/* --- Vibrance settings --- */
#define Vibrance 0.40 //Intelligently saturates (or desaturates if you use negative values) the pixels depending on their original saturation.
/* --- Defining Constants --- */
sampler s0 : register(s0);
/* --- Vibrance --- */
/*
by Christian Cann Schuldt Jensen ~ CeeJay.dk
Vibrance intelligently boosts the saturation of pixels
so pixels that had little color get a larger boost than pixels that had a lot.
This avoids oversaturation of pixels that were already very saturated.
*/
float4 VibrancePass( float4 colorInput )
{
float4 color = colorInput; //original input color
float3 lumCoeff = float3(0.2126, 0.7152, 0.0722); //Values to calculate luma with
float luma = dot(lumCoeff, color.rgb); //calculate luma (grey)
float max_color = max(max(colorInput.r,colorInput.g),colorInput.b); //Find the strongest color
float min_color = min(min(colorInput.r,colorInput.g),colorInput.b); //Find the weakest color
float color_saturation = max_color - min_color; //The difference between the two is the saturation
//color = lerp(luma, color, (1.0 + (Vibrance * (1.0 - color_saturation)))); //extrapolate between luma and original by 1 + (1-saturation)
color = lerp(luma, color, (1.0 + (Vibrance * (1.0 - (sign(Vibrance) * color_saturation))))); //extrapolate between luma and original by 1 + (1-saturation)
return color; //return the result
//return color_saturation.xxxx; //Visualize the saturation
}
/* --- Main --- */
float4 main(float2 tex : TEXCOORD0) : COLOR {
float4 c0 = tex2D(s0, tex);
c0 = VibrancePass(c0);
return c0;
}