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<DIV><FONT face=Arial size=2>Hello, everyone!</FONT></DIV>
<DIV><FONT face=Arial size=2>Suppose I have a polydata, which is consisted of
triangles, I'd like to get the faces which can be seen by the
camera.</FONT></DIV>
<DIV><FONT face=Arial size=2>That's to say, there is a point M, and an object
whose faces is a set of triangles, How can I get the faces that can be seen by
the point M? and how can I get the faces that is not seen by the point
M?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks!</FONT></DIV>
<DIV><FONT face=Arial size=2>Larry</FONT></DIV></BODY></HTML>