source: data/data_extern/programs/GLSL150/HalftoneFP.glsl

#version 150

in vec4 pos;
in vec2 oUv0;

uniform vec2 numTiles;
uniform vec2 iNumTiles;
uniform vec2 iNumTiles2;
uniform vec4 lum;
uniform sampler2D RT;
uniform sampler3D noise;

out vec4 fragColour;

void main()
{
        vec3 local;
        local.xy = mod(oUv0, iNumTiles);
        vec2 middle = oUv0 - local.xy;
        local.xy = local.xy * numTiles;
        middle +=  iNumTiles2;
        local.z = dot(texture(RT, middle), lum);
        vec4 c = vec4(texture(noise,local).r);
        fragColour = c;
}