okay… this is an animal jaw, not a human one, so when the mouth opens, you see the teeth and tongue etc etc.
the tongue has its own bones, but the teeth do not.
when i started, with the auto-weight from bones, the teeth got stretched out everywhere, so i just grabbed them and painted them solid red – figuring the teeth move with the jawbone 100% because… well, they’re teeth. embedded in the jawbone.
but when i opened the jaw, the teeth would sink into the gums. okay, so then i figured, the teeth had to be the same weight gradient as the skin and gums (and tongue). so i erased (set to 0) all the jaw weights, and painted a gradient along the length, including skin, gums, teeth, and tongue, so they are all graded the same.
and yet, when i open the jaw, the teeth and tongue sink down into the jaw, and when i rotate it up the other way, the teeth and tongue fly out away from the jaw.
basically, the only time the teeth and tongue are in the right position are when the jaw is at 0 rotation.
THEN i figured… okay, the tongue vertices have tongue weights on them, and this normalize thing going on might make that mean that the jaw effect has actually less effect on the tongue verts, SO… i selected all the tongue vertices and set them to weight 0 for the jaw bone.
this had zero effect.
just… i don’t know how to fix this. i’m gonna guess it has something to do with other bones and weights??
okay, yes, sadly i was right. i went through the rig (face bones) and zeroed/removed the vertices from any groups not related to the jaw. AND also zeroed and removed vertex groups that were children of the jaw – such as the tongue, and the front lower lip controller.
Important Note To Self: if you’re not doing bones (ie: to save the facial details for later), make sure you ZERO THE WHOLE MESH to them.