Advanced character rig (1/???)

Have you ever started to work on something that you thought would be easy?

And then after a while, everything starts to look like a big ole rabbit hole, but you keep on pushing forward because there's no way it could possibly be that deep... I mean, they have to call it a rabbit hole for a reason, right? There's no way a cute little fluffy bunny could possibly dig something deeper than a few meters, right?

Wrong.

Half way down the walls give way with a thunderous crumbling noise and the entire thing opens up into an endless chasm that swallows you hole. Soon enough, random bits of knowledge that you thought you'd never have to learn begin whizzing by at an alarming rate, and yet you continue to fall. Down and down the rabbit hole goes, until after a while you begin to wonder: A) how the !@#$ could anything have dug a hole this deep, and B) what the hell did I just get myself into?

That pretty much describes the majority of my experiences over the past month and a half.

It all started with my base character mesh. It's nothing complicated by itself, though it does have a bunch of extra geometry around some very specific areas designed for "future use". Around that point I realized I wasn't entirely happy with the way a lot of the joints bent, so I set out to fix that too. Then I hooked up the joints to the corrective blend shapes so everything would automatically engage and disengage based on the joint rotations, thus creating a natural appearance even when the joints were pushed to their absolute limits.

Okay, great, that all seemed to work fine.

Time to build the rest of the character rig!

Oh hello rabbit hole.

As it turns out, there's a heck of a lot of black magic voodoo that goes into this stuff. Especially when you want a rig that's stable for +/- 180° of joint rotation without your corrective morphs totally wigging out and turning your model into some sort of cross between Gollum and an undead zombie from Diablo (thatsnotmyfetish.gif). Unfortunately not many people cover this sort of thing on the internet- so it's largely up to you to figure it out yourself if you want to get anywhere.

So, yeah.

Attached is a demo video of my custom IK/FK setup. This is part of the system that will eventually serve as the basis for all my future models going forward. There's quite a few different things going on in here- there's an inverse kinematics rig fused with a forward kinematics setup, allowing one to blend between the two in the event that either isn't up to the task of representing the pose you're after. All that stuff is evaluated on a separate character skeleton, at which point the individual joint rotations are copied over to the joint chain that's actually bound to the character mesh- then finally the corrective morphs are applied to the model, fixing any issues with volume conservation and ensuring that the skin moves and slides around in a reasonably realistic way. You can actually see the corrective morphs turning on and off in the window to the left as the rig moves around.

Anyways, I do apologize for the lack of updates recently, but I've literally been bashing my head against this wall for the past several weeks desperately trying to figure it out. Thankfully it all seems to be working out now, so I can't imagine it'll take that much longer to figure out the rest.