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arXiv · 2209.01020

EvolvingBehavior: Towards Co-Creative Evolution of Behavior Trees for Game NPCs

Nathan Partlan·Luis Soto·Jim Howe·Sarthak Shrivastava·Magy Seif El-Nasr·Stacy Marsella
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Abstract

To assist game developers in crafting game NPCs, we present EvolvingBehavior, a novel tool for genetic programming to evolve behavior trees in Unreal Engine 4. In an initial evaluation, we compare evolved behavior to hand-crafted trees designed by our researchers, and to randomly-grown trees, in a 3D survival game. We find that EvolvingBehavior is capable of producing behavior approaching the designer's goals in this context. Finally, we discuss implications and future avenues of exploration for co-creative game AI design tools, as well as challenges and difficulties in behavior tree evolution.

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Nathan Partlan, Luis Soto, Jim Howe, Sarthak Shrivastava, Magy Seif El-Nasr, Stacy Marsella. 2022-09-01. EvolvingBehavior: Towards Co-Creative Evolution of Behavior Trees for Game NPCs. https://arxiv.org/abs/2209.01020

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