[vtkusers] vtkLookupTable Transpacency == background color?

[Chris Want]

John Biddiscombe wrote:
 > Its been a while since I played with this, but isn't the call to
 > Build unnecessary. If you call Build it'll build it'll overwite the
 > values from its own computation (based on HSV values). If you stuff
 > data in yourself, then don't call it.
 >
 > JB

Hi John,

Thank you for your insight -- you are indeed correct:
the call to lut.Build() was unnecessary.

Unfortunately removing this call did not fix my problem
-- the areas that are supposed to be transparent are
still colored with the renderer's background color.

Thanks again,

Chris Want
Research Computing Support
Computing & Network Services
University of Alberta
Tel: 1-780-492-9418