Issue: Volume: 24 Issue: 3 (March 2001)


SnowWorld was not only created and powered by MultiGen-Paradigm's Vega and Creator products, but was conceived and created by a team of engineers and artists at MultiGen-Paradigm (a division of Computer Associates). SnowWorld is currently maintained by a team of engineers at SimWright, and can be seen at

It's great to see that the program continues and that people are reaping the benefits of HIT project leader Hunter Hoffman's vision and tireless efforts.
Charles Walters
Visual Simulation
Content Manager
A Computer Associates Company

I was attracted by the image of a nicotine molecule in the Techwatch article "A Closer Look at Distance Fields" on pg. 13 of the December 2000 issue. Your description of the graphical advantages associated with the use of distance fields by the Mitsubishi Electric Research Laboratory (MERL) was equally stimulating. This presents a novel approach, and I am very glad to have discovered it by reading your article. Such out-of-the-blue stimulation is an essential nutrient to the mind of a scientist.

NASA Ames researcher Dr. Chris Henze and I have collaborated on another visualization project that has some interesting parallels to the distance-field sampling technique described in your article. Your piece made me realize that the molecular function we are focusing on, the Laplacian of the electronic charge distribution, is itself a kind of distance field. I look forward to additional instances of intellectual cross-fertilization from future issues of Computer Graphics World.

Preston J. MacDougall
Associate Professor of Chemistry
Middle Tennessee
State University
Murfreesboro, TN

Expert Q&A

Q. I do residential design in AutoCAD, and I am looking for a program that will let me switch to 3D with ease. I've looked at several packages, but I don't like what I see with regard to sections: I can't see clear details of the connections. Are there any programs that will let me view floor, elevation, and cross-section plans?

A. All 3D architectural CAD programs-ArchiCAD, DataCAD Plus, Arris, Autodesk ArchitecturalDesktop, VectorWorks-essentially do "schematic" 3D design. None will show you real section details automatically. The concept in all these programs is that you zoom into the sections and, using your construction knowledge and the 2D drafting abilities of that CAD software, do those details yourself.

Q. Do you think AutoCAD will be coming to OS X on the Mac?

A. The short answer is no. It is, however, a loaded question. AutoCAD is the standard for several areas of engineering drafting, and OS X is rumored to be the most powerful and easy to use operating system ever. Most importantly, OS X has true and automatic "symmetric multiprocessing," which means that a Mac G4 with several CPUs really will run twice as fast or faster without having special software, which is a huge leap over the Windows/Pentium world. Any CAD software on such a system would run circles around anything else.

To read the complete answers to these questions and others, visit the Expert Q&A section of Computer Graphics World online at, where Geoffrey Moore Langdon, AIA, author of Architectural CADD: A Resource Guide to Design and Production Software Appropriate for Architects, has posted answers to questions regarding architectural CADD.

We welcome any insights you have to offer that would further our readers' understanding of topics discussed in this issue, or that concern the computer graphics industry in general. We may edit your comments to conform to our style and space requirements.

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