[Figure 10] A single expression changes to another single expression.

If the character is happy, key the whole face to be happy. Then, if the character shifts to sad set the whole face to be sad. (See Figure 10.) If you’re doing lip-sync on top of this shift, treat the lip-sync as a distinct technique. Animate the lip-sync first; then go in behind it and modify the face to fit the emotion.

A person’s facial shift will tend to be a moment in time. There may be offsetting, especially between the eyes and the lower face, but the viewer should get the strong impression that the shift in facial expression is a very distinct and identifiable moment. The various shapes that make up an emotion will change with similar timing.

When animating the face, don’t try to do too much at once. Lip-sync needs to have flow from one sound to the next, with relatively few “holds.” Eyebrows and overall expressions should be singular— tending to be held until there is a solid emotional and cognitive reason to change. There’s a lot of power in skillfully changing from one clear emotion to another in a shot.

The 12 Principles Applied to Faces
One of the temptations in animation is to insert the “12 principles” of animation as defined in the watershed tome, Disney’s The Illusion of Life. These 12 principles have become a foundation for understanding animation. However, with the passage of time, they have taken on a sacred aura. As a result, many beginning animators feel they absolutely must insert as many aspects of the “Magic 12” as they can into each and every shot. However, merely adding overlap for overlap’s sake is misguided.

It is accurate to say that all aspects of the “Magic12” have their proper place in facial animation. You do want to keep the face fluid, alive, and organic, so adding offsets and follow-through on the occasional emotion is needed. However, if you apply overlap and offset too much, the face becomes rubbery and loses its meaning. The face, more than any other part of the character, is a billboard of intent. Everything that the face does must be motivated by something. Any extraneous motion in the face will generate confusion. To do more merely for the sake of “the principle of it” is moving things without understanding why. And with facial animation, WHY is king. So as with all animation, know what you’re going to apply and why; then go ahead and apply it.

To learn more about posing and staging, character animation, walks, tools of the trade and other topics of interest to animators, check out Inspired 3D Character Animation by Kyle Clark; series edited by Kyle Clark and Michael Ford: Premier Press, 2002. 268 pages with illustrations. ISBN 1-931841-48-9 ($59.99) Read more about all four titles in the Inspired series and check back to VFXWorld frequently to read new excerpts.

Keith Lango is the computer graphics supervisor of the feature film at Big Idea Productions Inc. in Chicago, makers of the top-selling children’s video property Veggietales and 3-2-1 Penguins! Keith got his start in CG in the early ‘90s and has held positions as an illustrator, a senior animator, an animation supervisor, an assistant director, a CG supervisor and a writer. Keith has also co-authored and co-illustrated a children’s book as well as personally developed several award-winning short animated films. He lives happily with Kim (his wife of 14 years) and his three children: Candice, Laura and John Mark.

Author and series editor Kyle Clark (left) and series editor Mike Ford (right).

Series editor Kyle Clark is a lead animator at Microsoft’s Digital Anvil Studios and co-founder of Animation Foundation. He majored in film, video and computer animation at USC and has since worked on a number of feature, commercial and game projects. He has also taught at various schools, including San Francisco Academy of Art College, San Francisco State University, UCLA School of Design and Texas A&M University.

Series editor and author Michael Ford is a senior technical animator at Sony Pictures Imageworks and co-founder of Animation Foundation. A graduate of UCLA’s School of Design, he has since worked on numerous feature and commercial projects at ILM, Centropolis FX and Digital Magic. He has lectured at the UCLA School of Design, USC, DeAnza College and San Francisco Academy of Art College.