FUNDAMENTALS OF GAME DESIGN, SECOND EDITION
Mobility Impairments
The best thing you can do for mobility-impaired players is to reduce the time pressure required to accomplish tasks. Many people with physical impairments can manage well enough given time, but they don't always get the time. If it's feasible, include a switch that lets the player adjust the speed of the game. There's no such thing as too slow.
Keep your control set simple. Strange Attractors, one of the finalists at the Independent Game Festival in 2006, uses a single button for player control. Weird Worlds: Return to Infinite Space uses a purely mouse-based interface. Researchers are also working on ways to adapt games and game controllers to what is called singleswitch operation; see "Accessibility Resources" later in this section for more details. Obviously not all games can make do with so few controls, but even if you're not
specifically designing for the mobility-impaired, you will find it a useful exercise to ask yourself how well a mobility-impaired person would do trying to use your interface. If your answer is "not that well," perhaps you should revisit the design of your interface.
If you implement fidgets for characters while they're not doing anything, don't include any that make fun of the player for being slow. (Sonic, in Sonic the Hedgehog, used to fold his arms, tap his foot, and look irritated if the player didn't do anything for a certain length of time.) Use animations that don't appear to pass judgment.
