Dinamic LODing in BSPs

Ok, to start I mention BSPs but this method can be used in quad/oct-trees, so its not in any way restrictive. I had this idea while playing Return to Castle Wolfenstein, Multiplayer, the beach map. Basicly, much of the map can be seen from a small hill top in the beach. You can see the entire beach, the bunkers, the ocean, the players, etc, etc, etc... Now, from my position in that hill top, i would guess that the engine would have a lot to deal with, a lot of geometry to dump onto the graphics card. After doing basic occlusion using the BSP, and determining wich BSP leafs we have to draw, we could pass all of the visible geometry through a real-time LOD algorithm, to reduce the polygon count of map-meshes and player-meshes that are farther away. But then I had the idea of pre-processing some of that at the BSP compilation stage. Lets look at these two positions: [Hill Top] -> [Entire Beach] [Boat] -> [Small part of the beach] (->) means "i can see". Now, this is after the BSP has been compiled, but we are going to add a few stages to it still. For each leaf we compute the number of static (map) polys seen: [Hill Top] = 140k [Boat] = 32k Then, if that leafs'' visible polygon is above our threshold, we run a LOD algorithm on it, to reduce the number of polys, and for that we clone the visible leafs: [Entire Beach] => LOD Algo => [Entire Beach2] Lets check our polycount now: [Hill Top] = 55k [Boat] = 32k And the apearence of the BSP leaf structure: [Hill Top] -> [Entire Beach2] [Boat] -> [Small part of the beach] So, in other words, while at the Hill Top I''m no longer looking at the original beach geometry, but instead a 2nd LOD''ded version was created... This process makes sure that wherever we are in the map, the number of visible polys is allways under a certain pre-determined budget... I''m pretty sure other engines already do this, either in real time, or using pre-processed (BQO)SP trees.... What do you think?

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[Hugo Ferreira][Positronic Dreams][Colibri 3D Engine][Entropy HL2 MOD][My DevDiary]
[Yann L.][Enginuity] [Penny Arcade] [MSDN][VS RoadMap][Humus][BSPs][UGP][NeHe]
"our stupidity allways comes back to bite us in the ass... in a white-shark sort of way..." - Prozak