pointing

Computing devices within current work and play environments are relatively static. As the number of 'networked' devices grows, and as people and their devices become more dynamic, situations will commonly arise where users will wish to use 'that device there' instead of navigating through traditional user interface widgets such as lists. This paper describes a process for identifying devices through a pointing gesture using custom tags and a custom stylus called the gesturePen. Implementation details for this system are provided along with qualitative and quantitative results from a formal user study. As ubiquitous computing environments become more pervasive, people will rapidly switch their focus between many computing devices. The results of our work demonstrate that our gesturePen method can improve the user experience in ubiquitous environments by facilitating significantly faster interactions between computing devices.

We explore the design space of freehand pointing and clicking interaction with very large high resolution displays from a distance. Three techniques for gestural pointing and two for clicking are developed and evaluated. In addition, we present subtle auditory and visual feedback techniques to compensate for the lack of kinesthetic feedback in freehand interaction, and to promote learning and use of appropriate postures.

We present HybridPointing, a technique that lets users easily switch between absolute and relative pointing with a direct input device such as a pen. Our design includes a new graphical element, the Trailing Widget, which remains "close at hand" but does not interfere with normal cursor operation. The use of visual feedback to aid the user's understanding of input state is discussed, and several novel visual aids are presented. An experiment conducted on a large, wall-sized display validates the benefits of HybridPointing under certain conditions. We also discuss other situations in which HybridPointing may be useful. Finally, we present an extension to our technique that allows for switching between absolute and relative input in the middle of a single drag-operation.

Position control devices enable precise selection, but significant clutching degrades performance. Clutching can be reduced with high control-display gain or pointer acceleration, but there are human and device limits. Elastic rate control eliminates clutching completely, but can make precise selection difficult. We show that hybrid position-rate control can outperform position control by 20% when there is significant clutching, even when using pointer acceleration. Unlike previous work, our RubberEdge technique eliminates trajectory and velocity discontinuities. We derive predictive models for position control with clutching and hybrid control, and present a prototype RubberEdge position-rate control device including initial user feedback.

Cascading menus are commonly seen in most GUI systems. However, people sometimes choose the wrong items by mistake, or become frustrated when submenus pop up unnecessarily. This paper proposes two methods for improving the usability of cascading menus. The first uses the direction of cursor movement to change the menu behavior: horizontal motion opens/closes submenus, while vertical motion changes the highlight within the current menu. This feature can reduce cursor movement errors. The second causes a submenu to pop up at the position where horizontal motion occurs. This is expected to reduce the length of the movement path for menu traversal. A user study showed that our methods reduce menu selection times, shorten search path lengths, and prevent unexpected submenu appearance and disappearance.

Soap is a pointing device based on hardware found in a mouse, yet works in mid-air. Soap consists of an optical sensor device moving freely inside a hull made of fabric. As the user applies pressure from the outside, the optical sensor moves independent from the hull. The optical sensor perceives this relative motion and reports it as position input. Soap offers many of the benefits of optical mice, such as high-accuracy sensing. We describe the design of a soap prototype and report our experiences with four application scenarios, including a wall display, Windows Media Center, slide presentation, and interactive video games.

Interaction on digital tables has been restricted to a single layer on the table's active work-surface. We extend the design space of digital tables to include multiple layers of interaction. We leverage 3D position information of a pointing device to support interaction in the space above the active work-surface by creating multiple layers with drift-correction in which the user can interact with an application. We also illustrate through a point-design that designers can use multiple-layers to create a rich and clutter free application. A subjective evaluation showed that users liked the interaction techniques and found that, because of the drift correction we use, they could control the pointer when working in any layer.