[Algorithms] banding

[Andras B. <ba...@in...>]

whooo, i've been playing around with my (semi real-time :) raytracer
and i've just realized how really bad banding is even in 24 bit true
color... (best seen on a plane lit by one positional point light)

since i don't have hardware capable of 12bits/channel, i guess i'll
have to go with dithering.. now, how can i dither true color images
efficiently (fast, yet nice)? should i add some random noise?? should
i randomly perturb the normal vector (so it's not perfetly flat)? how
can i do these operations fast (realtime)?

i've tried randomly inverting each color channel's last bit, thereby
randomly decrementing/incrementing the pixel's value, but it doesn't
look convincing (to be honest, i looks worse than the original)...

any ideas?


bandi

ps: bandi has nothing to do with banding :)