Trochor – Animated Virtual Harmonograph
June 23
The pattern traced out by Trochor is what you’d get if you took a pencil moving in ellipses, and used it to draw on a sheet of paper that’s also moving in ellipses. It’s a bit like a spirograph, but not constrained in quite the same ways. It’s more like a harmonograph; more on that later.
Have fun, play around with the settings, especially ‘ratio’; that’s probably the best way of figuring out what’s going on. ‘Eccentricity’, by the way, is a measure of how flattened an ellipse is – an ellipse with 0 eccentricity is a circle, one with 1 is a line.
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