Describes how an AnimationStream is initialized
On every frame, the values in the AnimationStream must be reinitialized. AnimationStreamSource describes which values should be used: the default values as stored in the Animator, or the result of previous inputs.
| DefaultValues | AnimationStream will be initialized with the default values from the Animator. |
| PreviousInputs | AnimationStream will be initialized with the values from the previous AnimationPlayableOutput connected to the same Animator. |