[vtkusers] transparent 3D over 2D

[David Gobbi]

Are you using depth peeling?  Depth peeling disables alpha, it is an
alternate strategy to translucent rendering that doesn't use alpha and
as far as I understand, it actually requires alpha-blending to turned
off in order to work.

So I don't think that depth peeling can be used when an underlay is
present (or at least, not in VTK).

 - David


On Fri, Jul 8, 2011 at 10:32 AM, Chris Volpe ARA/SED <cvolpe at ara.com> wrote:
> I’m rendering 3D geometry over a 2D image drawn onto the rendering window
> using an Actor2D. The 3D geometry  is semi transparent, as can be seen when
> some 3D geometry is drawn on top of other 3D geometry. However, the
> transparency does not permit seeing the background image through the 3D
> geometry. For purposes of the background image, the 3D geometry is
> completely opaque. Is this an inherent limitation, or am I doing something
> wrong?
>
>
>
> Thanks,
>
>
>
> Chris
>
> --
> Christopher R. Volpe,
> Ph.D.                                                           Email:
> cvolpe at ara.com
>
> Senior Scientist, Information Exploitation Systems             Main Desk:
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>
> Applied Research Associates,
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>
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