Custom Rigs, and Facial morphs for Next Gen Chars.

Robbiek1000

So lately I've been asking a lot questions about next gen. characters, and now I'm to the point where I need to take it a step further in hopes to learn everything I can about what it takes to make a great next gen character.

For as long as I can remember I've always used 3Ds Max's bipeds to do all my skinning and animating, mostly because of the ability to lock feet and hand into a certain positions and I've gotten pretty good results so far, but I feel its time to learn how to make custom rigs. My first question however is how many of the game we see being made today use custom rigs anyway. To be honest I don't really know for sure so that mights sound like a stupid question, sorry. I would love to hear that a lot of game engines can use Max's bipeds, but for some reason I don't think that's the answer I'm going to get. So if anyone know and good reference or tutorials on making really bad ass custom rigs please, please send me the link. Any advice and guidance would be appreciated, because I am always looking into further understanding the technology I am using.

Also I was curious about facial animations on next gen characters. I know how the normal map process works and everything, but one thing that been bugging me is how I should go about modeling the mouth. If I know I'm going to be opening and closing it for animation purposes should i model the mouth slightly open, closed, or does it matter. you never really see how a person goes about modeling and normal mapping the mouth and that something I've always been curious about. Oh, and the teeth and tongue how should I go about modeling low poly teeth and should I worry about modeling a tongue? Again, any reference or tutorials would be a huge help.

I appreciate all you time, and look forward to some helpful advise.

Robbiek1000

Mark Dygert

It's almost a studio by studio basis. It wouldn't be a bad idea to hit UDN and read up on characters, since quite a few places use the Unreal Engine. BiPed is kind of the easy way out, of course you can make a really nice custom rig but who has the time. BiPed just makes so many things easier. Of course that ease of use tends to dick you over some times. But because its easy a lot of people use it.

As far as facial animations go thats another bag of worms. For Gears Of War I think they used FaceFX, but it really depends on the engine that is used if you will be able to use morph targets/blend shapes, bones, or some custom set up.

Annosoft has a pretty nice set of tools.
Voice O Matic is a morph based lipsync tool that works as well as the morphs you make, but not every engine can do morphs.

Sorry I can't be more of a help, but the question really should be how XXX dev do rigging and facial animations.

The studio I work at uses BiPed and Morph Targets.

aesir

Actually, quite a few engines can and do use biped.

Unless you want to be a rigger, knowing how to make custom rigs is not really necessary.

animatr

unless you're using maya...which probably half the studios do.
our rig is rather simple. we animate mostly straight on the bones and just throw on IK when we need it using default tools. this is mostly to accomodate mocap. we do have a full custom rig, but it's rather complex and tends to slow most of us down.
about the face, we have a custom face rig. also, when modeling the face, since I am a technical artist at work, i get the joy of point weighing all the models. and models with the mouth slightly open are sooo much easier to weight. otherwise, it is a total bitch sorting through the verts trying to discern which are top and bottom. also, yes, you can/should model teeth and tongue. at the very least, teeth.

Eric Chadwick

We're not a game developer per se, more like middleware, but we support both Biped and Bones setups. We can use IK, scripted controllers, etc. on our bones, all of which gets stripped down automatically at export time into standard FK. Some realtime IK in the works for sticky feet, etc. But it's nice to be able to use the full toolset for animation production. Some toolsets though support only vanilla FK rigs, with fixed numbers of bones, etc. Not sure which studios still do this or not.

Paul Neale is a kick-ass 3ds Max rigger, great tutorials and tech on his site.
http://www.paulneale.com/

You might check out Granny, the guys over at Rad have done an awesome job with their rigging system.
http://www.radgametools.com/granny.html

Also projectmessiah has some good info.
http://www.projectmessiah.com/

Ben Cloward

Our engine supports both custom rigs and biped rig exporting, but personally, I really don't like the biped. Every time I try to animate with it I just end up really annoyed. I never have been able to get used to it's quirkiness. For several years I just made a new custom rig for each character, but that was a lot of work. In the last year or two I've written a MaxScript that automatically builds the custom rig that I like to use based on the positions of some helper points that you lay down to define where the joints should go. I highly recommend this route because building a custom rig for each character is a very labor intensive and repetitive process. The more you can automate it with MaxScript, the better. Once you've got your rigging scripted, any time you come up with a cool new rig idea, you can just add it to your script and then all the rigs you make from then on will have that feature. So after you've used the script in production for awhile it just keeps building on itself and getting better and better.

If you'd like to take a look at a script that works in a similar way, Mike Comet wrote a great one. I used his script as reference when I was learning how to create mine. You can download it from his site on this page:

http://www.comet-cartoons.com/maxscript.php


We generally model our characters with the mouth in a neutral pose and just slightly open. We also model a set of teeth, but they're pretty low detail and mostly rely on the texture. We did put a tongue in one of our most high detailed characters, but you mostly never notice it, so we haven't bothered on any of the rest of them.

For facial animation, our engine supports both bones and morph targets so we can use either one, or mix and match them depending on which works best for a specific situation. Up until now, we've been using mostly morph targets.

SkullboX

[ QUOTE ]
[...]mostly because of the ability to lock feet and hand into a certain positions and I've gotten pretty good results so far[...]

[/ QUOTE ]
I've never understood Biped's way of handling this. There are like 3 or 4 different types of keyframes for the feet and hands. On a custom rig locking down the hands or feet is simply done with IK, and the way it interpollates depends on the keytype (which is basically what the planted/sliding/orsomething keys do). In maya it's also pretty easy to make an incredibly solid IK/FK switch. So this feature isn't unique to biped at all, I personally think biped's incredibly bad at handling all this. Unfortunatly Max's custom rigging abilities - while far better than biped's - are nowhere near as good as those in maya, where everything just seems to work.

Biped of course does have its advantages, mainly the lack for any understanding of the rigging process (buidling a rig that can do the same as biped save transfering animations between different setups already is quite a bit of work) and the ease to incorporate it into a pipeline. Because of this however, rigging and anmiations are never quite catching up with the level of detail of the rest in games, since rigging is often (but by the looks of it increasingly less) handled by people who shouldn't.

As for exporter compatibility. Most games I've worked with mainly used the hierarchy of a skinned object and didn't distinguish between biped or bones, as long as it was a valid hierarchy. The only exceptions could export seperate .bip files for animations, but for exporting the static model+rig/binding there was no difference. Some characters require a skeletal setup that differs so much from the standard biped setup it would be a terrible waste to use all the bones in a biped (since the hierarchy of a biped can't be broken, unless the exporter has this as an option). Because of this being able to export custom rigs is almost always a must.

Good luck!

Kanno

Most engines I've ever dealt with are able to use both Biped and Bones. We've even used both in one rig before (Biped with extra bones hanging off). In the end all that the exporter is doing is pumping out rotation and position values to the bones in the engine so it theoretically should just be some extra work for the code dept. Character Studio is great in that you have it's "ease of use" but we've run into so many problems with it that it's insane. It's just really really buggy. I'd say (please read: hope) we'll be seeing A LOT LESS of it in next-gen stuff because quite frankly, if you have a decent in-studio rigger you could built a robust pipeline capable of swapping rigs, FK/IK blend and all those pretty planted/sliding keys without dealing with Character Studio's utter BS. TCB curves? Buttons that should be labled "crash"? Character Studio can pull off some great animation, but in the end most good animators that you're hiring come from features where Maya and XSI are setting the standards (and for good reason). Characetr Studio is sort of the Fisher Price kit for animation. That being said, even an easy-bake oven can make great cupcakes. Sorry for the rant.

As far as facial stuff. I have yet to see advanced(more than 4-6 bones) facial rigs but I'm sure someone will do it soon. For now it's mostly morph targets. Normal maps just have to be built intelligently enough that they don't get totally warped when polys get blended. Same as with bones driving movement (think shoulders on a muscley character). The main problem is that some engines have limits on how many morphs can be driving a mesh at once. Usually at least 3 though. Also, progressive morphs aren't always supported.

almighty_gir

just a small point on modeling lips (if you're intending mouth animations via skeleton rather than morph), either model the mouth slightly open, or, you can make the lips overlap slightly. either will achieve the same result. i've found having them overlap slightly gives me a better result when the mouth is closed.

i'm still learning how to build my own custom rigs... so i can't be much more help, sorry.