source: GTP/branches/IllumWPdeliver2008dec/IlluminationWP/demos/OgreGames/SpaceStation/Media/GTPPostProc/GTPPostProc.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;
}

float4 Black_PS(VS_OUT IN):COLOR
{
   return float4(0,0,0,1);
}

float4 Copy_PS(VS_OUT IN,
                uniform float width,
                uniform float height,
                uniform sampler2D Texture: register(s0)) : COLOR 
{
   IN.texCoord += float2(0.5/width, 0.5/height);
  // return 1;
   return tex2D(Texture, IN.texCoord);
}

float4 AlphaBlend_PS(VS_OUT IN,
                uniform float width,
                uniform float height,
                uniform float alpha,
                uniform sampler2D Texture: register(s0)) : COLOR 
{
   IN.texCoord += float2(0.5/width, 0.5/height);
        return float4(tex2D(Texture, IN.texCoord).rgb, alpha);
}

float4 Add_PS(VS_OUT IN,
                uniform float width,
                uniform float height,
                uniform sampler2D Texture1: register(s0),
                uniform sampler2D Texture2: register(s1)
                 ):COLOR
{       
   IN.texCoord += float2(0.5/width, 0.5/height);
   return tex2D(Texture1,IN.texCoord ) + tex2D(Texture2,IN.texCoord );
}

float4 Combine_PS(VS_OUT IN,
                uniform float width,
                uniform float height,
                uniform float weight1,
                uniform float weight2,
                uniform sampler2D Texture1: register(s0),
                uniform sampler2D Texture2: register(s1)
                 ):COLOR
{       
   IN.texCoord += float2(0.5/width, 0.5/height);
   return tex2D(Texture1,IN.texCoord ) * weight1 + tex2D(Texture2,IN.texCoord ) * weight2;
}

half4 Luminance_PS(VS_OUT IN,
                uniform half width,
                uniform half height,
                uniform sampler2D Texture: register(s0)
                ):COLOR
{       
   IN.texCoord += half2(0.5/width, 0.5/height);
   half4 sample = tex2D(Texture,IN.texCoord );
        
   // D65 white conversion and weighting
   half avg = sample.r * 0.21f + sample.g * 0.39f + sample.b * 0.4f;
   return half4(avg, 0, 0, 1);
}

float4 GlowCut_PS(VS_OUT IN,
                uniform float width,
                uniform float height,
                uniform float cutValue,
                uniform float timeBlur,
                uniform sampler2D Texture: register(s0)
                ,uniform sampler2D LastTexture: register(s1)
                 ):COLOR
{       
   IN.texCoord += float2(0.5/width, 0.5/height);
   float4 sample = 2.0 * tex2D(Texture,IN.texCoord );
   float luminance = dot(sample.rgb, float3(1.0, 4.5907, 0.0601));
   if (luminance < cutValue) sample = float4(0,0,0,0);
   float alpha = timeBlur;
   sample = sample * alpha + tex2D(LastTexture, IN.texCoord) * (1.0 - alpha);
        
   return sample;
}

float4 GlowBlurH_PS(VS_OUT IN,
                uniform float Stretch,
                uniform float width,
                uniform float height,
                uniform float timeBlur,
                uniform sampler2D Texture: register(s0)) : COLOR
{
   float2 tex0 = IN.texCoord + float2(0.5/width, 0.5/height);
   float4 texLookUp_h;
                        
        /*texLookUp_h =  tex2D(Texture, float2(tex0.x-(3.86979f*Stretch/width), tex0.y)) +
                                         tex2D(Texture, float2(tex0.x-(1.72291f*Stretch/width ), tex0.y)) +
                                         tex2D(Texture, tex0) +
                                         tex2D(Texture, float2(tex0.x+(1.72291f*Stretch/width), tex0.y)) +
                                         tex2D(Texture, float2(tex0.x+(3.86979f*Stretch/width), tex0.y));*/
        
   texLookUp_h = tex2D(Texture, float2(tex0.x-(2.0*Stretch/width), tex0.y))  +
                 tex2D(Texture, float2(tex0.x-(1.0*Stretch/width ), tex0.y)) +
                 tex2D(Texture, tex0)                                        +
                 tex2D(Texture, float2(tex0.x+(1.0*Stretch/width), tex0.y))  +
                 tex2D(Texture, float2(tex0.x+(2.0*Stretch/width), tex0.y));

   return float4(texLookUp_h.rgb / 5.0, timeBlur) ;
}

float4 GlowBlurV_PS(VS_OUT IN,
                uniform float Stretch,
                uniform float width,
                uniform float height,
                uniform float timeBlur,
                uniform sampler2D Texture: register(s0)) : COLOR
{
  float2 tex0 = IN.texCoord + float2(0.5/width, 0.5/height);
  float4 texLookUp_v;
                
           /*texLookUp_v =    tex2D(Texture, float2(tex0.x, tex0.y-(3.86979f*Stretch/height)))+
                                         tex2D(Texture, float2(tex0.x, tex0.y-(1.72291f*Stretch/height)))+
                                         tex2D(Texture, tex0)+
                                         tex2D(Texture, float2(tex0.x, tex0.y+(1.72291f*Stretch/height)))+
                                         tex2D(Texture, float2(tex0.x, tex0.y+(3.86979f*Stretch/height)));*/

   texLookUp_v = tex2D(Texture, float2(tex0.x, tex0.y-(2*Stretch/height))) +
                 tex2D(Texture, float2(tex0.x, tex0.y-(1*Stretch/height))) +
                 tex2D(Texture, tex0)                                      +
                 tex2D(Texture, float2(tex0.x, tex0.y+(1*Stretch/height))) +
                 tex2D(Texture, float2(tex0.x, tex0.y+(2*Stretch/height)));
        
   return float4(texLookUp_v.rgb / 5.0, timeBlur);
}

float4 ToneMap_PS(VS_OUT IN,
                uniform half width,
                uniform half height,
                uniform half Gain,
                uniform sampler2D Scene: register(s0),
                uniform sampler2D AvrLuminanceTexture: register(s1),
                uniform sampler2D LuminanceTexture: register(s2),
                uniform sampler2D GlobalLuminanceTexture: register(s3)
                 ):COLOR
{       
        IN.texCoord += half2(0.5/width, 0.5/height);
        
        float gLum = tex2D(GlobalLuminanceTexture, float2(0.5,0.5)).r;
        gLum = max(gLum, 0.31415);
        
        // Automatic key calculation
        //half Key = 1.03f - 2.0f / (2.0f + log10(tex2D(AvrLuminanceTexture, IN.texCoord).r + 1.0f));   
        //half Key = 1 / (tex2D(AvrLuminanceTexture, IN.texCoord).r / 1 + tex2D(AvrLuminanceTexture, IN.texCoord).r);
        //return 1 / Key;
        // Relative luminance
        //half RelLum =  Key* tex2D(LuminanceTexture, IN.texCoord).r / 
        //                                        tex2D(AvrLuminanceTexture, IN.texCoord).r;
        half Key = 1.03f - 2.0f / (2.0f + log10(gLum + 1.0f));  
        half RelLum =  Key* tex2D(LuminanceTexture, IN.texCoord).r / gLum;
        half Lum = RelLum / (1 + RelLum);
        // Color weghting
        half4 Color = tex2D(Scene, IN.texCoord) /  gLum * 0.4f;
        // Gamma correction
        
        //Color = pow(Color * half4(1.05f, 0.97f, 1.27f, 1.0f), Gain);
        return Color + 0.0000000000001 * Gain;
        //return gLum;
        return float4(tex2D(GlobalLuminanceTexture, IN.texCoord).r,
                                  tex2D(GlobalLuminanceTexture, IN.texCoord).r,
                                  tex2D(GlobalLuminanceTexture, IN.texCoord).r,
                                  1);
}