Rolling Circle Illusion (OR is it? see below) Click Flag to start the Illusion with default parameters. You can change the values of those parameters at any time, using the 4 sliders provided (one in each corner). Click the stage to toggle Line drawing Off/On. Roll Direction change now combined with Speed slider. *** NOTE *** to properly observe the effect of increasing the Loops parameter you will need to significantly increase the Balls parameter! *** ILLUSION ? *** NO, it's not. There is a Rolling Disc. If a big circle has a half radius disc rolling around inside it (so it's always touching the big circle's edge), any point on the inner disc's edge, traverses a linear path back & forth across the big circle. The Balls are just a bunch of points on the inner disc's circumference! To prove there is NO illusion, there's a ** New Feature ** when Loops = 1, to make the actual Rolling Disc that really is there, visible! Just click on the little Grey Disc! NOTE: The 1st time it's clicked, Balls is set to 2, because I think this setting is the clearest way to dispel the myth that there is an illusion here. Furthermore the rolling disc, can only be toggled on/off, if Loops = 1. My favourite parameter combination is "The Propeller" -Any Radius, 100 (or 50) Balls, 5 Loops, Speed 6!
