// STATIC: "HASALPHAMASK"		"0..1"
// STATIC: "HASSTATICTEXTURE"	"0..1"
// STATIC: "USEALTERNATEVIEW"	"0..1"

// DYNAMIC: "SKINNING"			"0..1"
// DYNAMIC: "ADDSTATIC"			"0..1" 

#define USESTATICTEXTURE (((ADDSTATIC == 1) && (HASSTATICTEXTURE == 1)))

#include "common_vs_fxc.h"

static const bool g_bSkinning = SKINNING ? true : false;

#if ( USEALTERNATEVIEW == 1 )
const float4x4 g_CustomViewProj	: register( SHADER_SPECIFIC_CONST_0 );
#endif

const float4 g_vViewportMad : register( SHADER_SPECIFIC_CONST_4 );
const float g_vIsRecursivePortalView : register( SHADER_SPECIFIC_CONST_5 );

struct VS_INPUT
{
	float4 vPos							: POSITION;
	float4 vNormal						: NORMAL;
	float4 vBoneWeights					: BLENDWEIGHT;
	float4 vBoneIndices					: BLENDINDICES;
	float2 vMappingTexCoord				: TEXCOORD0;
	float  flDecalOffset				: TEXCOORD1;	// How far to move each vertex along the normal
};


struct VS_OUTPUT
{
	float4 vProjPos					: POSITION;
	float3 vPortalTexCoord			: TEXCOORD0;

	#if( (HASALPHAMASK == 1) || (USESTATICTEXTURE) )
		float2 vSecondaryTexCoord		: TEXCOORD1;
		#if( (HASALPHAMASK == 1) && (USESTATICTEXTURE) )
			float2 vTertiaryTexCoord		: TEXCOORD2;
		#endif
	#endif

	#if !defined( _X360  ) && !defined( SHADER_MODEL_VS_3_0 )
		float fog						: FOG;
	#endif

	float4 worldPos_projPosZ		: TEXCOORD7;		// Necessary for pixel fog
};


VS_OUTPUT main( const VS_INPUT v )
{
	VS_OUTPUT o = ( VS_OUTPUT )0;
	
	float3 worldPos;
	
	// Move the portal decal away from the base surface a bit to avoid z fighting
	float3 vObjNormal;
	DecompressVertex_Normal( v.vNormal, vObjNormal );
	float4 vObjPos = v.vPos.xyzw;
	float flDecalOffset = 1.0f;	// This offset is used in recursive portal views when using fast clipping (e.g. on the PS3).
								// It prevents ugly Z fighting between the portal and the surface it's on due to reduced Z precision when
								// a player is really really close to a portal.
	if ( g_vIsRecursivePortalView == 0.0f )
	{
		flDecalOffset = v.flDecalOffset;
	}
	vObjPos.xyz += flDecalOffset * vObjNormal.xyz;

	SkinPosition( 
			g_bSkinning, 
			vObjPos,
			v.vBoneWeights, v.vBoneIndices,
			worldPos );
			
	float4 vTextureProjectedPos;
			
	o.vProjPos = mul( float4( worldPos, 1 ), cViewProj );
	
	#ifdef _PS3
	{
		// Account for OpenGL's flipped y coordinate and expanded z range [-1,1] instead of [0,1]
		o.vProjPos.y = -o.vProjPos.y;
		o.vProjPos.z = 2.0f * o.vProjPos.z - o.vProjPos.w;
	}
	#endif // _PS3

	#if ( USEALTERNATEVIEW == 1 )
	{
		vTextureProjectedPos = mul( float4( worldPos, 1 ), g_CustomViewProj );	
	}
	#else	
	{
		vTextureProjectedPos = o.vProjPos;
	}
	#endif
	
	#if !defined( _X360 ) && !defined( SHADER_MODEL_VS_3_0 )
	{
		o.fog = CalcFixedFunctionFog( worldPos, FOGTYPE_RANGE );
	}
	#endif

	o.worldPos_projPosZ = float4( worldPos.xyz, o.vProjPos.z );
	
	//Screen coordinates mapped back to texture coordinates for the portal texture
	o.vPortalTexCoord.x = vTextureProjectedPos.x;
	o.vPortalTexCoord.y = -vTextureProjectedPos.y; // invert Y
	o.vPortalTexCoord.xy = (o.vPortalTexCoord.xy + vTextureProjectedPos.w) * 0.5f;
	o.vPortalTexCoord.z = vTextureProjectedPos.w;
	
	#if ( USEALTERNATEVIEW == 1 )
	{
		o.vPortalTexCoord.xy = saturate( o.vPortalTexCoord.xy / vTextureProjectedPos.w ) * vTextureProjectedPos.w; //stretch instead of clipping.
	}
	#endif
	
	//handle non-fullscreen viewports
	o.vPortalTexCoord.xy = ( ( ( o.vPortalTexCoord.xy / vTextureProjectedPos.w ) * g_vViewportMad.xy ) + g_vViewportMad.zw ) * vTextureProjectedPos.w; //handle non-fullscreen viewports	
	
	#if( (HASALPHAMASK == 1) || (USESTATICTEXTURE) )
	{
		o.vSecondaryTexCoord = v.vMappingTexCoord.xy;
		#if( (HASALPHAMASK == 1) && (USESTATICTEXTURE) )
		{
			o.vTertiaryTexCoord = v.vMappingTexCoord.xy;
		}
		#endif
	}
	#endif

	return o;
}