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View Full Version : Convincing skin/muscle deformations on a high rez head


bertjenkins
07-29-2010, 09:44 PM
Hi,

I'm looking for advice on workflows for hi rez facial animation. I'm working on a chimpanzee project and i have sculpted the animal's head in mudbox. I'm going to rig and animate in maya and i want as much resolution in terms of facial deformation as is workable.I spent ages getting the topology right as i really want the skin folds/ creases and muscle groups to feel like they are deforming realistically. However before i start rigging i have a few questions as I've not done anything as hi rez/ photoreal as this before.

Has anyone got experience using vector displacement maps over a low res mesh? Is this worth pursuing? Are the deformations convincing? (ie the wrinkles etc) Are they tricky in mental ray?

Is it more reliable just to use a high res mesh with a wrap deformer?
Or is there an alternative workflow for the lo res/hi res proxy method?

Should i expect to be retopologizing, now that the high res mesh has new wrinkles, (bags under eyes etc) even though the base mesh has pretty good topology?

Also how do i go about creating the muscular stretches as seen on softimage's face robot, etc? Can i achieve this using blendshapes/ clusters alone (I'm familiar with Osipa, etc) ? Or are there any better methods to get deatail in the muscles, build FACS poses etc?

Thanks in advance, if you can answer any one of these i'd really appreciate it. Just want to avoid going all the way through rigging and skinning and realising (when it's too late) there's a much better way of going about it.

evengi
08-08-2010, 12:06 PM
Hi bertjenkins!

My approach to this, (myself working with facial mocap), was to build a face muscle setup and let this drive the face deformations.
I looked up face muscles and made a simplified muscle rig

When the muscles reach an extreme, and therefore should fold skin, I've did a setup where extreme poses blend in displacement maps, over my standard one.

So if the right eye is closed and calls upon wrinkles in the eye corner, my Y position of the eyelid triggers a slow blend in of the displacement, creating convincing results.

You could use a low poly rig, as long as the topology is optimized for animation.
Best luck to you!

Roger

bertjenkins
08-09-2010, 11:40 AM
Great that's just what i was looking for. Many thanks for taking the time to reply.

I think i'll go for something similar with a light model first, and try and get the deformations working in a rough way with displacement maps, then possibly resculpt/topologize and build the more detailed rig, depending on how effective it is.

I suppose a curve based rig is the best way to go if you want to match specific muscle lines?

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