Spirographs, or rather, cycloids, have always fascinated me.

When I was in highschool, I got out of a math project (which was to write a poem about math) by deriving the equations for a hypocycloid and using those equations to produce a Spirograph generator, which, sadly, is long-since lost. The generator was fairly complete, going as far as to include a simply macro language for the generation of successive cycloid images. I used the software to produce several images, only one of which remains, and only in print form (I'll try to scan it later), but it was quite neat in its day.

I'm interested in potentially re-visiting the generator, as I now can derive the equations quite quickly and the program would be fairly simple to re-do. I'm wondering what the community interest in such a generator might be, and if there are any requests. The original generator could handle only a small set of parameters, but I'm giving some thought to trying to get it to do more, including epicycloid drawing and perhaps even custom shapes using collision detection. If I did this, what would you guys like to see? The project would probably be done with WPF. How many of you use a Mac? If there is enough demand for it, I may do it as a browser-based Silverlight application, allowing it to run on Windows, Mac, or Linux.

What do you all think?

-ps Spirograph is a registered, but poorly enforced, trademark of Hasbro. The proper name for a spirograph is a cycloid. Since nobody knows what a cycloid is, however, I often use Spirograph instead. Sue me.

These are the idea behind guilloche designs (the "Security" patterns on money, etc).

Here's a program that takes the concept to the limits!

http://www.excourse.com/excentro/

Got the trial for the mac - it's a Wonderful Program!!  (So Yes, I use a mac as well as a PC)

If you can do things like that...  You'll have a hit on your hands!

well well, if i figure it out how it is done i will use it in a forthcoming demo