Lighting Principles for Game Design
Before we get into lighting for games specifically, I think it's important to talk about the art of traditional lighting. It won't do us any good to know the tools and procedures if we don't have a strong artistic foundation. There have been hundreds of books written with respect to lighting theory and methodology, so I'll do my best to just touch on the most important aspects in this chapter. But I encourage you to research and learn as much about lighting as you possibly can.
Remember that everything we see around us is light. When you see an apple, you aren't seeing an apple, you are seeing the light that is reflected and bounced off the surface of that apple. Without light, the visual world as we know it does not exist. So, when you as an artist are put in the position of playing God, "Let there be light!," you'd better know what you are doing! Lighting plays a pivotal role in creating atmosphere and mood in a scene. Think about stage lighting for a play, or a dramatic film noir-style movie. Lighting alone can conjure feelings and emotions, tell a story, or even drastically change the meaning of what you are seeing.
Unless you give your characters and environments appropriate lighting, you can easily blow out and flatten the entire scene, essentially hiding all the beautiful work you have done so far. Whether you are lighting for stage, photography, film, or 3D, the primary function of lighting is to give form to the objects in the scene. The form of a three-dimensional object can be either revealed or hidden depending on how the light hits the object and at what angle with respect to the camera. Keep in mind that defining and highlighting form is the first thing you should think about when lighting. In addition to the primary purpose of defining shape, light can be a story-telling medium, affecting mood, form, color, intensity, and movement. Let's start by talking about color.
Color plays a powerful role in defining mood in a scene. We as artists all know about warm colors and cool colors, complimentary colors, and so on. But the important thing to think about is how color affects the viewer. We tend to instantly fall into the trap of cliché: Red means hot and dangerous; blue means cool and safe. There is no doubt that these colors can evoke those particular emotions and feelings if presented properly, but it is important to remember that you as an artist can evoke any emotion you want with any color. It's about defining rules within your scene and making distinct associations. Look at the movie The Matrix as an example. Using two simple hues, blue and green, we the audience were subtly taught whether a scene was taking place in the Matrix or in the real world. Adding that color information, whether you noticed it or not, really helped hold the story together and defined a rule that we were more than happy to follow.
Another aspect of color that you should think about when lighting your scene is your target audience. To most Americans, the color red typically conveys emotions of danger and immediacy. But in China, red conveys happy celebration and evokes entirely different emotions.
To us, white is associated with purity and joy, wedding dresses and baby clothes. In China, white means death. Funeral attire in China is typically white.
Knowing your audience is important to all aspects of artwork, but choosing the right colors with which to light your scene increases your chances of conveying the feeling you want. So you can see that culture and audience play a significant part in choosing color and evoking specific emotions. Figure 7.1 shows an example of the use of red that would work with an American audience.
Figure 7.1 A screenshot from RTX Red Rock using the color red to convey a sense of urgency.
Choosing the right colors in a scene has to be a balancing act. For those of you who have taken color theory and design classes, you know how dramatic an effect colors can have on one another when seen together. Too many powerful colors and the visual impact becomes chaotic and over-stimulating. Too little, and the work is drab and boring. When lighting, look at your scene as an individual piece of artwork. Be sure your colors are balanced and chosen carefully. Use colors that work well together and don't conflict (unless you want to convey a conflicting situation or emotion). Try to choose and commit to a specific set of colors (color scheme) in your scene that represents the mood you want your audience to feel. Pay close attention to the color scheme of your textures and choose light color accordingly. Figure 7.2 shows a subtle yet effective choice of colors. Notice how color is shared among objects and balanced in the room.
Figure 7.2 A subtle and pleasing balance of color in Star Wars: Knights of the Old Republic.