The first place to get a sense of a character switching from happy to angry should be in the eyes. The rest of the face will come second, and the body will follow. From a motivational standpoint, a character must feel something before he can act something. So, you need to know what the character is feeling, then show that in animation. If a character is going to shift his feelings, you must show that inner shift in emotion in the eyes first. After that, you can move that emotional shift to the rest of the body.

Emotion
A person’s eyes cannot hide the inner realities of the heart. So while a person may put up a brave front, the eyes give away the keys to the soul. The lever to subtext in animation (subtext being the unsaid truth of the moment) is to show this truth in the eyes.

If your character’s eyes are missing the mark emotionally, then your character is lying. You can show a brave body, but if the eyes show fear, then fear is what is true, no matter what the bluster of the body is saying with its pose. If that’s what you want to portray, that’s great. The worst possible thing is to have your character’s eyes be off the mark by mistake. That’s akin to using words out of context. (Hey, don’t jump to contusions!) For this reason, it is imperative that you study and learn the values of expression in the eyes. There are several excellent resources for facial posing for emotional impact—one of the most popular being Gary Faigin’s book The Artist’s Complete Guide to Facial Expression. However, the best resource is studying real life. Watch people, watch good films (not junk films), and study great acting performances to instill new and varied meanings into your animation vocabulary. By expanding your vocabulary, you’ll be able to broaden your ability to speak to the viewer through the eyes of your character.

Blinks
Blinks are one of those odd areas in facial animation. There are good rules to follow, but they’re never “lock solid never shall we violate these rules under penalty of death and public shame” kinds of rules. They’re merely little things to keep in mind when you’re animating blinks. A few of these are…

• blink on head turns
• blink on eye shifts
• blink once every 30 frames or so
• standard blinks are two frames to close, one closed and five frames to open (on 24 fps)

As I said, these are generalities that may or may not work. The key to blinks, like everything else, is to think about them in context. A blink can be merely a mechanical process for moistening the eyes, in which case they’re unconscious and involuntary. This kind of blink shouldn’t draw attention to itself; it is merely there to keep the character alive. But a blink can also be intentional and motivated. Oftentimes, the inner emotions and thoughts of a character will drive a blink or two that isn’t strictly meeting a physiological eyeball-hydration need. A good example of this is a person who has just received shocking news. They may cast down their gaze in response and also blink quickly several times. This is a purely emotional, thought driven reaction. Blinks help humans make the jump from one thing to the next in the mind. Similar to a cut from shot to shot in a film, a blink is a cut from one thought or topic to another. It makes sense to blink when a character turns his head or shifts his eyes. He is “clearing the slate” in his mind. It’s realtime editing in your mind. If a character is struggling to focus, or is trying to process difficult information (“Your father has just died”), he will tend to blink more often in an attempt to try to clear away the confusion and find clarity in his mind. This gives voice to the rule that a person will double-blink when lying. The person knows he is lying, and he has to work harder in his mind to gather the lie. He’ll blink for clarity.

I usually create blinks last when animating a face, unless the blink is the primary action in the shot. By then your character’s body, mouth, eyes, and face should be communicating very clearly what needs to be said. You don’t want the audience to notice blinks, unless they’re supposed to for story reasons. Blinks in face animation are a lot like seasoning. You add them to round out the flavor of the acting, not as a foundation for it. But again, this is a generality. There will always be the occasion where the blink is the primary action of the shot or has a heightened level of significance.