It's nothing like the graphic that I posted yesterday but I'm quite proud of it. Making simulations in GeoGebra has become a bit of a hobby, like doing crossword puzzles (which I also do) or siduko (which I don't). The challenge here was to get the wave to rotate but I solved that by making the points have the same sinusoidal motion in two dimensions then made the amplitude of one cosθ and the other sinθ. Seems to work OK.

---