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The Computer Games Journal

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25-07-2017

Behavior Trees for Modelling Artificial Intelligence in Games: A Tutorial

Authors: Ryan Marcotte, Howard J. Hamilton

Published in: The Computer Games Journal | Issue 3/2017

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Abstract

We provide a tutorial introduction to behavior trees, which are a useful way of structuring artificial intelligence in games. A behavior tree is a model of plan execution that is graphically represented as a tree. A node in a tree either encapsulates an action to be performed or acts as a control flow component that directs traversal over the tree. Behavior trees are appropriate for specifying the behavior of non-player characters and other entities because of their maintainability, scalability, reusability, and extensibility. We describe the main features of behavior trees, show an example of how to create a behavior tree, and briefly survey existing packages for editing behavior trees. We recommend that behavior trees be used when some game designers are not programmers, the conditions governing the behavior are complex, and the NPCs have aspects of behavior in common.

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Title: Behavior Trees for Modelling Artificial Intelligence in Games: A Tutorial
Authors: Ryan Marcotte
Howard J. Hamilton
Publication date: 25-07-2017
Publisher: Springer New York
Published in: The Computer Games Journal / Issue 3/2017
Electronic ISSN: 2052-773X
DOI: https://doi.org/10.1007/s40869-017-0040-9

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