Attaching bones

RogueWars

Is it possible to attach 2 bones from 2 separate spine animations.
For example, I have 2 spine animations; the first one is my player model and the second is a firearm.
I would like to attach the gun's handle bone to my model's hand.

Is that possible with the unity runtime?

Misaki

RogueWars Yes, you can achieve that by using the BoneFollower component. You can examine the example scene Spine Examples/Getting Started/4 Object Oriented Sample on how to set up a BoneFollower component. In this example scene, a BoneFollower component is used in the PARTICLES Gun GameObject to align the particles with the tip of Spineboy’s gun. The same can be done with a Spine GameObject.

RogueWars

Misaki
Perhaps I am misunderstanding the BoneFollower, however it seems to just attach a GameObject to a spine bone?
What I am trying to achieve is attach a specific bone from 1 spine animation to another specific bone of another spine animation.
How would I specify both bones in this case?

Misaki

RogueWars Oh, sorry that I missed that point! You can use the SkeletonUtility component for that purpose: http://esotericsoftware.com/spine-unity#SkeletonUtility

The following steps should allow you to achieve it:

Select your SkeletonAnimation component and in the Inspector unfold the Advanced section and click on Add Skeleton Utility.
Click on Spawn Hierarchy and choose Override all bones. (This affects even unrelated bones, but the unwanted hierarchy can be deleted later.)
Select the bone in the hierarchy that you want to follow the bone of another (target) skeleton , then add a BoneFollower component to it.
Set the target skeleton's SkeletonAnimation to the SkeletonRenderer property in the added BoneFollower component. Then, set the Bone Name property to the target bone.

Let me know if I am still misunderstanding what you want to do.

Harald

@RogueWars I think Misaki misunderstood your exact use case in that using the above steps, the root bone would follow another skeleton bone. From the example of the firearm in the first posting I assume that you want to place two hand bones of a character skeleton at two separate locations at the firearm to hold it with two hands. If that's the case, then you would still use the SkeletonUtility component and spawn a hierarchy of SkeletonUtilityBones, however you would want to spawn all SkeletonUtilityBone objects with mode Follow all bones instead of Override all bones, since you only want to override the two hand bone locations. Then you would set the SkeletonUtilityBone of the hand bone to mode Override to adjust the bone to the current GameObject location each frame. Then add a BoneFollower component to let the GameObject follow e.g. the gun skeleton's handle-L bone location.

RogueWars

@Misaki @Harald
I want the root bone on my firearm to follow the holder-primary bone of my character.

I followed the steps above but sadly it does not seem to work.

I did the Add Skeleton Utility on both character and firearm Skeleton Animations.

I added the BoneFollower Component to the root bone of my firearm:

*SPINE View being the character's Skeleton Animation

But sadly the weapon does not follow the hand, did I make a mistake here?

Misaki

RogueWars Unfortunately, it is not clear from that screenshot alone what is wrong. I have recorded a screen video of the setup process (this is based on what Harald explained, not along with the steps what I described in my previous reply), so I hope this will be helpful:

RogueWars

Misaki
I had forgotten to put the SkeletonUtilityBone to Override mode, thank you.

Misaki

RogueWars I’m glad to hear you've figured it out! Thank you for getting back to us 🙂