Hi,<div><br>I've moved to vtkCellLocator, and it's working with no code changes or changes to initial parameters, so that in my opinion would suggest a bug with obbtree..... What are the relative merits of the two, vtkCellLocator and vtkModifiedBSPTree?</div>
<div><br>Andy<br><br><div class="gmail_quote">On 21 November 2012 11:28, David Doria <span dir="ltr"><<a href="mailto:daviddoria@gmail.com" target="_blank">daviddoria@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
On Wed, Nov 21, 2012 at 6:16 AM, Andrew Parker <span dir="ltr"><<a href="mailto:andy.john.parker@googlemail.com" target="_blank">andy.john.parker@googlemail.com</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
ation of t</blockquote></div><div><br></div>For line/mesh intersection I use vtkModifiedBSPTree:<div><br><div><a href="http://www.vtk.org/Wiki/VTK/Examples/Cxx/DataStructures/ModifiedBSPTree_IntersectWithLine" target="_blank">http://www.vtk.org/Wiki/VTK/Examples/Cxx/DataStructures/ModifiedBSPTree_IntersectWithLine</a><br clear="all">
<br>The way all of these line intersection algorithms works is that they actually intersect a finite line with the mesh. The 't' that gets returned is the relative distance along that line, so if the intersection occurs half way between the end points of the line segment, t would be 0.5. A t>1 seems to indicate that the length of the line segment you choose is too short, so that the line segment doesn't actually intersect the mesh between it's end points.<span class="HOEnZb"><font color="#888888"><br>
<br>David<br></font></span></div></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><p>__________________________________</p><p> Dr Andrew Parker</p><p> <a href="mailto:Em@il" target="_blank">Em@il</a>: <a href="mailto:andrew.parker@cantab.net" target="_blank">andrew.parker@cantab.net</a></p>
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