3D Animation Workshop: Lesson 29: VRML 97--On the Move
Lesson 29 - VRML 97--On the Move - Part 1
I had the honor of hearing Carl Rosendahl speak the other night to students and faculty at Cogswell College in Silicon Valley (where I teach 3D modeling and animation). Mr. Rosendahl is the founder and president of Pacific Data Images, one of the most important players in the 3D graphics world. Rosendahl founded PDI shortly after graduating from Stanford in 1979 on the assumption that computers could be put to work producing graphics. He was, of course, very far-sighted, and has earned the rewards of his vision. Today, PDI is 40 percent owned by Dreamworks (the Speilberg, Katzenberg, Geffen group), and is engaged primarily in the production of major animated motion pictures in competition with Pixar-Disney.
Mr. Rosendahl's observations on the big picture for 3D graphics were surprisingly appropriate to our current topic. He noted that 3D technology first earned its place in entertainment as an alternative to traditional film effects. Visual effects could be accomplished more easily and economically than ever before. The key was realism. Much effort was expended over the years to produce increasingly convincing objects and actions. This technology is now so well established that it is often hard for even a practiced eye to tell whether film or video imagery is live or computer-generated.
Rosendahl stressed, however, that the new direction and driving force in 3D technology is interactivity. The computer games industry, which has emerged as an entertainment force rivaling motion pictures and broadcast programming, has led the charge into interactive 3D. But the wider ramifications are much greater. Interactivity is the inherent end of 3D graphics, its obvious goal and terminus. Rosendahl was alerting his audience to a major trend in the field, and the observations of such an individual must carry considerable weight.
It is, of course, natural to think of VRML's use on the Internet, and a great deal of the VRML specification is directed toward exploiting cyberspace. But VRML technology is of much greater general significance in establishing standards for interactive 3D graphics (and sound), whether on the Web or off it. I believe that it is crucial to learn these evolving standards right now so that a fertile ground can be laid for viable commercial and artistic developments in interactive 3D. It is easy enough to feel disappointed in the first fruits of this technology, but perceptive people must realize that critical improvements will gather swiftly-- in little enough time to learn the skills and jump on board. In short, I believe that VRML is the best approach for catching the rising tide of interactive 3D that will be employing so many of our new and future 3D artists.
Enough evangelism. Let's get back to work.
The VRML 2 specification (now finalized as VRML 97) was promoted under the title "Moving Worlds." The VRML 1 specification was essentially static (although the camera could be animated). The Moving Worlds specification has merged two ideas--animation and interactivity--in the most general and remarkable way. This lesson will get us started with the animation side of the picture, and we'll jump to interactivity next time.
Traditional 3D computer animation as we know it is essentially the method of film. A sequence of images is run before the viewer at a speed (frame rate) fast enough to generate an illusion of continuous motion. The output of a 3D animation package is a sequence of pre-rendered still images, exactly like the sequence of frames on a reel of motion picture film. The image sequence is then formatted for computer video (e.g., .avi format), put to videotape in a videotape format, or even printed frame-by-frame to film for motion picture use. In any case, the animation is a sequence of pre-rendered frames.
The approach in VRML is radically different, as we shall see.
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Created: Dec. 8, 1997
Revised: Dec. 8, 1997