I'm working on a color limiting auto-dither post-process shader for the Unity game engine. My original intention was to make it create NES Colored images; though thus far that has proven too expensive to do live (it could auto-perform postprocess for video but the algorithm as I wrote it was too inefficient for live for game.) I have completed it two color modes and three variation modes. Black and White (literally a two colored shader) and Spartan (red, blue, green and black); named after this piece which gave me the idea. The variation modes being noise/static, rotational and scanline.

Based on this still (or actually the 3D model that produces the still using a normal shader):



Spartan Scanline Mode

Showing only that preview so far because I think it's the most impressive of the modes I've completed (static and rotational modes are too chaotic for anything other than video art). The number n the middle is the current scanline width, which can be any value desired. Love some thoughts on it. Advice about how to get more colors into the dithering equations without killing my system or thoughts on how to make it more 'sprite like'; as that's really the intention make 3D art look like sprite art during use (and able to do all calculations live so that it could display a 3D game this way); similar to how a toon shader makes the shadows in a game look more cartoony or the shaders used in paper man made the 3D art almost look handdrawn. Also on a more complex object:



Edited by Bcadren - 09 June 2013 at 11:06pm

I don't think Unity LUT's can do dithering...can try though I'm not actually sure how to make the lookup textures it uses. And simply reducing the palette does posterize quite a bit; to do more I'd either have to edit default toon shader or write my own posterization effect. Pixel outlining is probably a good idea though I'm not exactly sure how to code that in I know the Toonshader pencil-like outline uses mesh interface code to extrude it off the mesh. Btw; JUST pairing it down to NES colors does this: (left = original; middle = 254x240 (NES resolution); right = NES Colors). Apologies for the anti-aliasing; it's the image host and I already deleted the original.