It's best to optimize so that your outdoor levels are under 120k polys at all times. this is because enemies will slow it down if there's more than that. here are some screens I have, and examples of the techniques I use in my outdoor designs.
imageflock.com/img/1320803448.jpg[/img]
1. note that most buildings are tall and basic cubes. this is very helpful in keeping polycount down, and creating scenery. to subtract from the level's boxyness, some of them have illuminationmaps to create more detail.
2. most detail is up high, using the sky as a backdrop, it looks nice.
3. the larger square buildings hate AI, so I used segments as their bases, and made sure to put entrances, as they create a more convincing atmosphere. never do I lapse into putting random crates in the road and whatnot.
4. contrasted lighting crowds the player's eye and effectively double's the look of detail. another example of contrasted lighting effectively creating detail-
5. I use smaller buildings and billboards behind the stuff the player can walk to. this creates a forced perspective effect.
max polycount in this scene- 130k with enemies spawned and active.
==================
imageflock.com/img/1312261172.jpg[/img]
some tips on another technique, fake terrain.
1. use shadowy ground textures with lots of differing colour. it looks slightly hilly.
2. note that this level appears to slope down from left to right? it's because of the general path through the map, as well as the placement of the buildings. the ground is flat to save polys, but the player goes from the roofs to the ground, and in that it gives the false sense of going down a mountain. in reality I just move things lower as they go, but the ground only descends one segment.
the polycount in that screen is (I'm not sure not being near fpsc but I remember it being like 110k with enemies)
