void mitk::UnstructuredGridClusteringFilter::ExpandCluster(int id, vtkIdList *pointIDs, vtkPoints* cluster, vtkPoints* inpPoints)
{
std::vector<int> x;
x.push_back(id);
cluster->InsertNextPoint(inpPoints->GetPoint(id)); //add P to cluster C
clusterMember[id] = true;
vtkSmartPointer<vtkPoints> neighbours = vtkSmartPointer<vtkPoints>::New(); //same N as in other function
inpPoints->GetPoints(pointIDs,neighbours);
for(int i=0; i<pointIDs->GetNumberOfIds();i++) //for each point P' in N
{
if(!visited[pointIDs->GetId(i)]) //if P' is not visited
{
visited[pointIDs->GetId(i)] = true; //mark P' as visited
vtkSmartPointer<vtkIdList> idList = vtkSmartPointer<vtkIdList>::New(); //represent N'
pLocator->FindPointsWithinRadius(m_eps, inpPoints->GetPoint(pointIDs->GetId(i)), idList); //N' = D.regionQuery(P', eps)
if(idList->GetNumberOfIds() >= m_MinPts) //if sizeof(N') >= MinPts
{
for(int j=0; j<idList->GetNumberOfIds();j++) //N = N joined with N'
{
if(idList->GetId(j)<inpPoints->GetNumberOfPoints())//a litte bit hacked ?!
{
pointIDs->InsertNextId(idList->GetId(j));
}
}
}
}
if(!clusterMember[pointIDs->GetId(i)]) //if P' is not yet member of any cluster
{
if(pointIDs->GetId(i)<inpPoints->GetNumberOfPoints()){
clusterMember[pointIDs->GetId(i)] = true;
x.push_back(pointIDs->GetId(i));
cluster->InsertNextPoint(inpPoints->GetPoint(pointIDs->GetId(i))); //add P' to cluster C
}
}
}
clustersPointsIDs.push_back(x);
}
void mitk::UnstructuredGridClusteringFilter::GenerateData()
{
mitk::UnstructuredGrid::Pointer inputGrid = const_cast<mitk::UnstructuredGrid*>(this->GetInput());
if(inputGrid.IsNull()) return;
vtkSmartPointer<vtkUnstructuredGrid> vtkInpGrid = inputGrid->GetVtkUnstructuredGrid();
vtkSmartPointer<vtkPoints> inpPoints = vtkInpGrid->GetPoints();
pLocator =vtkSmartPointer<vtkPointLocator>::New();
vtkSmartPointer<vtkDoubleArray> distances = vtkSmartPointer<vtkDoubleArray>::New();
if(inputGrid->GetVtkUnstructuredGrid()->GetPointData()->GetNumberOfArrays() > 0)
{
m_DistCalc = true;
distances = dynamic_cast<vtkDoubleArray*>(vtkInpGrid->GetPointData()->GetArray(0));
}
pLocator->SetDataSet(vtkInpGrid);
pLocator->AutomaticOn();
pLocator->SetNumberOfPointsPerBucket(2);
pLocator->BuildLocator();
//fill the visited map with false for checking
for(int i=0; i<inpPoints->GetNumberOfPoints();i++)
{
visited[i] = false;
isNoise[i] = false;
clusterMember[i] = false;
}
for(int i=0; i<inpPoints->GetNumberOfPoints();i++)
{
if(!visited[i])
{
visited[i] = true; //mark P as visited
vtkSmartPointer<vtkIdList> idList = vtkSmartPointer<vtkIdList>::New(); //represent N
pLocator->FindPointsWithinRadius(m_eps, inpPoints->GetPoint(i), idList); //N = D.regionQuery(P, eps)
if(idList->GetNumberOfIds() < m_MinPts) //if sizeof(N) < MinPts
{
isNoise[i] = true; //mark P as NOISE
}
else
{
vtkSmartPointer<vtkPoints> cluster = vtkSmartPointer<vtkPoints>::New(); //represent a cluster
clusterVector.push_back(cluster); //C = next cluster
this->ExpandCluster(i,idList,cluster,inpPoints); //expandCluster(P, N, C, eps, MinPts) mod. the parameter list
}
}
}
//OUTPUT LOGIC
m_Clusters = clusterVector;
int numberOfClusterPoints = 0;
int IdOfBiggestCluster = 0;
for(unsigned int i=0; i<m_Clusters.size();i++)
{
vtkSmartPointer<vtkDoubleArray> array = vtkSmartPointer<vtkDoubleArray>::New();
vtkSmartPointer<vtkPoints> points = m_Clusters.at(i);
if(m_DistCalc)
{
array->SetNumberOfComponents(1);
array->SetNumberOfTuples(points->GetNumberOfPoints());
for(int j=0; j<points->GetNumberOfPoints();j++)
{
double point[3];
points->GetPoint(j,point);
if(clustersPointsIDs.at(i).at(j)<inpPoints->GetNumberOfPoints())
{
if(distances->GetValue(clustersPointsIDs.at(i).at(j)) > 0.001)
{
double dist[1] = {distances->GetValue(clustersPointsIDs.at(i).at(j))};
array->SetTuple(j, dist);
}
else
{
double dist[1] = {0.0};
array->SetTuple(j, dist);
}
}
}
m_DistanceArrays.push_back(array);
}
if(points->GetNumberOfPoints() > numberOfClusterPoints)
{
numberOfClusterPoints = points->GetNumberOfPoints();
IdOfBiggestCluster = i;
}
}
vtkSmartPointer<vtkUnstructuredGrid> biggestCluster = vtkSmartPointer<vtkUnstructuredGrid>::New();
vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
points = m_Clusters.at(IdOfBiggestCluster);
vtkSmartPointer<vtkPolyVertex> verts = vtkSmartPointer<vtkPolyVertex>::New();
verts->GetPointIds()->SetNumberOfIds(m_Clusters.at(IdOfBiggestCluster)->GetNumberOfPoints());
for(int i=0; i<m_Clusters.at(IdOfBiggestCluster)->GetNumberOfPoints(); i++)
{
verts->GetPointIds()->SetId(i,i);
}
biggestCluster->Allocate(1);
biggestCluster->InsertNextCell(verts->GetCellType(), verts->GetPointIds());
biggestCluster->SetPoints(m_Clusters.at(IdOfBiggestCluster));
if(m_Meshing)
{
vtkSmartPointer<vtkDelaunay3D> mesher = vtkSmartPointer<vtkDelaunay3D>::New();
mesher->SetInputData(biggestCluster);
mesher->SetAlpha(0.9);
mesher->Update();
vtkSmartPointer<vtkUnstructuredGrid> output = mesher->GetOutput();
m_UnstructGrid->SetVtkUnstructuredGrid(output);
}
else
{
m_UnstructGrid->SetVtkUnstructuredGrid(biggestCluster);
}
clusterVector.clear();
clustersPointsIDs.clear();
}