Chapter 13. Facial Animation Setup
WITH EACH GENERATION of hardware comes more scope for graphical detail. Facial animation is fast becoming a major element of video games; characters can not only speak but also express emotions. It used to be that a simple joint acting as a jaw was enough. This allowed the character's mouth to open and close, but the illusion failed to bring the character to life; instead, it looked more like a puppet.
Two of the most popular methods today of real-time facial animation use either joints or blend shapes. Joint-based animation simply uses a series of joints placed around the face that, when moved, serve to animate the character's face. Blend shapes, or morph targets, use duplicates of the face as a reference. The main face then morphs into the vertex-modified reference shapes.
This chapter demonstrates how to set up your characters using joints and using blend shapes, so that you can make up your own mind about which one to use in a particular situation.
Your choice will depend heavily on the game engine, so consult with the lead programmer first before embarking on a particular method. In addition, discuss the matter with your manager before you start work. Find out exactly what the character will need to do. If all it will ever do is blink, then there is no need to spend time creating multiple face shapes.