Improv: A system for scripting interactive actors in virtual worlds

Improv is a system for the creation of real-time behavior-based animated actors. There have been several recent efforts to build network distributed autonomous agents. But in general these efforts do not focus on the author's view. To create rich interactive worlds inhabited by believable animated actors, authors need the proper tools. Improv provides tools to create actors that respond to users and to each other in real-time, with personalities and moods consistent with the author's goals and intentions. Improv consists of two subsystems. The first subsystem is an Animation Engine that uses procedural techniques to enable authors to create layered, continuous, non-repetitive motions and smooth transitions between them. The second subsystem is a Behavior Engine that enables authors to create sophisticated rules governing how actors communicate, change, and make decisions. The combined system provides an integrated set of tools for authoring the `minds' and `bodies' of interactive actors. The system uses an English-style scripting language so that creative experts who are not primarily programmers can create powerful interactive applications.