This is really best addressed as a number of semi-related building tips:

      Plan Ahead. If you know you want buildings in your map, plan their locations from the first. Very complicated buildings (lots of geometry and surface detail) should be isolated away from long views. One reason for this is to control in view polygon counts. The second (and really obscure one) is to reduce the amount of z-compression that will affect the structures.

      Build to Support Game play. Each of the structures in the Q3:TA terrain maps was built to support a game play need. Quite often, less is better than more.

      Build Simply. Simple, uncomplicated architecture may be best. The more complicated you make your buildings, the less complicated the terrain around them can be. Depends on what you want to play up. The busy look of many Q3A maps doesn’t translate well to large terrain. Details are lost at great distances and only add to the triangle complexity of maps containing them.

      Detail Content. With few exceptions ALL the geometry inside the terrain map is detail content, not just the terrain entity. The walls forming the corridor in mpterra2 may be the only non-detail structures in that map. Making geometry into detail makes a map far easier and faster to compile. If you want to block vis inside your structures, create simple caulk structures … much the same way as described for vis blocking the terrain.

      Z-Compression Problems. Review the the map in 16 bit mode during development. This brings out z-fighting issues that occur at long distances. This z-fighting is created by detail brushes being compressed into each other (The Q3A engine does a significant amount of “z compression” as geometry becomes farther away from the viewer). This z-compression is far less apparent in 32 bit modes, but we have to remember that many people turn down graphic features in order to simply play Q3A on their systems (not just to get ridiculously high frame rates).

      Fit Structures to the Terrain. Don’t just set structures on terrain and expect them to look right. Make your buildings look like they belong where you put them. Accommodate the rise and fall of terrain in your floor plans … or “dig” into the terrain brushes to create basements, tunnels and whatever you need. You can also adjust the height map to better arrange the geometry around structures, or manually tweak the triangles once the structures are in place. History is full of examples of really interesting buildings that have been built to accommodate difficult terrain like hills, cliffs and mountains.