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Doctor49152
02-15-2008, 06:07 PM
I followed Protons great tutorial on building a reverse foot rig. It's perfect for what I'm trying to do for a character. I love all of these tutorials, they are great! A HUGE thanks if you read this.

But now for a Noob boning question:

When I move the heel the IK chain follows like its supposed to, but I can move the whole thing too far away and the 4 bones for the foot separate from the leg bones stretching the whole thing out of proportions. How do I keep the whole rig fixed so the leg stays together and in shape?

Thanks.

SplineGod
02-15-2008, 07:17 PM
Thats the downside of that particular setup (as well as some other things I dont like). Its not one that I see commonly used. I tend to keep the ankle/feet goals as part of the rest of the leg hierarchy. I make the ankle the end effector (end of the IK chain).
In either case its possible to pull the character away but in the 2nd case at least the mesh doesnt distort. Just make sure as you pose that you dont pull things too far away.

IKBoost allows a rig to stay bound so that it cant be pulled away from a fixed bone.
Heres an example of a basic rig setup that I sometimes use:
http://www.3dtrainingonline.com/examples/char_rig_demo.zip
Heres an example of a base IKboost rig:
http://www.3dtrainingonline.com/examples/ikb_rig_demo.mov

WilliamVaughan
02-15-2008, 11:21 PM
But now for a Noob boning question:

When I move the heel the IK chain follows like its supposed to, but I can move the whole thing too far away and the 4 bones for the foot separate from the leg bones stretching the whole thing out of proportions. How do I keep the whole rig fixed so the leg stays together and in shape?

Thanks.


That's one of the cool things i like about the setup...it allows for a bit of stretch to occur. The trick is to keep the foot bones within reach of the ankle. If you want stretch....move them farther away from the ankle.

Remember...as the animator you set the key poses the way you want them to be. if you see stretching occurring then move the bones closer...

We've used this foot rig for years in production with great success. There are several ways to setup a reverse foot rig and I have found this to be the easiest to setup...IMHO.

I'd try several ways and pick what works best for you. Jonny Gorden has a great setup that is completely different then mine that works great...so does Todd Grimes.

Good luck and keep us posted with your findings.