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Added BarycentricRelaxVoronoiSamples and QuadricRelaxVoronoiSamples

This commit is contained in:
Paolo Cignoni 2014-12-04 16:04:20 +00:00
parent 8f04d22bb6
commit 90e07822e5
1 changed files with 52 additions and 8 deletions
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60
vcg/complex/algorithms/voronoi_volume_sampling.h
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@ -180,8 +180,48 @@ ScalarType DistanceFromVoronoiFace(CoordType p_point)
return closestDist; return closestDist;
} }
void BarycentricRelaxVoronoiSamples(int relaxStep)
{
bool changed=false;
assert(montecarloVolumeMesh.vn > seedMesh.vn*20);
int i;
for(i=0;i<relaxStep;++i)
{
std::vector<std::pair<int,CoordType> > sumVec(seedMesh.vn,std::make_pair(0,CoordType(0,0,0)));
for(typename MeshType::VertexIterator vi=montecarloVolumeMesh.vert.begin();vi!=montecarloVolumeMesh.vert.end();++vi)
{
unsigned int seedInd;
ScalarType sqdist;
seedTree->doQueryClosest(vi->P(),seedInd,sqdist);
sumVec[seedInd].first++;
sumVec[seedInd].second+=vi->cP();
}
void RelaxVoronoiSamples(int relaxStep) changed=false;
for(int i=0;i<seedMesh.vert.size();++i)
{
if(sumVec[i].first == 0) tri::Allocator<MeshType>::DeleteVertex(seedMesh,seedMesh.vert[i]);
else
{
CoordType prevP = seedMesh.vert[i].P();
seedMesh.vert[i].P() = sumVec[i].second /ScalarType(sumVec[i].first);
if(prevP != seedMesh.vert[i].P()) changed = true;
}
}
tri::Allocator<MeshType>::CompactVertexVector(seedMesh);
// Kdtree for the seeds must be rebuilt at the end of each step;
VertexConstDataWrapper<MeshType> vdw(seedMesh);
delete seedTree;
seedTree = new KdTree<ScalarType>(vdw);
if(!changed)
break;
}
qDebug("performed %i relax step on %i",i,relaxStep);
}
// Given a volumetric sampling of the mesh, and a set of seeds
void QuadricRelaxVoronoiSamples(int relaxStep)
{ {
bool changed=false; bool changed=false;
assert(montecarloVolumeMesh.vn > seedMesh.vn*20); assert(montecarloVolumeMesh.vn > seedMesh.vn*20);
@ -191,6 +231,9 @@ ScalarType DistanceFromVoronoiFace(CoordType p_point)
QuadricSumDistance dz; QuadricSumDistance dz;
std::vector<QuadricSumDistance> dVec(montecarloVolumeMesh.vert.size(),dz); std::vector<QuadricSumDistance> dVec(montecarloVolumeMesh.vert.size(),dz);
// Each region has a quadric representing the sum of the squared distances of all the points of its region.
// First Loop:
// For each point of the volume add its distance to the quadric of its region.
for(typename MeshType::VertexIterator vi=montecarloVolumeMesh.vert.begin();vi!=montecarloVolumeMesh.vert.end();++vi) for(typename MeshType::VertexIterator vi=montecarloVolumeMesh.vert.begin();vi!=montecarloVolumeMesh.vert.end();++vi)
{ {
unsigned int seedInd; unsigned int seedInd;
@ -199,8 +242,9 @@ ScalarType DistanceFromVoronoiFace(CoordType p_point)
dVec[seedInd].AddPoint(vi->P()); dVec[seedInd].AddPoint(vi->P());
} }
// Search the local maxima for each region and use them as new seeds // Second Loop: Search for each region the point that has minimal squared distance from all other points in that region.
std::vector< std::pair<ScalarType,int> > seedMaximaVec(seedMesh.vert.size(),std::make_pair(std::numeric_limits<ScalarType>::max(),-1 )); // We do that evaluating the quadric in each point
std::vector< std::pair<ScalarType,int> > seedMinimaVec(seedMesh.vert.size(),std::make_pair(std::numeric_limits<ScalarType>::max(),-1 ));
for(typename MeshType::VertexIterator vi=montecarloVolumeMesh.vert.begin();vi!=montecarloVolumeMesh.vert.end();++vi) for(typename MeshType::VertexIterator vi=montecarloVolumeMesh.vert.begin();vi!=montecarloVolumeMesh.vert.end();++vi)
{ {
@ -209,18 +253,18 @@ ScalarType DistanceFromVoronoiFace(CoordType p_point)
seedTree->doQueryClosest(vi->P(),seedInd,sqdist); seedTree->doQueryClosest(vi->P(),seedInd,sqdist);
ScalarType val = dVec[seedInd].Eval(vi->P()); ScalarType val = dVec[seedInd].Eval(vi->P());
if(val < seedMaximaVec[seedInd].first) if(val < seedMinimaVec[seedInd].first)
{ {
seedMaximaVec[seedInd].first = val; seedMinimaVec[seedInd].first = val;
seedMaximaVec[seedInd].second = tri::Index(montecarloVolumeMesh,*vi); seedMinimaVec[seedInd].second = tri::Index(montecarloVolumeMesh,*vi);
} }
} }
changed=false; changed=false;
for(int i=0;i<seedMesh.vert.size();++i) for(int i=0;i<seedMesh.vert.size();++i)
{ {
CoordType prevP = seedMesh.vert[i].P() ; CoordType prevP = seedMesh.vert[i].P() ;
if(seedMaximaVec[i].second == -1) tri::Allocator<MeshType>::DeleteVertex(seedMesh,seedMesh.vert[i]); if(seedMinimaVec[i].second == -1) tri::Allocator<MeshType>::DeleteVertex(seedMesh,seedMesh.vert[i]);
seedMesh.vert[i].P() = montecarloVolumeMesh.vert[seedMaximaVec[i].second].P(); seedMesh.vert[i].P() = montecarloVolumeMesh.vert[seedMinimaVec[i].second].P();
if(prevP != seedMesh.vert[i].P()) changed = true; if(prevP != seedMesh.vert[i].P()) changed = true;
} }
tri::Allocator<MeshType>::CompactVertexVector(seedMesh); tri::Allocator<MeshType>::CompactVertexVector(seedMesh);