Method ToChild

Common/DataModel/vtkHyperTreeGridGeometryUnlimitedEntry.cxx:154–245

------------------------------------------------------------------------------

//------------------------------------------------------------------------------
void vtkHyperTreeGridGeometryUnlimitedEntry::ToChild(const vtkHyperTreeGrid* grid,
  const vtkHyperTree* tree, unsigned int vtkNotUsed(level), const double* sizeChild,
  unsigned char ichild)
{
  assert("pre: not_tree" && tree);
  assert("pre: is_masked" && !IsMasked(grid, tree));

  size_t indexMax = 0;
  tree->GetElderChildIndexArray(indexMax);
  if (this->Index >= 0 && this->Index < static_cast<vtkIdType>(indexMax))
  {
    vtkIdType elder = tree->GetElderChildIndex(this->Index);
    if (elder != static_cast<vtkIdType>(std::numeric_limits<unsigned int>::max()))
    {
      this->Index = elder + ichild;
      this->LastRealIndex = this->Index;
    }
    else
    {
      // first virtual cell
      this->Index = vtkHyperTreeGrid::InvalidIndex;
    }
  }
  else
  {
    // cell is already virtual
    this->Index = vtkHyperTreeGrid::InvalidIndex;
  }

  // Divide cell size and translate origin per template parameter
  switch (tree->GetNumberOfChildren())
  {
    case 2: // dimension = 1, branch factor = 2
    {
      unsigned int axis = grid->GetOrientation();
      this->Origin[axis] += (ichild & 1) * sizeChild[axis];
      break;
    }
    case 3: // dimension = 1, branch factor = 3
    {
      unsigned int axis = grid->GetOrientation();
      this->Origin[axis] += (ichild % 3) * sizeChild[axis];
      break;
    }
    case 4: // dimension = 2, branch factor = 2
    {
      unsigned int axis1 = 0;
      unsigned int axis2 = 1;
      switch (grid->GetOrientation())
      {
        case 0:
          axis1 = 1;
          [[fallthrough]];
        case 1:
          axis2 = 2;
      }
      this->Origin[axis1] += (ichild & 1) * sizeChild[axis1];
      this->Origin[axis2] += ((ichild & 2) >> 1) * sizeChild[axis2];