//
// Copyright (c) Andrew Porter. All Rights Reserved.
// License: https://github.com/ServiRegis/Licenses/blob/master/CODEX-CREATIVUS-ET-PUBLICUS.txt
//


#define LUMA_COEFFICIENT float3(0.2126f, 0.7152f, 0.0722f)

void main() {
    float4 screen = Sample();
    screen.a = dot(screen.rgb, LUMA_COEFFICIENT);
    // chroma
    screen.rgb = screen.rgb - screen.a;
    // luma
    screen.a = screen.a - 2.0f;
    screen.a = screen.a * screen.a;
    screen.a = 1.0f / screen.a - 0.25f;
    screen.a = sqrt(screen.a);
    screen.a *= 1.1547005383792515290182975610039f;
       
    screen.rgb = screen.rgb + screen.a;
    
    SetOutput(screen);
}