Java Trirograph
Last updated: Saturday, April 14, 2007.

After making my Spirograph, I started thinking... what would happen if there was *another* gear, spinning inside the inner gear? Well, it was just a quick change so I implemented it. The patterns made are quite bizarre. I still haven't gotten around to cleaning up the interface, so the first number is the number of teeth on the biggest gear, the second number is the number of teeth on the middle gear, and the third number is the number of teeth on the third gear. The fourth number is the pen's position on a scale of 0 to 1. I think there's a flaw in the math somewhere actually, but it looks neat anyways. If anybody actually makes a Trirograph and tries it out, let me know if it's correct. :)

Well, almost five years after writing the original Trirograph, Rob Saunders found a bug that was stopping the third gear from changing size, and was kind enough to send along the fixed version. So now I present the new, improved Trirograph!

The source.

See also:
Brett Allen (
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