[vtkusers] getting pointids from an imagedata

[Matthias Zangl]

Hello!

I am displaying a volume (vtkImageData) - slice by slice on my screen. I
realized it by changing the outputorigin on slicing. Well, that works well
so far. Now I want to get the pointid from a point the user is selecting on
the screen. All I got are the coordinates in the renderwindow. I suppose
I've to take care that they 're calculated dependend on the resolution and
current zoomfactor of my image. Maybe someone have some hints for me.

greatly appreciated,

bye,
Matt