[vert.glsl]

#version 130

attribute vec3 in_Vertex;
attribute vec4 in_Color;
varying vec4 pass_Color;

uniform mat4 proj_matrix;
uniform mat4 view_matrix;
uniform mat4 model_matrix;

void main()
{
    gl_Position = proj_matrix * view_matrix * model_matrix
                * vec4(in_Vertex, 1.0);
    pass_Color = in_Color;
}

[frag.glsl]

#version 130

#if defined GL_ES
precision highp float;
#endif

varying vec4 pass_Color;

mat4 bayer = mat4( 0.0, 12.0,  3.0, 15.0,
                   8.0,  4.0, 11.0,  7.0,
                   2.0, 14.0,  1.0, 13.0,
                  10.0,  6.0,  9.0,  5.0);

mat4 cluster = mat4(12.0,  5.0,  6.0, 13.0,
                     4.0,  0.0,  1.0,  7.0,
                    11.0,  3.0,  2.0,  8.0,
                    15.0, 10.0,  9.0, 14.0);

float rand(vec2 p)
{
    return fract(sin(dot(p, vec2(12.9898, 78.2333))) * 123.4567);
}

void main()
{
    vec4 col = pass_Color;
#if defined GL_ES
    int dx = int(mod(gl_FragCoord.x, 4.0));
    int dy = int(mod(gl_FragCoord.y, 4.0));
    float t;
    if (dx == 0)
    {
        if (dy == 0) t = cluster[0][0]; else if (dy == 1) t = cluster[0][1]; else if (dy == 2) t = cluster[0][2]; else t = cluster[0][3];
    }
    else if (dx == 1)
    {
        if (dy == 0) t = cluster[1][0]; else if (dy == 1) t = cluster[1][1]; else if (dy == 2) t = cluster[1][2]; else t = cluster[1][3];
    }
    else if (dx == 2)
    {
        if (dy == 0) t = cluster[2][0]; else if (dy == 1) t = cluster[2][1]; else if (dy == 2) t = cluster[2][2]; else t = cluster[2][3];
    }
    else
    {
        if (dy == 0) t = cluster[3][0]; else if (dy == 1) t = cluster[3][1]; else if (dy == 2) t = cluster[3][2]; else t = cluster[3][3];
    }
#else
    float t = cluster[int(mod(gl_FragCoord.x, 4.0))]
                     [int(mod(gl_FragCoord.y, 4.0))];
#endif
    t += rand(gl_FragCoord.xy) - 0.5;
    t = (t + 0.5) / 17.0;
    col.x += fract(t - col.x) - t;
    col.y += fract(t - col.y) - t;
    col.z += fract(t - col.z) - t;
    gl_FragColor = col;
}

[vert.hlsl]

void main(float4 in_Vertex : POSITION,
          float4 in_Color : COLOR,
          uniform float4x4 proj_matrix,
          uniform float4x4 view_matrix,
          uniform float4x4 model_matrix,
          out float4 out_Color : COLOR,
          out float4 out_Position : POSITION)
{
    out_Position = mul(proj_matrix, mul(view_matrix, mul(model_matrix, in_Vertex)));
    out_Color = in_Color;
}

[frag.hlsl]

float4x4 bayer = float4x4( 0.0, 12.0,  3.0, 15.0,
                           8.0,  4.0, 11.0,  7.0,
                           2.0, 14.0,  1.0, 13.0,
                          10.0,  6.0,  9.0,  5.0);

#if 1
float4x4 cluster = float4x4(12.0,  5.0,  6.0, 13.0,
                             4.0,  0.0,  1.0,  7.0,
                            11.0,  3.0,  2.0,  8.0,
                            15.0, 10.0,  9.0, 14.0);
#endif

void main(float4 in_Color : COLOR,
          float4 in_FragCoord : WPOS,
          out float4 out_FragColor : COLOR)
{
    float4 col = in_Color;
#if 1
    int x = (int)in_FragCoord.x;
    int y = (int)in_FragCoord.y;

    // FIXME: we cannot address this matrix directly on the PS3
    float t = bayer[int(frac(x * 0.25) * 4.0)]
                   [int(frac(y * 0.25) * 4.0)];

    t = (t + 0.5) / 17.0;
    col.x += frac(t - col.x) - t;
    col.y += frac(t - col.y) - t;
    col.z += frac(t - col.z) - t;
#endif
    out_FragColor = col;
}