SO Based Behavior Tree

Minimal ScriptableObject-based Behavior Tree for Unity. Per-agent deep cloning, clean lifecycle, optional queue sample.

Features

• Nodes are ScriptableObjects (reusable assets)
• Deep clone per agent (no shared mutable runtime state)
• Composites: Sequence, Selector, DeadlineSequence, Parallel
• Simple lifecycle: OnStart / OnUpdate / OnStop / Abort
• Queue System Sample (domain kept out of core)

Installation (UPM)

Package Manager > Add package from git URL:

Latest release:

https://github.com/mthnblgn/SO_Based_BehaviorTree.git?path=Packages/com.mthn.behaviortree#v0.1.4

Development version:

https://github.com/mthnblgn/SO_Based_BehaviorTree.git?path=Packages/com.mthn.behaviortree

Sample: select the package > Samples > Queue System Sample > Import

Quick Usage

1. Create > Behavior Tree > Behavior Tree (asset)
2. Assign a Sequence / Selector as root
3. Create Action / Composite node assets and drag them as children
4. Add BehaviorTreeRunner to your agent GameObject and assign the tree
5. Press Play

Example Node

[CreateAssetMenu(menuName="Behavior Tree/Action/Log")]
public class LogNode : ActionNode {
    public string message;
    protected override NodeState OnUpdate(GameObject agent) {
        Debug.Log(message);
        return NodeState.SUCCESS;
    }
}

DeadlineSequence

Acts like a Sequence but if the time budget expires it returns FAILURE immediately and resets its child index.

Sample (Queue System)

Demonstrates spot reservation, queue progression, and leaving behavior. Core package stays domain‑agnostic.

License

MIT

Contributing

Issues / PRs welcome. Please keep things lightweight and focused.

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Kept intentionally concise. See commit history for deeper details.

Note: package.json "unity": "2022.3" denotes the minimum supported LTS baseline; tested also on 6000.x.