by Thorsten » Thu Apr 05, 2018 11:00 am
Memory usage (as long as memory isn't full and the machine goes into swap) usually does not cause framerate loss.
If there are 'many' objects in the scene (like for OSM2City), the thing that helps a lot with faster rendering is merging them together so that they can be done in one draw (this however makes scenery database management awkward, so outside OSM2City it is not encouraged).
Designing your 3d models properly to avoid unnecessary draws is likely to be more effective than worrying about their total number.
In general, go ahead and populate an airport as much as you enjoy - if that's too much for a user, there's still ~19.999 other airports in the world which are near empty and can be used instead - and time is with you, in two years from now computers will be faster again.