I think there is a better way. After all, BSPs haven't changed much since Quake 1, and that was 1996! The supposed advantages of BSP were potential visibility culling, and fast line-tracing for collision detection. Nowadays, video cards can handle so many polygons that culling every little one you could is almost fruitless. As for the line tracing, it is really only a little bit useful. You still have to build an entire physics engine on top of just a simple line trace, which isn't very trivial, or even possible in some cases. I would suggest going with an arbitrary model format. Find one that fits your needs: make sure it supports the number of texture coordinates that you'll want to use (for normal mapping, for example), make sure the class structure makes sense to use in your design structure. Something as simple as OBJ formats, or ASE would work fine, or even 3DS. The next step would be to pick up a physics engine. I can't even begin to tell you how much work this saves you. Current physics engines handle *everything* for you, you can really just get down to programming the logic, once you get a framework in place. All of the major physics engines support arbitrary triangle meshes for the static environment, so it would be as simple as uploading the vertex/polygon data from your OBJ file to the physics engine, and all your collision detection and response is automatic.

Some physics engines that are highly used and praised (I could be wrong about licensing):
Newton - Free.
Novodex - Free, not free for commercial use.
ODE - Free, Open Source.
TrueAxis - New Comer. Free, not for commercial use though.

I personally use TrueAxis, it is the most wonderful piece of software currently in existence, in my opinion. I'm only a hobby developer, I'm not looking to make money off of my game, only hoping to maybe make a name for myself, so the license is just fine. Anyway, check it out!. If you want me to elaborate on anything, feel free to post here or send me a PM.

i agree with optus but i want to add somethings.

as optus did, i recommend the ASE format. u can push tons of raw data into it with no limit. on top of that it allows you to develop whatever data management you want. you can use the data to create BSPs, quadtrees, octrees, portals, anything. personally i would recommend using octrees. theyre soo basic its funny. it consists of dividing your entire world, inside of a bounding cube, and its divided into 8 parts. once along the x, y, and z axis'. this gives 8 cubes within the bounding cube. check the number of polys within each cube against a constant to see if further division is needed. its very similar to BSPs but instead of spliting into two parts, its split into 8 parts.

BSPs are a dying trend in the newer games.

Really you're only getting rid of BSP trees to replace them with another type of tree. Octree's are really popular like adam mentioned. Another is called a Quadtree (Can you guess? It just means 4 parts per cube instead of 8). Most of the physics engines I listed actually use an AABB tree. Which is, an Axis-Aligned Bounding Box, so tree traversal only consists of a simple bounds check. The BSP implementation with a single splitting plane per level is just old technology.