Add ability to take screenshots mid python Data/Custom Transform

[jtschwar]

Is your feature request related to a problem? Please describe. Hi, I would like a command that could take screenshots of my live-tomography reconstructions after each iteration. I know that paraview has this function in its simple module. This feature works whenever I try to run it in the python consule but will cause toviz to crash when I try to run these lines of code as a python transform:

from paraview import simple

# view and camera objects view = simple.GetRenderView() cam = view.GetActiveCamera()

fname = imageDirectory + format(index,"02d")+".png" simple.SaveScreenshot(fname,view, ImageResolution=(1024,1024))

If possible, I would love for this feature (or a variation of it) to be integrated into tomviz so that I could record images during these iterative processes.