[vtkusers] lookuptable: rgb to 256 colors

[Marc Niethammer]

Hi,

I would like to create a vtkLookupTable with 256 colors which maps
arbitrary RGB values to a color that is close. I.e. I would need some
sort of equation that translates the r,g and b component to an index
in the colormap (lookuptable) which should then have an rgb entry that is
close to the one used for computing the index.

Does anyone know how to do this?

Thanks.

-- Marc