Recreating Animator.CrossFade State

Unity Engine
1

I’m having difficulties using the Animator API to precisely recreate a particular crossfaded state between two animations.
Specifically, I want to use CrossFade (or CrossFadeInFixedTime) to immediately set the animator to a state partially blended into the second state.

I’m aware that I can use the fixedTime parameter in Animator.PlayInFixedTime to set the animation to a particular time.

animator.Play("State1", 0);
// an unknown number of animator.Update calls, over the duration of someTime

// Attempting to recreate the exact same animation state
animator.PlayInFixedTime("State1", 0, someTime); // This appears to recreate the same state as if I iteratively called Update

However, I’m not having luck doing the same with CrossFade / CrossFadeInFixedTime.

animator.Play("State1", 0, 0);
animator.CrossFadeInFixedTime("State2", crossFadeDuration, 0);
// an unknown number of animator.Update calls, over the duration of someTime

// Attempting to recreate the exact same animation state
animator.Play("State1", 0, 0);
animator.CrossFadeInFixedTime("State2", crossFadeDuration, 0, someTime); // This does not recreate the same state as if I iteratively called Update.
// The crossfade would now begin crossfading for the full duration; I instead want the animator to be someTime into the crossfade

I’ve tried several combinations of using Animator.Update(deltaTime) to skip the animator into the desired partially-crossfaded state:

animator.Play("State1", 0, 0);
animator.CrossFadeInFixedTime("State2", crossFadeDuration, 0, 0);
animator.Update(someTime);

However, this doesn’t seem to do what I want it to, either; the animator appears to skip the crossfade entirely.

Am I misunderstanding how to use the Play/CrossFade/Update calls? It seems strange that I can’t use some combination of them to recreate a particular crossblended state.

2

It seems that this relies on some internal functionality of animator.Update.

These two blocks of code aren’t functionally identical, as I would have expected:

for (int i = 0; i < 10; ++i)
{
animator.Update(deltaTime);
}

and

animator.Update(10 * deltaTime);

I’ve found a tentative solution that involves manipulating the speed of the animator:

// Assumes animator.speed == 1
animator.Play("State1", 0, 0);
animator.CrossFadeInFixedTime("State2", crossFadeDuration, 0, 0);
animator.Update(0);
animator.speed = someTime;
animator.Update(1);
animator.speed = 1;

It’s not pretty, but so far it seems to accomplish what I’m looking for, and sets the animator into a state that is partially crossfaded between the two states.

Does anyone know why animator.Update(10 * deltaTime) doesn’t produce the same behavior as 10 calls to animator.Update(deltaTime)?

3

I’m trying to do exactly that right now. There seems to be a normalizedTransitionTime parameter in CrossFade and CrossFadeInFixedTime now but I’m not getting the results I’m expecting with that either.

I was wondering if the animationTime of both anims had to be the time at the begining of the transition or at the transitionTime we are trying to recreate.

4

So I’ve been trying animator.Update(transitionTimeToRestore) and that method above of manipulating animator.update + animator.speed, and it’s still not resuming the animations and transition state properly.

I’m trying to switch an entity rendered using DrawMeshInstancedIndirect and animated using a special shader with a standard GameObject+Animator character at runtime when physics interactions are required. It works flawlessly, except while in transition. I can’t seem to restore the proper animation and transition offset/timing.

There may also be some confusion in the terms used in the doc (from what I read on the forum)…
I’m quite lost.