AI-based animation for interactive storytelling

In this paper, we describe a method for implementing AI-based animation of artificial actors in the context of interactive storytelling. We have developed a fully implemented prototype based on the Unreal™ game engine and carried experiments with a simple sitcom-like scenario. We discuss the central role of artificial actors in interactive storytelling and how real-time generation of their behaviour participates to the creation of a dynamic storyline. We follow previous work describing the behaviour of artificial actors through AI planning formalisms, and adapt it to the context of narrative representation. The set of all possible behaviours, accounting for various instantiations of a basic plot, can be represented through an AND/OR graph. A real-time variant of the AO* algorithm can be used to interleave planning and action, thus allowing characters to interact between themselves and with the user. Finally, we present several examples of short plots and situations generated by the system from the dynamic interaction of artificial actors.