[vtkusers] How to use vtkGeoView/vtkGeoTerrain/vtkGeoSource

[Olli]

Hi,

I have a set of DEM files and should implement a multi-resolution terrain rendering solution. And ultimately place some 3D data objects to terrain view.

Because my data visualization already utilizes VTK, I'm looking for a solution that would use VTK also for terrain rendering. I took a look to vtkGeoView and vtkGeoTerrain classes, which already implement a multiresolution scheme. I just couldn't figure out how to get from DEM files to correct data representation. 

- How to process DEM files to get proper vtkGeoSource geometry tiles?  
- Do I manage with elevation data and color map only, or do I need some texture file to cover earth surface? 
- It is possible to use vtkGeoView and vtkGeoTerrain to render terrain for smaller areas than the whole globe? 
- And I'd like to render in planar projection, not spheric, as GeoView currently. Possible?

Some question to start with. I'm a bit confused...

Thanks,

Olli