[Figures 7-9] The character is smiling with an asymmetrical pose (left) setting up the move to an angry face. The face with the cheeks and nose (center) NOT being used. A face with the connectors tying the whole face together (right). The cheeks and nose are receiving the proper attention.

The most dramatic emotional shifts can be given higher intensity by shifting the asymmetry in reverse. For example, pretend the character is smiling out of the right side of his mouth and his right eyebrow is down. (See Figure 7.) Now he becomes angry and shifts to a frown on the left side of his mouth and raises the right eyebrow higher than the left. This reversal gives the character’s internal emotional shift an extra kick, helping it to read more clearly.

Facial Connectors
A telltale sign of inexperienced 3D facial animation is shown when the character’s mouth and eyebrows are moving, but the vast dead sea of face in between never moves. The face lacks a holistic connection within itself. Often, this disconnect between the eyes and the mouth will result in a confused message.

The trick is to think of animating the entire face as a whole, not just animating parts of the face. Because of the complex musculature of a face, it is nearly impossible to move the jaw without the muscles and skin all around it being affected, even all the way up to the eyes (see Figure 8). If you feel like a good lip-sync animator and a good eye- emotion animator, but you’re looking to put your work over the top, then you’re looking for connection. The primary connectors in a face are the cheeks, the nose and the ears (see Figure 9).

From a technical standpoint, you should try to build as much forethought into your facial morph targets as possible. Try to get the facial connector areas incorporated into your target building so that you’re maintaining connectivity for your face. Technically, from a morph target point of view, you’re going to want to make sure that you build push and pull into the nose, cheeks, and ears of a character. These face parts are highly driven by the underlying muscles used to make facial expressions. Here are a few tips to keep in mind when building your facial shapes:

• For the mouth corners up, make sure the ears are pulled up a bit.
• For the jaw open, make sure the ears are lowered a tiny bit.
• For the sneer, wrinkle up the nose.
• For the smile, make sure the cheeks rise up.
• For the jaw open, elongate the cheeks and slightly stretch down the base of the nose.
• Don’t forget about the neck muscles used to move the jaw and mouth corners.

Probably the single most useful technique to getting the face to seem connected and whole is to key-frame the entire face at once. The exception is the mechanical operation of lip- sync; that is usually treated as a separate issue and will be discussed at length shortly. But for emotional and expressive posing, you can often work on top of the underlying lip- sync. A person can say “Oh, yeah, I’m doing fine” and really mean it, or he can be snipping back sarcastically. In both instances, the lip- sync execution doesn’t differ much, but the entire face posing and expression is vastly different.

It’s in this realm of emotional expression that I am suggesting that you pose and animate the entire face as one unit. Treat faces like body poses. Faces have distinct and clear poses just as much as the body does. Ignoring this rule may result in a face that is haphazard in regard to timing and impact. You can certainly offset the key-frames in your finessing stage, but from early on you should use broad strokes in blocking in your character’s basic shifts in facial expression.