Published by OneSwitch.org.uk Wednesday, 2 December 2009 9:09 pm.
The "Gamma 4" competition seeks to encourage unique one-button game experiences. The submission deadline is the 31st of January 2010. This has the potential to be a fantastic thing for those who normally use a single button, or accessibility switch, to play games. For curious coders and game designers interested this far...
CONTROLS: The Gamma 4 rules state that the single game control must be accessible via the "A" button of an Xbox 360 controller (recognised by a PC as generic joystick button "1"). If games stick to this alone then the game will not be compatible with many PC/Mac accessibility switch interfaces. Bad news for many disabled gamers. The good news is that there is nothing in the rules preventing controls also being mapped to the SPACE BAR and the LEFT MOUSE BUTTON. That will offer a way to play to the vast majority of players using alternative input devices such as switch adapted mice. If using a game development tool that does not support joystick input, you can use JoyToKey to get around this issue as I understand. Don't forget to give people a way to quit your game too.
THE WONDERFUL WORLD OF ONE-SWITCH GAMES: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 examples.
TOO BLOOMIN' HARD!: Many one-button games are ruined by a difficulty level set sky-high beyond an individual's ability and patience. Difficulty level adjustment options can make all the difference. And for some, there is no such thing as too easy. Just make it optional. Tinker with and play Aurikon to see a shining example.
ONE-BUTTON MENU: There are quite a few ways to make a one-button accessible menu system. Alice Amazed has a nice scanning system with speed control, as well as a really nice high-score entry system. The Pyramid has a tap and hold system that works well too. Don't forget that there are millions in the world who can't read English. Icons can be a big help. Quick and easy starting is a must for "Pick up and Play" too, so avoid cluttering up your front screen with too many options all in one go.
MULTIPLAYER alternating: The simplest accessible implementation, within the rules, would be for players to take turns with a single shared controller with the function of button 'A' duplicated to the SPACE BAR and LEFT MOUSE CLICK. Think multi-player pinball playable with a single button and you're there.
MULTIPLAYER simultaneously: The Gamma 4 rules allow the use of multiple Xbox 360 controllers, providing that button "A" will act as the game control. To improve accessibility and affordability further, I recommend allowing players to choose their own control in the style of Scorch Went Bonkers and Mystic Mine. Alternatively, duplicate the function of button 'A' for Player 1 to the SPACE BAR and LEFT MOUSE CLICK; and for Player 2 to the ENTER/RETURN key and RIGHT MOUSE CLICK. Beyond that define your own controls as there is no present standard beyond two-players. See the top 5 one-switch multiplayer games list for more inspiration.
MORE HELP?: One Switch, Special Effect and the IGDA GASIG are all very happy to take a look at any works in progress, to give support and ideas for tweaking and improving accessibility. Often times there might be just one or two things stopping an average game from being a really great game for disabled players. We'd all be very happy to support people in making their game more accessible for more players.