BT Lab
Classroom tool
The lab runs the opponents from Vagrancy, a physics sword-fighting game, and shows what each one's behavior tree did on each tick. Choose two opponents and watch them fight, or fight one yourself with the keys. The opponent's tree is drawn in full, with the selectors and sequences that ran this tick lit, the conditions that held or failed marked, and the move still running from an earlier tick shown as running.
A panel follows the running action down to the keys it pressed. A scripted move shows the line of its script that is playing. A pose, such as high guard, shows its controller: for the shoulder and for the elbow, how far the joint is from the pose, the turn it aims for, the turn it has, and the key that follows. A search shows each key combination it tried and its score, and the throw shows its steps. A timeline records the last three seconds of keys, marked where the running move changed. The match can be paused, stepped one tick at a time, or slowed to an eighth of its speed.
Using it in class
The class tour has a step for each idea: a tree made of tasks, the selector as a fallback list, the sequence as a plan, actions that keep running over many ticks, a script, a pose controller, a search, the throw as a plan inside one action, parallel trees, a repeating decorator, and a fight of your own. Each step loads two opponents that show the idea, runs the match until the move it is about starts, and ends with a question for discussion.
The lab runs in the browser as a page of the game's own site, and it does not write a save file: a match played in it is not recorded.