What causes pinching when doing riggs?

[thorn3d]

It's caused by using geometry not suited for the rig you're using, or improper weighting/placement of bones.

thorn

[Just_David]

err..right. Okay say my geometry is sound. Say i take the shin bone and rotate it so theres a bend in the knee.. the shin then twists around the Y axis pinching.

Question. when posing my rigg should I be using control objects to SRT the bones or rotating the bones themselves. I new to this.

Then i do have the adam sale rigging vids. :cool:

[thorn3d]

err..right. Okay say my geometry is sound. Say i take the shin bone and rotate it so theres a bend in the knee.. the shin then twists around the Y axis pinching.


Post a screenshot.

thorn

[mr Bob]

you should not be rotating bones at all , you should just be translating the control objects...if you are moving the legs or rotating the foot controls to get foot roll.

B

[thorn3d]

Whether he's rotating a bone with the rotate tool, or rotating them via moving a control object - the resulting pinch (or lack of pinch) would be the same, no?

thorn

[mr Bob]

The point is he shouldnt be touching the bones and thats the answer to one of his question,as to pinching I would tend to lean towards large weighty character and joint placement , you might have to build in some shape animation into the joints. to get correct shape for the backs of the legs /elbows etc etc
Dave I suggest you look at the rigging videos you bought as they have examples of coping with that.

B

[ThE_JacO]

pictures of the rig and mesh, in both default and deformed states, would be helpful anyway.

I've seen pinching and bad deformations happening in so many cases and for so many different reasons, ranging from near unnoticable stray weights to complete and utter user idiocy, that it's not even funny.

there's many ways to create solid joint area deformers that are more efficient and versatile then brute forcing it with a shape (which will only work for one plane of rotation and could not even look good all the way through a wide arc).

[Just_David]

The point is he shouldnt be touching the bones and thats the answer to one of his question,as to pinching I would tend to lean towards large weighty character and joint placement , you might have to build in some shape animation into the joints. to get correct shape for the backs of the legs /elbows etc etc
Dave I suggest you look at the rigging videos you bought as they have examples of coping with that.

B

bob is correct. in my noobness i was rotating the bones and not the control objects and the result was that the bone was twisting to a new axis and pinching the mesh. Now that i look at the topoglogy it isnt the greatest either but i am getting proper deformation now when moving the control objects and i locally re-assign stray points to the proper bones.

Think i need to re-install the Adam Sale rigging vids and complete them.

Also where can i get tutorials or information on building edgeloops and proper modeling of characters of all types ie real, and cartooney. I think learning to layout the topologly would be a real help when it comes to enveloping.

[Just_David]

Sorry back again. I made a mistake and ended in losing my envelope. Anyways I started again and heres the initial problem I was having. Moving the control object you see the upper thigh or lower ass area badly pinch and deform.

Is this because I need to re-assign my points in that area for a better deform or is it something else?

Thx guys.

http://www.davidboyda.plus.com/images/Xsi_wip/rigerror1.gif

[mattmos]

A lot of that looks like the fault of the envelope - too many points assigned 100% to the thigh bone. Try weighting more to the hip bone and then smooth it out a bit so you have some graduation...

Also be very careful when weighting that you don't get points which aren't 100% enveloped. ie if you test moving the entire character they don't get left behind.

[Just_David]

will do .. thanks.

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