Y'know those line art programs? I put one on Scratch. However, I made it so you can have a cycle of up to 3 steps instead of just 1. Enjoy! Tip 1: Changing the cycle length usually makes it look much cooler. Tip 2: Play around with the values. Values of 30-200 for steps are best. Tip 3: When the pattern is just starting to be drawn, have Turbo Mode off, then turn it on. It gives the best experience.
NOTES: If your pattern hits an edge, some interesting and/or strange behaviour may result. I still think it can look cool. Right now, the only way to make another pattern is to click the green flag. I am planning to add an import/export feature. And yes, the rainbow is for Pride Month.