How can I make objects (not the whole screen) blurry?

[khvo100v]

Hello!

I am coding an experiment in Vizard. I want to present an object (e.g., a box) behind the semitransparent glass. To make it look more realistic, I want to make the edges of the object a bit blurry.
How can I do that? I found the Blur effects in Vizard documentation but it seems to me that they make the whole picture blurry, not specific places.

I would appreciate any help! I attached the toy version of my script with an object behind the glass. As you can see, the edges of the object have the same sharpness if you look at them directly or through the glass.


viz.setMultiSample(8)
viz.fov(60)
viz.go()
ground = viz.addChild('ground.osgb')
target = vizshape.addBox(size=[0.5,0.5,0.001], pos=[0,1.5,6])
filter_= vizshape.addQuad(size=[3.4,1.8],axis=vizshape.AXIS_Z,cullFace=False,alpha=0.5,eul er = [0,180,0],pos=[0,1.5,4],color=[0,0,1])