Tutorial: Bichoís facial animation system

(january 2003)


    Hereís the full description of Bichoís facial system. A lot of people asked me about it and I always say that itís nothing complex. Youíll find that itís a very easy but powerful system. Itís based in two techniques: basic morphing and global deformersís morphing. The main idea for Bicho was to build a character with a enormous facial expression, with a lot of elasticity, but you can use this system for every character you want, specially cartoon characters.



Head pieces


   Bichoís face is compound by the head, the two eyes and two eyelids over the eyes, all of them separated objects, so the blinking of the character is done by rotating each eyelid.



Basic morphing


   The first step is making the basic Bichoís gestures with the standard morphing. There are only four morphing targets as you can see in the first picture: angry eyes, smile, open mouth and squash mouth. Some of this morph targets can be used in negative values so that you can create the opposite gesture: 

Positive Negative
surprise eyes angry eyes
smile sad mouth
squash mouth strech mouth

This means that we have a total amount of 7 basic gestures. As you can see they donít have a special appeal and they donít get the objective of elasticity that I was looking for. So this take us to the second step: the setup of a global deformer to enphasize the eyes gestures. If you see Bichoís movie you can check that all the power of Bichoís facial expression is in his eyes.



Global deformer's morphing


   Bicho have a global deformer (Max FFD or Maya Lattice) for all the objects in the upper side of the head (eyes, eyelids and head, a total of 5 objects). This deformer affects all of these objects. The purpose of this element is to affect the volume of this area.

To get it we are going to make morphing of this deformer. The next step is to make the morph targets. There are only four: angry, pity, squash and right eye enlarge/left eye smaller. 



You can also use the negative values of this targets to get the opposite effect, the same that we did with the basic morph targets. As you can see this gestures are also a bit horrible by themselves, but remember that they're only made to enphasize the seven basic gestures .





   So thatís all. The only thing you have to do now to create your facial animation is to mix the gestures provided by the two techniques. If you try this system youíll see that the only difficult is to decide what are the gestures that youíre going to need and, obviusly, the result that you want to obtain. We use to forget this last thing a lot of times. Try to keep in your mind what you want to see when you finish your work, and it will help you to avoid wrong steps in your character creation, for example, creating lots of complex gestures that you donít really need because you can get them mixing basic gestures. Check the animation books (I can recommend you ďCartoon animationĒ by Preston Blair), they will help you to know what are the main facial gestures used. 



Bicho facial animation system tutorial - january 2003