//====== Copyright © 1996-2004, Valve Corporation, All rights reserved. =======
//
// Purpose: 
//
//=============================================================================

// STATIC: "CONVERT_TO_SRGB"				"0..1"	[ps20b][= g_pHardwareConfig->NeedsShaderSRGBConversion()] [PC]
// STATIC: "CONVERT_TO_SRGB"				"0..1"	[ps30][= g_pHardwareConfig->NeedsShaderSRGBConversion()] [PC]
// STATIC: "CONVERT_TO_SRGB"				"0..0"	[= 0] [XBOX]

// DYNAMIC: "PIXELFOGTYPE"					"0..1"
// DYNAMIC: "WRITE_DEPTH_TO_DESTALPHA"		"0..1"	[ps20b] [PC]
// DYNAMIC: "WRITE_DEPTH_TO_DESTALPHA"		"0..0"	[ps20b] [XBOX]
// DYNAMIC: "WRITE_DEPTH_TO_DESTALPHA"		"0..1"	[ps30]


#if defined( SHADER_MODEL_PS_2_0 )
#	define WRITE_DEPTH_TO_DESTALPHA 0
#endif

#include "common_ps_fxc.h"
#include "shader_constant_register_map.h"

sampler BaseTextureSampler			: register( s0 );

const float4 g_FogParams				: register( PSREG_FOG_PARAMS );
const float4 g_EyePos_SpecExponent		: register( PSREG_EYEPOS_SPEC_EXPONENT );

struct PS_INPUT
{
	float2 baseTexCoord				: TEXCOORD0;
	float3 vertAtten				: TEXCOORD1;
	
	float4 worldPos_projPosZ		: TEXCOORD7;		// Necessary for pixel fog
};

float4 main( PS_INPUT i ) : COLOR
{
	float4 baseSample = tex2D( BaseTextureSampler, i.baseTexCoord );
	
	float4 result;
	result.xyz = baseSample.xyz * i.vertAtten;
	result.a = baseSample.a;
	
	
	float fogFactor = CalcPixelFogFactor( PIXELFOGTYPE, g_FogParams, g_EyePos_SpecExponent.z, i.worldPos_projPosZ.z, i.worldPos_projPosZ.w );
	return FinalOutput( result, fogFactor, PIXELFOGTYPE, TONEMAP_SCALE_LINEAR, (WRITE_DEPTH_TO_DESTALPHA != 0), i.worldPos_projPosZ.w );
}