w

uniform float LumaRed <
	ui_label = "Red Exposure";
	ui_type = "drag";
	ui_min = -10.0; ui_max = 10.0; ui_step = 0.001;
> = 0.0;

uniform float LumaOrange <
	ui_label = "Orange Exposure";
	ui_type = "drag";
	ui_min = -10.0; ui_max = 10.0; ui_step = 0.001;
> = 0.0;

uniform float LumaYellow <
	ui_label = "Yellow Exposure";
	ui_type = "drag";
	ui_min = -10.0; ui_max = 10.0; ui_step = 0.001;
> = 0.0;

uniform float LumaGreen <
	ui_label = "Green Exposure";
	ui_type = "drag";
	ui_min = -10.0; ui_max = 10.0; ui_step = 0.001;
> = 0.0;

uniform float LumaAqua <
	ui_label = "Light Blue Exposure";
	ui_type = "drag";
	ui_min = -10.0; ui_max = 10.0; ui_step = 0.001;
> = 0.0;

uniform float LumaBlue <
	ui_label = "Blue Exposure";
	ui_type = "drag";
	ui_min = -10.0; ui_max = 10.0; ui_step = 0.001;
> = 0.0;

uniform float LumaMagenta <
	ui_label = "Magenta Exposure";
	ui_type = "drag";
	ui_min = -10.0; ui_max = 10.0; ui_step = 0.001;
> = 0.0;

#include "ReShade.fxh"

float3 RGB2HCV(in float3 RGB)
{
	RGB = saturate(RGB);
	float Epsilon = 1e-10;
    	// Based on work by Sam Hocevar and Emil Persson
    	float4 P = (RGB.g < RGB.b) ? float4(RGB.bg, -1.0, 2.0/3.0) : float4(RGB.gb, 0.0, -1.0/3.0);
    	float4 Q = (RGB.r < P.x) ? float4(P.xyw, RGB.r) : float4(RGB.r, P.yzx);
    	float C = Q.x - min(Q.w, Q.y);
    	float H = abs((Q.w - Q.y) / (6 * C + Epsilon) + Q.z);
    	return float3(H, C, Q.x);
}

float3 RGB2HSL(in float3 RGB)
{
    	float3 HCV = RGB2HCV(RGB);
    	float L = HCV.z - HCV.y * 0.5;
    	float S = HCV.y / (1.0000001 - abs(L * 2 - 1));
    	return float3(HCV.x, S, L);
}

float3 HSL2RGB(in float3 HSL)
{
	HSL = saturate(HSL);
	//HSL.z *= 0.99;
    	float3 RGB = saturate(float3(abs(HSL.x * 6.0 - 3.0) - 1.0,2.0 - abs(HSL.x * 6.0 - 2.0),2.0 - abs(HSL.x * 6.0 - 4.0)));
    	float C = (1 - abs(2 * HSL.z - 1)) * HSL.y;
    	return (RGB - 0.5) * C + HSL.z;
}

float4 MainPS(float4 vpos : SV_Position, float2 texcoord : TexCoord) : SV_Target
{
	float4 color = tex2D(ReShade::BackBuffer, texcoord);

        float3 HSL = RGB2HSL(color.rgb);

        float huemults[7] =
	{
	/*red*/	max(saturate(1.0 - abs(HSL.x*12.0)), saturate(1.0 - abs((HSL.x-12.0/12)* 6.0))),
     /*orange*/ saturate(1.0 - abs((HSL.x-1.0/12)*12.0)),
     /*yellow*/	max(saturate(1.0 - abs((HSL.x-2.0/12)*12.0))*step(HSL.x,2.0/12.0), saturate(1.0 - abs((HSL.x-2.0/12)* 6.0))*step(2.0/12.0,HSL.x)),
      /*green*/ saturate(1.0 - abs((HSL.x-4.0/12)* 6.0)),
       /*aqua*/ saturate(1.0 - abs((HSL.x-6.0/12)* 6.0)),
       /*blue*/ saturate(1.0 - abs((HSL.x-8.0/12)* 6.0)),
    /*magenta*/ saturate(1.0 - abs((HSL.x-10.0/12)* 6.0))
	};

        float colorgray = 0;
        colorgray += huemults[0] * HSL.z * exp2(LumaRed);
        colorgray += huemults[1] * HSL.z * exp2(LumaOrange);
        colorgray += huemults[2] * HSL.z * exp2(LumaYellow);
        colorgray += huemults[3] * HSL.z * exp2(LumaGreen);
        colorgray += huemults[4] * HSL.z * exp2(LumaAqua);
        colorgray += huemults[5] * HSL.z * exp2(LumaBlue);
        colorgray += huemults[6] * HSL.z * exp2(LumaMagenta);

        return colorgray;

}

technique AchromatopsiaHelper
{
	pass
	{
		VertexShader = PostProcessVS;
		PixelShader = MainPS;
	}
}