Define your own spiral as a function that takes the current radius and returns the current angle in radians

Your function is run for several evenly-distributed radii between 0 and 1. The number of sampled radii increases with time, which leads to interesting animations.

Inspired in part by "The Hypnotic World of Degenerate Spirals"

Functions are defined using a "Reverse Polish Notation" syntax. Here are the different operations it supports:

I use a similar expression format in other places: