Method SubdivideFromBitsDescriptor

Filters/Sources/vtkHyperTreeGridSource.cxx:1147–1305

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//------------------------------------------------------------------------------
void vtkHyperTreeGridSource::SubdivideFromBitsDescriptor(vtkHyperTreeGrid* output,
  vtkHyperTreeGridNonOrientedCursor* cursor, unsigned int level, int treeIdx, int childIdx,
  int idx[3], int parentPos)
{
  // Get handle on point data
  vtkCellData* outData = output->GetCellData();

  vtkIdType startIdx = this->LevelBitsIndex[level];
  int pointer = level ? childIdx + parentPos * this->BlockSize : treeIdx;

  // Calculate the node global index
  vtkIdType id = this->LevelBitsIndexCnt[level];
  ++this->LevelBitsIndexCnt[level];

  // Set depth array value
  outData->GetArray("Depth")->InsertTuple1(id, level);

  if (this->GenerateInterfaceFields)
  {
    // Set interface arrays values
    double v = 1. / (1 << level);
    outData->GetArray("Normals")->InsertTuple3(id, v, v, v);
    outData->GetArray("Intercepts")->InsertTuple3(id, v, 0., 3.);
  }

  // Initialize global index of tree
  cursor->SetGlobalIndexFromLocal(id);
  bool refine = false;

  if (this->LevelZeroMaterialIndex && level == 0)
  {
    if (this->LevelZeroMaterialMap.find(treeIdx) != this->LevelZeroMaterialMap.end())
    {
      refine = this->DescriptorBits->GetValue(this->LevelZeroMaterialMap[treeIdx]) == 1;
    }
  }
  else
  {
    // Calculate pointer into level descriptor string
    refine = this->DescriptorBits->GetValue(startIdx + pointer) == 1;
  }

  // Subdivide further or stop recursion with terminal leaf
  if (level + 1 < this->MaxDepth && refine)
  {
    // Before subdividing, one should in order:
    // 1) set global index from local
    //    if implicit
    //      set value by tree with SetGlobalIndexStart only once
    //    if explicit
    //      set value by cell with SetGlobalIndexFromLocal
    // 2) if use mask
    //    set mask to false
    if (this->UseMask)
    {
      cursor->SetMask(false);
    }