Hi
I love Unity but can a Unity developer just cover why the engine does NOT use BSP or PVS for speed.
I know BSP may not work with Unity because it needs convex sets, but why not one of the other scene management systems?
Plus why does Unity not use a LOD out of the box?
The reason I ask is that other engines in Unity’s class and up to very high end engines use these scene management.
BSP is useful for limited situations (most indoor corridor shooters). What use does BSP have for an outdoors game? For a puzzle game? For a top down RTS game? For a poker game?
That said, yes, some sort of occlusion culling system would be useful to have, in case you’re making an indoor game with lots of occlusion. We have PVS in Unity iPhone, but that is not integrated in main Unity yet (coming at… some point).
Likewise with LOD - Unity is not targeted at any particular game/graphics genre. LOD techniques are well developed for classic first/third person games, but for lots of other game types, they are inefficient or just useless. You can do manual LOD for models pretty easily from scripts (setup multiple mesh versions, swap them based on distance). Unity does have built-in LOD for terrains though.
PVS from unity iPhone to regular flavour unity will be nice to have. LOD however I think it another matter - Aras already covered most of it and considering how easy it is to implement on your own, I don’t think it would be desirable to have the unity devs put their time into it (in stead of all the other cool stuff they could be working on).
We should get an LOD example on the wiki though. /me notes that for later review.
My project will have both indoor and outdoor scenes, so I would be very interested in a PVS implementation.