I am working on a robotic simulator based on Blender.
I am using a small script  to generate terrain from aerial image and DEM .
Those two images are quite big (9000x9000) with a 5cm per pixel resolution.
My knowlwedge in modeling and mapping is quite limited, so I’m only using the displace modifier,
which limits me to a resolution of 50cm per pixel, and results in a model of 850K+ vertices and 1M+ tris .
My question is, is there a way to optimize the terrain using other methods (bump mapping / shaders) ?
I tried using the Decimate modifier, but it break the model (end up with a lot of holes in it).
 http://en.wikipedia.org/wiki/Digital_elevation_model (also referred as dtm or dsm in the code)
Thanks for your help!
Pierrick Koch - morse.openrobots.org