ABSTRACT
Behavior trees and state machines were originally separate techniques—each with their own positive and negative points. The intent behind behavior trees is to make a series of character behaviors, whereas the intent behind finite-state machines is to make a stable cycle of character actions. The artificial intelligence (AI) Graph system has a real-time debug system that connects to and communicates with the game’s run-time. Active nodes are highlighted on the decision graph tool as they are executed. During development, this makes finding any problems in the decision graph much easier. AI Graph maintains scalability, variation, and diversity in character AI design through the course of development because of its data-driven approach. The chapter explains the AI Graph structure, operation principle, and examples from FINAL FANTASY XV. AI Graph is a node-based graph system in which it is possible to make a hierarchical structure with a GUI-based node graph tool. The tool works both offline and while the game is running.
