UnifyLODs.cpp #1

//========= Copyright  1996-2005, Valve Corporation, All rights reserved. ============//
//
// Purpose: 
//
// $NoKeywords: $
//
//=============================================================================//
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <math.h>
#include <float.h>

#include "cmdlib.h"
#include "scriplib.h"
#include "mathlib.h"
#include "studio.h"
#include "studiomdl.h"
#include "bone_setup.h"
#include "vstdlib/strtools.h"
#include "vmatrix.h"
#include "optimize.h"

// debugging only - enabling turns off remapping to create all lod vertexes as unique
// to ensure remapping logic does not introduce collapse anomalies
//#define UNIQUE_VERTEXES_FOR_LOD

//-----------------------------------------------------------------------------
// Forward declarations local to this file
//-----------------------------------------------------------------------------
class CVertexDictionary;
struct VertexInfo_t;

void ValidateBoneWeights( const s_source_t *pSrc );
void ValidateBoneWeight( const s_boneweight_t &boneWeight );
void SortBoneWeightByIndex( s_boneweight_t &boneWeight );
int FindVertexInDictionaryExact( CVertexDictionary &vertexDict, int nStartVert, int nEndVert, const VertexInfo_t &vertex );
static void BuildBoneLODMapping( CUtlVector<int> &boneMap, int lodID );


//-----------------------------------------------------------------------------
// A vertex format
//-----------------------------------------------------------------------------
struct VertexInfo_t
{
	Vector			m_Position;
	Vector			m_Normal;
	Vector2D		m_TexCoord;
	Vector4D		m_TangentS;
	s_boneweight_t	m_BoneWeight;
	int				m_bLoD;
};


//-----------------------------------------------------------------------------
// Stores all vertices in the vertex dictionary
//-----------------------------------------------------------------------------
class CVertexDictionary
{
public:
	CVertexDictionary();

	// Adds a vertex to the dictionary
	int AddVertex( const VertexInfo_t &srcVertex );
	int AddVertexFromSource( const s_source_t *pSrc, int nVertexIndex );

	// Iteration
	int VertexCount() const;
	VertexInfo_t &Vertex( int i );
	const VertexInfo_t &Vertex( int i ) const;

	int RootLODVertexStart() const;
	int RootLODVertexEnd() const;

	// Gets the vertex count for the previous LOD
	int PrevLODVertexCount() const;

	// Marks the dictionary as starting defining vertices for a new LOD
	void StartNewLOD();

	void SetRootVertexRange( int start, int end );

private:
	CUtlVector<VertexInfo_t>	m_Verts;
	int							m_nPrevLODCount;
	int							m_nRootLODStart;
	int							m_nRootLODEnd;
};


//-----------------------------------------------------------------------------
// Copies in a particular vertex from the s_source_t
//-----------------------------------------------------------------------------
CVertexDictionary::CVertexDictionary()
{
	m_nPrevLODCount = 0;
}


//-----------------------------------------------------------------------------
// Accessor
//-----------------------------------------------------------------------------
inline VertexInfo_t &CVertexDictionary::Vertex( int i )
{
	return m_Verts[i];
}

inline const VertexInfo_t &CVertexDictionary::Vertex( int i ) const
{
	return m_Verts[i];
}

	
//-----------------------------------------------------------------------------
// Gets the vertex count for the previous LOD
//-----------------------------------------------------------------------------
inline int CVertexDictionary::PrevLODVertexCount() const
{
	return m_nPrevLODCount;
}


inline int CVertexDictionary::RootLODVertexStart() const
{
	return m_nRootLODStart;
}


inline int CVertexDictionary::RootLODVertexEnd() const
{
	return m_nRootLODEnd;
}

	
//-----------------------------------------------------------------------------
// Marks the dictionary as starting defining vertices for a new LOD
//-----------------------------------------------------------------------------
void CVertexDictionary::StartNewLOD()
{
	m_nPrevLODCount = VertexCount();
}


void CVertexDictionary::SetRootVertexRange( int start, int end )
{
	m_nRootLODStart = start;
	m_nRootLODEnd   = end;
}

	
//-----------------------------------------------------------------------------
// Adds a vertex to the dictionary
//-----------------------------------------------------------------------------
int CVertexDictionary::AddVertex( const VertexInfo_t &srcVertex )
{
	int nDstVertID = m_Verts.AddToTail( srcVertex );
	VertexInfo_t &vertex = m_Verts[ nDstVertID ];
	ValidateBoneWeight( vertex.m_BoneWeight );
	SortBoneWeightByIndex( vertex.m_BoneWeight );
	ValidateBoneWeight( vertex.m_BoneWeight );

	return nDstVertID;
}


//-----------------------------------------------------------------------------
// Copies in a particular vertex from the s_source_t
//-----------------------------------------------------------------------------
int CVertexDictionary::AddVertexFromSource( const s_source_t *pSrc, int nVertexIndex )
{
	int nDstVertID = m_Verts.AddToTail( );
	VertexInfo_t &vertex = m_Verts[ nDstVertID ];

	vertex.m_Position   = pSrc->vertex[nVertexIndex].position;
	vertex.m_Normal     = pSrc->vertex[nVertexIndex].normal;
	vertex.m_TexCoord   = pSrc->vertex[nVertexIndex].texcoord;
	vertex.m_TangentS   = pSrc->vertex[nVertexIndex].tangentS;
	vertex.m_BoneWeight = pSrc->vertex[nVertexIndex].globalBoneweight;
	vertex.m_bLoD		= pSrc->vertex[nVertexIndex].bLoD;

	ValidateBoneWeight( vertex.m_BoneWeight );
	SortBoneWeightByIndex( vertex.m_BoneWeight );
	ValidateBoneWeight( vertex.m_BoneWeight );

	return nDstVertID;
}


//-----------------------------------------------------------------------------
// How many vertices in the dictionary?
//-----------------------------------------------------------------------------
int CVertexDictionary::VertexCount() const
{
	return m_Verts.Count();
}


s_source_t* GetModelLODSource( const char *pModelName, 
								const LodScriptData_t& scriptLOD, bool* pFound )
{
	// When doing LOD replacement, ignore all path + extension information
	char* pTempBuf = (char*)_alloca( strlen(pModelName) + 1 );

	// Strip off extensions for the source...
	strcpy( pTempBuf, pModelName ); 
	char* pDot = strrchr( pTempBuf, '.' );
	if (pDot)
		*pDot = 0;

	for( int i = 0; i < scriptLOD.modelReplacements.Size(); i++ )
	{
		// FIXME: Should we strip off path information?
//		char* pSlash = strrchr( pTempBuf1, '\\' );
//		char* pSlash2 = strrchr( pTempBuf1, '/' );
//		if (pSlash2 > pSlash)
//			pSlash = pSlash2;
//		if (!pSlash)
//			pSlash = pTempBuf1;

		if( !stricmp( pTempBuf, scriptLOD.modelReplacements[i].GetSrcName() ) )
		{
			*pFound = true;
			return scriptLOD.modelReplacements[i].m_pSource;
		}
	}

	*pFound = false;
	return 0;
}


//-----------------------------------------------------------------------------
// Tolerances for all fields of the vertex
//-----------------------------------------------------------------------------
#define POSITION_EPSILON	0.05f
#define TEXCOORD_EPSILON	0.1f
#define NORMAL_EPSILON		60.0f	// in degrees
#define TANGENT_EPSILON		60.0f	// in degrees
#define BONEWEIGHT_EPSILON	0.5f

#define UNMATCHED_BONE_WEIGHT 1.0f

//-----------------------------------------------------------------------------
// Computes error between two positions; returns false if the error is too great
//-----------------------------------------------------------------------------
bool ComparePositionFuzzy( const Vector &p1, const Vector &p2, float &flError )
{
	Vector vecDelta;
	VectorSubtract( p1, p2, vecDelta );
	flError = DotProduct( vecDelta, vecDelta );
	return ( flError <= (POSITION_EPSILON * POSITION_EPSILON) );
}


//-----------------------------------------------------------------------------
// Computes error between two normals; returns false if the error is too great
//-----------------------------------------------------------------------------
bool CompareNormalFuzzy( const Vector &n1, const Vector &n2, float &flError )
{ 
	static float flEpsilon = cos( DEG2RAD( NORMAL_EPSILON ) );

	Vector v1, v2;
	v1 = n1;
	v2 = n2;
	VectorNormalize( v1 );
	VectorNormalize( v2 );
	float flDot = DotProduct( v1, v2 );
	flError = 1.0F - flDot;
	return ( flDot >= flEpsilon );
}

//-----------------------------------------------------------------------------
// Computes error between two tangentS vectors; returns false if the error is too great
//-----------------------------------------------------------------------------
bool CompareTangentSFuzzy( const Vector4D &n1, const Vector4D &n2, float &flError )
{ 
	static float flEpsilon = cos( DEG2RAD( TANGENT_EPSILON ) );

	Vector4D v1, v2;
	v1 = n1;
	v2 = n2;

	if (v1.w != v2.w)
	{
		// must match as -1 or 1
		flError = 2;
		return false;
	}

	VectorNormalize( v1.AsVector3D() );
	VectorNormalize( v2.AsVector3D() );
	float flDot = DotProduct( v1.AsVector3D(), v2.AsVector3D() );

	// error ranges from [0..2]
	flError = 1.0F - flDot;

	return ( flDot >= flEpsilon );
}

//-----------------------------------------------------------------------------
// Computes error between two texcoords; returns false if the error is too great
//-----------------------------------------------------------------------------
bool CompareTexCoordsFuzzy( const Vector2D &t1, const Vector2D &t2, float &flError )
{
	Vector2D vecError;
	vecError[0] = fabs( t2[0] - t1[0] );
	vecError[1] = fabs( t2[1] - t1[1] );
	flError = vecError.LengthSqr();
	return ( flError <= (TEXCOORD_EPSILON * TEXCOORD_EPSILON) );
}


//-----------------------------------------------------------------------------
// Computes the error between two bone weights, returns false if they are too far
//-----------------------------------------------------------------------------
bool CompareBoneWeightsFuzzy( const s_boneweight_t &b1, const s_boneweight_t &b2, float &flError )
{
	// This is a list of which bones that exist in b1 also exist in b2.
	// Use the index to figure out where in the array for b2 that the corresponding bone in b1 is.
	int nMatchingBones = 0;
	int pBoneIndexMap1[MAX_NUM_BONES_PER_VERT]; 
	int pBoneIndexMap2[MAX_NUM_BONES_PER_VERT]; 

	int i;
	for ( i = 0; i < b2.numbones; ++i )
	{
		pBoneIndexMap2[i] = -1;
	}

	for ( i = 0; i < b1.numbones; ++i )
	{
		pBoneIndexMap1[i] = -1;
		for ( int j = 0; j < b2.numbones; ++j )
		{
			if ( b2.bone[j] == b1.bone[i] )
			{
				pBoneIndexMap1[i] = j;
				pBoneIndexMap2[j] = i;
				++nMatchingBones;
				break;
			}
		}
	}

	// If no bones match, we're done
	if ( !nMatchingBones )
	{
		flError = FLT_MAX;
		return false;
	}

	// At least one bone matches, so we're going to consider this vertex as a potential match
	// This loop will take care of figuring out the error for all bones that exist in
	// b1 alone, and all bones that exist in b1 and b2
	flError = 0;
	for ( i = 0; i < b1.numbones; ++i )
	{
		// If we didn't find a match for this bone, compute a more expensive weight
		if ( pBoneIndexMap1[i] == -1 )
		{
			flError += b1.weight[i] * b1.weight[i] * UNMATCHED_BONE_WEIGHT;
			continue;
		}

		float flDeltaWeight = fabs( b1.weight[i] - b2.weight[ pBoneIndexMap1[i] ] );
		flError += flDeltaWeight * flDeltaWeight;
	}

	// This loop will take care of figuring out the error for all bones that exist in b2 alone
	for ( i = 0; i < b2.numbones; ++i )
	{
		// If we didn't find a match for this bone, compute a more expensive weight
		if ( pBoneIndexMap2[i] == -1 )
		{
			flError += b2.weight[i] * b2.weight[i] * UNMATCHED_BONE_WEIGHT;
		}
	}

	// This renormalizes the error. The error will become greater with the total
	// number of bones in the two vertices.
	flError /= sqrt( (float) (b1.numbones + b2.numbones));
	return ( flError <= BONEWEIGHT_EPSILON );
}


//-----------------------------------------------------------------------------
// Searches for a material in the texture list
//-----------------------------------------------------------------------------
int FindMaterialByName( const char *pMaterialName )
{
	int i;
	int allocLen = strlen( pMaterialName ) + 1;
	char *pBaseName = ( char * )_alloca( allocLen );
	Q_FileBase( ( char * )pMaterialName, pBaseName, allocLen );

	for( i = 0; i < g_numtextures; i++ )
	{
		if( stricmp( pBaseName, g_texture[i].name ) == 0 )
		{
			return i;
		}
	}
	return -1;
}

static void GetLODSources( CUtlVector<s_source_t *> &lods, const s_model_t *pSrcModel )
{
	int lodID;
	int numLODs;

 	numLODs = g_ScriptLODs.Size();

	for( lodID = 0; lodID < numLODs; lodID++ )
	{
		LodScriptData_t& scriptLOD = g_ScriptLODs[lodID];

		bool found;
		s_source_t* pSource = GetModelLODSource( pSrcModel->filename, scriptLOD, &found );
		if (!pSource && !found)
		{
			pSource = pSrcModel->source;
		}

		lods[lodID] = pSource;
	}
}

static s_mesh_t *FindMeshByMaterial( s_source_t *pSrc, int nMaterialID )
{
	int m;
	for ( m = 0; m < pSrc->nummeshes; m++ )
	{
		if ( pSrc->meshindex[m] == nMaterialID )
		{
			return &pSrc->mesh[pSrc->meshindex[m]];
		}
	}
	
	// this mesh/material doesn't exist at this lod.
	return NULL;
}


static s_mesh_t *FindOrCullMesh( int nLodID, s_source_t *pSrc, int nMaterialID )
{
	char	baseMeshName[MAX_PATH];
	char	baseRemovalName[MAX_PATH];

	// possibly marked for removal via $removemesh
	// determine mesh name
	int nTextureID = material_to_texture( nMaterialID );
	if (nTextureID == -1)
	{
		MdlError( "Unknown Texture for Material %d\n", nMaterialID );
	}

	Q_FileBase(g_texture[nTextureID].name, baseMeshName, sizeof(baseMeshName)-1);
	for ( int i = 0; i < g_ScriptLODs[nLodID].meshRemovals.Count(); i++ )
	{
		const char *pMeshRemovalName = g_ScriptLODs[nLodID].meshRemovals[i].GetSrcName();
		Q_FileBase( pMeshRemovalName, baseRemovalName, sizeof(baseRemovalName)-1);

		if (!stricmp( baseRemovalName, baseMeshName ))
		{
			// mesh has been marked for removal
			return NULL;
		}
	}

	s_mesh_t *pMesh = FindMeshByMaterial( pSrc, nMaterialID );
	return pMesh;
}


//-----------------------------------------------------------------------------
// Makes sure all boneweights in a s_boneweight_t are valid
//-----------------------------------------------------------------------------
static void ValidateBoneWeight( const s_boneweight_t &boneWeight )
{
#ifdef _DEBUG
	int i;
	if( boneWeight.weight[0] == 1.0f )
	{
		Assert( boneWeight.numbones == 1 );
	}
	for( i = 0; i < boneWeight.numbones; i++ )
	{
		Assert( boneWeight.bone[i] >= 0 && boneWeight.bone[i] < g_numbones );
	}

	float weight = 0.0f;
	for( i = 0; i < boneWeight.numbones; i++ )
	{
		weight += boneWeight.weight[i] ;
	}
	Assert( fabs( weight - 1.0f ) < 1e-3 );
#endif
}


//-----------------------------------------------------------------------------
// Makes sure all boneweights in a source are valid
//-----------------------------------------------------------------------------
void ValidateBoneWeights( const s_source_t *pSrc )
{
	int i;
	for( i = 0; i < pSrc->numvertices; i++ )
	{
		Vector &pos = pSrc->vertex[i].position;
		Vector &norm = pSrc->vertex[i].normal;
		Vector2D &texcoord = pSrc->vertex[i].texcoord;
		s_boneweight_t *pBoneWeight = &pSrc->vertex[i].globalBoneweight;
		int j;
		for( j = 0; j < pBoneWeight->numbones; j++ )
		{
			int globalBoneID;
			globalBoneID = pBoneWeight->bone[j];
			const char *pBoneName = g_bonetable[globalBoneID].name;
			ValidateBoneWeight( *pBoneWeight );
		}
	}
}


static void CopyVerts( int nLodID, const s_source_t *pSrc, const s_mesh_t *pSrcMesh, CVertexDictionary &vertexDict, s_mesh_t *pDstMesh, int *pMeshVertIndexMap )
{
	// populate the dictionary with the verts
	for( int srcVertID = 0; srcVertID < pSrcMesh->numvertices; srcVertID++ )
	{
		int nVertexIndex = pSrcMesh->vertexoffset + srcVertID;
		pMeshVertIndexMap[ nVertexIndex ] = vertexDict.AddVertexFromSource( pSrc, nVertexIndex ) - pDstMesh->vertexoffset;
	}

	pDstMesh->numvertices = pSrcMesh->numvertices;
}

static void CopyFaces( const s_source_t *pSrc, const s_mesh_t *pSrcMesh, CUtlVector<s_face_t> &faces, s_mesh_t *pDstMesh )
{
	int srcFaceID;
	for( srcFaceID = 0; srcFaceID < pSrcMesh->numfaces; srcFaceID++ )
	{
		int srcID = srcFaceID + pSrcMesh->faceoffset;
		s_face_t *pSrcFace = &pSrc->face[srcID];
		s_face_t *pDstFace = &faces[faces.AddToTail()];
		pDstFace->a = pSrcFace->a;
		pDstFace->b = pSrcFace->b;
		pDstFace->c = pSrcFace->c;
		pDstMesh->numfaces++;
	}
}

#define IGNORE_POSITION		0x01
#define IGNORE_TEXCOORD		0x02
#define IGNORE_BONEWEIGHT	0x04
#define IGNORE_NORMAL		0x08
#define IGNORE_TANGENTS		0x10

//-----------------------------------------------------------------------------
// return -1 if there is no match. The index returned is used to index into vertexDict.
//-----------------------------------------------------------------------------
static int FindVertexWithinVertexDictionary( const VertexInfo_t &find, 
	const CVertexDictionary &vertexDict, int nStartVert, int nEndVert, int fIgnore )
{
	int		nBestIndex = -1;
	float	flPositionError;
	float	flNormalError;
	float	flTangentSError;
	float	flTexcoordError;
	float	flBoneWeightError;
	float	flMinPositionError = FLT_MAX;
	float	flMinNormalError = FLT_MAX;
	float	flMinTangentSError = FLT_MAX;
	float	flMinTexcoordError = FLT_MAX;
	float	flMinBoneWeightError = FLT_MAX;
	bool	bFound;

	if (fIgnore & IGNORE_POSITION)
	{
		flMinPositionError = 0;
		flPositionError    = 0;
	}

	if (fIgnore & IGNORE_TEXCOORD)
	{
		flMinTexcoordError = 0;
		flTexcoordError    = 0;
	}

	if (fIgnore & IGNORE_BONEWEIGHT)
	{
		flMinBoneWeightError = 0;
		flBoneWeightError    = 0;
	}

	if (fIgnore & IGNORE_NORMAL)
	{
		flMinNormalError = 0;
		flNormalError    = 0;
	}

	if (fIgnore & IGNORE_TANGENTS)
	{
		flMinTangentSError = 0;
		flTangentSError    = 0;
	}

	for ( int nVertexIndex = nStartVert; nVertexIndex < nEndVert; ++nVertexIndex )
	{
		// see if the position is reasonable
		if ( !(fIgnore & IGNORE_POSITION) && !ComparePositionFuzzy( find.m_Position, vertexDict.Vertex(nVertexIndex).m_Position, flPositionError ) )
			continue;

		if ( !(fIgnore & IGNORE_TEXCOORD) && !CompareTexCoordsFuzzy( find.m_TexCoord, vertexDict.Vertex(nVertexIndex).m_TexCoord, flTexcoordError ) )
			continue;

		if ( !(fIgnore & IGNORE_BONEWEIGHT) && !CompareBoneWeightsFuzzy( find.m_BoneWeight, vertexDict.Vertex(nVertexIndex).m_BoneWeight, flBoneWeightError ) )
			continue;

		if ( !(fIgnore & IGNORE_NORMAL) && !CompareNormalFuzzy( find.m_Normal, vertexDict.Vertex(nVertexIndex).m_Normal, flNormalError ) )
			continue;

		if ( !(fIgnore & IGNORE_TANGENTS) && !CompareTangentSFuzzy( find.m_TangentS, vertexDict.Vertex(nVertexIndex).m_TangentS, flTangentSError ) )
			continue;

		// the vert with minimum error is the best or exact candidate
		bFound = false;
		if (flMinPositionError > flPositionError)
		{
			bFound = true;
		}
		else if (flMinPositionError == flPositionError)
		{
			if (flMinTexcoordError > flTexcoordError)
			{
				bFound = true;
			}
			else if (flMinTexcoordError == flTexcoordError)
			{
				if (flMinBoneWeightError > flBoneWeightError)
				{
					bFound = true;
				}
				else if (flMinBoneWeightError == flBoneWeightError)
				{
					if (flMinNormalError > flNormalError)
					{
						bFound = true;
					}
					else if (flMinNormalError == flNormalError)
					{
						if (flMinTangentSError >= flTangentSError)
						{
							bFound = true;	
						}
					}
				}
			}
		}

		if (!bFound)
			continue;

		flMinPositionError	 = flPositionError;
		flMinTexcoordError	 = flTexcoordError;
		flMinBoneWeightError = flBoneWeightError;
		flMinNormalError	 = flNormalError;
		flMinTangentSError	 = flTangentSError;
		nBestIndex			 = nVertexIndex;
	}

	return nBestIndex;
}


//-----------------------------------------------------------------------------
// Use position, normal, and texcoord checks across the entire model to find a boneweight
//-----------------------------------------------------------------------------
static void FindBoneWeightWithinModel( const VertexInfo_t &searchVertex, const s_source_t *pSrc, s_boneweight_t &boneWeight, int fIgnore )
{
	int		nBestIndex = -1;
	float	flPositionError;
	float	flNormalError;
	float	flTangentSError;
	float	flTexcoordError;
	float	flMinPositionError = FLT_MAX;
	float	flMinNormalError = FLT_MAX;
	float	flMinTangentSError = FLT_MAX;
	float	flMinTexcoordError = FLT_MAX;
	bool	bFound;

	if (fIgnore & IGNORE_NORMAL)
	{
		flMinNormalError = 0;
		flNormalError    = 0;
	}

	if (fIgnore & IGNORE_TEXCOORD)
	{
		flMinTexcoordError = 0;
		flTexcoordError    = 0;
	}

	if (fIgnore & IGNORE_TANGENTS)
	{
		flMinTangentSError = 0;
		flTangentSError    = 0;
	}

	for ( int i = 0; i < pSrc->numvertices; i++ )
	{
		// Compute error metrics
		ComparePositionFuzzy( searchVertex.m_Position, pSrc->vertex[i].position, flPositionError );

		if (!(fIgnore & IGNORE_NORMAL))
		{
			CompareNormalFuzzy( searchVertex.m_Normal, pSrc->vertex[i].normal, flNormalError );
		}

		if (!(fIgnore & IGNORE_TEXCOORD))
		{
			CompareTexCoordsFuzzy( searchVertex.m_TexCoord, pSrc->vertex[i].texcoord, flTexcoordError );
		}

		if (!(fIgnore & IGNORE_TANGENTS))
		{
			CompareTangentSFuzzy( searchVertex.m_TangentS, pSrc->vertex[i].tangentS, flTangentSError );
		}

		// the vert with minimum error is the best or exact candidate
		bFound = false;
		if (flMinPositionError > flPositionError)
		{
			bFound = true;
		}
		else if (flMinPositionError == flPositionError)
		{
			if (flMinTexcoordError > flTexcoordError)
			{
				bFound = true;
			}
			else if (flMinTexcoordError == flTexcoordError)
			{
				if (flMinNormalError > flNormalError)
				{
					bFound = true;
				}
				else if (flMinNormalError == flNormalError)
				{
					if (flMinTangentSError >= flTangentSError)
					{
						bFound = true;
					}
				}
			}
		}

		if (bFound)
		{
			flMinPositionError  = flPositionError;
			flMinTexcoordError  = flTexcoordError;
			flMinNormalError    = flNormalError;
			flMinTangentSError  = flTangentSError;
			nBestIndex          = i;
		}
	}
	
	if ( nBestIndex == -1 )
	{
		MdlError( "Encountered a mesh with no vertices!\n" );
	}

	memcpy( &boneWeight, &pSrc->vertex[ nBestIndex ].globalBoneweight, sizeof(s_boneweight_t) );
}


//-----------------------------------------------------------------------------
// Modify the bone weights in all of the vertices....
//-----------------------------------------------------------------------------
static void RemapBoneWeights( const CUtlVector<int> &boneMap, s_boneweight_t &boneWeight )
{
	for( int i = 0; i < boneWeight.numbones; i++ )
	{
		Assert( boneWeight.bone[i] >= 0 && boneWeight.bone[i] < boneMap.Count() );
		boneWeight.bone[i] = boneMap[ boneWeight.bone[i] ];
	}
}


//-----------------------------------------------------------------------------
// Swap bones
//-----------------------------------------------------------------------------
static inline void SwapBones( s_boneweight_t &boneWeight, int nBone1, int nBone2 )
{
	// swap
	int nTmpBone = boneWeight.bone[nBone1];
	float flTmpWeight = boneWeight.weight[nBone1];
	boneWeight.bone[nBone1] = boneWeight.bone[nBone2];
	boneWeight.weight[nBone1] = boneWeight.weight[nBone2];
	boneWeight.bone[nBone2] = nTmpBone;
	boneWeight.weight[nBone2] = flTmpWeight;
}


//-----------------------------------------------------------------------------
// Sort the bone weight structure to be sorted by bone weight
//-----------------------------------------------------------------------------
static void SortBoneWeightByWeight( s_boneweight_t &boneWeight )
{
	// bubble sort the bones by weight. . .put the largest weight first.
	for( int j = boneWeight.numbones; j > 1; j-- )
	{
		for( int k = 0; k < j - 1; k++ )
		{
			if( boneWeight.weight[k] >= boneWeight.weight[k+1] )
				continue;

			SwapBones( boneWeight, k, k+1 );
		}
	}
}


//-----------------------------------------------------------------------------
// Sort the bone weight structure to be sorted by bone index
//-----------------------------------------------------------------------------
static void SortBoneWeightByIndex( s_boneweight_t &boneWeight )
{
	// bubble sort the bones by index. . .put the smallest index first.
	for ( int j = boneWeight.numbones; j > 1; j-- )
	{
		for( int k = 0; k < j - 1; k++ )
		{
			if( boneWeight.bone[k] <= boneWeight.bone[k+1] )
				continue;

			SwapBones( boneWeight, k, k+1 );
		}
	}
}


//-----------------------------------------------------------------------------
// After the remapping, we may get multiple instances of the same bone
// which we want to collapse into a single bone
//-----------------------------------------------------------------------------
static void CollapseBoneWeights( s_boneweight_t &boneWeight )
{
	// We need the bones to be sorted by bone index for the loop right below
	SortBoneWeightByIndex( boneWeight );

	for( int i = 0; i < boneWeight.numbones-1; i++ )
	{
		if( boneWeight.bone[i] != boneWeight.bone[i+1] )
			continue;

		// add i+1's weight to i since they have the same bone index
		boneWeight.weight[i] += boneWeight.weight[i+1];

		// remove i+1
		for( int j = i+1; j < boneWeight.numbones-1; j++ )
		{
			boneWeight.bone[j] = boneWeight.bone[j+1];
			boneWeight.weight[j] = boneWeight.weight[j+1];
		}
		--boneWeight.numbones;

		// Gotta step back one, may have many bones collapsing into one
		--i;
	}

	ValidateBoneWeight( boneWeight );
}


//-----------------------------------------------------------------------------
// Find a matching vertex within the root lod 
//-----------------------------------------------------------------------------
static void CalculateBoneWeightFromRootLod( const VertexInfo_t &searchVertex, CVertexDictionary &vertexDict, 
	const s_source_t *pRootLODSrc, VertexInfo_t &idealVertex )
{
	idealVertex = searchVertex;

	// Look through the part of the vertex dictionary associated with the root LODs for a match
	// bone weights are not defined properly in SMDs for lower LODs, so don't consider
	// we can only accept the boneweight from the root LOD
	int nVertexDictID = FindVertexWithinVertexDictionary( searchVertex, vertexDict, 
		vertexDict.RootLODVertexStart(), vertexDict.RootLODVertexEnd(), IGNORE_BONEWEIGHT|IGNORE_TANGENTS ); 
	if ( nVertexDictID != -1 )
	{
		Assert( nVertexDictID >= vertexDict.RootLODVertexStart() && nVertexDictID < vertexDict.RootLODVertexEnd() );
		Assert( nVertexDictID >= 0 && nVertexDictID < vertexDict.VertexCount() );

		// found vertex in dictionary
#ifdef UNIQUE_VERTEXES_FOR_LOD
		// keep entry vertex and fill in the missing bone weight attribute
		idealVertex.m_BoneWeight = vertexDict.Vertex( nVertexDictID ).m_BoneWeight;
#else
		// discard entry vertex in favor of best match
		// this ensures all the attributes, including bone weight are correct for that vertex
		// the worst case is that the vertex is not an *exact* match for entry attributes just a "close" match
		idealVertex = vertexDict.Vertex( nVertexDictID );
#endif
		return;
	}

	// In this case, we didn't find anything within the tolerance, so we need to
	// do a *positional check only* to give us a bone weight to assign to this vertex.
	FindBoneWeightWithinModel( searchVertex, pRootLODSrc, idealVertex.m_BoneWeight, IGNORE_BONEWEIGHT|IGNORE_TANGENTS );
}

//-----------------------------------------------------------------------------
// Find a matching vertex
//-----------------------------------------------------------------------------
static void CalculateIdealVert( const VertexInfo_t &searchVertex, CVertexDictionary &vertexDict, 
	const s_mesh_t *pVertexDictMesh, const s_source_t *pRootLODSrc, VertexInfo_t &idealVertex )
{
#ifndef UNIQUE_VERTEXES_FOR_LOD
	// Only look through the part of the vertex dictionary associated with all *higher* LODs for a match
	int nVertexDictID = FindVertexWithinVertexDictionary( searchVertex, vertexDict, 
		pVertexDictMesh->vertexoffset, vertexDict.PrevLODVertexCount(), 0 ); 
	if ( nVertexDictID != -1 )
	{
		Assert( nVertexDictID >= pVertexDictMesh->vertexoffset && nVertexDictID < vertexDict.PrevLODVertexCount() );
		Assert( nVertexDictID >= 0 && nVertexDictID < vertexDict.VertexCount() );

		// found vertex in dictionary
		idealVertex = vertexDict.Vertex( nVertexDictID );
		return;
	}
#endif

	// could not find a tolerant match
	// the search vertex is unique
	idealVertex = searchVertex;
}


static bool FuzzyFloatCompare( float f1, float f2, float epsilon )
{
	if( fabs( f1 - f2 ) < epsilon )
	{
		return true;
	}
	else
	{
		return false;
	}
}
								

//-----------------------------------------------------------------------------
// Is this bone weight structure sorted by bone?
//-----------------------------------------------------------------------------
static bool IsBoneWeightSortedByBone( const s_boneweight_t &src )
{
	int nLastBone = -1;
	for ( int i = 1; i < src.numbones; ++i )
	{
		Assert( src.bone[i] != -1 );
		if ( src.bone[ i-1 ] > src.bone[ i ] )
			return false;
	}

	return true;
}

	
//-----------------------------------------------------------------------------
// Are two bone-weight structures equal?
//-----------------------------------------------------------------------------
static bool AreBoneWeightsEqual( const s_boneweight_t &b1, const s_boneweight_t &b2 )
{
	// Have to have the same number of bones
	if ( b1.numbones != b2.numbones )
		return false;

	// This is a list of which bones that exist in b1 also exist in b2.
	// Use the index to figure out where in the array for b2 that the corresponding bone in b1 is.
	int nMatchingBones = 0;
	int pBoneIndexMap[MAX_NUM_BONES_PER_VERT]; 

	int i;
	for ( i = 0; i < b1.numbones; ++i )
	{
		pBoneIndexMap[i] = -1;
		for ( int j = 0; j < b2.numbones; ++j )
		{
			if ( b2.bone[j] == b1.bone[i] )
			{
				pBoneIndexMap[i] = j;
				++nMatchingBones;
				break;
			}
		}
	}

	// If we aren't using the same bone indices, we're done
	if ( nMatchingBones != b1.numbones )
		return false;

	// Check to see if the weights are the same
	for ( i = 0; i < b1.numbones; ++i )
	{
		Assert( pBoneIndexMap[i] != -1 );
		if ( b1.weight[i] != b2.weight[ pBoneIndexMap[i] ] )
			return false;
	}

	return true;
}


//-----------------------------------------------------------------------------
// Finds an *exact* requested vertex in the dictionary
//-----------------------------------------------------------------------------
static int FindVertexInDictionaryExact( CVertexDictionary &vertexDict, int nStartVert, int nEndVert, const VertexInfo_t &vertex )
{
	for ( int nVertID = nStartVert; nVertID < nEndVert; ++nVertID )
	{
		if ( vertexDict.Vertex( nVertID ).m_Position != vertex.m_Position )
			continue;

		if ( !AreBoneWeightsEqual( vertexDict.Vertex( nVertID ).m_BoneWeight, vertex.m_BoneWeight ) )
			continue;

		if ( vertexDict.Vertex( nVertID ).m_TexCoord != vertex.m_TexCoord )
			continue;

		if ( vertexDict.Vertex( nVertID ).m_Normal != vertex.m_Normal )
			continue;

		if ( vertexDict.Vertex( nVertID ).m_TangentS != vertex.m_TangentS )
			continue;

		return nVertID;
	}

	return -1;
}


//-----------------------------------------------------------------------------
// Finds the *exact* requested vertex in the dictionary or creates it
//-----------------------------------------------------------------------------
static int FindOrCreateExactVertexInDictionary( CVertexDictionary &vertexDict, 
	const VertexInfo_t &vertex, s_mesh_t *pDstMesh )
{
	int nMeshVertID = FindVertexInDictionaryExact( vertexDict, pDstMesh->vertexoffset, pDstMesh->vertexoffset+pDstMesh->numvertices, vertex );
	if ( nMeshVertID != -1 )
	{
		// flag vertex for what LoD's are using it
		vertexDict.Vertex( nMeshVertID ).m_bLoD |= vertex.m_bLoD;
		return nMeshVertID - pDstMesh->vertexoffset;
	}

	nMeshVertID = vertexDict.AddVertex( vertex );
	++pDstMesh->numvertices;
	return nMeshVertID - pDstMesh->vertexoffset;
}

static void PrintBonesUsedInLOD( s_source_t *pSrc )
{
	printf( "PrintBonesUsedInLOD\n" );
	int i;
	for( i = 0; i < pSrc->numvertices; i++ )
	{
		Vector &pos = pSrc->vertex[i].position;
		Vector &norm = pSrc->vertex[i].normal;
		Vector2D &texcoord = pSrc->vertex[i].texcoord;
		printf( "pos: %f %f %f norm: %f %f %f texcoord: %f %f\n",
			pos[0], pos[1], pos[2], norm[0], norm[1], norm[2], texcoord[0], texcoord[1] );
		s_boneweight_t *pBoneWeight = &pSrc->vertex[i].globalBoneweight;
		int j;
		for( j = 0; j < pBoneWeight->numbones; j++ )
		{
			int globalBoneID = pBoneWeight->bone[j];
			const char *pBoneName = g_bonetable[globalBoneID].name;
			printf( "vert: %d bone: %d boneid: %d weight: %f name: \"%s\"\n", i, ( int )j, ( int )pBoneWeight->bone[j], 
				( float )pBoneWeight->weight[j], pBoneName );
		}
		printf( "\n" );
		fflush( stdout );
	}
}


//-----------------------------------------------------------------------------
// Indicates a particular set of bones is used by a particular LOD
//-----------------------------------------------------------------------------
static void	MarkBonesUsedByLod( const s_boneweight_t &boneWeight, int nLodID )
{
	for( int j = 0; j < boneWeight.numbones; ++j )
	{
		int nGlobalBoneID = boneWeight.bone[j];
		s_bonetable_t *pBone = &g_bonetable[nGlobalBoneID];
		pBone->flags |= ( BONE_USED_BY_VERTEX_LOD0 << nLodID );
	}
}


static void PrintSBoneWeight( s_boneweight_t *pBoneWeight, const s_source_t *pSrc )
{
	int j;
	for( j = 0; j < pBoneWeight->numbones; j++ )
	{
		int globalBoneID;
		globalBoneID = pBoneWeight->bone[j];
		const char *pBoneName = g_bonetable[globalBoneID].name;
		printf( "bone: %d boneid: %d weight: %f name: \"%s\"\n", ( int )j, ( int )pBoneWeight->bone[j], 
			( float )pBoneWeight->weight[j], pBoneName );
	}
}



//-----------------------------------------------------------------------------
// In the non-top LOD, look for vertices that would be appropriate from the
// vertex dictionary, and use them if you find them, or add new vertices to the 
// vertex dictionary if not and use those new vertices.
//-----------------------------------------------------------------------------
static void CreateLODVertsInDictionary( int nLodID, const s_source_t *pRootLODSrc, s_source_t *pCurrentLODSrc, 
	const s_mesh_t *pCurrLODMesh, s_mesh_t *pVertexDictMesh, CVertexDictionary &vertexDict, int *pMeshVertIndexMap )
{
	// this function is specific to lods and not the root
	Assert( nLodID );

	int nNumCurrentVerts = vertexDict.VertexCount();

	// Used to control where we look for vertices + merging rules
	vertexDict.StartNewLOD();

	CUtlVector<int> boneMap;
	BuildBoneLODMapping( boneMap, nLodID );

	for( int nSrcVertID = 0; nSrcVertID < pCurrLODMesh->numvertices; ++nSrcVertID )
	{
		int nSrcID = nSrcVertID + pCurrLODMesh->vertexoffset;

		// candidate vertex
		// vertices at lower LODs have bogus boneweights assigned
		// must get the boneweight from the nearest or exact vertex at root lod
		VertexInfo_t vertex;
		vertex.m_Position   = pCurrentLODSrc->vertex[nSrcID].position; 
		vertex.m_Normal     = pCurrentLODSrc->vertex[nSrcID].normal;
		vertex.m_TexCoord   = pCurrentLODSrc->vertex[nSrcID].texcoord;
		vertex.m_TangentS   = pCurrentLODSrc->vertex[nSrcID].tangentS;

#ifdef _DEBUG
		memset( &vertex.m_BoneWeight, 0xDD, sizeof( s_boneweight_t ) );
#endif
		// determine the best bone weight for the desired vertex within the root lod only
		// the root lod contains no bone remappings
		// this ensures we get a vertex with its matched proper boneweight assignment
		VertexInfo_t idealVertex;
		CalculateBoneWeightFromRootLod( vertex, vertexDict, pRootLODSrc, idealVertex );

		// try again to match the candidate vertex
		// determine the ideal vertex with desired remapped boneweight
		vertex = idealVertex;
		CalculateIdealVert( vertex, vertexDict, pVertexDictMesh, pRootLODSrc, idealVertex);

		// remap bone
		RemapBoneWeights( boneMap, idealVertex.m_BoneWeight );
		CollapseBoneWeights( idealVertex.m_BoneWeight );
		SortBoneWeightByWeight( idealVertex.m_BoneWeight );

		// FIXME: this is marking bones based on the slammed vertex data
		MarkBonesUsedByLod( idealVertex.m_BoneWeight, nLodID );

		// tag ideal vertex as being part of the current lod
		idealVertex.m_bLoD		= 1 << nLodID;

		// Find the exact vertex or create it in the dictionary
		int nMeshVertID = FindOrCreateExactVertexInDictionary( vertexDict, idealVertex, pVertexDictMesh );

		// Indicate where in the higher LODs the vertex we selected resides
		pMeshVertIndexMap[nSrcID] = nMeshVertID;
	}

	int nNewVertsCreated = vertexDict.VertexCount() - nNumCurrentVerts;
	if (!g_quiet && nNewVertsCreated)
	{
		printf( "Lod %d: vertexes: %d (%d new)\n", nLodID, vertexDict.VertexCount(), nNewVertsCreated);
	}
}

static void PrintSourceVerts( s_source_t *pSrc )
{
	int i;
	for( i = 0; i < pSrc->numvertices; i++ )
	{
		printf( "v %d ", i );
		printf( "pos: %f %f %f ", pSrc->vertex[i].position[0], pSrc->vertex[i].position[1], pSrc->vertex[i].position[2] );
		printf( "norm: %f %f %f ", pSrc->vertex[i].normal[0], pSrc->vertex[i].normal[1], pSrc->vertex[i].normal[2] );
		printf( "texcoord: %f %f\n", pSrc->vertex[i].texcoord[0], pSrc->vertex[i].texcoord[1] );
		int j;
		for( j = 0; j < pSrc->vertex[i].globalBoneweight.numbones; j++ )
		{
			printf( "\t%d: %d %f\n", j, ( int )pSrc->vertex[i].globalBoneweight.bone[j], 
				pSrc->vertex[i].globalBoneweight.weight[j] );
		}
		fflush( stdout );
	}
}


//-----------------------------------------------------------------------------
// Copy the vertex dictionary to the finalized processed data
// Leaves the source data intact, necessary for later processes.
// Routines can then choose which data they operate on
//-----------------------------------------------------------------------------
static void SetProcessedWithDictionary( CUtlVector<s_source_t*> &lods, CVertexDictionary &vertexDict,
	CUtlVector<s_face_t> &faces, CUtlVector<s_mesh_t> &meshes, int *pMeshVertIndexMaps[MAX_NUM_LODS] )
{
	int	i;
	int nNumLODs = lods.Count();
	s_source_t *pRootLodSrc = lods[0];

	s_loddata_t *pLodData = new s_loddata_t;
	memset(pLodData, 0, sizeof(s_loddata_t));
	
	// all lods have link to processed data
	for (i=0; i<nNumLODs; i++)
	{
		lods[i]->pLodData = pLodData;
	}

	int nVertexCount = vertexDict.VertexCount();

	pLodData->vertex = (s_vertexinfo_t *)kalloc( nVertexCount, sizeof( s_vertexinfo_t ) );
	pLodData->numvertices = nVertexCount;
	pLodData->face = (s_face_t *)kalloc( faces.Count(), sizeof( s_face_t ));
	pLodData->numfaces = faces.Count();
	
	for ( i = 0; i < nVertexCount; ++i )
	{
		pLodData->vertex[i].globalBoneweight = vertexDict.Vertex( i ).m_BoneWeight;
		Assert( pLodData->vertex[i].globalBoneweight.numbones <= 4 );
		pLodData->vertex[i].position	= vertexDict.Vertex( i ).m_Position;
		pLodData->vertex[i].normal		= vertexDict.Vertex( i ).m_Normal;
		pLodData->vertex[i].texcoord	= vertexDict.Vertex( i ).m_TexCoord;
		pLodData->vertex[i].tangentS	= vertexDict.Vertex( i ).m_TangentS;
		pLodData->vertex[i].bLoD		= vertexDict.Vertex( i ).m_bLoD;
	}

	memcpy( pLodData->face, faces.Base(), faces.Count() * sizeof( s_face_t ) );
	memcpy( pLodData->mesh, meshes.Base(), meshes.Count() * sizeof( s_mesh_t ) );

	for (i=0; i<MAX_NUM_LODS; i++)
	{
		pLodData->pMeshVertIndexMaps[i] = pMeshVertIndexMaps[i];
	}
}


//-----------------------------------------------------------------------------
// This fills out boneMap, which is a mapping from src bone to src bone replacement (or to itself
// if there is no bone replacement.
//-----------------------------------------------------------------------------
static void BuildBoneLODMapping( CUtlVector<int> &boneMap, int lodID )
{
	boneMap.AddMultipleToTail( g_numbones );

	Assert( lodID < g_ScriptLODs.Size() );
	LodScriptData_t& scriptLOD = g_ScriptLODs[lodID];

	// First, create a direct mapping where no bones are collapsed
	int i;
	for( i = 0; i < g_numbones; i++ )
	{
		boneMap[i] = i;
	}

	for( i = 0; i < scriptLOD.boneReplacements.Size(); i++ )
	{
		const char *src, *dst;
		src = scriptLOD.boneReplacements[i].GetSrcName();
		dst = scriptLOD.boneReplacements[i].GetDstName();
		int j = findGlobalBone( src );
		int k = findGlobalBone( dst );

		if ( j != -1 && k != -1)
		{
			boneMap[j] = k;
		}
		else if ( j == -1)
		{
			// FIXME: is this really an error?  It could just be  replacement command for bone that doesnt' exist anymore.
			if (g_verbose)
			{
				MdlWarning( "Couldn't replace unknown bone \"%s\" with \"%s\"\n", src, dst );
			}
		}
		else
		{
			// FIXME: is this really an error?  It could just be  replacement command for bone that doesnt' exist anymore.
			if (g_verbose)
			{
				MdlWarning( "Couldn't replace bone \"%s\" with unknown \"%s\"\n", src, dst );
			}
		}
	}
}

static void MarkRootLODBones( CVertexDictionary &vertexDictionary )
{
	// should result in an identity mapping
	// because their are no bone remaps at the root lod
	CUtlVector<int> boneMap;
	BuildBoneLODMapping( boneMap, 0 );

	// iterate and mark bones
	for (int nVertDictID=vertexDictionary.RootLODVertexStart(); nVertDictID<vertexDictionary.RootLODVertexEnd(); nVertDictID++)
	{
		s_boneweight_t &boneWeight = vertexDictionary.Vertex( nVertDictID ).m_BoneWeight;

		RemapBoneWeights( boneMap, boneWeight );
		CollapseBoneWeights( boneWeight );
		SortBoneWeightByWeight( boneWeight );

		MarkBonesUsedByLod( boneWeight, 0 );
	}
}

//-----------------------------------------------------------------------------
// Computes LOD vertices for a model piece.
//-----------------------------------------------------------------------------
static void UnifyModelLODs( s_model_t *pSrcModel )
{
	CUtlVector<s_source_t *> lods;
	int nNumLODs = g_ScriptLODs.Count();
	lods.AddMultipleToTail( nNumLODs );
	
	if( Q_stricmp( pSrcModel->name, "blank" ) == 0 )
		return;
	
	// lod source are not gauranteed to be unique
	// an lod's source may be the same source at multiple lods
	// and therefore shared
	GetLODSources( lods, pSrcModel );
	
	// each lod has a unique vertex mapping table
	int nLodID;
	int *pMeshVertIndexMaps[MAX_NUM_LODS];
	for ( nLodID = 0; nLodID < MAX_NUM_LODS; nLodID++ )
	{
		if ( nLodID < nNumLODs && lods[nLodID] )
		{
			pMeshVertIndexMaps[nLodID] = new int[lods[nLodID]->numvertices];
#ifdef _DEBUG
			memset( pMeshVertIndexMaps[nLodID], 0xDD, lods[nLodID]->numvertices * sizeof(int) );
#endif
		}
		else
		{
			pMeshVertIndexMaps[nLodID] = NULL;
		}
	}

	// These hold the aggregate data for the model that grows as lods are processed
	CVertexDictionary vertexDictionary;
	CUtlVector<s_face_t> faces;
	CUtlVector<s_mesh_t> meshes;
	
	meshes.AddMultipleToTail( MAXSTUDIOSKINS );
	Assert( meshes.Count() == MAXSTUDIOSKINS );
	memset( meshes.Base(), 0, meshes.Count() * sizeof( s_mesh_t ) );

	int nMeshID;
	for( nMeshID = 0; nMeshID < pSrcModel->source->nummeshes; nMeshID++ )
	{
		s_mesh_t *pVertexDictMesh = &meshes[pSrcModel->source->meshindex[nMeshID]];
		
		pVertexDictMesh->numvertices = 0;
		pVertexDictMesh->vertexoffset = vertexDictionary.VertexCount();
		pVertexDictMesh->numfaces = 0;
		pVertexDictMesh->faceoffset = faces.Count();
		
		// First build up information for LOD 0
		if ( !lods[0] )
			continue;

		// lookup the material used by this mesh
		int nMaterialID = lods[0]->meshindex[nMeshID];
		s_mesh_t *pLOD0Mesh = FindMeshByMaterial( lods[0], nMaterialID );
		if ( !pLOD0Mesh )
			continue;

		// populate with all vertices from LOD 0
		int nStart = vertexDictionary.VertexCount();
		CopyVerts( 0, lods[0], pLOD0Mesh, vertexDictionary, pVertexDictMesh, pMeshVertIndexMaps[0] );
		vertexDictionary.SetRootVertexRange( nStart, vertexDictionary.VertexCount() );
	
		MarkRootLODBones( vertexDictionary );

		// only fix up the faces for the highest lod since the lowest ones are going
		// to be reprocessed later.
		CopyFaces( lods[0], pLOD0Mesh, faces, pVertexDictMesh );

		// Now, for each LOD, try to build meshes using the vertices in LOD 0.
		// Ideally, vertices used in an LOD would be in LOD 0 for the benefit of shared vertices.
		// If we don't find vertices in LOD 0, this code will add vertices into LOD 0's list
		// of vertices for the next LOD to find
		for ( nLodID = 1; nLodID < nNumLODs; ++nLodID )
		{
			s_source_t *pCurrLOD = lods[nLodID];
			if ( !pCurrLOD )
				continue;

			// Find the mesh that matches the material
			// mesh may not be present or could be culled due to $removemesh commands
			s_mesh_t *pCurrLODMesh = FindOrCullMesh( nLodID, pCurrLOD, nMaterialID );
			if ( !pCurrLODMesh )
				continue;

			CreateLODVertsInDictionary( nLodID, lods[0], pCurrLOD, pCurrLODMesh, pVertexDictMesh, vertexDictionary, pMeshVertIndexMaps[nLodID]);
		}
	}

#ifdef _DEBUG
	Msg( "Total vertex count: %d\n", vertexDictionary.VertexCount() );
#endif

	// save the data we just built into the processed data section
	// The processed data has all of the verts that are needed for all LODs.
	SetProcessedWithDictionary( lods, vertexDictionary, faces, meshes, pMeshVertIndexMaps );
//	PrintSourceVerts( lods[0] );
}

// Force the vertex array for a model to have all of the vertices that are needed
// for all of the LODs of the model.
void UnifyLODs( void )
{
	int modelID;

	// todo: need to fixup the firstref/lastref stuff . . do we really need it anymore?
	for( modelID = 0; modelID < g_nummodelsbeforeLOD; modelID++ )
	{
		UnifyModelLODs( g_model[modelID] );
	}
}

static int g_NumBonesInLOD[MAX_NUM_LODS];

static void PrintSpaces( int numSpaces )
{
	int i;
	for( i = 0; i < numSpaces; i++ )
	{
		printf( " " );
	}
}

static void SpewBoneInfo( int globalBoneID, int depth )
{
	s_bonetable_t *pBone = &g_bonetable[globalBoneID];
	if( g_bPrintBones )
	{
		PrintSpaces( depth * 2 );
		printf( "%d \"%s\" ", depth, pBone->name );
	}
	int i;
	for( i = 0; i < 8; i++ )
	{
		if( pBone->flags & ( BONE_USED_BY_VERTEX_LOD0 << i ) )
		{
			if( g_bPrintBones )
			{
				printf( "lod%d ", i );
			}
			g_NumBonesInLOD[i]++;
		}
	}
	if( g_bPrintBones )
	{
		printf( "\n" );	
	}
	
	int j;
	for( j = 0; j < g_numbones; j++ )
	{
		s_bonetable_t *pBone = &g_bonetable[j];
		if( pBone->parent == globalBoneID )
		{
			SpewBoneInfo( j, depth + 1 );
		}
	}
}

void SpewBoneUsageStats( void )
{
	memset( g_NumBonesInLOD, 0, sizeof( int ) * MAX_NUM_LODS );
	if( g_numbones == 0 )
	{
		return;
	}
	SpewBoneInfo( 0, 0 );
	if( g_bPrintBones )
	{
		int i;
		for( i = 0; i < g_ScriptLODs.Count(); i++ )
		{
			printf( "\t%d bones used in lod %d\n", g_NumBonesInLOD[i], i );
		}
	}
}

void MarkParentBoneLODs( void )
{
	int i;
	for( i = 0; i < g_numbones; i++ )
	{
		int flags = g_bonetable[i].flags;
		flags &= BONE_USED_BY_VERTEX_MASK;
		int globalBoneID = g_bonetable[i].parent;
		while( globalBoneID != -1 )
		{
			g_bonetable[globalBoneID].flags |= flags;
			globalBoneID = g_bonetable[globalBoneID].parent;
		}
	}
}

static void LoadModelLODSource( s_model_t *pSrcModel )
{
	CUtlVector<s_source_t *> lods;
	int numLODs = g_ScriptLODs.Size();
	lods.AddMultipleToTail( numLODs );
	
	if( stricmp( pSrcModel->name, "blank" ) == 0 )
	{
		return;
	}
	
	GetLODSources( lods, pSrcModel );
}

void LoadLODSources( void )
{
	g_nummodelsbeforeLOD = g_nummodels;
	for( int modelID = 0; modelID < g_nummodelsbeforeLOD; modelID++ )
	{
		LoadModelLODSource( g_model[modelID] );
	}
}

static void ReplaceBonesRecursive( int globalBoneID, bool replaceThis, 
								   CUtlVector<CLodScriptReplacement_t> &boneReplacements, 
								   const char *replacementName )
{
	if( replaceThis )
	{
		CLodScriptReplacement_t &boneReplacement = boneReplacements[boneReplacements.AddToTail()];
		boneReplacement.SetSrcName( g_bonetable[globalBoneID].name );
		boneReplacement.SetDstName( replacementName );
	}

	// find children and recurse.
	int i;
	for( i = 0; i < g_numbones; i++ )
	{
		if( g_bonetable[i].parent == globalBoneID )
		{
			ReplaceBonesRecursive( i, true, boneReplacements, replacementName );
		}
	}
}

static void ConvertSingleBoneTreeCollapseToReplaceBones( CLodScriptReplacement_t &boneTreeCollapse, 
														 CUtlVector<CLodScriptReplacement_t> &boneReplacements )
{
	// find the bone that we are starting with.
	int i = findGlobalBone( boneTreeCollapse.GetSrcName() );
	if (i != -1)
	{
		ReplaceBonesRecursive( i, false, boneReplacements, g_bonetable[i].name );
		return;
	}
	MdlWarning( "Couldn't find bone %s for bonetreecollapse, skipping\n", boneTreeCollapse.GetSrcName() );
}

void ConvertBoneTreeCollapsesToReplaceBones( void )
{
	int i;
	for( i = 0; i < g_ScriptLODs.Size(); i++ )
	{
		LodScriptData_t& lod = g_ScriptLODs[i];
		int j;
		for( j = 0; j < lod.boneTreeCollapses.Size(); j++ )
		{
			ConvertSingleBoneTreeCollapseToReplaceBones( lod.boneTreeCollapses[j], 
				lod.boneReplacements );
		}
	}
}

/*
static void PrintReplacedBones( LodScriptData_t &lod )
{
	int i;
	for( i = 0; i < lod.boneReplacements.Count(); i++ )
	{
		printf( "%s -> %s\n", 
			lod.boneReplacements[i].GetSrcName(), 
			lod.boneReplacements[i].GetDstName() );
	}
}
*/

void FixupReplacedBonesForLOD( LodScriptData_t &lod )
{
/*
	printf( "before:\n" );
	PrintReplacedBones( lod );
*/
	bool changed;
	int i;
	int j;
	do
	{
		changed = false;
		for( i = 0; i < lod.boneReplacements.Count(); i++ )
		{
			for( j = 0; j < lod.boneReplacements.Count(); j++ )
			{
				if( i == j )
				{
					continue;
				}
				if( Q_stricmp( lod.boneReplacements[i].GetSrcName(), lod.boneReplacements[j].GetDstName() ) == 0 )
				{
					lod.boneReplacements[j].SetDstName( lod.boneReplacements[i].GetDstName() );
					changed = true;
				}
			}
		}
	} while( changed );
/*
	printf( "after:\n" );
	PrintReplacedBones( lod );
*/
}

void FixupReplacedBones( void )
{
	int i;
	for( i = 0; i < g_ScriptLODs.Size(); i++ )
	{
		FixupReplacedBonesForLOD( g_ScriptLODs[i] );
	}
}