ToonFace: A System for Creating and Animating Interactive Cartoon Faces
Kristinn R. Th—risson · 1996
The majority of facial animation work has focused on realistic rendering, often with complex underlying models of muscles and sometimes of facial tissue. A system for facial animation is described that takes a simpler, more artistic aproach. A face animated in this system is an effective vehicle for emotional and communicative expression. The scheme emplyed divides the face into seven features, each with a specific number of control points. Control points are moved with one- and two-dimensional Omotors.O Three kinds of filled polygons can be used to define areas and lines in the face. The simplest kind is a static, non-animated polygon, the second kind is associated with a whole feature (and all its control points), the third kind is simply associated with a single control point. As the control points are moved, either in one or two dimensions, the shape and position of animated polygons is modified to conform to the change, and thus change the facial expression. To achieve this, two kinds of interpolations are used. A face in this system is semi-3-D: it is defined in a 2-D plane that can be turned in three dimensions to simulate head turning and nodding. The result is a flexible system that can generate a range of facial expressions. The system comes in two parts, one being an Editor for constructing faces, the other being an animation engine for animating a face in real-time.