source: GTP/trunk/App/Demos/Illum/IBRBillboardCloudTrees/OGRE/IBRTreesOGRE/media/general/indirectTexturingLighting_hlsl_FP20.shd @ 1493

sampler indirectTexture: register(s0);
sampler sourceTexture: register(s1);

uniform float epsilonX;
uniform float epsilonY;
uniform float sourceTextureSize;
uniform float numSamples;
uniform float sqrtNumSamples;
uniform float3 ambientColor;
uniform float ambient;

float4 main_fp(float2 texCoord: TEXCOORD0, 
               float2 subTexCoord: TEXCOORD1,
               float diffuseIn  : TEXCOORD2) : COLOR
{
   float4 ocolor = float4(0.0, 0.0, 0.0, 0.0);
   float2 epsilon = float2(epsilonX, epsilonY);
   float4 value = tex2D(indirectTexture, subTexCoord).xyzw;
   float2 coords = float2(0.0, 1.0) - abs(texCoord - ( value.xy - epsilon ) );

   if (value.w != 0.0) 
   {    
        float2 newcoord = (float2(1.0, 1.0) - value.zw) + ((coords * sourceTextureSize) / sqrtNumSamples);
        ocolor = float4(tex2D(sourceTexture, newcoord).xyzw);
        ocolor.xyz = (ambientColor * ambient * 0.000001) + (ocolor.xyz * diffuseIn);
   }
   
   return  ocolor;
}