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|
#pragma warning( disable : 4786 4018 4530 )
#include <assert.h>
#include <set>
#include "NvTriStripObjects.h"
#include "VertexCache.h"
#include "tier0/platform.h"
#define CACHE_INEFFICIENCY 6
NvStripifier::NvStripifier()
{
}
NvStripifier::~NvStripifier()
{
}
///////////////////////////////////////////////////////////////////////////////////////////
// FindEdgeInfo()
//
// find the edge info for these two indices
//
NvEdgeInfo * NvStripifier::FindEdgeInfo(NvEdgeInfoVec &edgeInfos, int v0, int v1){
// we can get to it through either array
// because the edge infos have a v0 and v1
// and there is no order except how it was
// first created.
NvEdgeInfo *infoIter = edgeInfos[v0];
while (infoIter != NULL){
if (infoIter->m_v0 == v0){
if (infoIter->m_v1 == v1)
return infoIter;
else
infoIter = infoIter->m_nextV0;
}
else {
assert(infoIter->m_v1 == v0);
if (infoIter->m_v0 == v1)
return infoIter;
else
infoIter = infoIter->m_nextV1;
}
}
return NULL;
}
///////////////////////////////////////////////////////////////////////////////////////////
// FindOtherFace
//
// find the other face sharing these vertices
// exactly like the edge info above
//
NvFaceInfo * NvStripifier::FindOtherFace(NvEdgeInfoVec &edgeInfos, int v0, int v1, NvFaceInfo *faceInfo){
NvEdgeInfo *edgeInfo = FindEdgeInfo(edgeInfos, v0, v1);
if( (edgeInfo == NULL) && (v0 == v1))
{
//we've hit a degenerate
return NULL;
}
assert(edgeInfo != NULL);
return (edgeInfo->m_face0 == faceInfo ? edgeInfo->m_face1 : edgeInfo->m_face0);
}
bool NvStripifier::AlreadyExists(NvFaceInfo* faceInfo, NvFaceInfoVec& faceInfos)
{
for(int 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;
}
///////////////////////////////////////////////////////////////////////////////////////////
// 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 (int 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
{
edgeInfo12->m_face1 = faceInfo;
bFaceUpdated[1] = true;
}
}
// grab the edge infos, creating them if they do not already exist
NvEdgeInfo *edgeInfo20 = FindEdgeInfo(edgeInfos, v2, v0);
if (edgeInfo20 == NULL)
{
bMightAlreadyExist = false;
// create the info
edgeInfo20 = 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)
{
// printf("BuildStripifyInfo: > 2 triangles on an edge... uncertain consequences\n");
}
else
{
edgeInfo20->m_face1 = faceInfo;
bFaceUpdated[2] = true;
}
}
if(bMightAlreadyExist)
{
if(!AlreadyExists(faceInfo, faceInfos))
faceInfos.push_back(faceInfo);
else
{
delete faceInfo;
//cleanup pointers that point to this deleted face
if(bFaceUpdated[0])
edgeInfo01->m_face1 = NULL;
if(bFaceUpdated[1])
edgeInfo12->m_face1 = NULL;
if(bFaceUpdated[2])
edgeInfo20->m_face1 = NULL;
}
}
else
{
faceInfos.push_back(faceInfo);
}
}
}
///////////////////////////////////////////////////////////////////////////////////////////
// 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(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 > bestCtr)
{
bestCtr = ctr;
bestIndex = i;
//return i;
}
}
//return -1;
if(bestCtr == 0)
return -1;
else
return bestIndex;
}
///////////////////////////////////////////////////////////////////////////////////////////
// FindGoodResetPoint()
//
// A good reset point is one near other commited areas so that
// we know that when we've made the longest strips its because
// we're stripifying in the same general orientation.
//
NvFaceInfo* NvStripifier::FindGoodResetPoint(NvFaceInfoVec &faceInfos, NvEdgeInfoVec &edgeInfos){
// we hop into different areas of the mesh to try to get
// other large open spans done. Areas of small strips can
// just be left to triangle lists added at the end.
NvFaceInfo *result = NULL;
if(result == NULL)
{
int numFaces = faceInfos.size();
int startPoint;
if(bFirstTimeResetPoint)
{
//first time, find a face with few neighbors (look for an edge of the mesh)
startPoint = FindStartPoint(faceInfos, edgeInfos);
bFirstTimeResetPoint = false;
}
else
startPoint = (int)(((float) numFaces - 1) * meshJump);
if(startPoint == -1)
{
startPoint = (int)(((float) numFaces - 1) * meshJump);
//meshJump += 0.1f;
//if (meshJump > 1.0f)
// meshJump = .05f;
}
int i = startPoint;
do {
// if this guy isn't visited, try him
if (faceInfos[i]->m_stripId < 0){
result = faceInfos[i];
break;
}
// update the index and clamp to 0-(numFaces-1)
if (++i >= numFaces)
i = 0;
} while (i != startPoint);
// update the meshJump
meshJump += 0.1f;
if (meshJump > 1.0f)
meshJump = .05f;
}
// return the best face we found
return result;
}
///////////////////////////////////////////////////////////////////////////////////////////
// GetUniqueVertexInB()
//
// Returns the vertex unique to faceB
//
int NvStripifier::GetUniqueVertexInB(NvFaceInfo *faceA, NvFaceInfo *faceB){
int facev0 = faceB->m_v0;
if (facev0 != faceA->m_v0 &&
facev0 != faceA->m_v1 &&
facev0 != faceA->m_v2)
return facev0;
int facev1 = faceB->m_v1;
if (facev1 != faceA->m_v0 &&
facev1 != faceA->m_v1 &&
facev1 != faceA->m_v2)
return facev1;
int facev2 = faceB->m_v2;
if (facev2 != faceA->m_v0 &&
facev2 != faceA->m_v1 &&
facev2 != faceA->m_v2)
return facev2;
// nothing is different
return -1;
}
///////////////////////////////////////////////////////////////////////////////////////////
// GetSharedVertices()
//
// Returns the (at most) two vertices shared between the two faces
//
void NvStripifier::GetSharedVertices(NvFaceInfo *faceA, NvFaceInfo *faceB, int* vertex0, int* vertex1)
{
*vertex0 = -1;
*vertex1 = -1;
int facev0 = faceB->m_v0;
if (facev0 == faceA->m_v0 ||
facev0 == faceA->m_v1 ||
facev0 == faceA->m_v2)
{
if(*vertex0 == -1)
*vertex0 = facev0;
else
{
*vertex1 = facev0;
return;
}
}
int facev1 = faceB->m_v1;
if (facev1 == faceA->m_v0 ||
facev1 == faceA->m_v1 ||
facev1 == faceA->m_v2)
{
if(*vertex0 == -1)
*vertex0 = facev1;
else
{
*vertex1 = facev1;
return;
}
}
int facev2 = faceB->m_v2;
if (facev2 == faceA->m_v0 ||
facev2 == faceA->m_v1 ||
facev2 == faceA->m_v2)
{
if(*vertex0 == -1)
*vertex0 = facev2;
else
{
*vertex1 = facev2;
return;
}
}
}
///////////////////////////////////////////////////////////////////////////////////////////
// GetNextIndex()
//
// Returns vertex of the input face which is "next" in the input index list
//
inline int NvStripifier::GetNextIndex(const WordVec &indices, NvFaceInfo *face){
int numIndices = indices.size();
assert(numIndices >= 2);
int v0 = indices[numIndices-2];
int v1 = indices[numIndices-1];
int fv0 = face->m_v0;
int fv1 = face->m_v1;
int fv2 = face->m_v2;
if (fv0 != v0 && fv0 != v1){
if ((fv1 != v0 && fv1 != v1) || (fv2 != v0 && fv2 != v1)){
printf("GetNextIndex: Triangle doesn't have all of its vertices\n");
printf("GetNextIndex: Duplicate triangle probably got us derailed\n");
}
return fv0;
}
if (fv1 != v0 && fv1 != v1){
if ((fv0 != v0 && fv0 != v1) || (fv2 != v0 && fv2 != v1)){
printf("GetNextIndex: Triangle doesn't have all of its vertices\n");
printf("GetNextIndex: Duplicate triangle probably got us derailed\n");
}
return fv1;
}
if (fv2 != v0 && fv2 != v1){
if ((fv0 != v0 && fv0 != v1) || (fv1 != v0 && fv1 != v1)){
printf("GetNextIndex: Triangle doesn't have all of its vertices\n");
printf("GetNextIndex: Duplicate triangle probably got us derailed\n");
}
return fv2;
}
// shouldn't get here, but let's try and fail gracefully
if( (fv0 == fv1) || (fv0 == fv2) )
return fv0;
else if( (fv1 == fv0) || (fv1 == fv2) )
return fv1;
else if( (fv2 == fv0) || (fv2 == fv1) )
return fv2;
else
return -1;
}
///////////////////////////////////////////////////////////////////////////////////////////
// IsMarked()
//
// If either the faceInfo has a real strip index because it is
// already assign to a committed strip OR it is assigned in an
// experiment and the experiment index is the one we are building
// for, then it is marked and unavailable
inline bool NvStripInfo::IsMarked(NvFaceInfo *faceInfo){
return (faceInfo->m_stripId >= 0) || (IsExperiment() && faceInfo->m_experimentId == m_experimentId);
}
///////////////////////////////////////////////////////////////////////////////////////////
// MarkTriangle()
//
// Marks the face with the current strip ID
//
inline void NvStripInfo::MarkTriangle(NvFaceInfo *faceInfo){
assert(!IsMarked(faceInfo));
if (IsExperiment()){
faceInfo->m_experimentId = m_experimentId;
faceInfo->m_testStripId = m_stripId;
}
else{
assert(faceInfo->m_stripId == -1);
faceInfo->m_experimentId = -1;
faceInfo->m_stripId = m_stripId;
}
}
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(int 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;
}
///////////////////////////////////////////////////////////////////////////////////////////
// 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);
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(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(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))
{
//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;
//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);
backwardFaces.push_back(tempFace);
MarkTriangle(tempFace);
scratchIndices.push_back(nv0);
testnv0 = nv0;
++m_numDegenerates;
}
}
// 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(testnv1);
// and get the next face
nv0 = testnv0;
nv1 = testnv1;
nextFace = NvStripifier::FindOtherFace(edgeInfos, nv0, nv1, nextFace);
}
// Combine the forward and backwards stripification lists and put into our own face vector
Combine(forwardFaces, backwardFaces);
}
///////////////////////////////////////////////////////////////////////////////////////////
// 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]);
}
///////////////////////////////////////////////////////////////////////////////////////////
// SharesEdge()
//
// Returns true if the input face and the current strip share an edge
//
bool NvStripInfo::SharesEdge(const NvFaceInfo* faceInfo, NvEdgeInfoVec &edgeInfos)
{
//check v0->v1 edge
NvEdgeInfo* currEdge = NvStripifier::FindEdgeInfo(edgeInfos, faceInfo->m_v0, faceInfo->m_v1);
if(IsInStrip(currEdge->m_face0) || IsInStrip(currEdge->m_face1))
return true;
//check v1->v2 edge
currEdge = NvStripifier::FindEdgeInfo(edgeInfos, faceInfo->m_v1, faceInfo->m_v2);
if(IsInStrip(currEdge->m_face0) || IsInStrip(currEdge->m_face1))
return true;
//check v2->v0 edge
currEdge = NvStripifier::FindEdgeInfo(edgeInfos, faceInfo->m_v2, faceInfo->m_v0);
if(IsInStrip(currEdge->m_face0) || IsInStrip(currEdge->m_face1))
return true;
return false;
}
///////////////////////////////////////////////////////////////////////////////////////////
// CommitStrips()
//
// "Commits" the input strips by setting their m_experimentId to -1 and adding to the allStrips
// vector
//
void NvStripifier::CommitStrips(NvStripInfoVec &allStrips, const NvStripInfoVec &strips)
{
// Iterate through strips
int numStrips = strips.size();
for (int i = 0; i < numStrips; i++){
// Tell the strip that it is now real
NvStripInfo *strip = strips[i];
strip->m_experimentId = -1;
// add to the list of real strips
allStrips.push_back(strip);
// Iterate through the faces of the strip
// Tell the faces of the strip that they belong to a real strip now
const NvFaceInfoVec &faces = strips[i]->m_faces;
int numFaces = faces.size();
for (int j = 0; j < numFaces; j++)
{
strip->MarkTriangle(faces[j]);
}
}
}
///////////////////////////////////////////////////////////////////////////////////////////
// FindTraversal()
//
// Finds the next face to start the next strip on.
//
bool NvStripifier::FindTraversal(NvFaceInfoVec &faceInfos,
NvEdgeInfoVec &edgeInfos,
NvStripInfo *strip,
NvStripStartInfo &startInfo){
// if the strip was v0->v1 on the edge, then v1 will be a vertex in the next edge.
int v = (strip->m_startInfo.m_toV1 ? strip->m_startInfo.m_startEdge->m_v1 : strip->m_startInfo.m_startEdge->m_v0);
NvFaceInfo *untouchedFace = NULL;
NvEdgeInfo *edgeIter = edgeInfos[v];
while (edgeIter != NULL){
NvFaceInfo *face0 = edgeIter->m_face0;
NvFaceInfo *face1 = edgeIter->m_face1;
if ((face0 != NULL && !strip->IsInStrip(face0)) && face1 != NULL && !strip->IsMarked(face1))
{
untouchedFace = face1;
break;
}
if ((face1 != NULL && !strip->IsInStrip(face1)) && face0 != NULL && !strip->IsMarked(face0)){
untouchedFace = face0;
break;
}
// find the next edgeIter
edgeIter = (edgeIter->m_v0 == v ? edgeIter->m_nextV0 : edgeIter->m_nextV1);
}
startInfo.m_startFace = untouchedFace;
startInfo.m_startEdge = edgeIter;
if (edgeIter != NULL)
{
if(strip->SharesEdge(startInfo.m_startFace, edgeInfos))
startInfo.m_toV1 = (edgeIter->m_v0 == v); //note! used to be m_v1
else
startInfo.m_toV1 = (edgeIter->m_v1 == v);
}
return (startInfo.m_startFace != NULL);
}
////////////////////////////////////////////////////////////////////////////////////////
// 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 free memory
delete allStrips[i];
}
else
{
allBigStrips.push_back(allStrips[i]);
}
}
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 = 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]);
}
delete vcache;
delete[] bVisitedList;
}
///////////////////////////////////////////////////////////////////////////////////////////
// NextIsCW()
//
// Returns true if the next face should be ordered in CW fashion
//
bool NvStripifier::NextIsCW(const int numIndices)
{
return ((numIndices % 2) == 0);
}
///////////////////////////////////////////////////////////////////////////////////////////
// IsCW()
//
// Returns true if the face is ordered in CW fashion
//
bool NvStripifier::IsCW(NvFaceInfo *faceInfo, int v0, int v1)
{
if (faceInfo->m_v0 == v0)
return (faceInfo->m_v1 == v1);
else if (faceInfo->m_v1 == v0)
return (faceInfo->m_v2 == v1);
else
return (faceInfo->m_v0 == v1);
// shouldn't get here
assert(0);
return false;
}
bool NvStripifier::FaceContainsIndex(const NvFaceInfo& face, const unsigned int index)
{
return ( (face.m_v0 == (int)index) || (face.m_v1 == (int)index) || (face.m_v2 == (int)index) );
}
bool NvStripifier::IsMoneyFace(const NvFaceInfo& face)
{
if(FaceContainsIndex(face, 800) &&
FaceContainsIndex(face, 812) &&
FaceContainsIndex(face, 731))
return true;
return false;
}
////////////////////////////////////////////////////////////////////////////////////////
// CreateStrips()
//
// Generates actual strips from the list-in-strip-order.
//
void NvStripifier::CreateStrips(const NvStripInfoVec& allStrips, IntVec& stripIndices,
const bool bStitchStrips, unsigned int& numSeparateStrips)
{
assert(numSeparateStrips == 0);
NvFaceInfo tLastFace(0, 0, 0);
NvFaceInfo tPrevStripLastFace(0, 0, 0);
int nStripCount = allStrips.size();
assert(nStripCount > 0);
//we infer the cw/ccw ordering depending on the number of indices
//this is screwed up by the fact that we insert -1s to denote changing strips
//this is to account for that
int accountForNegatives = 0;
for (int i = 0; i < nStripCount; i++)
{
NvStripInfo *strip = allStrips[i];
int nStripFaceCount = strip->m_faces.size();
assert(nStripFaceCount > 0);
// Handle the first face in the strip
{
NvFaceInfo tFirstFace(strip->m_faces[0]->m_v0, strip->m_faces[0]->m_v1, strip->m_faces[0]->m_v2);
// If there is a second face, reorder vertices such that the
// unique vertex is first
if (nStripFaceCount > 1)
{
int nUnique = NvStripifier::GetUniqueVertexInB(strip->m_faces[1], &tFirstFace);
if (nUnique == tFirstFace.m_v1)
{
SWAP(tFirstFace.m_v0, tFirstFace.m_v1);
}
else if (nUnique == tFirstFace.m_v2)
{
SWAP(tFirstFace.m_v0, tFirstFace.m_v2);
}
// If there is a third face, reorder vertices such that the
// shared vertex is last
if (nStripFaceCount > 2)
{
if(IsDegenerate(strip->m_faces[1]))
{
int pivot = strip->m_faces[1]->m_v1;
if(tFirstFace.m_v1 == pivot)
{
SWAP(tFirstFace.m_v1, tFirstFace.m_v2);
}
}
else
{
int nShared0, nShared1;
GetSharedVertices(strip->m_faces[2], &tFirstFace, &nShared0, &nShared1);
if ( (nShared0 == tFirstFace.m_v1) && (nShared1 == -1) )
{
SWAP(tFirstFace.m_v1, tFirstFace.m_v2);
}
}
}
}
if( (i == 0) || !bStitchStrips)
{
if(!IsCW(strip->m_faces[0], tFirstFace.m_v0, tFirstFace.m_v1))
stripIndices.push_back(tFirstFace.m_v0);
}
else
{
// Double tap the first in the new strip
stripIndices.push_back(tFirstFace.m_v0);
// Check CW/CCW ordering
if (NextIsCW(stripIndices.size() - accountForNegatives) != IsCW(strip->m_faces[0], tFirstFace.m_v0, tFirstFace.m_v1))
{
stripIndices.push_back(tFirstFace.m_v0);
}
}
stripIndices.push_back(tFirstFace.m_v0);
stripIndices.push_back(tFirstFace.m_v1);
stripIndices.push_back(tFirstFace.m_v2);
// Update last face info
tLastFace = tFirstFace;
}
for (int j = 1; j < nStripFaceCount; j++)
{
int nUnique = GetUniqueVertexInB(&tLastFace, strip->m_faces[j]);
if (nUnique != -1)
{
stripIndices.push_back(nUnique);
// Update last face info
tLastFace.m_v0 = tLastFace.m_v1;
tLastFace.m_v1 = tLastFace.m_v2;
tLastFace.m_v2 = nUnique;
}
else
{
//we've hit a degenerate
stripIndices.push_back(strip->m_faces[j]->m_v2);
tLastFace.m_v0 = strip->m_faces[j]->m_v0;//tLastFace.m_v1;
tLastFace.m_v1 = strip->m_faces[j]->m_v1;//tLastFace.m_v2;
tLastFace.m_v2 = strip->m_faces[j]->m_v2;//tLastFace.m_v1;
}
}
// Double tap between strips.
if(bStitchStrips)
{
if(i != nStripCount - 1)
stripIndices.push_back(tLastFace.m_v2);
}
else
{
//-1 index indicates next strip
stripIndices.push_back(-1);
accountForNegatives++;
numSeparateStrips++;
}
// Update last face info
tLastFace.m_v0 = tLastFace.m_v1;
tLastFace.m_v1 = tLastFace.m_v2;
tLastFace.m_v2 = tLastFace.m_v2;
}
if(bStitchStrips)
numSeparateStrips = 1;
}
///////////////////////////////////////////////////////////////////////////////////////////
// Stripify()
//
//
// in_indices are the input indices of the mesh to stripify
// in_cacheSize is the target cache size
//
void NvStripifier::Stripify(const WordVec &in_indices, const int in_cacheSize,
const int in_minStripLength, const unsigned short maxIndex,
NvStripInfoVec &outStrips, NvFaceInfoVec& outFaceList)
{
meshJump = 0.0f;
bFirstTimeResetPoint = true; //used in FindGoodResetPoint()
//the number of times to run the experiments
int numSamples = 10;
//the cache size, clamped to one
cacheSize = max(1, in_cacheSize - CACHE_INEFFICIENCY);
minStripLength = in_minStripLength; //this is the strip size threshold below which we dump the strip into a list
indices = in_indices;
// build the stripification info
NvFaceInfoVec allFaceInfos;
NvEdgeInfoVec allEdgeInfos;
BuildStripifyInfo(allFaceInfos, allEdgeInfos, maxIndex);
NvStripInfoVec allStrips;
// stripify
FindAllStrips(allStrips, allFaceInfos, allEdgeInfos, numSamples);
//split up the strips into cache friendly pieces, optimize them, then dump these into outStrips
SplitUpStripsAndOptimize(allStrips, outStrips, allEdgeInfos, outFaceList);
//clean up
for(int i = 0; i < allStrips.size(); i++)
{
delete allStrips[i];
}
for (int i = 0; i < allEdgeInfos.size(); i++)
{
NvEdgeInfo *info = allEdgeInfos[i];
while (info != NULL)
{
NvEdgeInfo *next = (info->m_v0 == i ? info->m_nextV0 : info->m_nextV1);
info->Unref();
info = next;
}
}
}
bool NvStripifier::IsDegenerate(const NvFaceInfo* face)
{
if(face->m_v0 == face->m_v1)
return true;
else if(face->m_v0 == face->m_v2)
return true;
else if(face->m_v1 == face->m_v2)
return true;
else
return false;
}
bool NvStripifier::IsDegenerate(const unsigned short v0, const unsigned short v1, const unsigned short v2)
{
if(v0 == v1)
return true;
else if(v0 == v2)
return true;
else if(v1 == v2)
return true;
else
return false;
}
///////////////////////////////////////////////////////////////////////////////////////////
// SplitUpStripsAndOptimize()
//
// Splits the input vector of strips (allBigStrips) into smaller, cache friendly pieces, then
// reorders these pieces to maximize cache hits
// The final strips are output through outStrips
//
void NvStripifier::SplitUpStripsAndOptimize(NvStripInfoVec &allStrips, NvStripInfoVec &outStrips,
NvEdgeInfoVec& edgeInfos, NvFaceInfoVec& outFaceList)
{
int threshold = cacheSize;
NvStripInfoVec tempStrips;
//split up strips into threshold-sized pieces
for(int i = 0; i < allStrips.size(); i++)
{
NvStripInfo* currentStrip;
NvStripStartInfo startInfo(NULL, NULL, false);
int actualStripSize = 0;
for(int j = 0; j < allStrips[i]->m_faces.size(); ++j)
{
if( !IsDegenerate(allStrips[i]->m_faces[j]) )
actualStripSize++;
}
if(actualStripSize /*allStrips[i]->m_faces.size()*/ > threshold)
{
int numTimes = actualStripSize /*allStrips[i]->m_faces.size()*/ / threshold;
int numLeftover = actualStripSize /*allStrips[i]->m_faces.size()*/ % threshold;
int degenerateCount = 0;
int j = 0;
for(j; j < numTimes; j++)
{
currentStrip = new NvStripInfo(startInfo, 0, -1);
int faceCtr = j*threshold + degenerateCount;
bool bFirstTime = true;
while(faceCtr < threshold+(j*threshold)+degenerateCount)
{
if(IsDegenerate(allStrips[i]->m_faces[faceCtr]))
{
degenerateCount++;
//last time or first time through, no need for a degenerate
if( (((faceCtr + 1) != threshold+(j*threshold)+degenerateCount) ||
((j == numTimes - 1) && (numLeftover < 4) && (numLeftover > 0))) &&
!bFirstTime)
{
currentStrip->m_faces.push_back(allStrips[i]->m_faces[faceCtr++]);
}
else
++faceCtr;
}
else
{
currentStrip->m_faces.push_back(allStrips[i]->m_faces[faceCtr++]);
bFirstTime = false;
}
}
/*
for(int faceCtr = j*threshold; faceCtr < threshold+(j*threshold); faceCtr++)
{
currentStrip->m_faces.push_back(allStrips[i]->m_faces[faceCtr]);
}
*/
///*
if(j == numTimes - 1) //last time through
{
if( (numLeftover < 4) && (numLeftover > 0) ) //way too small
{
//just add to last strip
int ctr = 0;
while(ctr < numLeftover)
{
if(!IsDegenerate(allStrips[i]->m_faces[faceCtr]))
{
currentStrip->m_faces.push_back(allStrips[i]->m_faces[faceCtr++]);
++ctr;
}
else
{
currentStrip->m_faces.push_back(allStrips[i]->m_faces[faceCtr++]);
++degenerateCount;
}
}
numLeftover = 0;
}
}
//*/
tempStrips.push_back(currentStrip);
}
int leftOff = j * threshold + degenerateCount;
if(numLeftover != 0)
{
currentStrip = new NvStripInfo(startInfo, 0, -1);
int ctr = 0;
bool bFirstTime = true;
while(ctr < numLeftover)
{
if( !IsDegenerate(allStrips[i]->m_faces[leftOff]) )
{
ctr++;
bFirstTime = false;
currentStrip->m_faces.push_back(allStrips[i]->m_faces[leftOff++]);
}
else if(!bFirstTime)
currentStrip->m_faces.push_back(allStrips[i]->m_faces[leftOff++]);
else
leftOff++;
}
/*
for(int k = 0; k < numLeftover; k++)
{
currentStrip->m_faces.push_back(allStrips[i]->m_faces[leftOff++]);
}
*/
tempStrips.push_back(currentStrip);
}
}
else
{
//we're not just doing a tempStrips.push_back(allBigStrips[i]) because
// this way we can delete allBigStrips later to free the memory
currentStrip = new NvStripInfo(startInfo, 0, -1);
for(int j = 0; j < allStrips[i]->m_faces.size(); j++)
currentStrip->m_faces.push_back(allStrips[i]->m_faces[j]);
tempStrips.push_back(currentStrip);
}
}
//add small strips to face list
NvStripInfoVec tempStrips2;
RemoveSmallStrips(tempStrips, tempStrips2, outFaceList);
outStrips.clear();
//screw optimization for now
// for(i = 0; i < tempStrips.size(); ++i)
// outStrips.push_back(tempStrips[i]);
if(tempStrips2.size() != 0)
{
//Optimize for the vertex cache
VertexCache* vcache = new VertexCache(cacheSize);
float bestNumHits = -1.0f;
float numHits;
int bestIndex = 0;
int firstIndex = 0;
float minCost = 10000.0f;
for(int i = 0; i < tempStrips2.size(); i++)
{
int numNeighbors = 0;
//find strip with least number of neighbors per face
for(int j = 0; j < tempStrips2[i]->m_faces.size(); j++)
{
numNeighbors += NumNeighbors(tempStrips2[i]->m_faces[j], edgeInfos);
}
float currCost = (float)numNeighbors / (float)tempStrips2[i]->m_faces.size();
if(currCost < minCost)
{
minCost = currCost;
firstIndex = i;
}
}
UpdateCacheStrip(vcache, tempStrips2[firstIndex]);
outStrips.push_back(tempStrips2[firstIndex]);
tempStrips2[firstIndex]->visited = true;
bool bWantsCW = (tempStrips2[firstIndex]->m_faces.size() % 2) == 0;
//this n^2 algo is what slows down stripification so much....
// needs to be improved
while(1)
{
bestNumHits = -1.0f;
//find best strip to add next, given the current cache
for(int i = 0; i < tempStrips2.size(); i++)
{
if(tempStrips2[i]->visited)
continue;
numHits = CalcNumHitsStrip(vcache, tempStrips2[i]);
if(numHits > bestNumHits)
{
bestNumHits = numHits;
bestIndex = i;
}
else if(numHits >= bestNumHits)
{
//check previous strip to see if this one requires it to switch polarity
NvStripInfo *strip = tempStrips2[i];
int nStripFaceCount = strip->m_faces.size();
NvFaceInfo tFirstFace(strip->m_faces[0]->m_v0, strip->m_faces[0]->m_v1, strip->m_faces[0]->m_v2);
// If there is a second face, reorder vertices such that the
// unique vertex is first
if (nStripFaceCount > 1)
{
int nUnique = NvStripifier::GetUniqueVertexInB(strip->m_faces[1], &tFirstFace);
if (nUnique == tFirstFace.m_v1)
{
SWAP(tFirstFace.m_v0, tFirstFace.m_v1);
}
else if (nUnique == tFirstFace.m_v2)
{
SWAP(tFirstFace.m_v0, tFirstFace.m_v2);
}
// If there is a third face, reorder vertices such that the
// shared vertex is last
if (nStripFaceCount > 2)
{
int nShared0, nShared1;
GetSharedVertices(strip->m_faces[2], &tFirstFace, &nShared0, &nShared1);
if ( (nShared0 == tFirstFace.m_v1) && (nShared1 == -1) )
{
SWAP(tFirstFace.m_v1, tFirstFace.m_v2);
}
}
}
// Check CW/CCW ordering
if (bWantsCW == IsCW(strip->m_faces[0], tFirstFace.m_v0, tFirstFace.m_v1))
{
//I like this one!
bestIndex = i;
}
}
}
if(bestNumHits == -1.0f)
break;
tempStrips2[bestIndex]->visited = true;
UpdateCacheStrip(vcache, tempStrips2[bestIndex]);
outStrips.push_back(tempStrips2[bestIndex]);
bWantsCW = (tempStrips2[bestIndex]->m_faces.size() % 2 == 0) ? bWantsCW : !bWantsCW;
}
delete vcache;
}
}
///////////////////////////////////////////////////////////////////////////////////////////
// UpdateCacheStrip()
//
// Updates the input vertex cache with this strip's vertices
//
void NvStripifier::UpdateCacheStrip(VertexCache* vcache, NvStripInfo* strip)
{
for(int i = 0; i < strip->m_faces.size(); ++i)
{
if(!vcache->InCache(strip->m_faces[i]->m_v0))
vcache->AddEntry(strip->m_faces[i]->m_v0);
if(!vcache->InCache(strip->m_faces[i]->m_v1))
vcache->AddEntry(strip->m_faces[i]->m_v1);
if(!vcache->InCache(strip->m_faces[i]->m_v2))
vcache->AddEntry(strip->m_faces[i]->m_v2);
}
}
///////////////////////////////////////////////////////////////////////////////////////////
// UpdateCacheFace()
//
// Updates the input vertex cache with this face's vertices
//
void NvStripifier::UpdateCacheFace(VertexCache* vcache, NvFaceInfo* face)
{
if(!vcache->InCache(face->m_v0))
vcache->AddEntry(face->m_v0);
if(!vcache->InCache(face->m_v1))
vcache->AddEntry(face->m_v1);
if(!vcache->InCache(face->m_v2))
vcache->AddEntry(face->m_v2);
}
///////////////////////////////////////////////////////////////////////////////////////////
// CalcNumHitsStrip()
//
// returns the number of cache hits per face in the strip
//
float NvStripifier::CalcNumHitsStrip(VertexCache* vcache, NvStripInfo* strip)
{
int numHits = 0;
int numFaces = 0;
for(int i = 0; i < strip->m_faces.size(); i++)
{
if(vcache->InCache(strip->m_faces[i]->m_v0))
++numHits;
if(vcache->InCache(strip->m_faces[i]->m_v1))
++numHits;
if(vcache->InCache(strip->m_faces[i]->m_v2))
++numHits;
numFaces++;
}
return ((float)numHits / (float)numFaces);
}
///////////////////////////////////////////////////////////////////////////////////////////
// CalcNumHitsFace()
//
// returns the number of cache hits in the face
//
int NvStripifier::CalcNumHitsFace(VertexCache* vcache, NvFaceInfo* face)
{
int numHits = 0;
if(vcache->InCache(face->m_v0))
numHits++;
if(vcache->InCache(face->m_v1))
numHits++;
if(vcache->InCache(face->m_v2))
numHits++;
return numHits;
}
///////////////////////////////////////////////////////////////////////////////////////////
// NumNeighbors()
//
// Returns the number of neighbors that this face has
//
int NvStripifier::NumNeighbors(NvFaceInfo* face, NvEdgeInfoVec& edgeInfoVec)
{
int numNeighbors = 0;
if(FindOtherFace(edgeInfoVec, face->m_v0, face->m_v1, face) != NULL)
{
numNeighbors++;
}
if(FindOtherFace(edgeInfoVec, face->m_v1, face->m_v2, face) != NULL)
{
numNeighbors++;
}
if(FindOtherFace(edgeInfoVec, face->m_v2, face->m_v0, face) != NULL)
{
numNeighbors++;
}
return numNeighbors;
}
///////////////////////////////////////////////////////////////////////////////////////////
// AvgStripSize()
//
// Finds the average strip size of the input vector of strips
//
float NvStripifier::AvgStripSize(const NvStripInfoVec &strips){
int sizeAccum = 0;
int numStrips = strips.size();
for (int i = 0; i < numStrips; i++){
NvStripInfo *strip = strips[i];
sizeAccum += strip->m_faces.size();
sizeAccum -= strip->m_numDegenerates;
}
return ((float)sizeAccum) / ((float)numStrips);
}
///////////////////////////////////////////////////////////////////////////////////////////
// FindAllStrips()
//
// Does the stripification, puts output strips into vector allStrips
//
// Works by setting runnning a number of experiments in different areas of the mesh, and
// accepting the one which results in the longest strips. It then accepts this, and moves
// on to a different area of the mesh. We try to jump around the mesh some, to ensure that
// large open spans of strips get generated.
//
void NvStripifier::FindAllStrips(NvStripInfoVec &allStrips,
NvFaceInfoVec &allFaceInfos,
NvEdgeInfoVec &allEdgeInfos,
int numSamples){
// the experiments
int experimentId = 0;
int stripId = 0;
bool done = false;
int loopCtr = 0;
while (!done)
{
loopCtr++;
//
// PHASE 1: Set up numSamples * numEdges experiments
//
NvStripInfoVec *experiments = new NvStripInfoVec [numSamples * 6];
int experimentIndex = 0;
std::set <NvFaceInfo*> resetPoints;
for (int i = 0; i < numSamples; i++)
{
// Try to find another good reset point.
// If there are none to be found, we are done
NvFaceInfo *nextFace = FindGoodResetPoint(allFaceInfos, allEdgeInfos);
if (nextFace == NULL){
done = true;
break;
}
// If we have already evaluated starting at this face in this slew
// of experiments, then skip going any further
else if (resetPoints.find(nextFace) != resetPoints.end()){
continue;
}
// trying it now...
resetPoints.insert(nextFace);
// otherwise, we shall now try experiments for starting on the 01,12, and 20 edges
assert(nextFace->m_stripId < 0);
// build the strip off of this face's 0-1 edge
NvEdgeInfo *edge01 = FindEdgeInfo(allEdgeInfos, nextFace->m_v0, nextFace->m_v1);
NvStripInfo *strip01 = new NvStripInfo(NvStripStartInfo(nextFace, edge01, true), stripId++, experimentId++);
experiments[experimentIndex++].push_back(strip01);
// build the strip off of this face's 1-0 edge
NvEdgeInfo *edge10 = FindEdgeInfo(allEdgeInfos, nextFace->m_v0, nextFace->m_v1);
NvStripInfo *strip10 = new NvStripInfo(NvStripStartInfo(nextFace, edge10, false), stripId++, experimentId++);
experiments[experimentIndex++].push_back(strip10);
// build the strip off of this face's 1-2 edge
NvEdgeInfo *edge12 = FindEdgeInfo(allEdgeInfos, nextFace->m_v1, nextFace->m_v2);
NvStripInfo *strip12 = new NvStripInfo(NvStripStartInfo(nextFace, edge12, true), stripId++, experimentId++);
experiments[experimentIndex++].push_back(strip12);
// build the strip off of this face's 2-1 edge
NvEdgeInfo *edge21 = FindEdgeInfo(allEdgeInfos, nextFace->m_v1, nextFace->m_v2);
NvStripInfo *strip21 = new NvStripInfo(NvStripStartInfo(nextFace, edge21, false), stripId++, experimentId++);
experiments[experimentIndex++].push_back(strip21);
// build the strip off of this face's 2-0 edge
NvEdgeInfo *edge20 = FindEdgeInfo(allEdgeInfos, nextFace->m_v2, nextFace->m_v0);
NvStripInfo *strip20 = new NvStripInfo(NvStripStartInfo(nextFace, edge20, true), stripId++, experimentId++);
experiments[experimentIndex++].push_back(strip20);
// build the strip off of this face's 0-2 edge
NvEdgeInfo *edge02 = FindEdgeInfo(allEdgeInfos, nextFace->m_v2, nextFace->m_v0);
NvStripInfo *strip02 = new NvStripInfo(NvStripStartInfo(nextFace, edge02, false), stripId++, experimentId++);
experiments[experimentIndex++].push_back(strip02);
}
//
// PHASE 2: Iterate through that we setup in the last phase
// and really build each of the strips and strips that follow to see how
// far we get
//
int numExperiments = experimentIndex;
for (int i = 0; i < numExperiments; i++){
// get the strip set
// build the first strip of the list
experiments[i][0]->Build(allEdgeInfos, allFaceInfos);
int experimentId = experiments[i][0]->m_experimentId;
NvStripInfo *stripIter = experiments[i][0];
NvStripStartInfo startInfo(NULL, NULL, false);
while (FindTraversal(allFaceInfos, allEdgeInfos, stripIter, startInfo)){
// create the new strip info
stripIter = new NvStripInfo(startInfo, stripId++, experimentId);
// build the next strip
stripIter->Build(allEdgeInfos, allFaceInfos);
// add it to the list
experiments[i].push_back(stripIter);
}
}
//
// Phase 3: Find the experiment that has the most promise
//
int bestIndex = 0;
double bestValue = 0;
for (int i = 0; i < numExperiments; i++)
{
const float avgStripSizeWeight = 1.0f;
// const float numTrisWeight = 0.0f;
const float numStripsWeight = 0.0f;
float avgStripSize = AvgStripSize(experiments[i]);
float numStrips = (float) experiments[i].size();
float value = avgStripSize * avgStripSizeWeight + (numStrips * numStripsWeight);
//float value = 1.f / numStrips;
//float value = numStrips * avgStripSize;
if (value > bestValue)
{
bestValue = value;
bestIndex = i;
}
}
//
// Phase 4: commit the best experiment of the bunch
//
CommitStrips(allStrips, experiments[bestIndex]);
// and destroy all of the others
for (int i = 0; i < numExperiments; i++)
{
if (i != bestIndex)
{
int numStrips = experiments[i].size();
for (int j = 0; j < numStrips; j++)
{
delete experiments[i][j];
}
}
}
// delete the array that we used for all experiments
delete [] experiments;
}
}
///////////////////////////////////////////////////////////////////////////////////////////
// CountRemainingTris()
//
// This will count the number of triangles left in the
// strip list starting at iter and finishing up at end
//
int NvStripifier::CountRemainingTris(std::list<NvStripInfo*>::iterator iter,
std::list<NvStripInfo*>::iterator end){
int count = 0;
while (iter != end){
count += (*iter)->m_faces.size();
iter++;
}
return count;
}
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