Oh Noes! Scratch project cannot display.Flash player is disabled, missing, or less than version 10.2.
I found the equations (in Cartesian Coordinates) to draw an interesting image "lecteur à lunettes" in the blog of Guy Marion "Le Blog mathématique d'ABC".
Music "Vals marriage"
Thanks Paddle2See for helping me to draw a nice smooth line.
Scratch is a project of the Lifelong Kindergarten Group at the MIT Media Lab