VTK 显示为 2D

void restrict_to_2d(QVTKOpenGLNativeWidget *widget) {
  // Set the render window's multisampling to 0.
  vtkRenderWindow *render_window = widget->renderWindow();
  render_window->SetMultiSamples(0);

  // Set the render window's stereo render to False.
  render_window->SetStereoRender(false);
}