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Hello K.R.,<br>
<br>
You can use a vtkVolumeTextureMapper2D, which should be significantly
faster than the ray caster. Also, you can use a vtkLODProp3D to combine a
couple of texture mappers (one with a reduced resolution volume) and a
ray caster so that you use a fast technique during interaction and fill
in with the more accurate technique during idle time. You can try out
VolView
(<a href="http://www.kitware.com/volview.htm" eudora="autourl">http://www.kitware.com/volview.htm</a>)
to see an example of this being done in an application. <br>
<br>
Lisa<br>
<br>
<br>
At 05:48 PM 4/13/00 -0400, K.R.Subramanian wrote:<br>
<blockquote type=cite cite> <br>
I would like to be able to display a density volume (single component
scalars) with varying opacity. <br>
Rather than doing ray casting - which is quite slow - is there a a
cheaper way to do this <br>
(on an SGI without 3D texture mapping capability)? For instance, we
have a spherical density field <br>
whose opacity is maximum at its center and decreases with radius. We
would like to visualize <br>
this as a transparent field. We tried building multiple iso-surfaces, but
the concentric rings look <br>
very much like 2D (with almost no shading). Teh application is to show an
object within this field <br>
and compute an integral of its intersection with teh field. <br>
<br>
-- krs <br>
<pre>--
K.R.Subramanian
Phone: (704) 547-4872
Department of Computer
Science
FAX: (704) 547-3516
UNC Charlotte, 228A Kennedy
9201 Univ. City
Blvd.
Email: krs@cs.uncc.edu
Charlotte, NC
28223-0001
WWW:
<a href="http://www.cs.uncc.edu/~krs">http://www.cs.uncc.edu/~krs</a></pre><font face="Courier New, Courier"></font>
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