Compress/Stretch a bone in Unity using Spine's IK Mix?

Jjamesr2k · 8 мая 2020

I apologize that I come in here without basic knowledge of Unity (I'm a Spine animator) but I'm hoping to confirm whether Unity has a means to recognize the stretch/compress features of an IK-constrained bone to a target in Spine.

Programmers for the project I'm on have already made the constrained bone follow a target for ranged targeting needs with projectile weapons - but after placing a whip attack that I have working perfectly in Spine (using a combo of FK for the animation, and IK for the length and angle manipulation) - It doesn't seem to want to preserve the stretch/compress for the IK resulting in an attack that isn't the proper length in Unity.

I appreciate any confirmation - even confirmation on whether what I'm asking isn't possible without substantial programming work, or if there's a place better suited to look for an answer. Knowing whether something is or isn't available will help narrow down what should be suggested to the programmers.

Thank you!

Jjamesr2k · 8 мая 2020

Harald · 8 мая 2020

jamesr2k написал
It doesn't seem to want to preserve the stretch/compress for the IK resulting in an attack that isn't the proper length in Unity.

The spine-unity runtime shall respect all constraints of your skeleton that you set up in Spine. When you move e.g. an IK target in Spine and everything looks correct, you should see the same result when moving the same IK target bone programmatically in Unity via the spine-unity runtime.

Are you getting different results here?
How are you moving the IK target bone in your Unity project?
Coudl you share some screenshots or some code that demonstrate what your expected and actual outcome are?

In general, there should be no difference between behaviour in Spine and spine-unity.

Jjamesr2k · 8 мая 2020

Sorry, I don't have access to any work I can send. I'll have to talk with the programmer but the target bone is moved programmatically in Unity. In Spine, the only thing I do is make sure the constraints are set up and the Mix is properly animated as well as do the documents for setting up the rig for other animators.

Thanks for confirming that it should be functioning Harald. That will be a good first step to helping the programmer know where to search.

Harald · 11 мая 2020

Thanks for getting back to us. If you should find out that something is indeed behaving differently than in Spine in an isolated minimal use case, feel free to contact us again, we will be happy to fix any bugs.