Method Write

IO/Export/vtkJSONDataSetWriter.cxx:182–295

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

//------------------------------------------------------------------------------
void vtkJSONDataSetWriter::Write(vtkDataSet* dataset)
{
  vtkImageData* imageData = vtkImageData::SafeDownCast(dataset);
  vtkPolyData* polyData = vtkPolyData::SafeDownCast(dataset);
  this->ValidDataSet = false;

  // Get input and check data
  if (dataset == nullptr)
  {
    vtkErrorMacro(<< "No data to write!");
    return;
  }

  // Capture vtkDataSet definition
  std::stringstream metaJsonFile;
  metaJsonFile << "{\n";
  metaJsonFile << "  \"vtkClass\": \"" << dataset->GetClassName() << "\"";

  // ImageData
  if (imageData)
  {
    this->ValidDataSet = true;

    // Spacing
    metaJsonFile << ",\n  \"spacing\": [" << imageData->GetSpacing()[0] << ", "
                 << imageData->GetSpacing()[1] << ", " << imageData->GetSpacing()[2] << "]";

    // Origin
    metaJsonFile << ",\n  \"origin\": [" << imageData->GetOrigin()[0] << ", "
                 << imageData->GetOrigin()[1] << ", " << imageData->GetOrigin()[2] << "]";

    // Extent
    metaJsonFile << ",\n  \"extent\": [" << imageData->GetExtent()[0] << ", "
                 << imageData->GetExtent()[1] << ", " << imageData->GetExtent()[2] << ", "
                 << imageData->GetExtent()[3] << ", " << imageData->GetExtent()[4] << ", "
                 << imageData->GetExtent()[5] << "]";

    // Direction
    // Write the matrix using vtk.js convention for direction matrices (transpose the matrix)
    auto direction = imageData->GetDirectionMatrix()->GetData();
    metaJsonFile << ",\n  \"direction\": [" << direction[0] << ", " << direction[3] << ", "
                 << direction[6] << ", " << direction[1] << ", " << direction[4] << ", "
                 << direction[7] << ", " << direction[2] << ", " << direction[5] << ", "
                 << direction[8] << "]";
  }

  // PolyData
  if (polyData && polyData->GetPoints())
  {
    this->ValidDataSet = true;

    vtkPoints* points = polyData->GetPoints();
    metaJsonFile << ",\n  \"points\": "
                 << this->WriteArray(points->GetData(), "vtkPoints", "points");

    // Verts
    vtkNew<vtkIdTypeArray> cells;
    polyData->GetVerts()->ExportLegacyFormat(cells);