Pattern-based AI scripting using ScriptEase

Creating realistic artificially-intelligent characters is seen as one of the major challenges of the commercial games industry. Historically, character behavior has been specified using simple finite state machines and, more recently, by AI scripting languages. These languages are relatively "simple", in part because the language has to serve three user communities: game designers, game programmers, and consumers - each with different levels of programming experience. The scripting often becomes unwieldy, given that potentially hundreds (thousands) of characters need to be defined, the characters need non-trivial behaviors, and the characters have to interface with the plot constraints. In this paper, the ScriptEase model for AI scripting is presented. The model is pattern-template based, allowing designers to quickly build complex behaviors without doing explicit programming. This paper describes ScriptEase's behavior patterns and user interface. This is demonstrated by generating code for BioWare's Neverwinter Nights game. In addition to behaviors, the model is being extended to include encounter, dialog, and plot patterns.