[vtkusers] About coordinate system and vtkClipPolyData in VTK

[Jianlong Zhou]

hi, all,
I am now confused with coordinate system in VTK. 
I want to use the coordinate in the volume data to specify the 
implicit function used in vtkClipPolyData to clip volume as I 
expected. But how to know the coordinate of a point in volume data 
and what the corespondence relationship in display window? Dose 
anyone have any idea about this?

Thank you in advance.
JL