<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Thanks David for the reply. How can I create a mesh from cloud points. I would like to have a mesh to have more accurate result.<br><br>Thanks,<br>Sara<br><br>--- On <b>Tue, 11/10/09, David Doria <i><daviddoria+vtk@gmail.com></i></b> wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"><br>From: David Doria <daviddoria+vtk@gmail.com><br>Subject: Re: [vtkusers] extract curvatures from cloud points<br>To: <br>Cc: vtkusers@vtk.org<br>Date: Tuesday, November 10, 2009, 1:15 AM<br><br><div id="yiv822638869"><div class="gmail_quote">On Mon, Nov 9, 2009 at 4:29 PM, sara shafaei <span dir="ltr"><<a rel="nofollow" ymailto="mailto:sara_shafaei@yahoo.com" target="_blank" href="/mc/compose?to=sara_shafaei@yahoo.com">sara_shafaei@yahoo.com</a>></span> wrote:<br><blockquote class="gmail_quote"
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Hey Guys,<br><br>I am trying to extract curvatures from cloud points. I converted the cloud points to vtkpolydata format but vtkcurvatures didn't accept it, so I tried to use vtkTriangleFilter before vtkcurvature. it doesn't also accept vtkpolydata and vtkDelauny3D output. Any help would be appricited.<br>
<br>Thank you,<br>Sara <br></td></tr></tbody></table></blockquote><div><br>You need to create a mesh from the points before you can use the vtkCurvatures filter. This is typically not very easy to do. You may want to look at using some local information on the point cloud to estimate an indicator of the curvature - something like for each point:<br>
1) find all points in some specified radius<br>2) fit a plane through those points<br>3) compute the average distance of all the points in the radius to the plane<br><br>This will give you a reasonable sense if the point is on a flat surface or a non-flat surface.<br>
<br>Does this sound like a reasonable approach to anyone else? Should I make a vtkPointCloudCurvatureEstimation class?<br><br clear="all">Thanks,<br><br>David <br></div></div>
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