/***************************************************************************************/
/*! DopeShader settings available in \file APB-DopeShader-Settings.usf
****************************************************************************************/

#include "Common.usf"
#include "PostProcessCommon.usf"
#include "APB-DopeShader-Settings.usf"

// Tone-mapping parameters.
sampler2D AdaptedLuminance;

#if SET_BLOOM
	sampler2D BlurredImage;
	float BloomAlpha;
	float BloomPostScale;
#endif

// Colour adjustment parameters.
#if SET_ADJUSTMENT
	float Brightness;
	float Contrast;
	float Saturation;
	float3 DesaturatedColour;
#endif

// The per-color weighting to be used for luminance calculations in RGB order.
static const float3 LuminanceVector = float3(0.2126, 0.7152, 0.0722); // (0.2126, 0.7152, 0.0722) or (0.3, 0.59, 0.11)
static const float WHITE = pow( 1, 2 );

// SJT: Perform tone mapping on a pixel.
float3 ToneMap(float3 WorldColour)
{
    float fAdaptedLuminance = tex2D(AdaptedLuminance, float2(0.5f, 0.5f)).r;
    float lum = dot(WorldColour, LuminanceVector);
	lum = ((lum * (lum / WHITE)) / lum) * (0.75f / fAdaptedLuminance) * 8;
	WorldColour *= lum;
	return saturate( WorldColour );
}

// SJT: Basic colour adjustment.
#if SET_ADJUSTMENT
	float3 ColourAdjust(float3 InColour)
	{
		float3 Result = InColour;

		// Saturate before we do anything to prevent whackiness from values outside [0,1]
		Result = saturate(Result);

		// (De)saturate.
		Result = lerp(dot(Result, LuminanceVector) * DesaturatedColour, Result, Saturation);

		// Contrast adjustment (cubic).
		Result = Result - Contrast * (Result - 1) * Result * (Result - 0.5);

		// Brightness adjustment (addition).
		Result = Result + Brightness;

		return Result;
	}
#endif

void Main(
	in float2 UV : TEXCOORD0,
	in float2 SceneUV : TEXCOORD1,
	out float4 OutColor : COLOR0
	)
{
	float4 sceneColor=tex2D(SceneColorTexture,SceneUV);

	#if SET_BLOOM
		float4 rawColor = tex2D(BlurredImage,UV);
		float3 filteredColor = MAX_SCENE_COLOR * rawColor.rgb * BloomPostScale;
		float3 RTWBloom = 1-(saturate(1-(filteredColor.rgb*BloomAlpha*0.5))*saturate(1-lerp(sceneColor.rgb, 0, BloomAlpha*saturate(rawColor.a*4)*0.5)));
		float3 ToneMappedColour = ToneMap(RTWBloom);
	#else
		float3 ToneMappedColour = ToneMap(sceneColor);
	#endif

	#if SET_ADJUSTMENT
		float3 AdjustedColour = ColourAdjust(ToneMappedColour);
		OutColor = float4(AdjustedColour.rgb, sceneColor.a);
	#else
		OutColor = float4(ToneMappedColour.rgb, sceneColor.a);
	#endif

	#if SET_DESATURATE
		float luminance = dot(OutColor, LuminanceVector);
		float4 eColor = lerp(luminance, OutColor, 0.9) ; // 1.0 no desaturation, while 0.0 is full desaturation
		OutColor = float4(eColor.rgb, OutColor.a);
	#endif

	OutColor = pow( OutColor, 1/1.5f );
}