Method RequestData

IO/Image/vtkNIFTIImageReader.cxx:1029–1355

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

//------------------------------------------------------------------------------
int vtkNIFTIImageReader::RequestData(vtkInformation* request,
  vtkInformationVector** vtkNotUsed(inputVector), vtkInformationVector* outputVector)
{
  // check whether the reader is in an error state
  if (this->GetErrorCode() != vtkErrorCode::NoError)
  {
    return 0;
  }

  // which output port did the request come from
  int outputPort = request->Get(vtkDemandDrivenPipeline::FROM_OUTPUT_PORT());

  // for now, this reader has only one output
  if (outputPort > 0)
  {
    return 1;
  }

  vtkInformation* outInfo = outputVector->GetInformationObject(0);

  int extent[6];
  outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_EXTENT(), extent);

  // get the data object, allocate memory
  vtkImageData* data = static_cast<vtkImageData*>(outInfo->Get(vtkDataObject::DATA_OBJECT()));
#if VTK_MAJOR_VERSION >= 6
  this->AllocateOutputData(data, outInfo, extent);
#else
  this->AllocateOutputData(data, extent);
#endif

  data->GetPointData()->GetScalars()->SetName("NIFTI");

  const char* filename = nullptr;
  char* imgname = nullptr;

  if (this->FileNames)
  {
    vtkIdType n = this->FileNames->GetNumberOfValues();
    int headers = 0;
    for (vtkIdType i = 0; i < n; i++)
    {
      filename = this->FileNames->GetValue(i).c_str();
      // this checks for .hdr and .hdr.gz, case insensitive
      if (vtkNIFTIImageReader::CheckExtension(filename, ".hdr"))
      {
        headers++;
      }
      else
      {
        imgname = new char[strlen(filename) + 1];
        strcpy(imgname, filename);
      }
    }
    if (n != 2 || headers != 1)
    {
      vtkErrorMacro("There must be two files and one must be a .hdr file.");
      delete[] imgname;