From Performance Theory to Character Animation Tools

The artistic performance literature has much to say about expressive human movement. This chapter argues that powerful, expressive animation tools can be derived from the classic lessons and best practices in this field. A supporting software system for creating expressive character animation is presented that takes advantage of these lessons. To this end, an analysis of the literature was conducted and a set of key aspects of expressive movement were synthesized. To validate the approach, a subset of these aspects is represented computationally as movement properties, or properties for short. These properties provide a set of handles and language for expressing movement. They can be used to write character sketches, which are executable descriptions of a particular character’s movement style. They can also be used to edit and refine an animation. A semantics is provided that describes how the software framework allows these varied properties to be combined in specifying an animation. Examples of character sketches and edits are shown on movements of a standing character.