/*
Bug test Vector * Matrix
*/

  ////////////////////
 /////// MENU ///////
////////////////////

uniform int API <
	ui_tooltip = "To see right result change API";
	ui_type = "combo";
	ui_items = "Now Im using DirectX\0Now Im using OpenGL\0";
> = 0;

uniform int Coefficients <
	ui_label = "YUV coefficients";
	ui_tooltip = "For digital signal use BT.709, analog (like VGA) use BT.601";
	ui_type = "combo";
	ui_items = "BT.709\0BT.601\0";
> = 0;

  //////////////////////
 /////// SHADER ///////
//////////////////////

#include "ReShade.fxh"

// RGB to YUV709
static const float3x3 ToYUV709 =
float3x3(
	float3(0.2126, 0.7152, 0.0722),
	float3(-0.09991, -0.33609, 0.436),
	float3(0.615, -0.55861, -0.05639)
);
// RGB to YUV601
static const float3x3 ToYUV601 =
float3x3(
	float3(0.299, 0.587, 0.114),
	float3(-0.14713, -0.28886, 0.436),
	float3(0.615, -0.51499, -0.10001)
);
// YUV709 to RGB
static const float3x3 ToRGB709 =
float3x3(
	float3(1, 0, 1.28033),
	float3(1, -0.21482, -0.38059),
	float3(1, 2.12798, 0)
);
// YUV601 to RGB
static const float3x3 ToRGB601 =
float3x3(
	float3(1, 0, 1.13983),
	float3(1, -0.39465, -0.58060),
	float3(1, 2.03211, 0)
);

// Shader
void RGB_YUV_RGB_PS(float4 vois : SV_Position, float2 texcoord : TexCoord, out float3 Display : SV_Target)
{
	bool YUV709 = (Coefficients == 0);
	bool OK = (API == 0);

	// Sample display image
	// Convert to YUV
	Display = OK ?
		mul(YUV709 ? ToYUV709 : ToYUV601, tex2D(ReShade::BackBuffer, texcoord).rgb)
		:
		mul(tex2D(ReShade::BackBuffer, texcoord).rgb, YUV709 ? ToYUV709 : ToYUV601)
	;

	Display.x *= 0.5; // Changing image Luma

	// Convert YUV to RGB
	Display = OK ?
		mul(YUV709 ? ToRGB709: ToRGB601, Display)
		:
		mul(Display, YUV709 ? ToRGB709: ToRGB601)
	;
}

technique RGB_YUV_RGB
{
	pass
	{
		VertexShader = PostProcessVS;
		PixelShader = RGB_YUV_RGB_PS;
	}
}