C++ NvFaceInfoVec类代码示例

///////////////////////////////////////////////////////////////////////////////////////////
// Combine()
//
// Combines the two input face vectors and puts the result into m_faces
//
void NvStripInfo::Combine(const NvFaceInfoVec &forward, const NvFaceInfoVec &backward){
	
	// add backward faces
	int numFaces = backward.size();
	for (int i = numFaces - 1; i >= 0; i--)
		m_faces.push_back(backward[i]);
	
	// add forward faces
	numFaces = forward.size();
	for (int i = 0; i < numFaces; i++)
		m_faces.push_back(forward[i]);
}

///////////////////////////////////////////////////////////////////////////////////////////
// FindStartPoint()
//
// Finds a good starting point, namely one which has only one neighbor
//
int NvStripifier::FindStartPoint(NvFaceInfoVec &faceInfos, NvEdgeInfoVec &edgeInfos)
{
	int bestCtr = -1;
	int bestIndex = -1;

	for(size_t i = 0; i < faceInfos.size(); i++)
	{
		int ctr = 0;
		
		if(FindOtherFace(edgeInfos, faceInfos[i]->m_v0, faceInfos[i]->m_v1, faceInfos[i]) == NULL)
			ctr++;
		if(FindOtherFace(edgeInfos, faceInfos[i]->m_v1, faceInfos[i]->m_v2, faceInfos[i]) == NULL)
			ctr++;
		if(FindOtherFace(edgeInfos, faceInfos[i]->m_v2, faceInfos[i]->m_v0, faceInfos[i]) == NULL)
			ctr++;
		if(ctr > bestCtr)
		{
			bestCtr = ctr;
			bestIndex = i;
			//return i;
		}
	}
	//return -1;
	
	if(bestCtr == 0)
		return -1;
	else
		return bestIndex;
}

////////////////////////////////////////////////////////////////////////////////////////
// RemoveSmallStrips()
//
// allStrips is the whole strip _vector_...all small strips will be deleted from this list, to avoid leaking mem
// allBigStrips is an out parameter which will contain all strips above minStripLength
// faceList is an out parameter which will contain all faces which were removed from the striplist
//
void NvStripifier::RemoveSmallStrips(NvStripInfoVec& allStrips, NvStripInfoVec& allBigStrips, NvFaceInfoVec& faceList)
{
	faceList.clear();
	allBigStrips.clear();  //make sure these are empty
	NvFaceInfoVec tempFaceList;
	
	for(int i = 0; i < allStrips.size(); i++)
	{
		if(allStrips[i]->m_faces.size() < minStripLength)
		{
			//strip is too small, add faces to faceList
			for(int j = 0; j < allStrips[i]->m_faces.size(); j++)
				tempFaceList.push_back(allStrips[i]->m_faces[j]);
			
			//and xr_free memory
			xr_delete(allStrips[i]);
		}
		else
		{
			allBigStrips.push_back(allStrips[i]);
		}
	}
	
	bool *bVisitedList	= xr_alloc<bool> (tempFaceList.size());
	ZeroMemory			(bVisitedList, tempFaceList.size()*sizeof(bool));
	
	VertexCache* vcache = xr_new<VertexCache> (cacheSize);
	
	int bestNumHits = -1;
	int numHits		= 0;
	int bestIndex	= 0;
	
	while(1)
	{
		bestNumHits = -1;
		
		//find best face to add next, given the current cache
		for(int i = 0; i < tempFaceList.size(); i++)
		{
			if(bVisitedList[i])
				continue;
			
			numHits = CalcNumHitsFace(vcache, tempFaceList[i]);
			if(numHits > bestNumHits)
			{
				bestNumHits = numHits;
				bestIndex = i;
			}
		}
		
		if(bestNumHits == -1.0f)
			break;
		bVisitedList[bestIndex] = true;
		UpdateCacheFace(vcache, tempFaceList[bestIndex]);
		faceList.push_back(tempFaceList[bestIndex]);
	}
	
	xr_delete	(vcache);
	xr_free		(bVisitedList);
}

bool NvStripifier::AlreadyExists(NvFaceInfo* faceInfo, NvFaceInfoVec& faceInfos)
{
	for(size_t i = 0; i < faceInfos.size(); ++i)
	{
		if( (faceInfos[i]->m_v0 == faceInfo->m_v0) &&
			(faceInfos[i]->m_v1 == faceInfo->m_v1) &&
			(faceInfos[i]->m_v2 == faceInfo->m_v2) )
			return true;
	}

	return false;
}

///////////////////////////////////////////////////////////////////////////////////////////
// FindStartPoint()
//
// Finds a good starting point, namely one which has only one neighbor
//
int NvStripifier::FindStartPoint(NvFaceInfoVec &faceInfos, NvEdgeInfoVec &edgeInfos)
{
	for(int i = 0; i < faceInfos.size(); i++)
	{
		int ctr = 0;
		
		if(FindOtherFace(edgeInfos, faceInfos[i]->m_v0, faceInfos[i]->m_v1, faceInfos[i]) == NULL)
			ctr++;
		if(FindOtherFace(edgeInfos, faceInfos[i]->m_v1, faceInfos[i]->m_v2, faceInfos[i]) == NULL)
			ctr++;
		if(FindOtherFace(edgeInfos, faceInfos[i]->m_v2, faceInfos[i]->m_v0, faceInfos[i]) == NULL)
			ctr++;
		if(ctr > 1)
			return i;
	}
	return -1;
}

bool NvStripInfo::Unique(NvFaceInfoVec& faceVec, NvFaceInfo* face)
{
	bool bv0, bv1, bv2; //bools to indicate whether a vertex is in the faceVec or not
	bv0 = bv1 = bv2 = false;

	for(size_t i = 0; i < faceVec.size(); i++)
	{
		if(!bv0)
		{
			if( (faceVec[i]->m_v0 == face->m_v0) || 
				(faceVec[i]->m_v1 == face->m_v0) ||
				(faceVec[i]->m_v2 == face->m_v0) )
				bv0 = true;
		}

		if(!bv1)
		{
			if( (faceVec[i]->m_v0 == face->m_v1) || 
				(faceVec[i]->m_v1 == face->m_v1) ||
				(faceVec[i]->m_v2 == face->m_v1) )
				bv1 = true;
		}

		if(!bv2)
		{
			if( (faceVec[i]->m_v0 == face->m_v2) || 
				(faceVec[i]->m_v1 == face->m_v2) ||
				(faceVec[i]->m_v2 == face->m_v2) )
				bv2 = true;
		}

		//the face is not unique, all it's vertices exist in the face vector
		if(bv0 && bv1 && bv2)
			return false;
	}
	
	//if we get out here, it's unique
	return true;
}

////////////////////////////////////////////////////////////////////////////////////////
//Cleanup strips / faces, used by generatestrips
void Cleanup(NvStripInfoVec& tempStrips, NvFaceInfoVec& tempFaces)
{
	//delete strips
	for(size_t i = 0; i < tempStrips.size(); i++)
	{
		for(size_t j = 0; j < tempStrips[i]->m_faces.size(); j++)
		{
			delete tempStrips[i]->m_faces[j];
			tempStrips[i]->m_faces[j] = NULL;
		}
		tempStrips[i]->m_faces.resize(0);
		delete tempStrips[i];
		tempStrips[i] = NULL;
	}

	//delete faces
	for(size_t i = 0; i < tempFaces.size(); i++)
	{
		delete tempFaces[i];
		tempFaces[i] = NULL;
	}
}

////////////////////////////////////////////////////////////////////////////////////////
// GenerateStrips()
//
// in_indices: input index list, the indices you would use to render
// in_numIndices: number of entries in in_indices
// primGroups: array of optimized/stripified PrimitiveGroups
// numGroups: number of groups returned
//
// Be sure to call delete[] on the returned primGroups to avoid leaking mem
//
bool GenerateStrips(const unsigned short* in_indices, const unsigned int in_numIndices,
					PrimitiveGroup** primGroups, unsigned short* numGroups, bool validateEnabled)
{
	int i = 0;
	
	//put data in format that the stripifier likes
	WordVec tempIndices;
	tempIndices.resize(in_numIndices);
	unsigned short maxIndex = 0;
	unsigned short minIndex = 0xFFFF;
	for(i = 0; i < in_numIndices; i++)
	{
		tempIndices[i] = in_indices[i];
		if (in_indices[i] > maxIndex)
			maxIndex = in_indices[i];
		if (in_indices[i] < minIndex)
			minIndex = in_indices[i];
	}
	NvStripInfoVec tempStrips;
	NvFaceInfoVec tempFaces;

	NvStripifier stripifier;
	
	//do actual stripification
	stripifier.Stripify(tempIndices, cacheSize, minStripSize, maxIndex, tempStrips, tempFaces);

	//stitch strips together
	IntVec stripIndices;
	unsigned int numSeparateStrips = 0;

	if(bListsOnly)
	{
		//if we're outputting only lists, we're done
		*numGroups = 1;
		(*primGroups) = new PrimitiveGroup[*numGroups];
		PrimitiveGroup* primGroupArray = *primGroups;

		//count the total number of indices
		unsigned int numIndices = 0;
		for(i = 0; i < tempStrips.size(); i++)
		{
			numIndices += tempStrips[i]->m_faces.size() * 3;
		}

		//add in the list
		numIndices += tempFaces.size() * 3;

		primGroupArray[0].type       = PT_LIST;
		primGroupArray[0].numIndices = numIndices;
		primGroupArray[0].indices    = new unsigned short[numIndices];

		//do strips
		unsigned int indexCtr = 0;
		for(i = 0; i < tempStrips.size(); i++)
		{
			for(int j = 0; j < tempStrips[i]->m_faces.size(); j++)
			{
				//degenerates are of no use with lists
				if(!NvStripifier::IsDegenerate(tempStrips[i]->m_faces[j]))
				{
					primGroupArray[0].indices[indexCtr++] = tempStrips[i]->m_faces[j]->m_v0;
					primGroupArray[0].indices[indexCtr++] = tempStrips[i]->m_faces[j]->m_v1;
					primGroupArray[0].indices[indexCtr++] = tempStrips[i]->m_faces[j]->m_v2;
				}
				else
				{
					//we've removed a tri, reduce the number of indices
					primGroupArray[0].numIndices -= 3;
				}
			}
		}

		//do lists
		for(i = 0; i < tempFaces.size(); i++)
		{			
			primGroupArray[0].indices[indexCtr++] = tempFaces[i]->m_v0;
			primGroupArray[0].indices[indexCtr++] = tempFaces[i]->m_v1;
			primGroupArray[0].indices[indexCtr++] = tempFaces[i]->m_v2;
		}
	}
	else
	{
		stripifier.CreateStrips(tempStrips, stripIndices, bStitchStrips, numSeparateStrips, bRestart, restartVal);

		//if we're stitching strips together, we better get back only one strip from CreateStrips()
		assert( (bStitchStrips && (numSeparateStrips == 1)) || !bStitchStrips);
		
		//convert to output format
		*numGroups = numSeparateStrips; //for the strips
		if(tempFaces.size() != 0)
//.........这里部分代码省略.........

///////////////////////////////////////////////////////////////////////////////////////////
// BuildStripifyInfo()
//
// Builds the list of all face and edge infos
//
void NvStripifier::BuildStripifyInfo(NvFaceInfoVec &faceInfos, NvEdgeInfoVec &edgeInfos,
									 const unsigned short maxIndex)
{
	// reserve space for the face infos, but do not resize them.
	int numIndices = indices.size();
	faceInfos.reserve(numIndices / 3);
	
	// we actually resize the edge infos, so we must initialize to NULL
	edgeInfos.resize(maxIndex + 1);
	for (unsigned short i = 0; i < maxIndex + 1; i++)
		edgeInfos[i] = NULL;
	
	// iterate through the triangles of the triangle list
	int numTriangles = numIndices / 3;
	int index        = 0;
	bool bFaceUpdated[3];

	for (int i = 0; i < numTriangles; i++)
	{	
		bool bMightAlreadyExist = true;
		bFaceUpdated[0] = false;
		bFaceUpdated[1] = false;
		bFaceUpdated[2] = false;

		// grab the indices
		int v0 = indices[index++];
		int v1 = indices[index++];
		int v2 = indices[index++];

		//we disregard degenerates
		if(IsDegenerate(v0, v1, v2))
			continue;
		
		// create the face info and add it to the list of faces, but only if this exact face doesn't already 
		//  exist in the list
		NvFaceInfo *faceInfo = new NvFaceInfo(v0, v1, v2);
		
		// grab the edge infos, creating them if they do not already exist
		NvEdgeInfo *edgeInfo01 = FindEdgeInfo(edgeInfos, v0, v1);
		if (edgeInfo01 == NULL)
		{
			//since one of it's edges isn't in the edge data structure, it can't already exist in the face structure
			bMightAlreadyExist = false;

			// create the info
			edgeInfo01 = new NvEdgeInfo(v0, v1);
			
			// update the linked list on both 
			edgeInfo01->m_nextV0 = edgeInfos[v0];
			edgeInfo01->m_nextV1 = edgeInfos[v1];
			edgeInfos[v0] = edgeInfo01;
			edgeInfos[v1] = edgeInfo01;
			
			// set face 0
			edgeInfo01->m_face0 = faceInfo;
		}
		else 
		{
			if (edgeInfo01->m_face1 != NULL)
			{
				printf("BuildStripifyInfo: > 2 triangles on an edge... uncertain consequences\n");
			}
			else
			{
				edgeInfo01->m_face1 = faceInfo;
				bFaceUpdated[0] = true;
			}
		}
		
		// grab the edge infos, creating them if they do not already exist
		NvEdgeInfo *edgeInfo12 = FindEdgeInfo(edgeInfos, v1, v2);
		if (edgeInfo12 == NULL)
		{
			bMightAlreadyExist = false;
			
			// create the info
			edgeInfo12 = new NvEdgeInfo(v1, v2);
			
			// update the linked list on both 
			edgeInfo12->m_nextV0 = edgeInfos[v1];
			edgeInfo12->m_nextV1 = edgeInfos[v2];
			edgeInfos[v1] = edgeInfo12;
			edgeInfos[v2] = edgeInfo12;
			
			// set face 0
			edgeInfo12->m_face0 = faceInfo;
		}
		else 
		{
			if (edgeInfo12->m_face1 != NULL)
			{
				printf("BuildStripifyInfo: > 2 triangles on an edge... uncertain consequences\n");
			}
			else
			{
//.........这里部分代码省略.........

////////////////////////////////////////////////////////////////////////////////////////
// RemoveSmallStrips()
//
// allStrips is the whole strip vector...all small strips will be deleted from this list, to avoid leaking mem
// allBigStrips is an out parameter which will contain all strips above minStripLength
// faceList is an out parameter which will contain all faces which were removed from the striplist
//
void NvStripifier::RemoveSmallStrips(NvStripInfoVec& allStrips, NvStripInfoVec& allBigStrips, NvFaceInfoVec& faceList)
{
	faceList.clear();
	allBigStrips.clear();  //make sure these are empty
	NvFaceInfoVec tempFaceList;
	
	for(size_t i = 0; i < allStrips.size(); i++)
	{
		if(allStrips[i]->m_faces.size() < (size_t)minStripLength)
		{
			//strip is too small, add faces to faceList
			for(size_t j = 0; j < allStrips[i]->m_faces.size(); j++)
				tempFaceList.push_back(allStrips[i]->m_faces[j]);
			
			//and free memory
			delete allStrips[i];
		}
		else
		{
			allBigStrips.push_back(allStrips[i]);
		}
	}
	
	if(tempFaceList.size())
	{
		bool *bVisitedList = new bool[tempFaceList.size()];
		memset(bVisitedList, 0, tempFaceList.size()*sizeof(bool));
		
		VertexCache* vcache = new VertexCache(cacheSize);
		
		int bestNumHits = -1;
		int numHits;
		int bestIndex;
		
		while(1)
		{
			bestNumHits = -1;
			
			//find best face to add next, given the current cache
			for(size_t i = 0; i < tempFaceList.size(); i++)
			{
				if(bVisitedList[i])
					continue;
				
				numHits = CalcNumHitsFace(vcache, tempFaceList[i]);
				if(numHits > bestNumHits)
				{
					bestNumHits = numHits;
					bestIndex = i;
				}
			}
			
			if(bestNumHits == -1.0f)
				break;
			bVisitedList[bestIndex] = true;
			UpdateCacheFace(vcache, tempFaceList[bestIndex]);
			faceList.push_back(tempFaceList[bestIndex]);
		}
		
		delete vcache;
		delete[] bVisitedList;
	}
}

///////////////////////////////////////////////////////////////////////////////////////////
// Build()
//
// Builds a strip forward as far as we can go, then builds backwards, and joins the two lists
//
void NvStripInfo::Build(NvEdgeInfoVec &edgeInfos, NvFaceInfoVec &faceInfos)
{
	// used in building the strips forward and backward
	WordVec scratchIndices;
	
	// build forward... start with the initial face
	NvFaceInfoVec forwardFaces, backwardFaces;
	forwardFaces.push_back(m_startInfo.m_startFace);

	MarkTriangle(m_startInfo.m_startFace);
	
	int v0 = (m_startInfo.m_toV1 ? m_startInfo.m_startEdge->m_v0 : m_startInfo.m_startEdge->m_v1);
	int v1 = (m_startInfo.m_toV1 ? m_startInfo.m_startEdge->m_v1 : m_startInfo.m_startEdge->m_v0);
	
	// easiest way to get v2 is to use this function which requires the
	// other indices to already be in the list.
	scratchIndices.push_back(v0);
	scratchIndices.push_back(v1);
	int v2 = NvStripifier::GetNextIndex(scratchIndices, m_startInfo.m_startFace);
	scratchIndices.push_back(v2);

	//
	// build the forward list
	//
	int nv0 = v1;
	int nv1 = v2;

	NvFaceInfo *nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, m_startInfo.m_startFace);
	while (nextFace != NULL && !IsMarked(nextFace))
	{
		//check to see if this next face is going to cause us to die soon
		int testnv0 = nv1;
		int testnv1 = NvStripifier::GetNextIndex(scratchIndices, nextFace);
		
		NvFaceInfo* nextNextFace = NvStripifier::FindOtherFace(edgeInfos, testnv0, testnv1, nextFace);

		if( (nextNextFace == NULL) || (IsMarked(nextNextFace)) )
		{
			//uh, oh, we're following a dead end, try swapping
			NvFaceInfo* testNextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, testnv1, nextFace);

			if( ((testNextFace != NULL) && !IsMarked(testNextFace)) )
			{
				//we only swap if it buys us something
				
				//add a "fake" degenerate face
				NvFaceInfo* tempFace = new NvFaceInfo(nv0, nv1, nv0, true);
				
				forwardFaces.push_back(tempFace);
				MarkTriangle(tempFace);

				scratchIndices.push_back(nv0);
				testnv0 = nv0;

				++m_numDegenerates;
			}

		}

		// add this to the strip
		forwardFaces.push_back(nextFace);

		MarkTriangle(nextFace);
		
		// add the index
		//nv0 = nv1;
		//nv1 = NvStripifier::GetNextIndex(scratchIndices, nextFace);
		scratchIndices.push_back(testnv1);
		
		// and get the next face
		nv0 = testnv0;
		nv1 = testnv1;

		nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, nextFace);
	
	}
	
	// tempAllFaces is going to be forwardFaces + backwardFaces
	// it's used for Unique()
	NvFaceInfoVec tempAllFaces;
	for(size_t i = 0; i < forwardFaces.size(); i++)
		tempAllFaces.push_back(forwardFaces[i]);

	//
	// reset the indices for building the strip backwards and do so
	//
	scratchIndices.resize(0);
	scratchIndices.push_back(v2);
	scratchIndices.push_back(v1);
	scratchIndices.push_back(v0);
	nv0 = v1;
	nv1 = v0;
	nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, m_startInfo.m_startFace);
	while (nextFace != NULL && !IsMarked(nextFace))
	{
//.........这里部分代码省略.........

///////////////////////////////////////////////////////////////////////////////////////////
// BuildStripifyInfo()
//
// Builds the list of all face and edge infos
//
void NvStripifier::BuildStripifyInfo(NvFaceInfoVec &faceInfos, NvEdgeInfoVec &edgeInfos){
	
	// reserve space for the face infos, but do not resize them.
	int numIndices = indices.size();
	faceInfos.reserve(numIndices);
	
	// we actually resize the edge infos, so we must initialize to NULL
	edgeInfos.resize (numIndices);
	for (int i = 0; i < numIndices; i++)
		edgeInfos[i] = NULL;
	
	// iterate through the triangles of the triangle list
	int numTriangles = numIndices / 3;
	int index        = 0;
	for (u32 i = 0; i < numTriangles; i++)
	{	
		// grab the indices
		int v0 = indices[index++];
		int v1 = indices[index++];
		int v2 = indices[index++];
		
		// create the face info and add it to the list of faces, but only if this exact face doesn't already 
		//  exist in the list
		NvFaceInfo *faceInfo = xr_new<NvFaceInfo>(v0, v1, v2);
		if(!AlreadyExists(faceInfo, faceInfos))
		{
			faceInfos.push_back(faceInfo);
			
			// grab the edge infos, creating them if they do not already exist
			NvEdgeInfo *edgeInfo01 = FindEdgeInfo(edgeInfos, v0, v1);
			if (edgeInfo01 == NULL){
				
				// create the info
				edgeInfo01 = xr_new<NvEdgeInfo>(v0, v1);
				
				// update the linked list on both 
				edgeInfo01->m_nextV0 = edgeInfos[v0];
				edgeInfo01->m_nextV1 = edgeInfos[v1];
				edgeInfos[v0] = edgeInfo01;
				edgeInfos[v1] = edgeInfo01;
				
				// set face 0
				edgeInfo01->m_face0 = faceInfo;
			}
			else {
				if (edgeInfo01->m_face1 != NULL)	;
					//Msg("! WARNING: BuildStripifyInfo: > 2 triangles on an edge... uncertain consequences");
				else
					edgeInfo01->m_face1 = faceInfo;
			}
			
			// grab the edge infos, creating them if they do not already exist
			NvEdgeInfo *edgeInfo12 = FindEdgeInfo(edgeInfos, v1, v2);
			if (edgeInfo12 == NULL){
				
				// create the info
				edgeInfo12 = xr_new<NvEdgeInfo> (v1, v2);
				
				// update the linked list on both 
				edgeInfo12->m_nextV0 = edgeInfos[v1];
				edgeInfo12->m_nextV1 = edgeInfos[v2];
				edgeInfos[v1] = edgeInfo12;
				edgeInfos[v2] = edgeInfo12;
				
				// set face 0
				edgeInfo12->m_face0 = faceInfo;
			}
			else {
				if (edgeInfo12->m_face1 != NULL)	;
					//Msg("! WARNING: BuildStripifyInfo: > 2 triangles on an edge... uncertain consequences");
				else
					edgeInfo12->m_face1 = faceInfo;
			}
			
			// grab the edge infos, creating them if they do not already exist
			NvEdgeInfo *edgeInfo20 = FindEdgeInfo(edgeInfos, v2, v0);
			if (edgeInfo20 == NULL){
				
				// create the info
				edgeInfo20 = xr_new<NvEdgeInfo>(v2, v0);
				
				// update the linked list on both 
				edgeInfo20->m_nextV0 = edgeInfos[v2];
				edgeInfo20->m_nextV1 = edgeInfos[v0];
				edgeInfos[v2] = edgeInfo20;
				edgeInfos[v0] = edgeInfo20;
				
				// set face 0
				edgeInfo20->m_face0 = faceInfo;
			}
			else {
				if (edgeInfo20->m_face1 != NULL)	;
					//Msg("! WARNING: BuildStripifyInfo: > 2 triangles on an edge... uncertain consequences");
				else
					edgeInfo20->m_face1 = faceInfo;
//.........这里部分代码省略.........

///////////////////////////////////////////////////////////////////////////////////////////
// Build()
//
// Builds a strip forward as far as we can go, then builds backwards, and joins the two lists
//
void NvStripInfo::Build(NvEdgeInfoVec &edgeInfos, NvFaceInfoVec &faceInfos){
	
	// used in building the strips forward and backward
	static WordVec scratchIndices;
	scratchIndices.resize(0);
	
	// build forward... start with the initial face
	NvFaceInfoVec forwardFaces, backwardFaces;
	forwardFaces.push_back(m_startInfo.m_startFace);

	MarkTriangle(m_startInfo.m_startFace);
	
	int v0 = (m_startInfo.m_toV1 ? m_startInfo.m_startEdge->m_v0 : m_startInfo.m_startEdge->m_v1);
	int v1 = (m_startInfo.m_toV1 ? m_startInfo.m_startEdge->m_v1 : m_startInfo.m_startEdge->m_v0);
	
	// easiest way to get v2 is to use this function which requires the
	// other indices to already be in the list.
	scratchIndices.push_back(u16(v0));
	scratchIndices.push_back(u16(v1));
	int v2 = NvStripifier::GetNextIndex(scratchIndices, m_startInfo.m_startFace);
	scratchIndices.push_back(u16(v2));
	
	//
	// build the forward list
	//
	int nv0 = v1;
	int nv1 = v2;
	
	NvFaceInfo *nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, m_startInfo.m_startFace);
	while (nextFace != NULL && !IsMarked(nextFace))
	{
		//this tests to see if a face is "unique", meaning that its vertices aren't already in the list
		// so, strips which "wrap-around" are not allowed
		if(!Unique(forwardFaces, nextFace))
			break;

		// add this to the strip
		forwardFaces.push_back(nextFace);

		MarkTriangle(nextFace);
		
		// add the index
		nv0 = nv1;
		nv1 = NvStripifier::GetNextIndex(scratchIndices, nextFace);
		scratchIndices.push_back(u16(nv1));
		
		// and get the next face
		nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, nextFace);
		
	}
	
	// tempAllFaces is going to be forwardFaces + backwardFaces
	// it's used for Unique()
	NvFaceInfoVec tempAllFaces;
	for(int i = 0; i < forwardFaces.size(); i++)
		tempAllFaces.push_back(forwardFaces[i]);

	//
	// reset the indices for building the strip backwards and do so
	//
	scratchIndices.resize(0);
	scratchIndices.push_back(u16(v2));
	scratchIndices.push_back(u16(v1));
	scratchIndices.push_back(u16(v0));
	nv0 = v1;
	nv1 = v0;
	nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, m_startInfo.m_startFace);
	while (nextFace != NULL && !IsMarked(nextFace))
	{
		//this tests to see if a face is "unique", meaning that its vertices aren't already in the list
		// so, strips which "wrap-around" are not allowed
		if(!Unique(tempAllFaces, nextFace))
			break;

		// add this to the strip
		backwardFaces.push_back(nextFace);
		
		//this is just so Unique() will work
		tempAllFaces.push_back(nextFace);

		MarkTriangle(nextFace);
		
		// add the index
		nv0 = nv1;
		nv1 = NvStripifier::GetNextIndex(scratchIndices, nextFace);
		scratchIndices.push_back(u16(nv1));
		
		// and get the next face
		nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, nextFace);
	}
	
	// Combine the forward and backwards stripification lists and put into our own face vector3
	Combine(forwardFaces, backwardFaces);
}

////////////////////////////////////////////////////////////////////////////////////////
// GenerateStrips()
//
// in_indices: input index list, the indices you would use to render
// in_numIndices: number of entries in in_indices
// primGroups: array of optimized/stripified PrimitiveGroups
// numGroups: number of groups returned
//
// Be sure to call delete[] on the returned primGroups to avoid leaking mem
//
void GenerateStrips(const U16* in_indices, const U32 in_numIndices,
					PrimitiveGroup** primGroups, U16* numGroups)
{
	//put data in format that the stripifier likes
	WordVec tempIndices;
	tempIndices.resize(in_numIndices);
	U16 maxIndex = 0;
   U32 i;
	for(i = 0; i < in_numIndices; i++)
	{
		tempIndices[i] = in_indices[i];
		if(in_indices[i] > maxIndex)
			maxIndex = in_indices[i];
	}
	NvStripInfoVec tempStrips;
	NvFaceInfoVec tempFaces;

	NvStripifier stripifier;
	
	//do actual stripification
	stripifier.Stripify(tempIndices, cacheSize, minStripSize, maxIndex, tempStrips, tempFaces);

	//stitch strips together
	IntVec stripIndices;
	U32 numSeparateStrips = 0;

	if(bListsOnly)
	{
		//if we're outputting only lists, we're done
		*numGroups = 1;
		(*primGroups) = new PrimitiveGroup[*numGroups];
		PrimitiveGroup* primGroupArray = *primGroups;

		//count the total number of indices
		U32 numIndices = 0;
      U32 i;
		for(i = 0; i < tempStrips.size(); i++)
		{
			numIndices += tempStrips[i]->m_faces.size() * 3;
		}

		//add in the list
		numIndices += tempFaces.size() * 3;

		primGroupArray[0].type       = PT_LIST;
		primGroupArray[0].numIndices = numIndices;
		primGroupArray[0].indices    = new U16[numIndices];

		//do strips
		U32 indexCtr = 0;
		for(U32 k = 0; k < tempStrips.size(); k++)
		{
			for(U32 j = 0; j < tempStrips[i]->m_faces.size(); j++)
			{
				//degenerates are of no use with lists
				if(!NvStripifier::IsDegenerate(tempStrips[i]->m_faces[j]))
				{
					primGroupArray[0].indices[indexCtr++] = tempStrips[k]->m_faces[j]->m_v0;
					primGroupArray[0].indices[indexCtr++] = tempStrips[k]->m_faces[j]->m_v1;
					primGroupArray[0].indices[indexCtr++] = tempStrips[k]->m_faces[j]->m_v2;
				}
				else
				{
					//we've removed a tri, reduce the number of indices
					primGroupArray[0].numIndices -= 3;
				}
			}
		}

		//do lists
		for(i = 0; i < tempFaces.size(); i++)
		{
			primGroupArray[0].indices[indexCtr++] = tempFaces[i]->m_v0;
			primGroupArray[0].indices[indexCtr++] = tempFaces[i]->m_v1;
			primGroupArray[0].indices[indexCtr++] = tempFaces[i]->m_v2;
		}
	}
	else
	{
		stripifier.CreateStrips(tempStrips, stripIndices, bStitchStrips, numSeparateStrips);

		//if we're stitching strips together, we better get back only one strip from CreateStrips()
		assert( (bStitchStrips && (numSeparateStrips == 1)) || !bStitchStrips);
		
		//convert to output format
		*numGroups = numSeparateStrips; //for the strips
		if(tempFaces.size() != 0)
			(*numGroups)++;  //we've got a list as well, increment
		(*primGroups) = new PrimitiveGroup[*numGroups];
		
//.........这里部分代码省略.........