////////////////////////////////////////////////////////
//	GTU-famicom version 0.50
//	Author: aliaspider - aliaspider@gmail.com
//	License: GPLv3
////////////////////////////////////////////////////////

#pragma parameter noScanlines "no scanlines" 0.0 0.0 1.0 1.0
#pragma parameter tvVerticalResolution "tv vertical resolution" 250.0 20.0 1000.0 10.0
#pragma parameter blackLevel "black level" 0.07 -0.30 0.30 0.01
#pragma parameter contrast "contrast" 1.0 0.0 2.0 0.1
#pragma parameter gamma "gamma" 1.0 0.5 1.5 0.01

#include "config.h"

#ifdef PARAMETER_UNIFORM
uniform float cropOverscan;
uniform float noScanlines;
uniform float tvVerticalResolution;
uniform float blackLevel;
uniform float contrast;
uniform float gamma;
#endif

void main_vertex
(
   float4 position : POSITION,
   out float4 oPosition : POSITION,
   uniform float4x4 modelViewProj,
   float2 tex : TEXCOORD,
   out float2 oTex : TEXCOORD
)
{
	oPosition = mul(modelViewProj, position);
	if(cropOverscan)
		oPosition.y/=(224.0/240.0);

	oTex = tex;
}

struct input
{
   float2 video_size;
   float2 texture_size;
   float2 output_size;
   float  frame_count;
   float  frame_direction;
   float frame_rotation;
};



#define pi			3.14159265358
#define normalGauss(x) ((exp(-(x)*(x)*0.5))/sqrt(2.0*pi))
float normalGaussIntegral(float x)
{
	float a1 = 0.4361836;
	float a2 = -0.1201676;
	float a3 = 0.9372980;
	float p = 0.3326700;
	float t = 1.0 / (1.0 + p*abs(x));
	return (0.5-normalGauss(x) * (t*(a1 + t*(a2 + a3*t))))*sign(x);
}


float3 scanlines( float x , float3 c,input IN){
	float temp=sqrt(2*pi)*(tvVerticalResolution/IN.video_size.y);

	float rrr=0.5*(IN.video_size.y/IN.output_size.y);
	float x1=(x+rrr)*temp;
	float x2=(x-rrr)*temp;
	c.r=(c.r*(normalGaussIntegral(x1)-normalGaussIntegral(x2)));
	c.g=(c.g*(normalGaussIntegral(x1)-normalGaussIntegral(x2)));
	c.b=(c.b*(normalGaussIntegral(x1)-normalGaussIntegral(x2)));
	c*=(IN.output_size.y/IN.video_size.y);
	return c;
}

#define Y(j) (offset.y-(j))
#define a(x) abs(x)
#define d(x,b) (pi*b*min(a(x)+0.5,1.0/b))
#define e(x,b) (pi*b*min(max(a(x)-0.5,-1.0/b),1.0/b))
#define STU(x,b) ((d(x,b)+sin(d(x,b))-e(x,b)-sin(e(x,b)))/(2.0*pi))

#define SOURCE(j) float2(tex.x,tex.y - Y(j)/IN.texture_size.y)
#define C(j) (tex2D(s0, SOURCE(j)).xyz)

#define VAL(j) (C(j)*STU(Y(j),(tvVerticalResolution/IN.video_size.y)))
#define VAL_scanlines(j) (scanlines(Y(j),C(j),IN))


float4 main_fragment (float2 tex : TEXCOORD, uniform sampler2D s0 : TEXUNIT0, uniform input IN) : COLOR
{
	float2	offset	= fract((tex.xy * IN.texture_size.xy) - 0.5);
	float3	tempColor = float3(0.0);

	float i;
//	for (i=-range;i<range+2.0;i++){

#define SCALEY_RANGE 2

   if (noScanlines)
      for (i = 1.0 - SCALEY_RANGE; i < 1.0 + SCALEY_RANGE; i++)
         tempColor+=VAL(i);
   else
      for (i = 1.0 - SCALEY_RANGE; i < 1.0 + SCALEY_RANGE; i++)
         tempColor+=VAL_scanlines(i);


	tempColor-=float3(blackLevel);
	tempColor*=(contrast/float3(1.0-blackLevel));
	tempColor=pow(tempColor,float3(gamma));
	return float4(tempColor, 1.0);

}
