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<DIV><FONT size=2 face=Arial>Hi,</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>I would like to colour map complex scalars. This
could be the magnitude or the real part after multiplying the scalars by exp(i
theta) for a specified angle theta. </FONT><FONT size=2
face=Arial></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>I have written a class vtkLookupTableComplex
derived from vtkLookupTable. MapScalarsThroughTable2() does the conversion of
the real and imaginary components to a single value which is then mapped through
the table.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>This appears to work except when
InterpolateScalarsBeforeMapping is set on the mapper. In this case, the scalars
are mapped by <FONT
size=2>vtkScalarsToColorsPainter::MapScalarsToTexture().</FONT></FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>I am beginning to think a vtkDataSetAlgorithm based
solution would be easier but I need the performance for animating the scalars by
varying the angle theta from 0 - 360.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Should I give up or is there another
approach?</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Thanks for your time.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>John.</DIV></FONT></BODY></HTML>