sampler SceneSampler : register(s0) = sampler_state
{    
    MinFilter = Linear;
    MagFilter = Linear;
    
    AddressU = Clamp;
    AddressV = Clamp;
};

float ValueShift=0;
float HueStrength=1;

float4 PS(float2 tc : TEXCOORD0) : COLOR0
{
	float4 color = tex2D(SceneSampler, tc);
	float rg = color.y-color.x;
	float rb = color.z-color.x;
    float4 ret = float4(color.x+ValueShift,color.x+ValueShift,color.x+ValueShift,color.w);
    ret.y+=rg*HueStrength;
    ret.z+=rb*HueStrength;
    return ret;
}

technique Gamma
{
    pass pass0
    {
        PixelShader = compile ps_2_0 PS();
    }
}