// identity 
float time=0;
float sampleDist = 1.0f/512.0f;  // distance one pixel in u/v

sampler2D image : register(s0);


float4 main(
	float4 Pos : POSITION,
	float2 texCoord: TEXCOORD0) : COLOR 
{
	float4 img = tex2D(image, texCoord);

	// convert to gray 
	float4 sum = dot(img, float4(0.30f, 0.59f, 0.11f, 0.0f));
	
	sum.a=img.a; // keep alpha
	return lerp(img,sum,time);	 
}