DETAILS


COLUMNS


CONTRIBUTIONS

a a a

SIGGRAPH 98 History Project

Vol.32 No.3 August 1998
ACM SIGGRAPH

SIGGRAPH VRML 3D Ph.D. Conetree



Dr.Norman I.Badler
University of Pennsylvania
Dr.Roger W.Webster
Millersville University

Abstract

This paper describes the work-in-progress of a VRML 3D conetree to visualize Ph.D. graduates and their Ph.D. thesis advisors in the field of computer graphics. As part of the SIGGRAPH history project chaired by Carl Machover, this VRML 3D conetree debuts publicly at the 25th conference celebration at SIGGRAPH 98, July 1998, in Orlando, FL. This conetree allows a VRML-enabled browser to visualize Ph.D. contributors to the field of computer graphics and to trace their influences and academic progeny. The database developed may seed further studies of the field’s contributors. The initial phase of this project (using Ph.D. advisors/graduates) provides a hierarchical (if arbitrary) view of part of SIGGRAPH’s academic structure.

Figure 1: Conetree with more than 700 entries.
Figure 1: Conetree with more than 700 entries.
Figure 2: View from the top of the conetree.
Figure 2: View from the top of the conetree.

Introduction

Conetrees were first developed by George Robertson, Jock Mackinlay and Stuart Card while at Xerox PARC. Their work: “Cone Trees: Animated 3D Visualizations of Hierarchical Information” was presented at SIGCHI ‘91, pgs. 189-194. A conetree is a 3D representation of a tree structure. Conetrees have been shown to be very effective information visualization tools for large data sets that are broad, shallow and hierarchical. In a conetree representation, the root of a tree (represented by a cube, a sphere or some other appropriate object) is located at the tip of a transparent cone. The children of the root node are arranged around the base of the cone. Each child can be the root node of a subtree, which is represented in a recursive fashion by a cone whose tip is located at the object representing the child.

This conetree implementation visualizes simple hierarchical relationships occurring in the data with a standard G=(V,E) graph with vertices and edges implementation. Thus, each line in a flat, ascii, datafile has a vertex and a list of its children. The output of the program is a VRML ‘cone.wrl’ file. Up to four lines of text can be associated with each node (vertex).

This database is just the beginning documentation to the human side of the meteoric rise of computer graphics. Few disciplines have the benefit of creating such biographical materials while almost all the players are still alive. We hope that the start we have made will encourage further expansion to other academic degrees or titled positions (such as graphics software engineer, degree notwithstanding!). We will be seeking avenues for such an expansion of the database so that we may more fully capture the human aspect of the computer graphics phenomenon. There are now more than 700 people in the SIGGRAPH conetree database.

The Web Site

At the Web site, you can view the entire SIGGRAPH VRML 3D Ph.D. conetree. This will load the file: cone.wrl.gz into your VRML browser The file is gzip compressed and it’s still greater than 3MB. In uncompressed form, it is over 26MB. You can also view the VRML 3D conetree data in raw html format. The VRML 3D conetree can also be viewed in 2D using a Java applet. The applet shows the 2D graph. If you are not in the SIGGRAPH conetree database you can add your data with an easy to fill out form at the Web site. If you have a long list of Ph.D. students that you have supervised, you can fax the information to +1-717-871-2320. We would rather the database be inclusive rather than exclusive, so we are happy to include any field that could be of potential interest to the SIGGRAPH community at large. Example views from the conetree are shown below.

Figure 3: Sample of SIGGRAPH conetree data in 2D with Java applet.
Figure 3: Sample of SIGGRAPH conetree data in 2D with Java applet.
Figure 4: Preliminary sketch of the display area at SIGGRAPH 98. Courtesy of Jeff Callender.
Figure 4: Preliminary sketch of the display area at SIGGRAPH 98. Courtesy of Jeff Callender.

The DataBase

The database is a flat ASCII file, and each line has the following format:

~vertex_name_text:secondlineoftext:3rdline:4thline~numberofchildren~children

Where: ‘children’ is a list of the subscripts of the vertices. Unfortunately, no spaces are allowed in the text.

Here is a simple data set (Graphics has four children: Coons, Van_Dam, Foley, Bresenham): Coons has one child: Sutherland.

~Graphics::::~4~1,2,3,4
~Coons::::~1~5
~Van_Dam::::~0~
~Foley::::~0~
~Bresenham::::~0~
~Sutherland::::~0~

Our example datafile of Ph.D. advisors and their Ph.D. graduates looks like this:

~LastName:FirstName:Date:Institution~NumberOfChildren~ChildrenList

Dr.Norman I.Badler
Center for Human Modeling and Simulation
University of Pennsylvania
Philadelphia, PA 19104-6389


Dr.Roger W.Webster
Department of Computer Science
Millersville University
Millersville, PA 17551


The copyright of articles and images printed remains with the author unless otherwise indicated.

Acknowledgments

This project was funded, in part, by the National Science Foundation under grant number DUE-9651237, and by the Faculty Grants Committee of Millersville University and by SIGGRAPH History Projects A2961-0 chaired by Carl Machover. Special thanks go to the Sense8 Corporation for technical support. The VRML conetree generator program was written in Sense8’s WorldToolKit. The Java 2D tree graph program was written in Java jdk 1.0, both by Dr. Roger Webster while on sabbatical during the Fall 1998 semester at the University of Pennsylvania’s Center for Human Modeling and Simulation.

References

  1. Ames, Andrea L., David R. Nadeau, John L Moreland. VRML 2.0 Source Book, John Wiley & Sons Publishing Company, NY, 1997. (ISBN: 0-471-16507-7).
  2. Carey, Rikk and Gavin Bell. The Annotated VRML 2.0 Reference Manual, Addison-Wesley Publishing Company, Reading, MA, 1997. (ISBN: 0-201-41974-2).
  3. Flanagan, David. Java in a Nutshell, First Edition (jdk 1.0), O’Reilly Press, Sebastopol, CA, 1996.
  4. Flanagan, David. Java in a Nutshell, Second Edition (jdk 1.1) O’Reilly Press, Sebastopol, CA, 1997.
  5. Geary, David M. Graphic Java 1.1 - Mastering the AWT, Second Edition, Sun Microsystems Press, Mountain View, CA, 1997.
  6. Hartman, Jed and Josie Wernecke. The VRML 2.0 Handbook- Building Moving Worlds on the Web, Silicon Graphics Incorporated, Addison-Wesley Publishing Company, Reading, MA, 1996. (ISBN: 0-201-47944-3).
  7. Robertson, George, Jock Mackinlay and Stuart Card. “Cone Trees: Animated 3D Visualizations of Hierarchical Information,” SIGCHI ‘91 Proceedings, pgs. 189-194.
  8. Roehl, Bernie , Justin Couch, Cindy Reed-Ballreich, Tim Rohaly, Geoff Brown. Late Night VRML 2.0 with Java, 1997. (ISBN: 1-56276-504-3).

This project was sponsored, in part, by the National Science Foundation under grant number DUE-9651237, and by the Faculty Grants Committee of Millersville University and by SIGGRAPH History Projects A2961-0.