My spirograph pictures were always lumpy and funny looking, and I wasted a lot of paper. Here's a way to make fun spirograph-type pictures with NO wasted paper. I downloaded this applet, directions & the math geek stuff from another web site (with permission) With the right settings (which I have provided), it looks a little like a dream catcher. Feel free to play here as long as you'd like! To save your artwork, hit the "print screen" button, then open any graphics program, start a new document, and hit control+v to paste. Crop off what you don't want.

Created by Anu Garg.

Here is how you can use the controls in this Spirograph applet:

The first three scroll bars in the control panel let you change R, r and O respectively.
You can use the next three scroll bars to change the color of the drawing. These scroll bars change the red, green and blue values of the color (in the range 0-255) respectively.
The last scroll bar lets you choose the number of iterations for the Spirograph. Move it to beginning and then slowly increase it to see how many iterations it takes to complete the spirograph.
You can use the Random button to select random values for the radii and color. The number of iterations is not changed by the Random button.

Math geek stuff:
A Spirograph is a curve formed by rolling a circle inside or outside of another circle. The pen is placed at any point on the rolling circle. If the radius of fixed circle is R, the radius of moving circle is r, and the offset of the pen point in the moving circle is O, then the equation of the resulting curve is defined by:
x = (R+r)*cos(t) - (r+O)*cos(((R+r)/r)*t)
y = (R+r)*sin(t) - (r+O)*sin(((R+r)/r)*t)

Date: 12.19.13.4.18 13 Etznab 11 Uo Cinco De Mayo 2006

All material on this page and all pages is (c) by me, Gevera Bert Piedmont, except where noted. All rights reserved. Contact me for permission to republish. I rarely say no.