I agree my terrain was perhaps not the best example but even very small hills could hide anything from a tank to a whole city depending on the view so could save some serious rendering time, especially if the occluder is only rendered when the player is near enough to it (i.e. if no occluders nearby then non are rendered and 0 time is lost)

With regards to generating a low poly occlusion mesh, when i threw that terrain together in max, a plane with a much lower resolution (10x10 as opposed to 50x50) was used with the same displacement map and slightly tweaked values...and it generated a really good mesh! BUT! because it was an organic mesh, not a plane or box, it either needed to be z sorted or drawn with a z-buffer... which would slow things down considerably. At the moment no z-buffer is used when drawing the occluders.

The same thing should also be able to work just fine indoors too, just grad the nearest few walls and use them. that way if you indoor level could be divided into chunks, whole segments could be disregarded pretty quickly..

Have put together a few other scenes, and will make 2 more demos on Monday and upload them, this time there will be some dynamic objects and a better test environment (I hope... two hills, a tunnel, a room*, and a building**)

** a box
* an open box

Thnx for all the resources!