In-Game photoshop-esque effects Idea

[flame1396 9]

So I got an idea. I worry that it may be in the source code and I think that's a high probability.

However. Everyone knows of the great photoshop filters people put onto in game photos.

Would it be possible to emulate the nighttime color filter (makes the screen blue and darker) and have it make a city grayer in and out of gameplay. (to make it look like ShadowAssassins Ensenada filter, but in normal gameplay)

I bring this up because A) there seem to be a lot of these "filters", one for each stage of the sunset and one for night, and B) I *think* I saw a property pertaining to how dark the night gets in one of cycledoggs terrain controllers.

I worry it would require source code. But if it wouldnt, it would be very very cool.

PS: You could maybe turn it on and off like how you can choose night and day.