Try vtkVisibleCellSelector. It can give you the cellIds of all of the visible cells. <br><br>It causes the renderer to enter a special mode in which each cell gets its own color, renders, readsback the pixel buffer, and spits out a list of the cells that were visible.
<br><br><div><span class="gmail_quote">On 3/7/07, <b class="gmail_sendername">Lim, Theodore</b> <<a href="mailto:T.Lim@hw.ac.uk">T.Lim@hw.ac.uk</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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<div dir="ltr"><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">Hello
everybody.</span></font></div></div>
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<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font> </p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">Is there a way to query the renderer
for the cells and its associated colors being rendered? </span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font> </p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">I would like to extract the cell IDs
and its color that is visible at any given camera orientation and
position.</span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font> </p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">It's something like
as</span></font><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">king the graphics board which pixels
(and color) is being displayed. </span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font> </p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">I'm not sure if this can be done via
the vtk classes available. Would appreciate if anyone can point me in the right
direction.</span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font> </p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">Thanks in advance,</span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;">Theo.</span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font> </p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;"></span></font> </p></div></div>
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