source: GTP/branches/IllumWPdeliver2008dec/IlluminationWP/demos/OgreDemos/media/MORIA/GTPMoriaPostProc.hlsl @ 3255

struct VS_OUT
{
        float4 hPosition        : POSITION;
        float2 texCoord         : TEXCOORD0;    
};

VS_OUT Default_VS(float4 position : POSITION,   
                                float4 texCoord : TEXCOORD0)
{
   VS_OUT OUT;  
   OUT.hPosition = float4(sign(position.xy),0,1);       
   OUT.texCoord = (float2(OUT.hPosition.x, -OUT.hPosition.y) + 1.0) / 2.0;      
   return OUT;
}

#define NUM_DOF_TAPS 12

float4 DoF_PS(VS_OUT IN,
                uniform float width,
                uniform float height,
                //uniform float focalDist,
                uniform float focalRange,
                uniform float maxCoC,
                uniform sampler2D ImageTexture: register(s0),
                uniform sampler2D DepthTexture: register(s1)
                ) : COLOR 
{
   float2 filterTaps[NUM_DOF_TAPS];

   float dx = 1.0f / width;
   float dy = 1.0f / height;

   filterTaps[0]  = float2(-0.326212f * dx, -0.405805f * dy);
   filterTaps[1]  = float2(-0.840144f * dx, -0.07358f * dy);
   filterTaps[2]  = float2(-0.695914f * dx, 0.457137f * dy);
   filterTaps[3]  = float2(-0.203345f * dx, 0.620716f * dy);
   filterTaps[4]  = float2(0.96234f * dx, -0.194983f * dy);
   filterTaps[5]  = float2(0.473434f * dx, -0.480026f * dy);
   filterTaps[6]  = float2(0.519456f * dx, 0.767022f * dy);
   filterTaps[7]  = float2(0.185461f * dx, -0.893124f * dy);
   filterTaps[8]  = float2(0.507431f * dx, 0.064425f * dy);
   filterTaps[9]  = float2(0.89642f * dx, 0.412458f * dy);
   filterTaps[10] = float2(-0.32194f * dx, -0.932615f * dy);
   filterTaps[11] = float2(-0.791559f * dx, -0.597705f * dy);

   IN.texCoord += float2(0.5/width, 0.5/height);
    
   float focalDist  = tex2D(DepthTexture, float2(0.5,0.5)).x;
   float4 color = tex2D(ImageTexture, IN.texCoord);
   float centerDepth = color.a;//tex2D(DepthTexture, IN.texCoord).x;
        //return abs(centerDepth - focalDist);
   float blur = saturate(abs(centerDepth - focalDist) * focalRange);

   float sizeCoC = blur * maxCoC;

   float totalContribution = 1.0f;
   
   
   // Run through all taps
   for (int i = 0; i < NUM_DOF_TAPS; i++)
   {
                // Compute tap coordinates
                float2 tapCoord = IN.texCoord + filterTaps[i] * sizeCoC;

                // Fetch tap sample
                float4 tapColor = tex2D(ImageTexture, tapCoord);
                float tapDepth = tapColor.a;//tex2D(DepthTexture, tapCoord).x;
                
                float blur = saturate(abs(tapDepth - focalDist) * focalRange);

                // Compute tap contribution
                float tapContribution = (tapDepth > centerDepth) ? 1.0f : blur;

                // Accumulate color and contribution
                color += tapColor * tapContribution;
                totalContribution += tapContribution;
        }

        // Normalize to get proper luminance
        float4 finalColor = color / totalContribution;

        //return  tex2D(ImageTexture, IN.texCoord).r;
        return finalColor;
}

float4 sampleCenter_PS(VS_OUT IN,uniform sampler2D ImageTexture: register(s0), uniform float blending):COLOR
{
        float dx = 1.0 / 640.0;
        float dy = 1.0 / 480.0;
   float sample = 0;
   sample += tex2D(ImageTexture, float2(0.5, 0.5)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(dx, 0)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(dx, dy)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(0, dy)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(-dx, 0)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(-dx, -dy)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(0, -dy)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(-dx, dy)).a;
   sample += tex2D(ImageTexture, float2(0.5, 0.5) + float2(dx, -dy)).a;
   sample /= 9.0;
   
   return float4(sample, sample, sample, blending);   
}