Just another dithering shader with up to date dithering:
Features:
gizmo-crt-shader/glsl_shaders/dithering at main · gizmo98/gizmo-crt-shader · GitHub
2Bit per channel examples:
No dithering
Bayer 4x4
Blue noise
EGA palette: No dithering
Bayer 4x4
Blue Noise
I think 2nd picture is the best. Bayer 4x4
Yep. Something looks wrong if i zoom in blue noise screenshots. I need to align input and noise texture.
Ok. I have added bayer 4x4 to glsl-shaders. Blue noise needs some love to align noise pattern with input puxel pattern.
Just fixed it in a slang shader with texelFetch.
Source: gizmo-crt-shader/slang_shaders/dithering at main · gizmo98/gizmo-crt-shader · GitHub
2Bit per channel - no dithering
2Bit per channel - blue noise
2Bit per channel - blue noise - ega palette
4Bit per channel - blue noise
I added a monochrome parameter and a shader variant which uses different blue noise textures for every frame so the dithering pattern does not look static.
Monochrome can be used to play snes games on a monochrome LCD 
.
1Bit monochrome
2Bit monochrome
Blue noise dithering and bayer 4x4 are now part of libretro slang-shaders.
Dynamic shader can be also used to limit color banding on 16-18Bit output devices which only support RGB565, RGB555 or RGB666 i think.
