Peculiarities

Real-world lighting can be either an additive or a subtractive process. In a dark studio, you add lights one-by-one to build up the image to what you’re trying to achieve. If you’re outside, you do a lot of subtractive lighting to add contrast back, like adding large black flags next to actors to shadow their faces to get dimension back if they’re outside on a cloudy day, for instance. Games are almost always additive since every world starts pitch black. Because we’re free to add virtual lights anywhere without being limited by walls or ceilings, there’s a tendency to over-light things and loose contrast. That can feel very “gamey” since its apparent that you have light hitting the scene from somewhere outside of it. Personally, I like to stick to motivated lighting as much as possible, which is lighting that comes from a source that exists in the world somewhere. I’ll take advantage of window frames as light sources before I sneak some sources into the ceiling, or play up the bounce light from a pool of sunlight in the bottom of a cave.

Thinking about how light would move within a real space helps you keep a consistent approach to how you light a game environment. The big thing to keep in mind is that lighting is a universal constant. Its behavior doesn’t change regardless of the medium. It does the same thing in reality as it does in CG animated movies; bounces, diffracts, reflects, diffuses, and gets absorbed. I try to recreate those behaviors as a starting point, and then push and pull here and there for artistic license.

My overall opinion being: if I couldn’t get away with it on a sound stage, I wouldn’t do it in a game world. This mostly comes from my fascination with how movies are lit and I try to emulate some of those rules and restrictions for light placement to get a similar feeling with the visuals.