Toolglass ™ widgets are new user interface tools that can appear, as though on a transparent sheet of glass, between an application and a traditional cursor. They can be positioned with one hand while the other positions the cursor. The widgets provide a rich and concise vocabulary for operating on application objects. These widgets may incorporate visual filters, called Magic Lens™ filters, that modify the presentation of application objects to reveal hidden information, to enhance data of interest, or to suppress distracting information. Together, these tools form a see-through interface that offers many advantages over traditional controls. They provide a new style of interaction that better exploits the user’s everyday skills. They can reduce steps, cursor motion, and errors. Many widgets can be provided in a user interface, by designers and by users, without requiring dedicated screen space. In addition, lenses provide rich context-dependent feedback and the ability to view details and context simultaneously. Our widgets and lenses can be combined to form operation and viewing macros, and can be used over multiple applications.

information visualization, information physics. We describe the current status of Pad++, a zooming graphical interface that we are exploring as an alternative to tradhional window and icon-based approaches to interface design. We discuss the motivation for Pad++, describe the implementation, and present prototype applications. In addition, we introduce an informational physics strategy for interface design and briefly compare it with metaphor-based design strategies.

Although information visualization (infovis) technologies have proven indispensable tools for making sense of complex data, wide-spread deployment has yet to take hold, as successful infovis applications are often difficult to author and require domain-specific customization. To address these issues, we have created prefuse, a software framework for creating dynamic visualizations of both structured and unstructured data. prefuse provides theoretically-motivated abstractions for the design of a wide range of visualization applications, enabling programmers to string together desired components quickly to create and customize working visualizations. To evaluate prefuse we have built both existing and novel visualizations testing the toolkit's flexibility and performance, and have run usability studies and usage surveys finding that programmers find the toolkit usable and effective.

In this paper we investigate the use of scene graphs as a general approach for implementing two-dimensional (2D) graphical applications, and in particular Zoomable User Interfaces (ZUIs). Scene graphs are typically found in three-dimensional (3D) graphics packages such as Sun's Java3D and SGI's OpenInventor. They have not been widely adopted by 2D graphical user interface toolkits. To explore the effectiveness of scene graph techniques, we have developed Jazz, a general-purpose 2D scene graph toolkit. Jazz is implemented in Java using Java2D, and runs on all platforms that support Java 2. This paper describes Jazz and the lessons we learned using Jazz for ZUIs. It also discusses how 2D scene graphs can be applied to other application areas. Keywords Zoomable User Interfaces (ZUIs), Animation, Graphics, User Interface Management Systems (UIMS), Pad++, Jazz. INTRODUCTION Today's Graphical User Interface (GUI) toolkits contain a wide range of built-in user interface objects (also kno...

In this paper, we analyze toolkit designs for building graphical applications with rich user interfaces, comparing polylithic and monolithic toolkit-based solutions. Polylithic toolkits encourage extension by composition and follow a design philosophy similar to 3D scene graphs supported by toolkits including Java3D and OpenInventor. Monolithic toolkits, on the other hand, encourage extension by inheritance, and are more akin to 2D Graphical User Interface toolkits such as Swing or MFC. We describe Jazz (a polylithic toolkit) and Piccolo (a monolithic toolkit), each of which we built to support interactive 2D structured graphics applications in general, and Zoomable User Interface applications in particular. We examine the trade offs of each approach in terms of performance, memory requirements, and programmability. We conclude that a polylithic approach is most suitable for toolkit builders, visual design software where code is automatically generated, and application builders where there is much customization of the toolkit.

user interface management system (UIMS). We describe Pad++, a zoomable graphical sketchpad that we are exploring as an alternative to traditional window and icon-based interfaces. We discuss the motivation for Pad++, describe the implementation, and present prototype applications. In addition, we introduce an informational physics strategy for interface design and briefly contrast it with current design strategies. We envision a rich world of dynamic persistent informational entities that operate according to multiple physics specifically designed to provide cognitively facile access and serve as the basis for design of new computationally-based work materials. 1 To appear in the Journal of Visual Languages and Computing.

Magic Lens filters are a new user interface tool that combine an arbitrarily-shaped region with an operator that changes the view of objects viewed through that region. These tools can be interactively positioned over on-screen applications much as a magnifying glass is moved over a newspaper. They can be used to help the user understand various types of information, from text documents to scientific visualizations. Because these filters are movable and apply to only part of the screen, they have a number of advantages over traditional windowwide viewing modes: they employ an attractive metaphor based on physical lenses, show a modified view in the context of the original view, limit clutter to a small region, allow easy construction of visual macros and provide a uniform paradigm that can be extended across different types of information and applications. This paper describes these advantages in more detail and illustrates them with examples of magic lens filters in use over a variety...

In this paper we present a system that electromagnetically tracks the positions and orientations of multiple wireless objects on a tabletop display surface. The system offers two types of improvements over existing tracking approaches such as computer vision. First, the system tracks objects quickly and accurately without susceptibility to occlusion or changes in lighting conditions. Second, the tracked objects have state that can be modified by attaching physical dials and modifiers. The system can detect these changes in realtime. We present several new interaction techniques developed in the context of this system. Finally, we present two applications of the system: chemistry and system dynamics simulation. Keywords Tangible user interface, interactive surface, object tracking, two-handed manipulation, system dynamics, augmented reality

In current interfaces, users select objects, apply operations, and change viewing parameters in distinct steps that require switching attention among several screen areas. Our See-Through Interface ™ software reduces steps by locating tools on a transparent sheet that can be moved over applications with one hand using a trackball, while the other hand controls a mouse cursor. The user clicks through a tool onto application objects, simultaneously selecting an operation and an operand. Tools may include graphical filters that display a customized view of application objects. Compared to traditional interactors, these tools save steps, require no permanent screen space, reduce temporal modes, apply to multiple applications, and facilitate customization. This paper presents a taxonomy of see-through tools that considers variations in each of the steps they perform. As examples, we describe particular see-through tools that perform graphical editing and text editing operations.

Navigating and viewing large information spaces, such as hierarchically-organized networks from complex realtime systems, suffer the problems of viewing a large space on a small screen. Distorted-view approaches, such as fisheye techniques, have great potential to reduce these problems by representing detail within its larger context but introduce new issues of focus, transition between views and user disorientation from excessive distortion. We present a fisheyebased method which supports multiple focus points, enhances continuity through smooth transitions between views, and maintains location constraints to reduce the user’s sense of spatial disorientation. These are important requirements for the representation and navigation of networked systems in supervisory control applications. The method consists of two steps: a global allocation of space to rectangular sections of the display, based on scale factors, followed by degree-of-interest adjustments. Previous versions of the algorithm relied solely on relative scale factors to assign size; we present a new version which allocates space more efficiently using a dynamically calculated degree of interest. In addition to the automatic system sizing, manual user control over the amount of space assigned each area is supported. The amount of detail shown in various parts of the network is controlled by pruning the hierarchy and presenting those sections in summary form. KEYWORDS: graphical user interface, supervisory control systems, information space, hierarchical network, information visualization, fisheye view, navigation.