Deformation Problems

[Anonymous]

Hello all. I'm rigging a cat for a future game and need some help. I'm an animator by trade, not a rigger, and this is only the second rig I've ever made. I'm having issues with mesh deformation and was hoping I could get some tips. Below is the skeleton I have, as well as some obvious deformation issues.

How do I fix pinching problems like this? I've tried to place the joints as close to the center of the mesh as I could, while still maintaining the anatomy. The only IK setup I have so far is for the legs. I would also like to know what's the best way I should go about skinning the back - should I just keep the joint chain, or include some sort of IK? I want him to be able to arch his back, crouch down, etc. Would really appreciate any help I can get on this!

[Anonymous]

I am also new and facing same problem, I think I will reduce/remove skining on such odd deformated polygons. 

[Anonymous]

It can be also 'paint skin weight tool' you are looking for to set the weight. 

[J450NP13]

Yep...it's paint weights.

[Anonymous]

Is it okay to use the paint weights to redistribute weight WHILE the joint is moved into the problem position? For instance, if I lift the leg, is it okay for me to paint weights on the verts while it's not in its bind position?

[J450NP13]

Paint the weight before you move any joints in the areas that you want that joint to affect.  If you turn the paint weight tool on you'll see that that area is probably black and not white.  

[Anonymous]

I did do that originally, but still had issues with how it deformed. I also tried using the weight hammer tool but that only helps minimally.

[J450NP13]

Post an image showing the paint weight tool on.

[Anonymous]

Here's the weight for the left hip:

And the left knee:

Here it is deformed:

[J450NP13]

Looks like you need to bring the knee weight down some.  The knee shouldn't affect the hip like that.

[Anonymous · Accepted solution]

In this position (problematic position), you need to paint

[Anonymous]

That's what I ended up doing, along with using the weight hammer, smooth tool, and occasionally tweaking individual vertices. Seemed to work out for me. Thank you!