Designing Gestural Interfaces

POINT TO SELECT/ACTIVATE

WHAT

Pointing with a finger or an object either turns on (activates) an object or selects it for further manipulation.

USE WHEN

Use Point to Select/Activate to select objects on-screen or in the environment so that you can interact with them by sending commands to them.

WHY

Pointing is the most natural gesture for selection.

HOW

Point to Select/Activate requires the ability to detect the orientation of the user's hand. This can be accomplished via cameras or other means involving objects held in the hand (e.g., a remote control) or worn on the hand (e.g., a glove) that can indicate the position of the hand in relation to other objects (either in the environment or on-screen). In an environment, each object could have an individual sensor attached to it that detects when a hand is pointing at it (e.g., via a beam of infrared light).

EXAMPLES

Figure 4-7. The Wiimote works with a stationary sensor bar on top of the TV screen, allowing users to use the device to Point to Select items on-screen. Courtesy Herman Yung.

Figure 4-8. Users can Point to Select items in retail store windows using the GestPoint system. Courtesy GestureTek.

Figure 4-9. Johnny Chung Lee demonstrating one ...