🧵 ..., while also being very close to colliding with another circle arc if we were to increase the angle a tiny bit further.

🧵: ...aligning one copied edge with one original edge and only inserting non-colliding shapes.

The magic is in choosing which pair of edges to align: varying the criterion gives vastly different output patterns.

I don't add noise explicitly, I think it's an indirect effect of the anti-aliasing values from drawing the shapes passing through the shader.
The shader maps the RGB values to a value s, then computes the modulo by a fairly small number and thresholds that. So it's quite sensitive to small changes.

Thanks! The algorithm is this: I overlay several layers filled with rectangles (actually very wide dashed lines), each layer in a different color and with low opacity. Then I apply a shader that maps the final color to B/W.