BlendShapes & Clusters

[mwoliver]

HELP! I spent forever creating these clusters and weighting them just right for my characters eyelids. Then I created blendshapes for facial animation (which I know now should have been done first). Because of this every blendshape effects the eyelid clusters (opening the eyes more and more with each blendshape slider used). I have tried moving around the deformation order. I was told the order should be: (from the top down) Polysmooth node, Skin cluster, Eyelid Clusters, BlendShapes...

Is there anyway I can fix this without redoing the eyelid clusters? If that will even fix this problem...HELP!

[joojaa]

Select object in question and in the satus line theres a symbol with a arrow pointing at a box (Inputs of the selected object), click on it and selact all inputs. Now middlemouse drag the blend shape to desired place in deformation order!

[mwoliver]

Thanks for your reply, but I have already tried adjusting deformation order by dragging around the inputs. Blend shapes as I understand it should be first in the stack(last in the list) - they are still effecting the Eyelid clusters.

[joojaa]

I myself would put the clusters firts before the blendshape, and blendshape before any bone binding. I would then make sure the blendshapes do in no way modify the points in the eyelid clusters!

[mwoliver]

I have the order from top to bottom:
PolySmoothFace
SkinCluster
EyelidCluster
BlendShapes

I was very careful not to select any of the CV's included in the Eyelid cluster when modeling my blendShapes I still am baffled...

Could the bound skin be causing this problem? If the skinCluster includes weighting info for the CV's of the eyelid, the same one's controlled by the eyelid cluster and the eyelidCluster was created before the skin was bound... then the blendshapes when moving the CV's, even if they are not the cv's of the eyelid would also move adjoining cv's that are skinWeighted the same as them as dictated by the skinCluster? If so, what would be the easiest way to fix this?

I know I created everything in the wrong order...I am just looking for the least painless way to fix my stupidity.

--Thanks!

[ame]

Unfortunately form the sounds of it, what you have is far more complicated a fix than mere deformation order. It sounds like the blendshapes were created with a pose coming in from the eyelid joints, likely one that was slightly wider than the base shape itself. Add that slightly wider shape to itself 2,3 or 4 times, and you've got really-WIDE-eyes, to be sure.

I'll level with you straight-up; there is no fast way to fix this, but there are a few different things to try.:

1) If they are less than an hour's work, rebuild the blendshapes, being sure that when you duplicate your head to work create the shapes, IT IS IN THE BIND POSE (really, super, bongo important; it is in fact, why you have the problem you do right now)

2) Create a counter-eye-wide-shape to layer into all your blendshapes, add it into the blendshape node, leave it's slider set to one, then duplicate the head in each OTHER bshape pose (again, in the bind pose, or it'll just get worse) and then recreate the blendshape relationship with your "new" versions.

Basically, to sum up, the problem isn't the eyelid clusters, it's the blendshapes. One way or the other you're going to do some heafty surgery on them.

Good luck. -J.

[mwoliver]

Thank you very much - I think you got it.

I am a fool. the bind pose is with the eyes closed. I set a driven key for the clusters and left the default of 0 with the eyes half open (not the bind pose!) and then duplicated the head in this state to create every blendshape! That is exactly the problem...

What if I just remove the skin weighting from the eyelids? or wouldn't that matter... I have quite a few blendshapes, what if I translated them back to 0,0,0 (on top of the base shape) relocked them to the clusters, moved them into bind pose, then unlocked them and translated them back out? Would either of these work, or just cause more problems???

[ame]

follow me around the block on this one, it's weird:

create another blendshape that is EXACTLY the "wrong" eye pose you first had (half open), and nothing more. Name this thing "FIX" for the sake of this talkthrough.

Now, "go to bind pose" on the base head and ADD the new "FIX" shape to the blendshape node (you may want to use the options box for deform->blend shape->add and "specify" the bshape node if it gives you grief about adding another shape)

Now, set FIX to -1 (exactly the opposite effect as what it's been doing in all your shapes; it'll probably look REALLY weird, that's ok)

LEAVE that slider at -1. Let me repeat. For the rest of this, LEAVE FIX at -1.

Now, one by one, take each of the other bshape sliders, set it to 1, duplicate the head (copying the mix of whatever shape and -FIX), and then set the slider back to zero, moving on to the next shape, rinse, repeat. Once you've done all the shapes, you'll have a new set of target shapes that are now "fixed". You then delete the old blendshape node/relationship and create a new one using your new shapes. This should not break anything to do with your clusters, etc.

what you're doing is this: creating an "unbroken" shape (EXACTLY the good-twin to the evil-twin that caused this problem in the first place ) and ADDING that into all your broken shapes, thereby removing the problem. You then "bake" the resultant shape by duping the head (in it's bind pose, this time!).

Then you have a new batch of shapes to assign as blendshapes, this time, without the broken influence.

It's complicated, but the problem itself is complicated. I've written some tools to do this (well, most of it) automatically, but as it was done at work, I can't "release" it. I'm sure I'll recreate it at home some day and publish it on my site. Until then, hope the explanation will do!

Take care -J.

[mwoliver]

You are brilliant! Thank you very much!

I guess it is pretty simple logic. isolate the problem and subtract it out of the equation...

Thanks again - Matt

[ame]

No prob, you're very welcome. Tell you what: buy my book, and we'll call it even!