Designing Gestural Interfaces

A BRIEF HISTORY OF GESTURAL INTERFACES

Figure 1-4. How the computer sees us. With traditional interfaces, humans are reduced to an eye and a finger. Gestural interfaces allow for fuller use of the human body to trigger system responses. Courtesy Dan O'Sullivan and Tom Igoe.

As The Clapper illustrates, gestural interfaces are really nothing new. In one sense, everything we do with digital devices requires some sort of physical action to create a digital response. You press a key, and a letter or number appears on-screen. You move a mouse, and a pointer scurries across the screen.

What is different, though, between gestural interfaces and traditional interfaces is simply this: gestural interfaces have a much wider range of actions with which to manipulate a system. In addition to being able to type, scroll, point and click, and perform all the other standard interactions available to desktop systems,^[5] gestural interfaces can take advantage of the whole body for triggering system behaviors. The flick of a finger can start a scroll. The twist of a hand can transform an image. The sweep of an arm can clear a screen. A person entering a room can change the temperature.

Figure 1-5. If you don't need a keyboard, mouse, or screen, you don't need much of an interface either. You activate this ...