Welcome to this advanced tutorial on how to rig a head in Spine 2D to achieve a 3D effect! While I personally don't use this rig often, it can be very beneficial under certain circumstances. Consider rigging this way if your character is important in the game and appears big and in more than once scene maybe it is the main character or tutorial guide
Pros | Cons |
Produces the best result | Takes 4 hours of work |
It can adapt for eyes by also weighting eyelids | Requires artistic skills to reconstruct the face |
| Uses multiple Transform Constraints |
| Much more Vertex Transforms, since the mesh should be bound to 4+ bones |
This is not a tutorial on how to rig the full head, rather just about the final layer that allows 3D rotation of the head. I assume you already rigged head features such as eyes mouth and ears.
And this tutorial does not include binding meshes and constraining the bones
The main difference of the rig is that it gives us 4 bones to bind our meshes and constraint the bones of the facial features. And importantly they are rotating in perspective.
Building rotational structure
Create a bone name it face3D.
Add another bone inside face3D at 0,0 local coordinates and name it rotor.
[optional] Change the icons to better differentiate when clicking on them.
Now add 4 bones as children to rotor and add them at the Noth, West, South, East along the imaginary circle.
Select newly created bones and disable inheritance of rotation and scale.
Time to align the structure on the face and set correct perspective by scaling face3D bone.
Rotate the rotor to make sure that one of the bones is aligned with the nose.
Go to animation mode and animate rotation of the rotor from left to right
Time to bind the meshes and constraint the bones of ears, eyes, mouth etc.
When you give value to transform constraints in animation mode a key will be created. Remember to copy the values to setup mode and delete the keys at the end.
Fixing issues
Now at the end of the rig when everything looks great you might notice that when rotating head bone head distorts. This is because we have disabled inheritance of the rotation and scale of the 4 rotational bones. To fix it we should:
Select all 4 bones and create one transform constraint selecting head bone as a target.
Click on Match to save the offset
Mark Relative in the options
Set rotation and scale value to 100%
And reset constraints order if anything looks off.
That's it! Thanks for reading if any questions let me know in the comments section.
Download project to play with it!