Game AI Pro 3

9

Overcoming Pitfalls in Behavior Tree Design

Anthony Francis

9.1    Introduction

9.2    What Makes Behavior Trees Work

9.3    Pitfalls in Behavior Tree Design

9.4    Conclusion

References

9.1  Introduction

Unless you have been living under a rock, or are new to the game industry, you have probably heard of behavior trees (Isla 2005, Champandard and Dunstan 2012). Behavior trees are an architecture for controlling NPCs based on a hierarchical graph of tasks, where each task is either an atomic, a simple behavior an agent can directly perform, or a composite, a behavior performed by a lower level behavior tree of arbitrary complexity. As they provide a cleaner decomposition of behavior than alternatives such as hierarchical finite-state machines—and ...