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Motor Skill Learning in User Interfaces via Discretized Pie Menus

Caveats of Discretized Pie Menus

In practice, there are various caveats to the proposed interface system. Depending on the game, the number of key presses required to navigate a multilevel menu may increase MT to an unacceptable amount. This problem can be circumvented by providing shortcut keys to sublevels within the menu. Assigning the shortcut keys such that it suggests an obvious "home" position on the keyboard/gamepad enable the user to continue motor skill learning. Obviously, forcing the user to learn too many shortcut keys will attenuate the effectiveness of the interface.

Anecdotal evidence also suggest discretized pie menus have a short but very steep learning curve. This is possibly because the interface requires an input protocol that vastly differs from other traditional input protocols. Therefore the difficulty may drop as more developers adopt this scheme. Ultimately however, the difficulty depends on the difficulty of the game. Since all actions required in a game can be placed in one hierarchical pie menu, it easy to overwhelm the novice player with too many options.

Despite these caveats, discretized pie menus keep the game interface clean while allowing players to learn using robust motor skill memory. Once players overcome a short learning curve, they can perform actions quickly and efficiently. Finally, discretized pie menus are scalable to different input devices including mouse, keyboard, and gamepad.

About the Author

Jonathan Mak is an independent developer exploring phenomena in player-game interactions. He is currently developing the abstract, action-strategy game, Gate 88.

WWW: http://www.queasygames.com/
EMAIL: jon.mak@utoronto.ca.


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