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Related Work

A lot of related work on the topic ``VR and data representation'' already exists. In this chapter we give a brief overview of three well known basic approaches.
In [1], a data-immersive virtual environment - called Avatar - has been developed at the University of Illinois, which explores performance data and provides real-time adaptive control application behavior. Using three-dimensional scatter-cubes, they try to give the user an overview of the performance of the parallel program. One of the advantages of three-dimensional representation is the ability of changing the viewing perspective. Through personal movements, users can explore the objects in a natural way.


  
Figure 1: Time-Tunnel display
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Figure 2: Call-graph display
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Another prototype has also been developed by the University of Illinois - called Virtue. Virtue [2] exploits human sensory capabilities to help performance analysts explore large-scale applications. One part of this project is the visualization of communication between parallel processes, displayed by a Time-tunnel (Figure 1). In other words, users are surrounded by tasks, and they can see the processor communication as well as task-computation. Therefore, analysts can see performance problems within communication, and where performance enhancements are useful.
A further part of Virtue is the Call-graph display (Figure 2). This data mapping represents procedures, vertex color and size indicate invocation count and time spend by the procedure. The labels show the names of the procedure.

The Computer Science Department at University of Wisconsin-Madison developed a tool called Devise [6], which is a generic visualization tool to allow arbitrary number of different but related data-streams to be integrated and explored visually in a flexible manner. In contrast to both other projects, they do not use Virtual Reality to display the information. Streams of data are displayed in line plots, histograms or bar charts.

Our representation is limited to three-dimensionality. We also have a Time-tunnel-like display, as well as a fractal landscape. Detailed information about our approach will be given in the next sessions.


next up previous
Next: Semantics of Byte-Streams Up: Three-Dimensional Visualization of Dynamic Previous: Analysis of large parallel
breiting at GUP
2000-04-05