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<DIV><FONT face=Arial size=2>I am still new to VTK, and I was hoping someone
could clarify a simple question for me:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Imagine a simple pipeline A:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> polyReader ->
smoothFilter -> polyDataNormals -> polyMapper -> myActor ->
renderer</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>and I only do operations on the actor to adjust the
orientation and position of the model.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>A second pipeline B is identical, but with an
additional vtkThinPlateSplineTransform filter which is currently set up by
doing:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> tps =
new vtkThinPlateSplineTransform();<BR>
... </FONT></DIV>
<DIV><FONT face=Arial
size=2> <BR>
warpFilter = new
vtkTransformPolyDataFilter();<BR>
warpFilter.SetInput((vtkPolyData)myActor.GetMapper().GetInputAsDataSet());<BR></FONT></DIV>
<DIV><FONT face=Arial size=2>In 50% of circumstances, I do not need to use the
deformation of the thin plate spline transform, that is, its source and target
points will be identical. The only operations in this case will be the
aforementioned actor functions.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Q. Do I incur any extra cost of renderering time
because of the presence of the deformation filter, even though it is never
updated?</FONT></DIV>
<DIV><FONT face=Arial size=2>Q. If so, is there a way to enable/disable the
filter, without removing it from the pipeline, such that the cost is avoided,
and zero deformation is ensured?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Many thanks for your help everyone.</FONT></DIV>
<DIV><FONT face=Arial><FONT size=2>Greg</FONT></DIV></FONT></BODY></HTML>