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digitalREFLECT
12-22-2008, 08:49 PM
Hey guys,

I am trying to do a cartoony facial setup and I'm trying to integrate a few different shapes into the mouth controllers. I have controllers for the right and left sides of the mouth. Heres what I am trying to do:

I have my setup with wire controllers on the face that are limited in translation from -1 to 1 in X and Y axis. (Z is locked). I have a blendshape for the mouth corner up, and a blenshape for the smile for each side of the face. I want to activate these shapes with the wire controller like this: When the controller is at Y,1 and X,0 I want the lip up shape to be activated, but not any of the other shapes. When the controller is at Y,1 and X,-1 I want the smile shape to be activated but not the lip up shape. Basically I want to implement this concept to create a smile that can be widen as the controller is pulled up and to the left, and then introduce more shapes for the narrow and frown, ect. The overall effect would be a mouth controller that moves in a square, and the mouth corner basically follows it with out creating ugly compund shapes from multiple blendshapes. I hope that makes sense.

If anybody has any ideas on how to do this with expressions or nodes or anything else, let me know! Thanks!!

SeanC
12-22-2008, 09:33 PM
the best reference / training you can get for this is "Stop Staring", its a great book all about facial setups by Jason Osipa.


heres a shortened version: (assuming you are using maya)

you need to use set driven keys from the controller to the blendshape weight (window - animation editors - blendshape). pretty straightforward, you already described what values need to be connected. :buttrock:

Brighton
12-23-2008, 05:20 PM
Stop staring is an ok book. Its a lot of Fluff for a pretty simple concept. A lot of the book is about setting up good geo for facial deformation.

Anyway, The Driven Key is the simplest way to go. Your Controller will be the driver, each blendshape the driven. Since I believe you can only have one active driven object at a time, you'll have to setup each half of the face by itself. Its really just a matter of keying the blendshapes opposite of each other. As the right blendshape hits 1 the left blendshape hits 0. But my guess is that 0,0 on the controller will be neutral face pose, so you may want that to be the midpoint where you switch the active shape.

SeanC
12-23-2008, 06:18 PM
Stop staring is an ok book. Its a lot of Fluff for a pretty simple concept. A lot of the book is about setting up good geo for facial deformation.

IMO the book is more about the so called "fluff" than the process of setting it up. The actual process of setting up the controllers is a very small reason why Stop Staring is great.

Detailed descriptions and studies of how the face moves when expressing certain emotions. Pictures from multiple angles of each blend compared to the neutral face. Descriptions for how to drive bump maps with your facial controls. As well as proper modeling workflows for each part of the face. Not to mention the tips and advice he adds..

The book has some basic concepts, but the reference and info provided is well worth it! especially for someone new to facial animation.. Must have!

Sorry had to stick up for this one.

Brighton
12-23-2008, 07:52 PM
IMO the book is more about the so called "fluff" than the process of setting it up. The actual process of setting up the controllers is a very small reason why Stop Staring is great.

Detailed descriptions and studies of how the face moves when expressing certain emotions. Pictures from multiple angles of each blend compared to the neutral face. Descriptions for how to drive bump maps with your facial controls. As well as proper modeling workflows for each part of the face. Not to mention the tips and advice he adds..

The book has some basic concepts, but the reference and info provided is well worth it! especially for someone new to facial animation.. Must have!

Sorry had to stick up for this one.
I don't want to imply that the book is bad in anyway. It has a lot of different techniques that it covers.
What I don't like about it, is that it only explains 1 aspect of the rig at a time. All perfectly valid approaches, but there is very little use in regards to game rigs.

I think thats the common problem with these books. They get very elaborate, but they seldom ever look at how to rig for games. Which is at least half the industry.

If I were a beginner looking at becoming a TD, this book is great at lightly covering the different techniques. As far as the anatomical references, its pretty good in explaining that linear interpolation of Verts from different Keyposes or Blendshapes is incorrect. But I would rather have a classical animation face reference guide.

I am flipping through the second edition book right now, and there isnt anything that I would say is "stupid" or "worthless", but I've seen better. I wouldn't evaluate it to face rigging as The Animation Survival Kit is to animating.

SeanC
12-23-2008, 08:51 PM
I'll agree with everything you said, but for this instance (setting up a face through blends and controllers) Stop Staring is exactly what digitalReflect is going for.

They are all good points, and I completely agree about having a classical animation reference for everything. This is a must!..

Cheers :beer:

digitalREFLECT
12-25-2008, 08:30 PM
Cool, thanks for the responses! I have actually been using Stop Staring for a while now to setup my faces. It is a good book. I found the interface it creates to be a little annoying to use. I would rather have a moreintuitive setup that is on the face itself. I know the Stop Staring method offers that, but I cant get that particular script to work.. which brings me to another problem with that approach. Its a little over-complicated (blendshapes to open the mouth..?) and if you dont have all the shapes, or a newer version of Maya, its hard to get the scripts to work completley.

My goal in this new face rig was to emulate the animation mentor rig, which is great. Simple to use, yet flexible. I think I may have to abandon this though because I think I may be overcomplicating the issue. Using driven keys doesnt seem to work either because they create unexpected results, and each channel ( X and Y) key independantly of each other. So if I have the smile keyed to 1 while the controler is at Y1 and X, 0 The smile will still be at 1 if the slider is moved to Y1 and X1 because technically the slider is still at Y1. Thats how it seems to be working for me anyway. Like I said, I think I am making this too complicated for myself. I think I am just going to use expressions on one shape and be done with it. The deforms wont be as good, but oh well.. :shrug:

JasonOsipa
02-01-2009, 02:35 AM
Its a little over-complicated (blendshapes to open the mouth..?) and if you dont have all the shapes...

Hey there!

Hold your fingers on your jawline and open your mouth. They move in, not down - opening your mouth simply isn't a hinge motion easily or well represented at all by joints. This wouldn't be an issue if no other shapes were expected to be mixed in, but unfortunately that likelihood is extremely high, and so the net deformation of the face, if not properly affected by each component shape, can quickly lead to undesirable effects (the wrong parts of the cheeks move/don't move!). If you still "don't like it", which is a perfectly valid thing to feel - you could always just bind the jaw, rotate it, and dupe the head - there you have an as-easy-to-do-as-binding-it open mouth shape (well, there is that tough work of ctrl+d ;) )

On the second comment about not having all the shapes there - you could always just dupe the head as many times as needed and put in "blank" shapes to get the scripts to run. Blendshapes store that kind of info VERY efficiently. (No change = ALMOST no data to save)

On the third, regarding scripts working in Maya, I actually regretted very quickly having a plugin ship with the 1st edition. With that in mind, on the second edition,we made sure everything was done script-based. If there are problems with the scripts from the 2nd Edition still, please PM me, I'd love to be aware of, and correct them.

Thanks! -J.

digitalREFLECT
02-02-2009, 04:33 PM
Hey Jason,
Thanks for the response! I did learn a ton from your book, so I hope you didnt take offense to anything in my last post. All of the rigs I've used professionally use a joint for the mouth open so I just got used to that method. I can see your point about using blendshapes. I guess joints would be my personal preference in this case. I've ben able to finish the rig I was posting about for now, but I am going to try and start a new one and pay closer attenetion to the details you were desrcibing. I havent tried using any of the scripts lately, and I'm in Maya 2008 right now, si I cant be sure of which ones are working or not, but if I find any specific problems I will definitely let you know.

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