156 syllabus      site index      3D artists      past student work        DMA

Unity VR with Maya Legacy Dynamics

Magic Mirror reflection

Tutorial to create an animated bouncing ball using legacy dynamics, bake the animation, then import into Unity. The newer Ncloth dynamics do not port motion into Unity because the shape of the cloth changes with every frame of animation. Legacy dynamics do not change their shape making it easier to port into Unity.

In Maya:
Create->Polygon Primitives->Soccer Ball

Move the ball above the Y axis

Add Legacy dynamics
Switch to the FX Module

Select the ball
Choose Fields/Solvers->Create Active Rigid Body
In the Channel Editor, input Initial Spin X 1   (Ncloth does not have this feature.)

Add gravity
Select the ball
Choose Fields/Solvers->Gravity

Add a ground object
Create Polygon Primitives->Plane
Scale it up a bit
Select the plane
Choose Fields/Solvers->Create Passive Rigid Body

Hit the play arrow on the time slider. timesliderplay.jpg

You may need to make the Time Slider animation End Time longer. Unity uses the Time Slider to determine the length of the animation.

Bake the Simulation for Unity etc
Switch the Menu to Animation in the top left corner of the Maya window

Select the ball.
Choose Key->Bake Simulation
The default settings will create keys for rotation and translation for every frame, using the time slider.

Select Edit->Delete by Type->Rigid Bodies

Select Edit->Delete by Type->Static Channels to clean up extra unused channels

Delete the Plane, and the gravityField

In Unity:
Import SteamVR

Type SteamVR in the search bar
Add the SteamVR Player Prefab to your scene
Select the SteamVR folder from the Project tab
Select the arrow, open InteractionSystem, open Core, select Prefabs
Drag the Player into the Hierarchy tab

Add your Maya File to your scene
Select the Maya file in the Assets list
Select the Model tab in the Inspector
Change the Scale Factor to .3
Uncheck Import Cameras
Hit Apply


Drag your Maya file from the Assets list over to the Hierarchy tab.

Pause the animation until selected
Select your Maya Model in Assets

Switch to the Rig tab in the Inspector
     Change Animation Type to Legacy  (default was Generic)
     Hit Apply
Switch to the Animation tab
Rename Take 001 to a unique name
     Hit Apply

Select the Maya Model in the Hierarchy
     Uncheck Play Automatically in the Inspector

Add Interaction to the Model
Select the Maya Model in the Hierarchy
    Add Component->Physics->Collider 
     Choose the closest shape.
     You may need to Edit the shape using Edit Collider in the Inspector.

Use Add Component

     Search for inter
     Select Interactable Button Events
Hit the + under On Trigger Down () in the Inspector

Drag and drop Maya Model from the
Hierarchy onto None (obj) in the Inspector
Click the drop down menu reading No function and choose  Animation->CrossFade
Type Take 001 (use the new unique name) in the empty box below


You can now test your scene by selecting the Play arrow. Your animated object will start its animation when you grab it with a trigger.

Publish WebGL