.TOX file that shows how to create different "zones" in a virtual environment, track the camera's movement through them, and trigger events based on that zone tracking. Used in a series of tutorials by Blake Marques Carrington called "TD as Game Engine", which dive into a very large project (over 6000 operators), in which TouchDesigner is used to create a first-person game-like experience for installation and performance contexts.
A tutorial explaining the contents of this .TOX can be found here: "TD as Game Engine, Part 4: Zones"