LEMAN: A System for Constructing and Animating Layered Elastic Characters

Publisher Summary This chapter describes LEMAN—a system for constructing and animating layered elastic characters. Layered construction techniques which model anatomical features have shown promise in creating character models that deform automatically around an articulated skeleton. But purely geometric models, although they can be very expressive, usually require too much user intervention to achieve realistic-looking results. A hybrid approach in which layered models are constructed using a combination of geometric, kinematic and physically based techniques is the most promising one. The ideal 3D character model should provide a good compromise between interactive speed and realism, and between animator control and physically realistic behavior. The exact details of such a model are no more important, however, than the types of interactive technique used to construct and animate it. High-performance 3D graphics work stations and variety of multidimensional input devices have begun to make highly interactive, direct manipulation environments practical. This chapter describes the LEMAN system, originally developed at the Computer Graphics Lab of the Swiss Federal Institute of Technology, which can be used to construct and animate 3D characters based on the elastic surface layer model in such an interactive, direct-manipulation environment.