Light level

Is there a way for a SENT to determine how bright an area is? For example, say I’m building a solar panel SENT (which I am, actually). I would need the panel to figure out how much energy to produce based on how bright a particular area is.

You can’t, the closest thing you can do is use render.GetLightColor(pos) and attempt to convert it into a usable value. The best you can do is make a “sun” position and see if there is a clear LOS to it.
(Line of sight).

I don’t think the source engine is capable of doing that sort of thing on demand.

There’s a night vision script that can auto activate depending on the light level of the area your in