Large Interiors

#1 Depends on a few factors. I think the question is hard to answer because it's open ended.

For the kind of engine Torque is, it can render quite larger interiors with good performance.

That being said I mean.. if a client PC is a junker or you overload your mission with things it will
effect performance. Each and every project needs to be tuned by the developer for performance
desired at the target computer level.

Also you didn't even say what engine so I just assumed 1.4 Torque by default.

#2 Yes I did mean 1.4, so thanks :)

#3 I think its better to make your large interior out of small interiors. Since you can use LOD on DIF and DTS files.

If you had one large interior and say you are sitting outside of it where you can see the whole thing. Even though BSP correctly determines what to render and what not to render. It would be even more efficient if the building was done in two or more sections (separate dif files) so that the farthest point in your screen would be rendered at low detail (assuming you are using LOD) even if it was visible. Now if the whole thing was one file, the engine would 1 have to parse the entire thing. 2 it would render anything visible at full detail even if it only takes 10 pixels of the screen.

Did i make sense? Correct me if im wrong.

Does BSP take into consideration the time it would take the player to get to an area?
I was thinking if the engine has to search the entire BSP tree on every frame to determine visibility, wouldnt it be more efficient if you can tell the engine that there is no way the player can get to point X in the next T seconds so dont bother checking that part of the tree in the next Z seconds. Wouldnt that make collision detection more efficient? Or if a rocket is fired and you know the velocity of the rocket, depending on the direction it was pointing, you should be able to determine the time it would take to get there and not check for collision until then. Obviously this idea needs some work or maybe its already implemented. Just thought id tell someone before i die. :)

#4 You would need to zone your interior and make sure that it fit within your mission boundaries. I would still recommend splitting it up into separate DIF's for management's sake (especially if the hallways can be reused). But a huge part of this also depends on your DTS decorations. Depending on the detail of your decorations, it might crawl of fly even if the interior itself renders wonderfully.

#5 Torque doesn't use BSP for visibility determination or rendering. It only uses hand placed portals/zone so the artist will have to construct the Interior properly. It does use BSP for collision though and the larger the Interior, the slower this will be (not appreciably slower but be aware that you will take a small hit).

Using multiple smaller Interiors will allow you to use LOD smartly and will help reduce the complexity of your having to create zones by hand.