[vtkusers] vtkFixedPointVolumeRayCastMapper - Space between Planes

[David Christen]

How can I change the gap between the planes that 
vtkFixedPointVolumeRayCastMapper creates?

In my Data (vtkImageData) the spacing is usually around 0.032 mm.

The resolution in x and y direction is okay, but in z-direction the 
resolution is very poor. Only about 3 planes are computed.

AutoAdjustSampleDistancesOn() seems to affect only the resolution in x 
and y direction.

I can't find the appropriate function. It should be easy to do, because 
the output is perfect when I set the spacing of my data to 1.0

thank you in advance