[vtkusers] Level of detail for image data

[Roger Blum]

Hi all,

I would like to display maps of different resolution
- overview 1:1000000 (1 tiff file)
- middle     1: 500000 (1 tiff file)
- detail       1: 100000 (10 tiff files -> tiles)

How can I make vtk automatically change the used resolution (depending on 
zoom)?

My idea is to have a pipeline as follows:
- A vtkTiffReader for each map file attached to a vtkImageMapper
- A vtkLODActor to which I connect all the vtkImageMappers

Does this work with 2D images (the maps)? How does the vtkLODActor know, 
when to switch resolution? Do I have to provide this information? If yes, 
how?

Is there another way of achieving the desired behavior? E.g by controlling 
the zoom level and turning on/off the visibility of the actors?

Any hint or idea is very much appreciated!

Roger