I keep running into a problem with maps, and I'm hoping for some comprehensive aid with it. The problem is lighting. Or more specifically, realistic interior lighting. That, as you can probably tell, is a mall. It is brightly lit, as you can likely also tell. This includes the ceilings, despite a lack of upward-facing light sources. When I attempt to do the same, I end up with a light source suspended in utter darkness. That, or I end up with a room blazingly lit to the point that I'm either going to get a tan or my monitor's going to have a nervous breakdown. I've tried using light_spot entities set up with a 90ยบ angle and high intensity. That doesn't help. I've tried using light entities- that tends to get me either garishly bright circles on the ceiling or nothing useful at all. I've tried using upward-facing light_spot entities, which largely duplicates the effect of the light entities. I've even tried using env_lightglow, which has resulted both in a slow snapping-on of all of the various entities after spawn and a ceiling obscured by enough flare I'd probably get the Attention Getter achievement if I tried playing a Pyro. In this particular case I'm trying to duplicate standard fluorescent lighting- which is to say a [ame=http://en.wikipedia.org/wiki/Dropped_ceiling]dropped ceiling[/ame] with periodically-placed lights inset into the ceiling.
http://developer.valvesoftware.com/wiki/Constant-Linear-Quadratic_Falloff Related are the 50%/0% falloff settings, which work in the same sense except you are manually defining two distances. http://forums.tf2maps.net/showthread.php?t=4949 see this too. Also make sure you have no leaks. Those will prevent light from bouncing. (pitch black ceilings with downward spotlights)