Method ToChild

Common/DataModel/vtkHyperTreeGridGeometryLevelEntry.cxx:123–200

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//------------------------------------------------------------------------------
void vtkHyperTreeGridGeometryLevelEntry::ToChild(const vtkHyperTreeGrid* grid, unsigned char ichild)
{
  assert("pre: not_tree" && this->Tree);
  assert("pre: not_leaf" && !this->IsLeaf(grid));
  assert("pre: not_valid_child" && ichild < this->Tree->GetNumberOfChildren());
  assert(
    "pre: depth_limiter" && this->Level <= const_cast<vtkHyperTreeGrid*>(grid)->GetDepthLimiter());
  assert("pre: is_masked" && !this->IsMasked(grid));

  const double* sizeChild = this->Tree->GetScales()->ComputeScale(this->Level + 1);

  this->Index = this->Tree->GetElderChildIndex(this->Index) + ichild;

  // Divide cell size and translate origin per template parameter
  switch (this->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];
      break;
    }
    case 9: // dimension = 2, branch factor = 3
    {
      unsigned int axis1 = 0;
      unsigned int axis2 = 1;
      switch (grid->GetOrientation())
      {
        case 0:
          axis1 = 1;
          [[fallthrough]];
        case 1:
          axis2 = 2;
      }
      this->Origin[axis1] += (ichild % 3) * sizeChild[axis1];
      this->Origin[axis2] += ((ichild % 9) / 3) * sizeChild[axis2];