itk-vtk-viewer - CLI - Data types

If I run itk-vtk-viewer from the command line (as per Command Line Interface | itk-vtk-viewer) I can drag data sources in and visualise.

This is a two part question

  1. What are the data types that can be dragged and dropped here. Have tried .nrrd and .vti as examples and they work. Is there a full list?

  2. In an application, I am visualising data currently using itkwidgets which uses itk-vtk-viewer to visualise vtk.vtkGlyph3D()
    i.e. along the lines of

glyphs = vtk.vtkGlyph3D()
glyphs.SetInputData(data) # Data is of type polydata


How can I save this data so that I can drag it into this CLI version of the itk-vtk-viewer similarly to how I can drag in an .rnnd file?