Method GetAreaMesh

IO/Geometry/vtkOpenFOAMReader.cxx:10594–10673

#if VTK_FOAMFILE_FINITE_AREA
bool vtkOpenFOAMReaderPrivate::GetAreaMesh(
  vtkPolyData* areaMesh, const vtkSmartPointer<vtkCellArray>& meshFaces, vtkPoints* points)
{
  // Tie to faces instance (like zones etc)
  const std::string timeRegionDir(this->CurrentTimeRegionPath(this->PolyMeshTimeIndexFaces));

  auto& zoneMap = this->areaMeshMap;
  zoneMap.clearAll(); // Remove all old ids and errors

  vtkFoamIOobject io(this->CasePath, this->Parent);

  // Read faMesh/faceLabels
  if (!io.OpenOrGzip(timeRegionDir + "/faMesh/faceLabels"))
  {
    // Not an error if missing
    return true;
  }
  const bool use64BitLabels = io.IsLabel64();

  vtkSmartPointer<vtkDataArray> labelArray;

  {
    vtkFoamEntryValue dict(nullptr);
    dict.SetStreamOption(io);
    try
    {
      if (use64BitLabels)
      {
        dict.ReadNonUniformList<vtkFoamToken::LABELLIST, //
          vtkFoamRead::listTraits<vtkTypeInt64Array, vtkTypeInt64>>(io);
      }
      else
      {
        dict.ReadNonUniformList<vtkFoamToken::LABELLIST, //
          vtkFoamRead::listTraits<vtkTypeInt32Array, vtkTypeInt32>>(io);
      }

      // Capture content as smart pointer
      labelArray.TakeReference(dict.ReleasePtr<vtkDataArray>());
    }
    catch (const vtkFoamError& err)
    {
      vtkErrorMacro(<< "Error reading line " << io.GetLineNumber() << " of " << io.GetFileName()
                    << ": " << err);
      return false;
    }
    io.Close();
  }

  if (labelArray)
  {
    vtkDataArray& labels = *labelArray;
    const vtkIdType nLabels = labels.GetNumberOfTuples();

    // Transcribe into vtkIdList. Don't check for questionable entries just yet
    auto elemIds = vtkSmartPointer<vtkIdList>::New();
    elemIds->SetNumberOfIds(nLabels);