Hi Rachel,<div><br></div><div>If your data is a polydata, then you should use vtkCellLocator's IntersectWithLine() method.</div><div><br></div><div>locator->SetDataSet(data);</div><div>locator->BuildLocator();</div>
<div><br>Then, you need to create a line segment where one end is at the center of the pixel, and the other end is some large distance away in the direction of the silhouette plane normal:</div><div><br></div><div>n = silhouette plane normal</div>
<div>p1 = pixel location</div><div>p2 = p1 + d*n where d is approximately twice the distance from the silhouette to the 3D object</div><div><br></div><div>locator->IntersectWithLine(p1, p2, tolerance, t, x, pcoords, subId, cellId);</div>
<div><br></div><div>The IntersectWithLine method gives you "x" which is the position you want, and it also gives you a lot of information you don't need like parametric coordinates, the cell ID, and the sub ID. Look at the vtkAbstractCellLocator documentation for more info on IntersectWithLine.</div>
<div><br></div><div> David</div><div><br></div><div><br></div>
<div><br></div><div><br><div class="gmail_quote">On Wed, Dec 15, 2010 at 11:36 AM, Rachel <span dir="ltr"><<a href="mailto:aracha2010@gmail.com" target="_blank">aracha2010@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br>
I got the 2D silhouette of 3D object. Then given a pixel i want to find it<br>
corresponding 3D point.<br>
<br>
Any help please<br>
Thanks<br>
--<br>
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