//  STATIC: "HALFLAMBERT"			"0..1"
//	DYNAMIC: "LIGHT_COMBO"			"0..21"
//	DYNAMIC: "DOWATERFOG"			"0..1"
//	DYNAMIC: "NUM_BONES"			"0..3"

#include "common_vs_fxc.h"

#ifdef USE_CONDITIONALS
const bool g_bZeroBones : register( b0 );
const bool g_bOneBone   : register( b1 );
const bool g_bTwoBones  : register( b2 );
#else
static const int g_NumBones			= NUM_BONES;
#endif

static const int g_LightCombo		= LIGHT_COMBO;
static const int g_FogType			= DOWATERFOG;
static const int g_LocalLightType0	= g_LocalLightType0Array[g_LightCombo];
static const int g_LocalLightType1	= g_LocalLightType1Array[g_LightCombo];

const float4 cBaseTexCoordTransform[2]	:  register( SHADER_SPECIFIC_CONST_0 );

//-----------------------------------------------------------------------------
// Input vertex format
//-----------------------------------------------------------------------------
struct VS_INPUT
{
	// This is all of the stuff that we ever use.
	float4 vPos				: POSITION;
	float4 vBoneWeights		: BLENDWEIGHT;
	float4 vBoneIndices		: BLENDINDICES;
	float3 vNormal			: NORMAL;
	float4 vColor			: COLOR0;
	float3 vSpecular		: COLOR1;
	// make these float2's and stick the [n n 0 1] in the dot math.
	float4 vTexCoord0		: TEXCOORD0;
	float4 vTexCoord1		: TEXCOORD1;
	float4 vTexCoord2		: TEXCOORD2;
	float4 vTexCoord3		: TEXCOORD3;
	float3 vTangentS		: TANGENT;
	float3 vTangentT		: BINORMAL;
	float4 vUserData		: TANGENT;

	// Position and normal/tangent deltas
	float3 vPosFlex			: POSITION1;
	float3 vNormalFlex		: NORMAL1;
};


//-----------------------------------------------------------------------------
// Output vertex format
//-----------------------------------------------------------------------------
struct VS_OUTPUT
{
	// stuff that isn't seen by the pixel shader
    float4 projPos					: POSITION;	
	float  fog						: FOG;

	// stuff for the pixel shader
	HALF4 baseTexCoord2_tangentSpaceVertToEyeVectorXY	: TEXCOORD0;

	// bump mapping and a separate envmap mask texture are mutually exclusive.
	float3 color2						: TEXCOORD1;
	float3 color1						: TEXCOORD2;
	float4 worldVertToEyeVectorXYZ_tangentSpaceVertToEyeVectorZ	: TEXCOORD3;
	float3x3 tangentSpaceTranspose		: TEXCOORD4;

	float4 worldPos_projPosZ			: TEXCOORD7;

	float4 fogFactorW					: COLOR1;
};


//-----------------------------------------------------------------------------
// Main shader entry point
//-----------------------------------------------------------------------------
VS_OUTPUT main( const VS_INPUT v )
{
	VS_OUTPUT o = ( VS_OUTPUT )0;

	float4 vPosition = v.vPos;
	float3 vNormal   = v.vNormal;
	float4 vTangent  = v.vUserData;

	// Flexes coming in from a separate stream (contribution masked by cFlexScale.x)
	vPosition.xyz += v.vPosFlex    * cFlexScale.x;
	vNormal       += v.vNormalFlex * cFlexScale.x;
	vTangent.xyz  += v.vNormalFlex * cFlexScale.x; // Tangent uses normal deltas

	// Perform skinning
	float3 worldNormal, worldPos, worldTangentS, worldTangentT;
	SkinPositionNormalAndTangentSpace( 
		g_NumBones, 
		vPosition, vNormal, vTangent,
		v.vBoneWeights, v.vBoneIndices,
		worldPos, worldNormal, worldTangentS, worldTangentT );

	// Always normalize since flex path is controlled by runtime
	// constant not a shader combo and will always generate the normalization
	worldNormal   = normalize( worldNormal );
	worldTangentS = normalize( worldTangentS );
	worldTangentT = normalize( worldTangentT );

	// Transform into projection space
	float4 projPos = mul( float4( worldPos, 1 ), cViewProj );
	o.projPos = projPos;
	o.fogFactorW = o.fog = CalcFog( worldPos, projPos, g_FogType );

 	// Needed for water fog alpha and diffuse lighting 
	// FIXME: we shouldn't have to compute this all the time.
	o.worldPos_projPosZ = float4( worldPos, projPos.z );

	// Needed for cubemapping + parallax mapping
	// FIXME: We shouldn't have to compute this all the time.
	o.worldVertToEyeVectorXYZ_tangentSpaceVertToEyeVectorZ.xyz = VSHADER_VECT_SCALE * (cEyePos - worldPos);

	// Compute bumped lighting
	// FIXME: We shouldn't have to compute this for unlit materials
	o.color1.xyz = GetVertexColorForLight( worldPos, worldNormal, 0, g_LocalLightType0 );
	o.color2.xyz = GetVertexColorForLight( worldPos, worldNormal, 1, g_LocalLightType1 );

	// Base texture coordinate transform
	o.baseTexCoord2_tangentSpaceVertToEyeVectorXY.x = dot( v.vTexCoord0, cBaseTexCoordTransform[0] );
	o.baseTexCoord2_tangentSpaceVertToEyeVectorXY.y = dot( v.vTexCoord0, cBaseTexCoordTransform[1] );

	// Tangent space transform
	o.tangentSpaceTranspose[0] = float3( worldTangentS.x, worldTangentT.x, worldNormal.x );
	o.tangentSpaceTranspose[1] = float3( worldTangentS.y, worldTangentT.y, worldNormal.y );
	o.tangentSpaceTranspose[2] = float3( worldTangentS.z, worldTangentT.z, worldNormal.z );

	return o;
}