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PaxtonGerrish
01-13-2004, 04:34 PM
Ok.. this is a maya issue im shocked hasnt been solved yet.
I dont ever recall encountering theproblem in 3d max, so surely theres atleast a work around in maya..

many people have pulled their hair out over the same thing, and id like for it to be solved once and for all..

Im referring to that ugly Ik pop that occurs when you fully extend a limb.
There is an option called joint damping, but alias says it hasnt worked since version 3..
I heard it may be a scale issue, but iv tested that theory and it doesnt seem to be true.

Does any one have any ideas, or better yet solutions?.
your help would be much appreciated.

Paxton

dwalden74
01-14-2004, 11:54 AM
Im referring to that ugly Ik pop that occurs when you fully extend a limb.

Tell me about it! :D Joint damping just doesnīt work. I sure wish theyīd either fix it or just remove it from the UI. The only solution Iīve heard of for this is scaling your leg joints to compensate the pop. In theory this should work, and is certainly faster than tweaking feet/hips for every step (which can be an insane task).

Another possibility is to put rotation limits on your leg joints, so they stop rotating just before the pop occurs. So far I havenīt really seen this as a big help though...

How does MAX avoid this problem?

cheers-
David

antweiler
01-18-2004, 10:59 AM
a good untechnical solution for this is to create your bones with more bend than your geometry. example: model a leg for your character and create it straight, but create the bones with a bend. when animating, the leg would "overbend" when the ik chain is straightened, meaning it is less likely to happen, because the animator has more tolerance.
yes, limiting joint rotations also helps, it helps to make the ik pop less dramatic and disturbing. joint damping is just crap, and trying to get results is a waste of time.
i hope i could explain what i mean...

antweiler

dwalden74
01-18-2004, 04:18 PM
I just retested joint limits on my characterīs legs, and it worked quite well this time. This walk cycle uses joint limits on the knees. (http://www.david-walden.com/mov_chaplinWalk.htm) I previously rendered this with no joint limits and the legs would "pop" a bit more dramatically on the contact poses (looked almost like the knees were bending in the opposite direction- in fact, this was happening). So I activated MIN joint limits on the knees at a value of 0. This is the value of the knee at the bind pose, and the legs were created with a very slight bend to them (1-4 degrees or so). The benefit here is that the legs never extend *totally* straight (which is what causes them to pop), yet they can still take advantage of the stretching in the rig. Cool. :)

-David

PaxtonGerrish
01-21-2004, 06:20 PM
woo hoo thanks guys!! a combo of joint limits and placing the knee bone basicly inside the knee cap did the trick. works great..

i just hope there arent any problems that arise when weighting :eek: ..

cheers
:beer:

kiaran
01-22-2004, 08:43 AM
.i just hope there arent any problems that arise when weighting

The actual world space of the joint only effects the initial smooth weighting. When you go in and paint them manually it doesn't really matter if your knee joints are outside of the geometry.

nottoshabi
01-22-2004, 09:36 PM
I have managed to get around that problem by making sure that the leg joints are straight before I aply the ik and it seemed to work for me I haven't had poping knees since then.


:bounce:

dwalden74
01-23-2004, 07:09 AM
I have managed to get around that problem by making sure that the leg joints are straight before I aply the ik

Thatīs strange. I had tested this earlier too, but saw no difference in the popping behavior. It pops everytime the leg is extended completely straight, regardless. For me the only solution was to make sure the leg could never straightened out.

nottoshabi
01-24-2004, 09:04 PM
Hmmmm :hmm: ..


What version r u using?

dwalden74
01-25-2004, 11:18 AM
5.01, but I donīt think that really matters.

nottoshabi
01-25-2004, 08:01 PM
Ok I will replecate what I did and get back to you on monday or so.

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