Sine & Cosine Trigonometric functions created the 3d looping spiral wave patterns. I added the swimmer for a little entertainment.
Basic Description:
1- add light layer: open Expression for position (alt-click position), click on arrow to open JavaScript Math, choose Math.sin and Math.cos.
2- assign x=Math.sin; y=Math.cos; z=time*
2- add adjustment layer: add Expression Control: Slider Control
3- duplicate Slider Control to create 3 controllers (x,y,z).
4- rename controllers: Frequency (x), Amplitude (y), Speed (z).
5- pick whip Math.sin to controller X, Math.cos to controller Y, and time* to controller Z.
6- [x,y,z=value]
7- animate position of light emitter.
8- add values for each controller