Rays was research and development for the larger personal project "jamaphone".

I was trying to develop a particle system that could pack the particles by size, making them not collide and only be born where they could fit.
While I was working on that, curiosity grew in me and I wanted to see if the particles could interact with other dynamic objects like the fluid simulation in an efficient low cost manner. This was the result of my findings.

I used SideFX Houdini, Redshift