A VRChat OSC tool to move a player in the direction of a stretched Physbone.
For leashes, tails, or even hand holding!

Download & Setup

Download the latest version of OSCLeash from releases.
This app does not provide a model for a Leash at this time.

Setup Steps (Click the Arrow!)

1. Grab the prefab (OSCLeash.prefab) from releases and drop it into your Unity project.
2. Place the prefab on the root of your model. (NOT a child of armature) Don't break prefab!
3. Select the Leash Physbone object and assign the Root Transform of the Physbone to the first bone of your leash.
4. Select the Compass object and assign the source of the Position constraint to the first bone of your leash.
5. You can find Aim Needle as a child of compass. Assign the source of the Aim Constraint to the last bone of your leash.
6. (Optional) You can animate the compass object off for remote users using IsLocal. Saves some performance!
7. Enable OSC in VRChat settings. (Or reset OSC if you updated an avatar!) ~ Tutorial
8. Run the OSCLeash app and get pulled about!
9. Visit Config and fine tune settings for your taste

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If you're having issues, make sure to see the FAQ section.
If all else fails, feel free to reach out in the #OSC-Talkin channel in my Discord

Config

After running OSCleash at least once, an OSCLeash.json file will be generated.
The default install location of OSCLeash is %LocalAppData%\Programs\OSCLeash
You can open the json file in your favorite text editor and fine tune your OSCLeash.

Table of Configation settings

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Value	Info	Default
IP	Address to send OSC data to	127.0.0.1
ListeningPort	Port to listen for OSC data on	9001
Sending port	Port to send OSC data to	9000
RunDeadzone	Minimum Stretch % to cause running	0.70
WalkDeadzone	Minimum Stretch % to start walking	0.15
StrengthMultiplier	Multiplies speed values but they can't go above (1.0)	1.2
UpDownCompensation	% of compensation to apply for Up/Down angles	1.0
UpDownDeadzone	Stops movement if pull angle is above/below this. 1.0 Disables	0.5
TurningEnabled	Enable turning functionality	false
TurningMultiplier	Adjust turning speed	0.80
TurningDeadzone	Minimum Stretch % to start turning	0.15
TurningGoal	Goal degree range for turning. (degrees, 0-144) (0° to 144°)	90
ActiveDelay	Delay in seconds between OSC messages while active	0.02
InactiveDelay	Delay in seconds for OSCLeash while not in use	0.5
Logging	Logging for Directional compass inputs	false
XboxJoystickMovement	Alt movement method for an old bug. Removing eventually	false
PhysboneParameters	A list of Physbones that are leashes	see below
DirectionalParameters	A list of contacts to use for direction calculation	see below

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Default Config.json

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{
        "IP": "127.0.0.1",
        "ListeningPort": 9001,
        "SendingPort": 9000,
        "RunDeadzone": 0.70,
        "WalkDeadzone": 0.15,
        "StrengthMultiplier": 1.2,
        "UpDownCompensation": 1.0,
        "UpDownDeadzone": 0.5,
        "TurningEnabled": false,
        "TurningMultiplier": 0.80,
        "TurningDeadzone": 0.15,
        "TurningGoal": 90,
        "ActiveDelay": 0.02,
        "InactiveDelay": 0.5,
        "Logging": false,
        "XboxJoystickMovement": false,
        
        "PhysboneParameters":
        [
                "Leash"
        ],
        "DirectionalParameters":
        {
                "Z_Positive_Param": "Leash_Z+",
                "Z_Negative_Param": "Leash_Z-",
                "X_Positive_Param": "Leash_X+",
                "X_Negative_Param": "Leash_X-",
                "Y_Positive_Param": "Leash_Y+",
                "Y_Negative_Param": "Leash_Y-"
        }
}

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Physbone Parameters

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This is a list of all the Physbones you're using with OSCLeash.

        "PhysboneParameters":
        [
            "Leash",
            "Leash2",
            "Leash3"
        ],

OSCLeash listens for the _IsGrabbed and _Stretch parameters for every listed leash.

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Multiple Leashes

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This requires an understanding of Physbones Parameters, Animations, and Constraints.

• Add a new source to Compass and Aim Needle for each extra leash. 0 Weight by default
• Depending on which leash _IsGrabbed, animate the weights to match the Grabbed leash.

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Turning Functionality

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⚠️ Motion sickness warning ⚠️

If you want to enable this feature, set TurningEnabled to True.
Currently Supports North, East, South, & West

If you had a leash up front and you want to turn to match the direction it's pulled from (EG: a Collar with the leash on the front) Set set the parameter on your Leash Physbone and config to Leash_North.

Config File

        "PhysboneParameters":
        [
            "Leash_North"
        ],

We parse the direction to control turning so "Tail_South" would work.
Whenever this leash is grabbed and pulled past the deadzone it will begin to turn.
It will continue to turn until it is greater than the TurningDeadzone value.

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Nerd Stuff

Here's the simplified logic of the system.

if LeashDirection == "North" and Z_Positive < TurningGoal:
    TurningSpeed = ((X_Negative - X_Positive) * LeashStretch * TurningMultiplier)

Extra stuff for nerds!

How OSCLeash works

Step 1: Get Leash Physbone parameters

We receive the Leash_Stretch and Leash_Grabbed parameters.
If Leash_Grabbed becomes true, we begin reading Leash_Stretch

We'll use these values in this example:

Leash_IsGrabbed = True
Leash_Stretch = $0.95$

Step 2: Gather Directional Contact values

4 Contacts (Blue) surround a object with an aim constraint and a contact at the tip. (Yellow)

Based on where the constraint is aimed, it will give us 4 values.

If it was pointing South-South-West, we would get:

Leash_Z+ = $0.0$
Leash_Z- = $0.75$
Leash_X+ = $0.0$
Leash_X- = $0.25$

Step 3: Math

Math is fun. Add the negative and positive contacts & multiply by the stretch value.

(Z_Positive - Z_Negative) * Leash_Stretch = Vertical
(X_Positive - X_Negative) * Leash_Stretch = Horizontal

So our calculation for speed output would look like:

$(0.0 - 0.75) * 0.95 = -0.7125$ = Veritcal
$(0.0 - 0.25) * 0.95 = -0.2375$ = Horizontal

Step 4: Outputs

If either value is above the walking deadzone (default 0.15) we start outputting them instead of 0.
If either value is above the running deadzone (0.7) we tell the player to run (x2 speed)

All movement values are relative to the VRC world's movement speed limits.
So we'd be moving at $142.5$% speed south and $47.5$% speed to the West.

If the values are below the deadzones or _IsGrabbed is false, send 0s for the OSC values once to stop movement.

FAQ

Click to Expand

Q: OSCLeash.exe is removed by my antivirus.
A1: This is a false positive I can't really fix. You'll need to add an exclusion.
A2: Try out the MSI version if you're having trouble with the EXE or build it yourself.

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Q: OSCLeash always says Started, awaiting input
A1: Manually Reset OSC by deleting the OSC and OSC.bak folders at C:\Users\(Your username)\AppData\LocalLow\VRChat\VRChat
A2: Did you do avatar setup correctly? Make sure your leash physbone matches your config.
A3: This could potentially be a firewall issue, but before that, double check your avatar, pleaaaase.

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Q: OSCLeash says grabbed but I don't get moved.
A1: This can happen if your leash physbone does not have any stretch.
A2: Make sure self interaction is enabled, it's needed for the direction calculation.

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Q: The direction OSCLeash pulls is not accurate
A1: Is your physbone too angle limited or short? If it can't move it can't get an accurate location.
A2: If your scaling up very large, scale down the Compass object ~ contacts have a max size.

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Q: How can I run OSCLeash with my other OSC apps?
A: Try out an OSC Router, like OSC Switch. I'll add OSCquery support when it whitelists parameters
(Or when I get around to a performant C# rewrite)

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Q: My Question/Issue isn't answered above
A: Discord or Git Issue

Future Plans/Goals

• Simple dOSC app version
• Performant C# Rewrite
  • Turns out python isn't great for really fast stuff?
  • Maybe even C++ if masochistic enough.
• OSCQuery Support (When whitelisting is fixed)
• Anchoring leash to a point in world space when posed.
• Using a player Contact Tracker to follow automatically.
• Y axis movement via an OVRAS API

Running from Source

For those that want to, you can run OSCLeash without an installer or exe.

• Clone the repo
• CD into the directory
• Run pip install -r requirements.txt
• Run OSCLeash.py

Credits & Liscenses

• App Rope Icon | Game-icons.net under CC by 3.0
• @ALeonic is responsible for a majority of v2 (Threading is scary!)
• @FrostbyteVR walked me through the proccess of making v1
• Someone else did this but it was a closed source executable