Information Visualization Using 3D Interactive Animation

1. Information Visualization Using 3D Interactive Animation George G. Robertson, Stuart K. Card, and Jock D. Mackinlay Meng Tang 05/17/2001

2. Motivations • Goal • Lower the cost of finding information and accessing it • Strategies • Making the user’s immediate workspace larger • Enabling user interaction with multiple agents • Increasing the real-time interaction • Using visual abstraction to speed information assimilation and retrieval.

3. Technology Advances • 3D graphics hardware • 3D transformations, hidden-surface removal, double-buffered animation, antialiasing, lighting and surface models. • 3D graphics libraries • OpenGL, PEX

4. Information Visualizer

5. Information Access vs. Document Retrieval • Document retrieval • Interest --> documents • Recall & Precision • Document retrieval is part of information use • Information is used to produce more information • New information is usually at a higher level of organization relative to some purpose

6. Information Workspaces • A virtual environment for finding information and accessing it. • Not just with the retrieval of information from a distant source, but also with the accessing of that information once it is retrieved and in use • Rooms System • Extend the desktop to multiple workspaces. • User can switch among multiple workspaces.

7. Information Workspaces

8. Information Workspaces • Improving rooms system • Objective: • Decrease the costs for performing information-intensive tasks, or, alternatively, to increase the scope of information that can be utilized for the same cost. • Method: • Large Workspaces -- Make the immediate workspace virtually larger • Agents – Delegate part of the workload to semiautonomous agents • Real-Time Interaction – Maximize the interaction rates • Visual abstractions – Speed assimilation and pattern detection

9. Information Workspaces

10. UI Architecture • Several Problems • Multiple Agent Problem: How can system manage the interaction of multiple asynchronous agents. • Animation Problem: How can system provide smooth interactive animation • Interaction Problem: How can 3D widgets be designed and coupled to appropriate application behavior. • Viewpoint Movement Problem: How can the user changed the point of view rapidly and simply • Object Movement Problem: How can objects be easily moved about in a 3D space • Small Screen Space Problem: How can the dynamic properties of the system be utilized to provide the user with an adequately large work space.

11. UI Architecture

12. Cognitive Coprocessor • What is Cognitive Coprocessor • An animation loop and a scheduler for agents • An impedance matcher between the cognitive and perceptual information processing requirements of the user and the properties of these agents • 3 sorts of time constants • Perceptual processing time constant (0.1sec) • Immediate response time constant (1sec) • Unit task time constant (5~30sec)

13. Cognitive Coprocessor • Perceptual processing time constant • Governor: reduce the quality to keep the frame rate. • Immediate response time constant • Agents provide status feedback at intervals no longer than this time constant • Immediate response animation • Unit task time constant • Time to complete a task • User can start the next request as soon as sufficient information has developed from the last request or even in parallel with it

14. Cognitive Coprocessor

15. Interactive Objects • Interactive objects • Basic building block in the Information Visualizer • Generalization of Rooms Buttons • 2D/3D appearance • Allow mouse-based input (press, rubout, check, flick)

16. 3D Navigation and Manipulation • Overview • Doors • Walking metaphor • Point of interest logarithmic flight • Object of interest logarithmic manipulation

17. Information Visualization • Goal: • Attempts to display structural relationships and context that would be more difficult to detect by individual retrieval requests. • 5 sorts of data organizations • Hierarchical: Cone Tree • Linear: Perspective Wall • Spatial: Structural browser • Continuous Data: Data sculpture • Unstructured: Information grid

22. Cone Tree

23. Cone Tree • Properties of Cone Tree • Each layer has cones of the same height • Cone base diameters for each level are reduced in a progression so that the bottom layer fits in the width of the room. • Body of each cone is shaded transparently • Text is shown only for the selected path • Manipulation of Cone Tree • Select nodes

24. Cone Tree • Advantages • the use of interactive animation to move some of the cognitive load to the human perceptual system • Using the depth to fill the screen with more information • Aspect ratio of cone tree is fixed • Fisheye view (brighter, closer, larger) • Disadvantages • Complex user interactions to access some of the information • fixing the aspect ratio limits the number of levels of the cone tree

26. Cone Tree

27. Perspective Wall • Obstacles to a visualization of linear information structures • The large amount of information that must be displayed • The difficulty of accommodating the extreme aspect ratio of the linear structure on the screen. • Disadvantages of Overview-Working View structure • Important contextual information, such as the neighborhood of the viewing region is just as small as unimportant details • Increase the space of overview leads to reduce the space of working view

29. Perspective Wall • Advantages • Integrate detailed and contextual views • Smooth transitions of views • Retain any 2D task-specific features • No special large- and small-scale versions of items must be designed • Ratio of detail an context is adjustable

31. Tracing Data Paths in 3D Graphics

32. Tracing Data Paths in 3D Graphics • Number of errors in detecting paths in tree structures is substantially reduced if a 3D display method is used. • A tree structure is not necessarily a good candidate for 3D visualization