[vtkusers] strange vtkLookupTable problem.

[Luca Pamparana]

Hi everyone,

I am constructing a vtkLookupTable manually as follows:

double * range = reader->GetOutput()->GetScalarRange();
vtkLookupTable * greenMap = vtkLookupTable::New();
greenMap->SetNumberOfTableValues(256);
greenMap->Build();

double i = 0.0;

for(int index=0;index<256;index++)
{
     greenMap->SetTableValue(index, 0.0, i/256.0, 0.0, 1.0);
      i++;
}
greenMap->SetAlphaRange(1.0,1.0);

greenMap->SetTableRange(range[0], range[1]);
colorMapper->SetLookupTable(greenMap);
colorMapper->Update();


I see nothing but a black screen. However, when I generate the table for
red... like:

redMap->SetTableValue(index,  i/256.0, 0.0, 0.0, 1.0);

then my image is mapped correctly to red values...

It is weird...red and gray color maps work but not green and blue!!

Can someone help me find what the problem is...it is driving me nuts!

Thanks,

Luca
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