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Parameter Tuning for the PoissonDisk sampling using the getBestPrecomputedMontecarloSample heuristic. Now there is a better default and another param exposed.

This commit is contained in:
Paolo Cignoni 2013-09-10 10:50:10 +00:00
parent b849524274
commit 4fdfb1d62b
1 changed files with 50 additions and 38 deletions
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88
vcg/complex/algorithms/point_sampling.h
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@ -1154,37 +1154,6 @@ static void FaceSimilar(MetroMesh & m, VertexSampler &ps,int sampleNum, bool dua
} }
} }
// generate Poisson-disk sample using a set of pre-generated samples (with the Montecarlo algorithm)
// It always return a point.
static VertexPointer getPrecomputedMontecarloSample(Point3i &cell, MontecarloSHT & samplepool,float &currentRadius, bool adaptiveRadiusFlag)
{
MontecarloSHTIterator cellBegin, cellEnd;
samplepool.Grid(cell, cellBegin, cellEnd);
if(adaptiveRadiusFlag) currentRadius = (*cellBegin)->Q();
return *cellBegin;
}
static VertexPointer getBestPrecomputedMontecarloSample(Point3i &cell, MontecarloSHT & samplepool,float &currentRadius, bool adaptiveRadiusFlag)
{
MontecarloSHTIterator cellBegin,cellEnd;
samplepool.Grid(cell, cellBegin, cellEnd);
VertexPointer bestSample=0;
int minRemoveCnt = std::numeric_limits<int>::max();
std::vector<typename MontecarloSHT::HashIterator> inSphVec;
for(MontecarloSHTIterator ci=cellBegin;ci!=cellEnd;++ci)
{
VertexPointer sp = *ci;
if(adaptiveRadiusFlag) currentRadius = sp->Q();
int curRemoveCnt = samplepool.CountInSphere(sp->cP(),currentRadius,inSphVec);
if(curRemoveCnt < minRemoveCnt)
{
bestSample = sp;
minRemoveCnt = curRemoveCnt;
}
}
return bestSample;
}
// check the radius constrain // check the radius constrain
static bool checkPoissonDisk(SampleSHT & sht, const Point3<ScalarType> & p, ScalarType radius) static bool checkPoissonDisk(SampleSHT & sht, const Point3<ScalarType> & p, ScalarType radius)
{ {
@ -1210,6 +1179,7 @@ struct PoissonDiskParam
{ {
adaptiveRadiusFlag = false; adaptiveRadiusFlag = false;
bestSampleChoiceFlag = true; bestSampleChoiceFlag = true;
bestSamplePoolSize = 10;
radiusVariance =1; radiusVariance =1;
MAXLEVELS = 5; MAXLEVELS = 5;
invertQuality = false; invertQuality = false;
@ -1233,16 +1203,53 @@ struct PoissonDiskParam
bool geodesicDistanceFlag; bool geodesicDistanceFlag;
bool bestSampleChoiceFlag; // In poisson disk pruning when we choose a sample in a cell, we choose the sample that remove the minimal number of other samples. This previlege the "on boundary" samples. bool bestSampleChoiceFlag; // In poisson disk pruning when we choose a sample in a cell, we choose the sample that remove the minimal number of other samples. This previlege the "on boundary" samples.
int bestSamplePoolSize;
bool adaptiveRadiusFlag; bool adaptiveRadiusFlag;
float radiusVariance; float radiusVariance;
bool invertQuality; bool invertQuality;
bool preGenFlag; // when generating a poisson distribution, you can initialize the set of computed points with ALL the vertices of another mesh. Useful for building progressive refinements. bool preGenFlag; // when generating a poisson distribution, you can initialize the set of computed points with ALL the vertices of another mesh. Useful for building progressive refinements.
MetroMesh *preGenMesh; MetroMesh *preGenMesh;
int MAXLEVELS; int MAXLEVELS;
Stat *pds; Stat *pds;
}; };
// generate Poisson-disk sample using a set of pre-generated samples (with the Montecarlo algorithm)
// It always return a point.
static VertexPointer getSampleFromCell(Point3i &cell, MontecarloSHT & samplepool)
{
MontecarloSHTIterator cellBegin, cellEnd;
samplepool.Grid(cell, cellBegin, cellEnd);
return *cellBegin;
}
// Given a cell of the grid it search the point that remove the minimum number of other samples
// it linearly scan all the points of a cell.
static VertexPointer getBestPrecomputedMontecarloSample(Point3i &cell, MontecarloSHT & samplepool, ScalarType diskRadius, const PoissonDiskParam &pp)
{
MontecarloSHTIterator cellBegin,cellEnd;
samplepool.Grid(cell, cellBegin, cellEnd);
VertexPointer bestSample=0;
int minRemoveCnt = std::numeric_limits<int>::max();
std::vector<typename MontecarloSHT::HashIterator> inSphVec;
int i=0;
for(MontecarloSHTIterator ci=cellBegin; ci!=cellEnd && i<pp.bestSamplePoolSize; ++ci,i++)
{
VertexPointer sp = *ci;
if(pp.adaptiveRadiusFlag) diskRadius = sp->Q();
int curRemoveCnt = samplepool.CountInSphere(sp->cP(),diskRadius,inSphVec);
if(curRemoveCnt < minRemoveCnt)
{
bestSample = sp;
minRemoveCnt = curRemoveCnt;
}
}
return bestSample;
}
static ScalarType ComputePoissonDiskRadius(MetroMesh &origMesh, int sampleNum) static ScalarType ComputePoissonDiskRadius(MetroMesh &origMesh, int sampleNum)
{ {
ScalarType meshArea = Stat<MetroMesh>::ComputeMeshArea(origMesh); ScalarType meshArea = Stat<MetroMesh>::ComputeMeshArea(origMesh);
@ -1326,7 +1333,7 @@ static void PoissonDiskPruning(VertexSampler &ps, MetroMesh &montecarloMesh,
pp.pds->montecarloSampleNum = montecarloMesh.vn; pp.pds->montecarloSampleNum = montecarloMesh.vn;
} }
int removedCnt=0; int removedCnt=0;
if(pp.preGenFlag) if(pp.preGenFlag && pp.preGenMesh !=0)
{ {
// Initial pass for pruning the Hashed grid with the an eventual pre initialized set of samples // Initial pass for pruning the Hashed grid with the an eventual pre initialized set of samples
for(VertexIterator vi =pp.preGenMesh->vert.begin(); vi!=pp.preGenMesh->vert.end();++vi) for(VertexIterator vi =pp.preGenMesh->vert.begin(); vi!=pp.preGenMesh->vert.end();++vi)
@ -1345,9 +1352,14 @@ static void PoissonDiskPruning(VertexSampler &ps, MetroMesh &montecarloMesh,
if( montecarloSHT.EmptyCell(montecarloSHT.AllocatedCells[i]) ) continue; if( montecarloSHT.EmptyCell(montecarloSHT.AllocatedCells[i]) ) continue;
ScalarType currentRadius =diskRadius; ScalarType currentRadius =diskRadius;
VertexPointer sp; VertexPointer sp;
if(pp.geodesicDistanceFlag) if(pp.bestSampleChoiceFlag)
sp= getPrecomputedMontecarloSample(montecarloSHT.AllocatedCells[i], montecarloSHT, currentRadius, pp.adaptiveRadiusFlag); sp = getBestPrecomputedMontecarloSample(montecarloSHT.AllocatedCells[i], montecarloSHT, diskRadius, pp);
sp = getBestPrecomputedMontecarloSample(montecarloSHT.AllocatedCells[i], montecarloSHT, currentRadius, pp.adaptiveRadiusFlag); else
sp = getSampleFromCell(montecarloSHT.AllocatedCells[i], montecarloSHT);
if(pp.adaptiveRadiusFlag)
currentRadius = sp->Q();
ps.AddVert(*sp); ps.AddVert(*sp);
if(pp.geodesicDistanceFlag) removedCnt += montecarloSHT.RemoveInSphereNormal(sp->cP(),sp->cN(),GDF,currentRadius); if(pp.geodesicDistanceFlag) removedCnt += montecarloSHT.RemoveInSphereNormal(sp->cP(),sp->cN(),GDF,currentRadius);
else removedCnt += montecarloSHT.RemoveInSphere(sp->cP(),currentRadius); else removedCnt += montecarloSHT.RemoveInSphere(sp->cP(),currentRadius);
@ -1648,8 +1660,8 @@ void PoissonSampling(MeshType &m, // the mesh that has to be sampled
// simpler wrapper for the pruning // simpler wrapper for the pruning
// //
template <class MeshType> template <class MeshType>
void PoissonPruning(MeshType &m, // the mesh that has to be sampled void PoissonPruning(MeshType &m, // the mesh that has to be pruned
std::vector<Point3f> &poissonSamples, // the vector that will contain the set of points std::vector<Point3f> &poissonSamples, // the vector that will contain the chosen set of points
float & radius) float & radius)
{ {
typedef tri::TrivialSampler<MeshType> BaseSampler; typedef tri::TrivialSampler<MeshType> BaseSampler;