The Perspective Wall

Mackinlay, Jock D., Robertson, George G., & Card, Stuart K. (1991). The perspective wall: Detail and context smoothly. In CHI ‘91, ACM Conference on Human Factors in Computing Systems. New York: ACM, 173–179.

Mackinlay, Jock D., Robertson, George G., & Card, Stuart K

Overview: Tim Thornton

Motivation

• Information often involves "spanning" properties that give linear structure to data
• Generally two strategies for visualizing large linear data
  • Space Strategy - Pack information into one view
  • Time Strategy - Use view transitions to spread information into multiple views
• Single-view strategies: Lose focus property in order to fit all the data
• Many-view strategies: Lose context property by enlarging only part of the data at a time
• Often want both strategies: Focus + Context

The Idea

• Goal: Focus+Context view of linear data
• Idea based on Resnikoff - human eye has focused view of detail and general view of context
  • Result of information processing principles such as selective omission and aggregation
• The Perspective Wall: Folds Space-Strategy wide visual into 3D Focus+Context visual

The Visualization

• Distorts a 2D wide layout into a 3D layout by folding inward

• Combines the information presented by the single-view and many-view visuals into one
• Detail panel in center with two perspective panels on either side
• Vertical dimension can be used for representing layered data (ie. type of file)

Properties

• Detail pane can be moved throughout the visual with smooth transitions that maintain context
• Information in the perspective panes that are close to the detail pane will be larger than information farther away
• Easy to allow user to adjust ratio of detail and context (relative size of the detail pane)

Use of Space

• Compare to both detail and overview views
• Claim: 3x larger information in detail pane than in 2D overview
• Claim: 3x as much information visible than a flat wall with details of the same size

Comparing the Perspective Wall with the Detail View (front) and the Overview (back)

Applications

Inxight VizControls

http://users.dcc.uchile.cl/~rbaeza/cursos/visual/ix/

Conclusion and Discussion

• Focus+Context visualization of linearly structured data
• Combination of 3x more detail than overview, and 3x more information than detail view
• Allows smooth transitions when navigating

Discussion Points

• Any other applications other than files?
• Is the distortion a significant problem, as it could be in fisheye strategies?
• Thoughts as to why it is not commonly used today?