[Robotics] Depth information from a camera

[Gilberto Echeverria]

Hello everyone,

For the MORSE simulator, we are trying to recreate laser range scanners, 
that provide depth information from a sensor on a robot. We are 
currently doing this using ray tracing, but if we want to simulate 
sensor with a lot of lasers, I fear ray tracing all of them will be too 
slow.
So my question is: Is there a way to get the depth information of a 
scene in a faster way? We need something that can be used from the Game 
Engine of Blender 2.5
One possible method is to get the z-buffer from a camera. Apparently 
this was possible in Blender 2.49, using the BGL modules, but that seems 
to have disappeared from Blender 2.5.

Any ideas will be greatly appreciated.
Cheers

Gilberto