nuclear@0: uniform sampler2D framebuf, dither_tex;
nuclear@0: uniform int dither_levels, dither_size;
nuclear@0: 
nuclear@0: void main()
nuclear@0: {
nuclear@0: 	float levels = float(dither_levels);
nuclear@0: 
nuclear@0: 	vec4 pixel = texture2D(framebuf, gl_TexCoord[0].xy);
nuclear@0: 	float lum = dot(pixel.xyz, vec3(0.2126, 0.7152, 0.0722));
nuclear@0: 	float coord_shift = floor(lum * levels) / levels;
nuclear@0: 
nuclear@0: 	vec2 dsz2 = vec2(float(dither_size), float(dither_size));
nuclear@0: 
nuclear@0: 	vec2 coord = mod(gl_FragCoord.xy, dsz2) / float(dither_size);
nuclear@0: 	coord.y = coord.y / levels + coord_shift;
nuclear@0: 	float val = texture2D(dither_tex, coord).x;
nuclear@0: 
nuclear@0: 	const vec3 dark_col = vec3(0.043, 0.286, 0.337);
nuclear@0: 	const vec3 bright_col = vec3(0.965, 0.778, 0.555);
nuclear@0: 
nuclear@0: 	gl_FragColor = vec4(mix(dark_col, bright_col, val), 1.0);
nuclear@0: }