Date of Award


Document Type

Thesis open access


Computer Science

First Advisor

Matthew A. Hibbs

Second Advisor

Xin A. Jiang


The ubiquity of human-like characters in video games presents the challenge of implementing human-like behaviors. To address the pathfinding and behavior selection problems faced in a real project, we came up with two improved methods based upon mainstream solutions. To make pathfinding agent take into account more incentives than only a destination, We designed a new pathfinding algorithm named Cost Radiation A* (CRA*), based on the A* heuristic search algorithm. CRA* incorporates the agent's preference for other objects, represented as cost radiators in our scheme. We also want to enable non-player characters (NPCs) to learn in real-time in response to a player's actions. We adopt the behavior tree framework, and design a new composite node for it, named learner node, which enables developers to design learning behaviors. The learner node achieves basic reinforcement learning but is also open to more sophisticated use.