Model buildings complete or in segments

[DragonSpawn]

So if I want to make a building for my game (outside of the UDK editor) what is the most performance efficient method?
If I make the building as one object then I would probably have to export it as a skeletal mesh so I can add the collision objects to it, which I assume might be CPU intensive.
And then of course I could make my building in segments (doorway, stairs, wall segment, etc) and then puzzle them together in UDK as static meshes.

Which scenario would generate most performance you think? Especially if you think of large apartment buildings and such. Less draw calls with large objects, more instancing with segment objects and more efficient culling.

[Xendance]

Segments are the way to go. That way you can reduce memory usage by using the same static mesh over and over (like a wall piece, door etc), also the engine can then cull everything that isn't on the screen. If you make a big building as one model, the engine has to drawn that whole building even if you only see a corner of it.

http://udn.epicgames.com/Three/ModularLevelDesign.html

[nfollmer]

Segments are the way to go. That way you can reduce memory usage by using the same static mesh over and over (like a wall piece, door etc), also the engine can then cull everything that isn't on the screen. If you make a big building as one model, the engine has to drawn that whole building even if you only see a corner of it.

Exactly, what I do is model my entire building in MAX, then cut it up (just so I know when it hits the editor, the pieces will fix together without seams). Another tip, make sure you're piece sizes are multiples of 4, that way they snap perfectly ;)

[Xendance]

Yes, and as the the guy in the .pdf file says, always have the grid snap on when doing modular pieces.

[PuckerFactor]

also...if you have a tall building and you look up... you want the LOD's to load a lower res mesh/texture for the top sections than the bottom....vice-versa if you are looking down from a building.

[micahpharoh]

just an fyi, usually you should set collision on meshes to only block physics and weapons, then put blocking volumes over the meshes. This will further optimize the meshes. If you look at the maps that are in the game they do this for everything.

[CyborgGuineaPig]

just an fyi, usually you should set collision on meshes to only block physics and weapons, then put blocking volumes over the meshes. This will further optimize the meshes. If you look at the maps that are in the game they do this for everything.

Hah oh man, this could have been so useful in production.

[Nawrot]

Those blocking volumes were put more because of gameplay than optimization. It is really annoying when you fighting to get stuck on some tiny detail. So they smoothed walls with volumes.

[IWillShutUDown]

how do you copy and move the whole building

[GRoss]

So do the building parts look like separate objects in the editor or do they look and are interacted with (move, rotate, scale) as 1 object or many, because when I export my objects that make up 1 building from blender, they all seem to merge together to form 1 single object...

[Norman3D]

FYI guys: Lots of pieces are not good either. Actor count will increase, so you have to be careful. Try to make big chunks, but that have not much triangles. If they do have too much, slice them into different ones.
It also really depends... Is it a building you are going to fully access, then yeah, probably a lot of actores will do the job, or is it a background building? In that case, a single, low res mesh will be enough. Sometimes it's a combination... Maybe you can only get close to the first story of the building, focus on that, and make all the others 1, 2, maybe 3 staticmeshes, but very low res ones.
My point is, that, it's not always good to have everything super sliced, meaning detailed, if it's not in the players path. Save the actor count for something else, and make a low res version, less sliced, instead.