[vtkusers] black box around volume

[Lisa Avila]

Hello Thomas,

Keep in mind that cells that have anything other than all 0's for the 
scalar values will have some opacity due to interpolation. I still suspect 
that you have non-zero opacity in a region with a dark color - try setting 
the color at scalar value 0 to something light - does this change your 
image? Also, you may wish to load your data into VolView (download here: 
http://www.kitware.com/products/volview.html) so that you can interactively 
explore it / change transfer functions / view scalar values.

Lisa


At 03:57 PM 6/1/2004, Thomas Faust wrote:

>I checked this, this wasn't the problem.
>
>-- snip --
>opacityTransferFunction->SetSegment( 1, 1.0, 255, 1.0 );
>opacityTransferFunction->ClampingOff();
>-- snip --
>
>In the area that appears black instead of white are only voxels with the 
>value
>0.0 (transparent).
>Some other ideas?
>
>
>On Tuesday 01 June 2004 02:50 pm, Lisa Avila wrote:
> > Hello Thomas,
> >
> > Look at your color / opacity transfer functions. There are some values in
> > your function that have a dark color and non-zero opacity, which is causing
> > the "black box".
> >
> > Lisa
> >
> > At 01:55 PM 6/1/2004, Thomas Faust wrote:
> > >I ran in a problem the other day.
> > >I'm working with a own implementation of VTK and QT and get strange visual
> > >effects.
> > >When I try to renderer a volume i get a black box around my model. (the
> > >background is set to white) This box moves with the model when I interact
> > >with it. (The extent of the box looks like the part the renderer redraws)
> > >
> > >Did anybody had same effects before?
> > >What could cause these effects?
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