Just playing around in TouchDesigner.

This is a particle system with motion tracking and without Kinect.

Lou Shi © 2023

Camera: captures the movement to create particles.
Mouse: xy to change particle external force, left click to reset.

Keys R, G, B allow you to add red, green, and blue colors to the particles respectively. tapping the key increases the amount of that color and tapping another will mix the colors. X key will reset the particles to black.
Keys 1, 2, 3 allow you to change the effect of the particles. 
1 is a smooth fade from 0 to 1000 particles, 
2 is a smooth fade to 1000 then an instant drop to 0, 
3 is an instant switch from 0 to 1000, then 1000 to 0,
4 Key will allow you to use default effect of 2000 particles always present,
5 Key will allow you to use default effect of 5000 particles always present. 

Thanks to Olivia Reyes for adding the keyboard controls.