDP over network input on some other port, say 5252, and let OpenTrack's filters and curves clean it up before its output forwards to 127.0.0.1:4242.

Anything arriving from outside 127.0.0.0/8 counts as a remote connection and is smoothed with RemoteSmoothing rather than LocalSmoothing. That includes a tracker on this very PC that sends to the machine's own LAN address, because the mod reads the source address and not the machine.

If your device has an OpenTrack input driver, select it under Input and use the same output settings. OpenTrack's own Input list is the authority on what it can read; the mod only ever sees what OpenTrack sends.

Centre in your tracker app, using OpenTrack's Center bind or Headcam's CENTER button. The mod keeps no centre of its own. If the view sits off to one side, centre it in the tracker.

The Nav-cluster and Chord columns are equivalent. Use whichever your keyboard has.

Page Up / Ctrl+Shift+G cycles tracking mode:

1. Full tracking: rotation and position.
2. Rotation only: positional tracking disabled.
3. Position only: rotational tracking disabled.

The next press returns to full tracking.

Page Down / Ctrl+Shift+H switches between horizon-locked yaw (the default) and yaw around the camera's current up-axis.

The tracking mode and the yaw mode you pick are saved to CameraUnlock.ini and are what the next start begins with. End turns head tracking on and off for this session only; whether it is on at the next start is the EnableOnStartup setting.

These are the default keys. Each action reads a list of keys from CameraUnlock.ini (ToggleKey, CycleTrackingModeKey, YawModeKey), and any key in the list fires it, so you can add, rebind or remove any of them, the chords included.

The game's crosshair follows your aim while head tracking turns the view. It has no setting.

There is no recenter key in the mod. Centre in your tracker app.

The mod reads its settings from BepInEx\config\CameraUnlock.ini in the game folder, and creates the file when it starts and finds none. Edit it with any text editor.

A setting set to default takes its value from Defaults.ini, which every head tracking mod that keeps its settings in CameraUnlock.ini reads. Head tracking mods that keep their settings in another file do not read it. Writing a value in place of default changes that setting for this game only. When the mod saves a setting that a hotkey changed in game, it writes the new value in place of default, so that setting no longer follows Defaults.ini in this game until you set it to default again.

Defaults.ini is %AppData%\CameraUnlock\Defaults.ini on Windows; $XDG_CONFIG_HOME/CameraUnlock/Defaults.ini on Linux, or ~/.config/CameraUnlock/Defaults.ini where XDG_CONFIG_HOME is not set, under Wine and Proton too; and ~/Library/Application Support/CameraUnlock/Defaults.ini on macOS. The mod's log, where it writes one, names the file it read.

When the mod starts and finds no Defaults.ini, it creates one holding the built-in values, unless Windows runs the game as a packaged app, or the game runs on Linux or macOS without Wine or Proton. The mod never changes Defaults.ini after that. Edit it with any text editor.

On Linux and macOS without Wine or Proton, this version reads its settings and saves none: it creates no CameraUnlock.ini and a change made in game lasts until the game closes.

BepInEx's ConfigurationManager does not list these settings.

The built-in value of each setting set to default below:

• UdpPort=4242
• EnableOnStartup=true
• WorldSpaceYaw=true
• RotationEnabled=true
• LocalSmoothing=0.0
• RemoteSmoothing=0.15
• PositionEnabled=true
• PositionLimitX=0.3
• PositionLimitY=0.2
• PositionLimitYDown=0.2
• PositionLimitZ=0.4
• PositionLimitZBack=0.1
• ToggleKey=End, Ctrl+Shift+Y
• CycleTrackingModeKey=PageUp, Ctrl+Shift+G
• YawModeKey=PageDown, Ctrl+Shift+H

With every setting at its default, the file reads:

; YAPYAP head tracking settings.
; Comments start with ; and go on their own line. Text after a value is part of the value.
; Hotkeys are key names such as End, PageUp or Ctrl+Shift+Y. Separate several with commas; leave empty for none.
; A setting set to default takes its value from Defaults.ini, which every head tracking mod
; that keeps its settings in CameraUnlock.ini reads: %AppData%\CameraUnlock\Defaults.ini on
; Windows, $XDG_CONFIG_HOME/CameraUnlock/Defaults.ini (normally ~/.config/CameraUnlock) on
; Linux, under Wine and Proton too, and ~/Library/Application Support/CameraUnlock/Defaults.ini
; on macOS. The log names the file it read. Write a value instead of default to change that
; setting for this game only.

[CameraUnlock]
; Written by the mod. Leave this section in place.
ConfigFormat=1

[Network]
; UDP port the mod receives tracker data on (OpenTrack protocol).
UdpPort=default

[General]
; true: head tracking is on when the game starts. ToggleKey turns it on and off.
EnableOnStartup=default
; true: yaw turns around the world's up axis. false: around the camera's own up axis.
WorldSpaceYaw=default
; true: turning your head turns the view.
; Tracking mode at startup, with PositionEnabled. The mode hotkey changes both.
RotationEnabled=default

[Smoothing]
; Smoothing when the tracker runs on this PC. 0 is the least, 1 the most.
LocalSmoothing=default
; Smoothing when the tracker is another device on the network, such as a phone.
; 0 is the least, 1 the most.
RemoteSmoothing=default

[Position]
; true: moving your head moves the view.
; Tracking mode at startup, with RotationEnabled. The mode hotkey changes both.
PositionEnabled=default
; How far, in metres, leaning left or right can move the view.
PositionLimitX=default
; How far, in metres, raising your head can move the view.
PositionLimitY=default
; How far, in metres, lowering your head can move the view.
PositionLimitYDown=default
; How far, in metres, leaning forward can move the view.
PositionLimitZ=default
; How far, in metres, leaning back can move the view.
PositionLimitZBack=default

[Hotkeys]
; Turns head tracking on and off.
ToggleKey=default
; Changes the tracking mode: rotation and position, rotation only, position only.
CycleTrackingModeKey=default
; Switches yaw between the world's up axis and the camera's own (WorldSpaceYaw).
YawModeKey=default

[Notifications]
; true: show whether head tracking is on, and its hotkeys, when the game starts.
ShowStartupNotification=true
; true: show a message when tracker data starts or stops arriving.
ShowConnectionNotifications=true

Smoothing covers both rotation and position. Which of the two values applies is decided from the packet source address: loopback uses LocalSmoothing, other addresses use RemoteSmoothing. Changing sender takes effect without restarting the game. Edit filtering and response curves in your tracker first.

Start with YAPYAP\BepInEx\LogOutput.log. The mod logs initialization, the UDP port, and when a tracker connection is established or lost.

Mod not loading

• Confirm all three DLLs listed under Manual Installation are in YAPYAP\BepInEx\plugins\.
• For a manual install, check that you installed BepInEx 5 x64.
• Check YAPYAP\BepInEx\LogOutput.log for YAPYAP Head Tracking.
• Re-run install.cmd if BepInEx folders are missing.

No tracking response

• Confirm OpenTrack is running and output is UDP to 127.0.0.1:4242.
• Check YAPYAP\BepInEx\LogOutput.log for OpenTrack connection established.
• Press End or Ctrl+Shift+Y if tracking is disabled.
• For a direct phone connection, check the PC's LAN address, port 4242, and Windows Firewall access for the game.

Tracking stops in menus or overlays

By design: tracking is suppressed in menus, settings, chat, and spell wheels, and when the game loses input focus. Return to gameplay to resume tracking.

Config changes do not apply

• Close the game, edit BepInEx\config\CameraUnlock.ini, then relaunch.
• Make sure nothing follows the value on the line: text after a value is part of the value. YAPYAP\BepInEx\LogOutput.log names each line the mod could not read and the value it used instead.

Jittery / unstable tracking

• Increase OpenTrack smoothing, or the mod's RemoteSmoothing (phone/network tracker) or LocalSmoothing (tracker on this PC) setting.
• Use a stable webcam, phone mount, or headset connection.

Wrong rotation axis / yaw feels wrong when looking up or down at extreme angles

• Toggle between world-locked and camera-local yaw with Page Down or Ctrl+Shift+H. World-locked (default) keeps yaw horizon-stable no matter where you are pitched; camera-local follows the camera's current up-axis.
• Centre your view in your tracker app (OpenTrack's Center bind or Headcam's CENTER button).
• If pitch feels inverted, invert it in OpenTrack's output mapping. The mod has no invert or sensitivity settings; the axis corrections it needs are applied internally.

Known limitations

• Positional lean is limited by the configured distances but does not check walls. If leaning clips the view through geometry, reduce the position limits or select rotation-only mode with Page Up / Ctrl+Shift+G.
• Crosshair compensation accounts for head rotation, not parallax from positional lean. Use rotation-only mode if that offset is distracting.

For a standalone installation, download the new installer ZIP, extract it, and run its install.cmd. Your CameraUnlock.ini is preserved. For a manual installation, replace the three plugin DLLs with those from the new release and keep your config files.

For a standalone installation, run uninstall.cmd. This removes the mod DLLs and leaves CameraUnlock.ini in place. BepInEx is only removed if the installer put it there; /force also removes a pre-existing BepInEx installation. Removing BepInEx removes its plugins and config folder too. If other mods use it, use the manual removal steps below.

For a manual uninstall, remove YapyapHeadTracking.dll, CameraUnlock.Core.dll, and CameraUnlock.Core.Unity.dll from YAPYAP\BepInEx\plugins\. Keep the shared CameraUnlock DLLs if another mod uses them. You can also delete YAPYAP\BepInEx\config\CameraUnlock.ini to remove your settings. Keep BepInEx if other mods need it.

Prerequisites: Windows, .NET SDK 8, Git and pixi. pixi run package runs setup, restore and build before packaging, using the same task as CI. Setup compiles the Unity reference assemblies from the stub sources in the cameraunlock-core submodule and takes the BepInEx references from the vendored loader archive.

git clone --recursive https://github.com/itsloopyo/yapyap-headtracking.git
cd yapyap-headtracking
pixi run package

The packages are written to release/ as YapyapHeadTracking-v<version>-installer.zip and YapyapHeadTracking-v<version>-nexus.zip.

• Discord: Loop's Head Tracking Hangout - setup help, bug reports, and new-release announcements
• Lopari - free Windows launcher with one-click install and launch for the released head-tracking mods
• Headcam - free app that turns your iPhone or Android phone into the head tracker

MIT License - see LICENSE for details. Third-party licence texts and attribution are in THIRD-PARTY-NOTICES.md.

• maisonbap - developer and publisher of YAPYAP.
• BepInEx - Unity plugin framework.
• OpenTrack - head tracking software.
• CameraUnlock.Core - shared head tracking library.

This mod is not affiliated with, endorsed by, or supported by maisonbap. Use at your own risk.