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Face Rigging vs Using Morph Targets for Animating Face Expressions

polycounter lvl 7
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Swayam_9shah polycounter lvl 7
Hi, I would like to know a bit about Face Rigging vs using Morphs. We are a small studio but we want to add the features of Facial expressions movement. We focus on getting atleast 10-12 expressions on the face. So would it be worth to setup Rigging or can we get away with Morphs using Zbrush? MoCap is still under discussion, but if we use MoCap then Rigging is the way to go as far as I am aware.
Would be glad to hear some good workflows being used. Thanks

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  • monster
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    monster polycounter
    Morphs are less expensive for the CPU and GPU since there are less bones to transform. Also, if your characters will have very different facial proportions morphs will be easier to setup.

    Bones give you more freedom during animation since you aren’t limited to the few targets.

    You don’t have to pick one either. Maybe the main characters use all bones and the background characters just have a couple of morphs to blink and open their mouth. 
  • RN
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    RN sublime tool
    You need to get your terminology right. The way you're asking "rigging vs morphs" makes it sound like they're opposite things, but they're not.

    Rigging is the process of setting up a mesh to be animated, usually providing a convenient interface (like visual controls) for the animator to use when animating that mesh.
    Whether your rig is based on morph targets (aka blendshapes or shape-keys) or on a skeleton (aka joints or skinning) or both (like @TeriyakiStyle said, a hybrid), that's up to the designer of the rig.

    The animator shouldn't care about the technology being used, they care about being able to articulate and pose the mesh to do what they want, to tell a story.

    Jason Osipa (from the "Stop Staring" book) and Brian Tindall (from hippydrome) use only morphs for facial expressions. In fact Brian's method uses morphs for everything on the face, like using additive and subtractive movements to have independent jaw-opening and lip-sealing, as well as curving eyebrows and eyelids.

    Other people like to use mostly joints:
    http://polycount.com/discussion/comment/2616727/#Comment_2616727
  • Mark Dygert
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    FACS (facial action coding system), all the way, 100% best quality you'll ever do, works best with mocap and hand key'ed animation.

    BUT it really depends on what type of characters you're going to have and what kind of quality bar you're looking to hit. You obviously don't want to use a nuke to kill a flly so using a FACS workflow on a mobile RTS game isn't going to get you very far.

    IF the characters are made with a character randomizer/creator/customizer then you're animations will have to be fairly generic, in order to work with all of the different kinds of faces. The animations will probably be driven more by joints and less by morphs because the faces are different shapes. You have to give something up in order to be able to customize. Usually you'll end up using morphs in for the customization so they're still part of your workflow, just not for animation.

    IF you are animating specific characters that don't have shifting facial structures, leverage both joints, blends and normal maps to do the best animation you can possibly do. https://snapperstech.com/

    Even if you are locked into using only joints for the game (boo, burn your engineers at the stake), you can still use morphing meshes to animate inside of Maya or Max. Morphs can be easier to rig up to a control board, you dial in large face shapes instead of trying to cook up a way to drive dozens of joints into those same shapes. You then use point on poly constraints to tell the skinned joints to follow specific places on the morph mesh. The end result is a pretty quick rig that mostly animates like a morphed animation.
  • Swayam_9shah
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    Swayam_9shah polycounter lvl 7
    Hey Monster, Thanks for the Reply. One thought was to like @TeriyakiStyle mentioned, using a hybrid. So here is what I am thinking. 

    I can setup rig for the face in max, setup the base expression pose, get that to zbrush and bring back blendshape to Max, and setup control board for getting morphs and rigs to work together. I am not sure if this is the right way to do it and if it works well. 

    @RN sorry about that. Will be more careful next time. I was looking into Jason and Brian for their techniques and still researching how best I can use that.

    @Mark Dygert I have read abut FACS but i dont htink its something we have the capability to use right now with the amount of resources we have. :) 

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