Method GetCellNeighbors

Common/DataModel/vtkUnstructuredGrid.cxx:1698–1731

---------------------------------------------------------------------------- Return the cells that use all of the ptIds provided. This is a set (intersection) operation - it can have significant performance impacts on certain filters like vtkGeometryFilter.

// (intersection) operation - it can have significant performance impacts on
// certain filters like vtkGeometryFilter.
void vtkUnstructuredGrid::GetCellNeighbors(
  vtkIdType cellId, vtkIdType npts, const vtkIdType* pts, vtkIdList* cellIds)
{
  // Empty the list
  cellIds->Reset();

  // Ensure that a proper neighborhood request is made.
  if (npts <= 0)
  {
    return;
  }

  // Ensure that links are built.
  if (!this->Links)
  {
    this->BuildLinks();
  }

  // Get the cell links based on the current state.
  if (!this->Editable)
  {
    using CellLinksType = vtkStaticCellLinks;
    using TGetCellNeighbors = GetCellNeighborsImpl<CellLinksType>;
    auto links = static_cast<CellLinksType*>(this->Links.Get());
    this->Connectivity->Dispatch(TGetCellNeighbors{}, links, cellId, npts, pts, cellIds);
  }
  else
  {
    using CellLinksType = vtkCellLinks;
    using TGetCellNeighbors = GetCellNeighborsImpl<CellLinksType>;
    auto links = static_cast<CellLinksType*>(this->Links.Get());
    this->Connectivity->Dispatch(TGetCellNeighbors{}, links, cellId, npts, pts, cellIds);
  }
}

//------------------------------------------------------------------------------
int vtkUnstructuredGrid::GetCellNumberOfFaces(