Click the green flag. Use turbo Mode. Press <space> to reset (usually after you change a variable.) Press <s> to show or hide the variables. Press <f> to freeze or unfreeze. Press <m> to switch between basic and advanced control mode. Press <c> to toggle colour and white. For best results, use a simple ratio between <pend1_freqX> and <pend2_freqX>, such as 100:50, 100:60, 90:60, or 90:80. Have fun experimenting
Equations from Wikipedia: https://en.wikipedia.org/wiki/Harmonograph A harmonograph is a device used before oscilloscopes to view the patters made by musical tones. It used swinging or rotating pendulums, attached to a pen, which marked a piece of paper. The drawing was varied by changing the frequency of the pendulum swings, in proportion to one another, as well as the amplitude of the two pendulums, and their phase in relation to one another. The best patterns were formed with simple ratios of frequencies.
