Note: I've tried to make sure this website can be used with JS disabled, but some of the articles use MathJax to display math formulas. Those formulas will sadly be displayed as LaTeX code if your browser has JavaScript disabled.
While vising Tom Tits Experiment recently with the family, we saw an interesting experiment using a harmonograph. It was built with two big pendulums and a BIC pen, and it produced quite nice images, like this one:
I decided to try to replicate it virtually (not knowing anything about harmonographs or the curves they're designed to generate), and I came up with Penduolum:
The link to the project demo: https://valdes.cc/penduolum/
And the source code: https://github.com/jonvaldes/penduolum
Penduolum uses Notan as a general framework, and egui for the UI.
Thanks to my friend Nazarí González for the help and for building the Notan!