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<p class=MsoNormal><font size=2 color=maroon face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:maroon'>I don’t
think deforming the mesh by changing the point coordinates will “wreak
major havoc” with the Pipeline. The point coordinates have no
effect on ghost cells. Ghost cells are determined by connectivity, which
still cannot be changed by the array calculator. I’m pretty sure
the pipeline will automatically recompute the geometric bounds of the data as
necessary. And although it is true that changing point coordinates will
invalidate normals, the same is true for any filter that modifies the geometry.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=maroon face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:maroon'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=maroon face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:maroon'>Overall, the behavior
would not be much different than any of the warp filters. True, it would
not be hard to create a bizarre or invalid output, but VTK provides many easier
and more spectacular ways to shoot yourself in the foot.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=maroon face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:maroon'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=maroon face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:maroon'>-Ken<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=maroon face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:maroon'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
vtk-developers-bounces+kmorel=sandia.gov@vtk.org
[mailto:vtk-developers-bounces+kmorel=sandia.gov@vtk.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Randall Hand<br>
<b><span style='font-weight:bold'>Sent:</span></b> Monday, August 28, 2006 3:11
PM<br>
<b><span style='font-weight:bold'>To:</span></b> Clinton Stimpson<br>
<b><span style='font-weight:bold'>Cc:</span></b> vtk-developers<br>
<b><span style='font-weight:bold'>Subject:</span></b> Re: [vtk-developers]
vtkArrayCalculator enhancement</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>Sounds intruiging.
I previously toyed with the idea of adding the ability to use a point's
location in the formula but never implemented it. In my case I needed to
compute a cartesian vector's cylindrical R component for an isosurface
extraction (radial field strength). I wound up just doing it manually. <br>
<br>
But allowing the user to "deform" the mesh through the Array
Calculator... I'm not an expert here, but won't that wreak major havoc with the
vtk Pipeline (Ghost Cells, normals, range/extents)?<o:p></o:p></span></font></p>
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<p class=MsoNormal><span class=gmailquote><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>On 8/28/06, <b><span style='font-weight:bold'>Clinton
Stimpson</span></b> <<a href="mailto:clinton@elemtech.com">clinton@elemtech.com</a>>
wrote:</span></font></span><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Just thought I'd let others know...<br>
<br>
I'm enhancing vtkArrayCalculator so that it can compute on point<br>
coordinates as well as scalars and vectors.<br>
And also have an option to output results as coordinates.<br>
I hear I'm not the only one that wanted this. <br>
<br>
I'll wait a few days till the dashboard clears up, of course.<br>
<br>
Clint<br>
<br>
_______________________________________________<br>
vtk-developers mailing list<br>
<a href="mailto:vtk-developers@vtk.org">vtk-developers@vtk.org </a><br>
<a href="http://www.vtk.org/mailman/listinfo/vtk-developers">http://www.vtk.org/mailman/listinfo/vtk-developers</a><o:p></o:p></span></font></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><br>
<br clear=all>
<br>
-- <br>
----------------------------------------<br>
Randall Hand<br>
Visualization Scientist<br>
ERDC MSRC-ITL <o:p></o:p></span></font></p>
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