vtkWindowToImageFilter fails on vtkBillboardTextActor3D
There are some problems when using vtkWindowToImageFilter to save an image of a render window which contains vtkBillboardTextActor3D objects.
- The text color is only visible in the image if the background opacity of the text is 1. Without background the text is always white.
- When using a scale > 1, the output of the vtkWindowToImageFilter does not contain any vtkBillboardTextActor3D objects.