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<div>The typical way this type of testing is done within the VTK regression tests is to run your algorithm, render the result, and then test the image to some ground truth image. There is a utility in VTK (vtkRegressionTestImage) that performs this test with
the requisite tolerance to compensate for slight variations in hardware (as well as the ability to provide multiple ground truth images for instances where the difference is more than a little but still correct).</div>
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<div>There are lots of examples in the VTK source. A basic one is called Mace.cxx. Take a look at that example first.</div>
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<div>-Ken</div>
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<span style="font-weight:bold">From: </span><Kilgus>, Thomas <<a href="mailto:t.kilgus@Dkfz-Heidelberg.de">t.kilgus@Dkfz-Heidelberg.de</a>><br>
<span style="font-weight:bold">Date: </span>Thursday, January 24, 2013 3:32 AM<br>
<span style="font-weight:bold">To: </span>"<a href="mailto:vtk-developers@vtk.org">vtk-developers@vtk.org</a>" <<a href="mailto:vtk-developers@vtk.org">vtk-developers@vtk.org</a>><br>
<span style="font-weight:bold">Subject: </span>[EXTERNAL] [vtk-developers] How can I test my PolyData Algorithm? #2<br>
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<p class="MsoNormal"><span lang="EN-US">Hi there,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I didn’t get any answer last time (also on the user’s list) so I try again
</span><span lang="EN-US" style="font-family:Wingdings">J</span><span lang="EN-US">:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I have an algorithm generating a vtkPolyData as output. I would like to write a test, in order to make sure that my algorithm generates the same output every day (even though there might be changes to the algorithm or
to surrounding classes). What is a nice way to do this?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I thought I could save a generated PolyData as “ground truth” and compare it point wise to the generated output. However, my output data contains lots of 3D floating-point points and thus I have to perform lots of comparisons
between floating-point numbers and this can be difficult for different data or 32Bit/64Bit Systems.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I was wondering if there are any methods/classes already meant general testing purposes? Anything I could reuse for comparing two PolyDatas or anything to make sure my algorithm provides the same result for the same data.
I tried to look into tests of other VTK classes but couldn’t really find anything. Any suggestions?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thomas<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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