I investigated a gradient-descent-based concept adjacent to this back in like 2023 [0] inspired by the original 3DGS paper, I was pretty happy with the results I got with back-to-front alpha-blending and polar-coordinate gaussians for variable-curvature brush strokes. One of these days I should add another example gif to the repo besides just the Mona Lisa one that's currently there, but that's the only one I've got at the moment unfortunately.

[0] https://github.com/mkaic/painterbot

As someone with an arts degree (not in painting though, but still) it feels really really weird to see how that animation builds up the image. It feels less random than the old "simulated annealing with vector shapes" techniques, ending up somewhere that feels both similar and extremely far removed from how a human would do it at the same.

It's like… the way a trained human would paint feels kind of like how MSB radix sort makes an array look more ordered, going from crude to refined. The way your algorithm builds up an i|age feels like I'm looking at a radix sort that alternates between a stable MSB and LSB radix sort, which is weird as heck. It's fascinating, really.

Neat, watching it paint as an animation is pretty fun.