Method GetCacheOrRead

IO/Exodus/vtkExodusIIReader.cxx:1525–2860

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

//------------------------------------------------------------------------------
vtkDataArray* vtkExodusIIReaderPrivate::GetCacheOrRead(vtkExodusIICacheKey key)
{
  vtkDataArray* arr;
  // Never cache points deflected for a mode shape animation... doubles don't make good keys.
  if (this->HasModeShapes && key.ObjectType == vtkExodusIIReader::NODAL_COORDS)
  {
    arr = nullptr;
  }
  else
  {
    arr = this->Cache->Find(key);
  }

  if (arr)
  {
    //
    return arr;
  }

  int exoid = this->Exoid;
  int maxNameLength = this->Parent->GetMaxNameLength();

  // If array is nullptr, try reading it from file.
  if (key.ObjectType == vtkExodusIIReader::GLOBAL)
  {
    // need to assemble result array from smaller ones.
    // call GetCacheOrRead() for each smaller array
    // pay attention to SqueezePoints

    // ArrayInfoType* ainfop = &this->ArrayInfo[vtkExodusIIReader::GLOBAL][key.ArrayId];
    auto doubleArray = vtkDoubleArray::New();
    arr = doubleArray;
    arr->SetName(vtkExodusIIReaderPrivate::GetGlobalVariableValuesArrayName());
    arr->SetNumberOfComponents(1);
    arr->SetNumberOfTuples(
      static_cast<vtkIdType>(this->ArrayInfo[vtkExodusIIReader::GLOBAL].size()));

    if (ex_get_glob_vars(
          exoid, key.Time + 1, arr->GetNumberOfTuples(), doubleArray->GetPointer(0)) < 0)
    {
      vtkErrorMacro(
        "Could not read global variable " << this->GetGlobalVariableValuesArrayName() << ".");
      arr->Delete();
      arr = nullptr;
    }
    auto info = arr->GetInformation();
    // add the `GLOBAL_VARIABLE` key so filters may use it.
    info->Set(vtkExodusIIReader::GLOBAL_VARIABLE(), 1);
  }
  else if (key.ObjectType == vtkExodusIIReader::NODAL)
  {
    // read nodal array
    ArrayInfoType* ainfop = &this->ArrayInfo[vtkExodusIIReader::NODAL][key.ArrayId];
    int ncomps =
      (this->ModelParameters.num_dim == 2 && ainfop->Components == 2) ? 3 : ainfop->Components;
    arr = vtkDataArray::CreateDataArray(ainfop->StorageType);
    assert(arr->HasStandardMemoryLayout() && "Array must have standard memory layout");
    arr->SetName(ainfop->Name.c_str());