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<DIV><FONT face="Bookman Old Style">Hi,</FONT></DIV>
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<DIV><FONT face="Bookman Old Style">I want to pick a point of volume from
screen. The vtkPointPicker is used to select a point by shooting a ray into a
graphics window and intersecting with actor's defining geometry - specifically
its points. However this method cannot select a point, which I see on screen.
For example, I have a MRI series of head and I can visualize its
internal organ,e.g. brain, by adjusting opacity function. I select a point on
the brain surface with mouse, but the return point of vtkPointPicker is that
located on the boundary box of the volume. How to select a point of the volume,
which I can see on the screen?</FONT></DIV>
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<DIV><FONT face="Bookman Old Style">Regards,</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">Yixun Liu</FONT></DIV></BODY></HTML>