[vtkusers] mapping floating image to color image using vtkImageMapToColors

[Rick Frank]

Hi,

I'm getting some behavior I don't understand when trying to map gray floating point image to a color image

What I'm seeing is that the output is completely white. 

my code is roughly as follows

filter->SetOutputFormatToRGBA()

colorTable->SetTableRange(0,1)
colorTable->SetHueRange(0,1);
colorTable->SetSaturationRange(0,1);
colorTable->SetValueRange(0,1);
colorTable->SetRampToLinear();

colorTable->ForceBuild();

Now, when I trace through the code, the values set in the RGBA image look correct. But the ultimate rendered image is completely white.

If I modify the code so that all the RGBA values are 1,0,0,255 the image is solid red. If I change the alpha to 64 nothing changes.

So, I suspect it's the mapper - I use the same mapper - vtkImageMapper to display the color image by resetting the input connection:

mapper->SetInputConnection(filter->GetOutputPort());
imageActor->SetMapper(mapper);

Do I need to make a change to the mapper to get the proper RGBA display?


Thanks

Rick