#include "common.h"
#include "shared\waterconfig.h"

struct v2p
{
	float2 tbase	: TEXCOORD0;
	float2 tdist0	: TEXCOORD1;
	float2 tdist1	: TEXCOORD2;
#ifdef	USE_SOFT_WATER
#ifdef	NEED_SOFT_WATER
	float4	tctexgen: TEXCOORD3;
#endif	//	USE_SOFT_WATER
#endif	//	NEED_SOFT_WATER	
	float4 hpos		: SV_Position;
};

Texture2D        s_distort;
#define POWER        .5h
//////////////////////////////////////////////////////////////////////////////////////////
// Pixel
float4 main( v2p I ) : SV_Target
{
//	float4	t_base	= tex2D( s_base, I.tbase  );
	float4	t_base	= s_base.Sample( smp_base, I.tbase  );

//	float2	t_d0	= tex2D( s_distort, I.tdist0 );
//	float2	t_d1	= tex2D( s_distort, I.tdist1 );
	float2	t_d0	= s_distort.Sample( smp_base, I.tdist0 );
	float2	t_d1	= s_distort.Sample( smp_base, I.tdist1 );
	float2	distort	= (t_d0+t_d1)*0.5;                      // average
	float2	zero	= float2( 0.5, 0.5 );
	float2	faded	= lerp( distort, zero, t_base.a );

	//	Igor: additional depth test
#ifdef	USE_SOFT_WATER
#ifdef	NEED_SOFT_WATER
	float	alphaDistort;
//	float4	_P	= tex2Dproj         (s_position,         I.tctexgen);
	float2 PosTc = I.tctexgen.xy/I.tctexgen.z;
#ifdef GBUFFER_OPTIMIZATION
	gbuffer_data gbd = gbuffer_load_data( PosTc, I.hpos );
#else
	gbuffer_data gbd = gbuffer_load_data( PosTc );
#endif
	//float4 _P = 	s_position.Sample( smp_nofilter, PosTc);
	float4 _P = 	float4( gbd.P, gbd.mtl );
	float 	waterDepth = _P.z-I.tctexgen.z;
	alphaDistort = saturate(5*waterDepth);
	faded 	= lerp  ( zero, faded, alphaDistort);
#endif	//	NEED_SOFT_WATER
#endif	//	USE_SOFT_WATER & NEED_SOFT_WATER

	float2	faded_bx2	= (faded*2-1)*W_DISTORT_POWER;
	float	faded_dot	= dot        (float3(faded_bx2,0),.75        );        //0.75
	float	alpha		= .5f        ;                //abs          (faded_dot);


	faded	= faded*POWER - .5*POWER + 0.5        ;

        // out
	//	Igor: need for alpha water
#ifdef	NEED_SOFT_WATER
	return  float4( faded, 0.0h, alpha );
#else	//	NEED_SOFT_WATER
	return  float4( faded, .08h, alpha );
#endif	//	NEED_SOFT_WATER
}