View Full Version : Understanding Blendshapes

12 December 2010, 10:40 PM
I have a character that I want to make blendshapes for the face and body.

The character is in one piece,rigged and textured.

My question is do I have to use the whole figure to make facial morphs and again the whole body to make morphs for knees, elbows etc.

Is there a way to make everything separate? Like just the head area or elbow area?

So that it only influences that specific area.

And if I use the full body to make facial and body morphs how do you prevent the morph from influencing the whole character? If you use a knee blendshape with a facial blendshape at the same time do they influence each other?

If I have to separate the head from the torso to make the blendshapes then how do you keep the influences working if you re combined your character so you donít have issues when animating the neck area (where you seperate the head from the torso?

And lose the blendshapes due to the typlogy changing?

12 December 2010, 09:15 AM
If you seperate the head, then you have to KEEP the head seperate. You could do a skinwrap/wrap deform onto your old un-seperated mesh if it is rigged.

If you dont seperate and build your blend shapes on the whole body instead then you wont have this issue. If you build a knee blend shape, then when you drive this shape on it will not affect other areas of the body unless your knee 'shape' also affects those other areas.

12 December 2010, 10:20 AM
Hello Matte thanks for such a quick response.

What is your work flow for a character ? Do you prefer to use wrap deformers? I read an article by Steven Stahlberg years ago who uses this method but I got messed up with his explanation on how he makes it work.

Is there a clear tutorial some where I can read about this?

Do you think using Maya's muscle system would be a better way to control body deformations rather than blendshapes?



12 December 2010, 05:51 PM
Personally I dont like using wraps unless I absolutely have to. That however is just personal preference.

I always work on characters with seperate heads and in some cases seperate body somponents. I then ensure the seams are skinned identically at the seams (I have scripts that I wrote which do this for me). The only issue with this method is getting visible seams where the normals on the edges arent smooth, but here at work we have shader tricks which work around this.

By breaking the character head off, I am able to skin and build morphs on that piece which I find much more manageable.

As for which system would be better for you it really depends on what you are trying to achieve. I have to say though that as we are a Max house here at Rockstar I haven't touched Maya for years so I'm not sure as to how good their muscle system is.

Good luck!

12 December 2010, 07:04 PM
Then you must be using CS and the Skin modifier?? I was the lead QA in Montreal for Character Studio for years, I then was QA on Maya until the big layoffs.

I did all the QA work for Maya Muscles along with helping do the online tutorials for advanced users on the Autodesk web site.

But like you said I have always seen the head being done seperate from the torso that is why I was wondering before I go down a path I can't retreat from. The implications of using the whole body when doing the morphs.

Thanks for your help!

12 December 2010, 04:40 PM
My pleasure!

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