Högni and Amy's game project

Thought in deed

Posts Tagged ‘Artificial intelligence

Behave your trees

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I had already started using the good ol’ switch/case statement method to start implementing the AI for spacewars, when I bumped into Behave for Unity3D. This library implements Behavior tree logic in Unity with a nice visual editor. After a few minor niggles, finding workarounds for a couple of bugs and a lot of wrapping my head around how B-Trees really work, I love it.

The concept is so simple and intuitive, once you get past the initial (low) barrier you can be pushing out complex algorithms in no time. When you have your logic mapped out, all you have to do is implement the individual action and decorator code snippets. This fits so well into the Unity style scripting – where there are lots of short scripts – the workflow does just that.

Behaviour trees also integrate fairly well with FSMs, so you don’t have to instantly throw them out. You can have the tree actions change states or alter parameters if needed, maintaining interoperability.

There are other tools out there to create B-trees, but this one for Unity is very much sufficient.

Written by Högni Gylfason

20.07.10 at 19:16