How to vary the transparency of the scene

[whj]

Hello,

<node3d>.alpha changes the transparency of an OBJECT. But I would like to vary the transparency of part of the SCENE. I tried creating a subview and subwindow, but that only makes part of the scene black.

The following is my code. Is there any way I can show, in the black area, the original scene but make it blurred?

import viz
viz.go()

viz.add('gallery.ive')

subView1 = viz.addView()
subWindow1 = viz.addWindow(pos=(0,1.0), size=(0.2,1.0))
corner of main window
subWindow1.setView(subView1)
subView1.setScene(2)

subView2 = viz.addView()
subWindow2 = viz.addWindow(pos=(0,1.0), size=(1.0,0.2))
subWindow2.setView(subView2)
subView2.setScene(3)

subView3 = viz.addView()
subWindow3 = viz.addWindow(pos=(0.8,1.0), size=(0.2,1.0))
subWindow3.setView(subView3)
subView3.setScene(4)

subView4 = viz.addView()
subWindow4 = viz.addWindow(pos=(0,0.2), size=(1.0,0.2))
subWindow4.setView(subView4)
subView4.setScene(5)

Thanks a lot,