[rivo]

I programmed something like that back in 1999:

https://kuederle.com/university/fur/improvedtext.jpg

Each hair consisted of four segments. All segments were sorted, then drawn back to front. Each segment was drawn as an anti-aliased line (no hardware support for this back then, so I had to invent my own line renderer). So a hair could not be thicker than one pixel but that's a reasonable assumption at a certain distance. This made it reasonably fast given the hardware at the time.

I've been wanting to reimplement this using modern shaders, to see how fast it would be these days, but haven't gotten around to it yet.