@Override
 public void prepareForSerialization() {
   super.prepareForSerialization();
   projectionMatrix = null;
   volStride = null;
   volumePointer = null;
   projectionArray = null;
   projections = null;
   projectionsAvailable = null;
   projectionsDone = null;
   cuCtx = null;
   gridSize = null;
   projectionTex = null;
   h_volume = null;
   initialized = false;
   function = null;
   module = null;
 }
  @Override
  public void prepareForSerialization() {
    super.prepareForSerialization();
    projectionMatrix = null;
    volStride = null;
    volumePointer = null;
    projectionArray = null;
    projections = null;
    projectionsAvailable = null;
    projectionsDone = null;
    h_volume = null;
    initialized = false;

    // JOCL members
    program = null;
    device = null;
    kernelFunction = null;
    commandQueue = null;
    projectionTex = null;
    context = null;
  }