[vtkusers] Light on volums

[Giancarlo Amati]

Hello everybody,

I have the following problems with lighting: when I render my dataset as 
points, and I will move my camera position around the dataset (to simulate 
rotation, rolling and dolly) my points don't change color according to the 
light position (default light).
After that I visualize my poits as sphere glyph3d and when I move around 
my dataset, my sphere are colored in front of me, but they are black when 
I move behind them. I think that the reason is that exist a default light 
positioned at the original position camera, but how can I change that, I 
would like to see also the backface of my sphere.

Hoping to be clear, have a nice day!.

Giancarl

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dott. Giancarlo Amati                  |
(amati at ira.cnr.it)                     |
                                       |
National Research Council              |
RadioAstronomical Institute            |
office phone n. +39 051 6399405        |
via Gobetti 101 - Bologna (Italy)      |
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