dbf-udg

annotate sdr/dither.p.glsl @ 3:403ec1be3a1a

foo
author John Tsiombikas <nuclear@member.fsf.org>
date Fri, 11 Jan 2013 22:52:56 +0200
parents c45c7a1f7d9d
children 5f99c4c7a9fe
rev   line source
nuclear@0 1 uniform sampler2D framebuf, dither_tex;
nuclear@0 2 uniform int dither_levels, dither_size;
nuclear@0 3
nuclear@0 4 void main()
nuclear@0 5 {
nuclear@0 6 float levels = float(dither_levels);
nuclear@0 7
nuclear@0 8 vec4 pixel = texture2D(framebuf, gl_TexCoord[0].xy);
nuclear@0 9 float lum = dot(pixel.xyz, vec3(0.2126, 0.7152, 0.0722));
nuclear@0 10 float coord_shift = floor(lum * levels) / levels;
nuclear@0 11
nuclear@0 12 vec2 dsz2 = vec2(float(dither_size), float(dither_size));
nuclear@0 13
nuclear@0 14 vec2 coord = mod(gl_FragCoord.xy, dsz2) / float(dither_size);
nuclear@0 15 coord.y = coord.y / levels + coord_shift;
nuclear@0 16 float val = texture2D(dither_tex, coord).x;
nuclear@0 17
nuclear@0 18 const vec3 dark_col = vec3(0.043, 0.286, 0.337);
nuclear@0 19 const vec3 bright_col = vec3(0.965, 0.778, 0.555);
nuclear@0 20
nuclear@0 21 gl_FragColor = vec4(mix(dark_col, bright_col, val), 1.0);
nuclear@0 22 }