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<p class="MsoNormal">Pat<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Very useful. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">One suggestion. Where you write <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">“</span>Oops, not so colorful anymore. The color is interpolated between the vertices, and the result doesn't look anything like the color map. The same effect
occurs for wireframe visualization too:”<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I think you should add something like “It’s important to notice that when InterpolateScalarsBeforeMapping is off, the colours are interpolated using the opengl vertex RGB values and this can lead to the appearance of colours in your visualization
which <b><i>do not appear at all</i></b> in your original colour map. (This is because the 2D interpolation in RGB space between vertices will not follow the same path as the interpolation along the 1D colour map)”<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It’s obvious from the pictures what’s going on, but I suspect that some people will not quite appreciate some of the subtle implications and some extra text might help.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">$0.02<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">JB<span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:36.0pt"><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span lang="EN-US" style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> vtk-developers-bounces@vtk.org [mailto:vtk-developers-bounces@vtk.org]
<b>On Behalf Of </b>Pat Marion<br>
<b>Sent:</b> 01 December 2012 03:35<br>
<b>To:</b> vtkdev; Communications<br>
<b>Subject:</b> [vtk-developers] interpolate scalars blog post<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt">I was recently explaining <a href="http://www.vtk.org/doc/nightly/html/classvtkMapper.html#a9e0262837bb18752277a6a9c7b972583">
InterpolateScalarsBeforeMapping</a> to someone, and decided it would be useful to have a visual aid, so I wrote a blog post.<br>
<br>
<a href="http://www.kitware.com/blog/home/post/414">http://www.kitware.com/blog/home/post/414</a><br>
<br>
Comments, and typo / factual corrections are appreciated, thanks!<br>
<br>
Pat <o:p></o:p></p>
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