I want to do this because when you slice a vtkpolydata representing a volume, depending on the quality of the model, the resulting slices are not always closed.<br>I rely on heuristics to close them but I just saw this page that say that, by using a BSP tree, the result of the slicing operation is guaranteed to be closed.<br>
<br><a href="http://www.me.mtu.edu/~rmdsouza/CSG_BSP.html">http://www.me.mtu.edu/~rmdsouza/CSG_BSP.html</a><br><br>I just want to know if it's possible to make it with vtk classes. <br><br>--<br>Eddy<br><br><div class="gmail_quote">
2012/3/22 Biddiscombe, John A. <span dir="ltr"><<a href="mailto:biddisco@cscs.ch">biddisco@cscs.ch</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">erratum. I should have written “to add an intersect with plane” – not line.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">seeing the question again, you ask about vtkCutter, so in theory you might want any ImplicitFunction. The same argument applies, but the implementation become
slightly more involved as you would have to test each box against the function and not against a simple plane.<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">JB<u></u><u></u></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"" lang="EN-US">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"" lang="EN-US"> <a href="mailto:vtkusers-bounces@vtk.org" target="_blank">vtkusers-bounces@vtk.org</a> [mailto:<a href="mailto:vtkusers-bounces@vtk.org" target="_blank">vtkusers-bounces@vtk.org</a>]
<b>On Behalf Of </b>Biddiscombe, John A.<br>
<b>Sent:</b> 21 March 2012 17:12<br>
<b>To:</b> edd cmaugo; <a href="mailto:vtkusers@vtk.org" target="_blank">vtkusers@vtk.org</a><br>
<b>Subject:</b> Re: [vtkusers] vtkModifiedBSPTree slicing<u></u><u></u></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1f497d" lang="EN-US">></span></b>Is it possible to slice a vtkModifiedBSPTree with a vtkCutter ?<span style="color:#1f497d"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Not without code changes. Why would you do this? You can slice a vtkDataSet with a cutter and that will give you much the same result.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Do you have data already in the BSP tree? and you want to cut it faster?<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">If the answer is yes to both, then look at the BSP tree intersect with line code. I think in my local repo I may have an intersect with Box function too. To
add an intersect with line, you need only walk the tree using the stack in the same way as the existing code, test each bounding box against the slice plane and reject any on the wrong side. open those that overlap and then keep going until you get to cells.
Then you can call vtkCell intersect/slice or whatever.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">It would be quite simple to implement if you examine the existing code.<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">JB<u></u><u></u></span></p>
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