source: GTP/trunk/App/Demos/Illum/Ogre/Media/materials/programs/X3DCompositor.hlsl @ 916

uniform int column[15] = {0,2,3,5,7,0,2,4,5,7,0,2,4,5,7};


        

const int phaseR = 0, phaseG = 1, phaseB = 2;

struct VS_QUAD
{
        float4 Position : POSITION;
        float2 UV               : TEXCOORD0;
};


int eye_pixelpattern(float2 scrcoord, int renderPhase)
{
        float i = floor(frac(scrcoord.x / 5) * 5);      
        int cureye;
        if(renderPhase == phaseR){
                float r = floor(frac((0 + i*5) / 8) * 8); // (0 + i*5) modulo 8
                r = floor(frac((r + scrcoord.y)/8)*8);
                cureye = (int)r;
        }
        if(renderPhase == phaseG){
                float g = floor(frac((2 + i*5) / 8) * 8); // (2 + i*5) modulo 8
                g = g-1;
                g = floor(frac((g + scrcoord.y)/8)*8);
                cureye = (int)g;
        }
        if(renderPhase == phaseB){
                float b = floor(frac((3 + i*5) / 8) * 8); // (3 + i*5) modulo 8
                b = floor(frac((b + scrcoord.y)/8)*8);
                cureye = (int)b;
        }
        return cureye;
}

float4 X3DPS(float2 UV : TEXCOORD0,
                        uniform sampler2D tex3Sampler : register(s0),
                        uniform float width, //window width
                        uniform float height)//window height
                        : COLOR0 
{       
        const int SAMPLE_ROWS = 4;
        const int SAMPLE_COLS = 2;
        
        float2 WPOS = float2(UV.x * width, UV.y * height);
        
        int cureyeRed = eye_pixelpattern(WPOS, phaseR);
        int cureyeGreen = eye_pixelpattern(WPOS, phaseG);
        int cureyeBlue = eye_pixelpattern(WPOS, phaseB);
        
        float4 col = 0;
        float2 M = float2(0.5, 0.25);
        
        float colR = floor(fmod(cureyeRed , SAMPLE_COLS));
    float rowR = floor(fmod(floor(cureyeRed / SAMPLE_COLS) , SAMPLE_ROWS));

    float colG = floor(fmod(cureyeGreen , SAMPLE_COLS));
    float rowG = floor(fmod(floor(cureyeGreen / SAMPLE_COLS) , SAMPLE_ROWS));

    float colB = floor(fmod(cureyeBlue , SAMPLE_COLS));
    float rowB = floor(fmod(floor(cureyeBlue / SAMPLE_COLS) , SAMPLE_ROWS));
        
        col.r = tex2D(tex3Sampler, M * (UV + float2(colR, rowR))).r;
    col.g = tex2D(tex3Sampler, M * (UV + float2(colG, rowG))).g;
    col.b = tex2D(tex3Sampler, M * (UV + float2(colB, rowB))).b;
        
    return col;     
}