This processing sketch generates the 3D surface of the most saturated RGB colours in the HCL colour space. It uses Neil Panchal's port of chroma.js, which adds a handy 'saturate' feature that attemps to find the most saturated RGB colour for a given hue and luminance. Unfortunately, I think this feature also introduces some numerical error, resulting in the weird scalloped edges on the 3D surface. I'm pretty sure these scallops shouldn't be there, and they don't seem to appear on the 2D slices. They also don't interfere with understanding the colour space, so I haven't spent much time trying to fix them.