FUNDAMENTALS OF GAME DESIGN, SECOND EDITION
COLORBLIND PLAYERS
Color blindness is a sex-linked genetic disorder primarily affecting men. Total color blindness is quite rare, but one milder form (deuteranomaly) affects about 6 percent of the male population. Persons with this disorder have reduced sensitivity to different shades of green; they appear more like yellow. (So-called red-green color blindness is actually a misnomer for several related conditions.)
This issue matters most in user interface design. If you create identical objects distinguishable only by their color, and you use similar shades of yellow and green, you risk confusing the colorblind player. Vehicles or characters in a strategy game whose appearance is identical except for their color would be an example. Also be careful with indicators, such as colored lights, that turn yellow or green. Colorblind drivers can tell the difference between yellow and green traffic lights because the yellow and green lights are separate lights, so even if the driver can't see a difference, he can tell whether the signal is yellow or green by its position (the middle light is always the yellow light). You can adopt this convention too: make more than one light, with the yellow light in a predictable location. If you don't have room and have to make do with a single light, use colors other than yellow and green, such as black and white or black and green.
You can test the appearance of your artwork to players with different forms of color blindness at the Vischeck web site, www. vischeck. com.
