Buxton, W. (1999).Where IT's at. CGI Magazine, December, 1999, 16-17.



 

Where IT's at


Bill Buxton
Chief Scientist
Alias|Wavefront
buxton@aw.sgi.com
www.aliaswavefront.com
September 27, 1999

Introduction:

My sense is that the computer graphics industry is at a turning point comparable to what happened in the early 1980s, when it started to emerge from the domain of flying logos, to images of nature and character animation. I see us moving into a period that will have the same excitement we experienced the first time we saw Lorne Carpenter’s film of a teapot in the fractal mountains, "Vox Libre," or Turner Whitted’s beautifully ray-traced images of crystal balls on a checkerboard table cloth, or chess pieces on a fog shrouded board.

To anticipate a turning point is one thing. To characterise it is another. Yet that is what I am going to try to do, albeit briefly.

Coming from the music technology field, I have always found that what happens in computer graphics is parallel to what happens in computer music, but delayed by a few years. This delay does not imply that computer musicians are smarter than those doing computer graphics: rather, it is a reflection that computer graphics is significantly more demanding computationally. Once recognised, this parallel can help us anticipate and understand what is to come.
 

Music Lesson # 1: Desktop Performance Animation

As computers become more powerful, so does our ability to deal with complex models interactively. For example, we can now scale, translate, rotate, mutate and animate things on desktop machines in ways we could only dream about one or two years ago. And we can do so with them fully shaded. Now, once we have reached this stage, we are confronted by the following questions:
When you manipulate a complex model in real time, what is the difference between manipulation and animation?
The answer, in my opinion, is simple:
It just depends on whether or not you have the record pedal depressed.
Like we have done with music software, we are now at a point where we can "perform" animation at the desktop, i.e., do "desktop motion caption" or "desktop performance animation." This will lead to concepts like "multi track / pass animation," where we build up and refine the animation layer by animation layer. In addition, we will refine it by something that might be called "motion mixing." In doing so, I suggest that MIDI controllers and other input devices previously seen only on musicians’ desktops, will increasingly be put to use by animators.

One result of this change will be that animation partially moves out of the back room and into the front suite. This is a result of increased interactivity, which means the 3D animator will be able to work side-by-side with the client more to refine his or her work.
 

Music Lesson #2: From Synthesis to Sampling

In music terms, the computer graphics industry is in the mid-1980s. Why? Because that is when a company called Emu brought out one of the first affordable samplers, The Emulator, and forever changed the music world. So how does that relate to those of us in computer graphics?

Think about this: until now, all of the computer graphics companies (such as Alias|Wavefront, Softimage, Kinetix, etc.), in music terms, have been synthesiser companies. That is, they created tools to synthesise images. However, one of the biggest changes over the past 12-18 months has been the introduction of a broad range of technologies that enable us to capture data from the physical world, i.e., "sample" it, and use it in our work.

Let’s look at this in more detail. Now the reason I use the term sampling rather than scanning is because (a) it helps establish the music analogy, and (b) "scanning" carries the connotation of sampling just objects, and there are many more things that can be sampled. By seeing these in the same light, under the same term, the emerging pattern becomes clearer, I hope. So, here are some examples of things that will be sampled more and more:

Going forward, digital imagery will, like today’s music, be composed of a mix of sampled and synthesised materials. Hence, to stay current, the CG packages of the future must support both types of material in a seamless and integrated manner. Recognising this and other trends early is one of the key reasons that Alias|Wavefront invests so much in research. Once recognised, this drives many new partnerships that we are developing, as well as R&D initiatives, such as applying our automotive design point-cloud processing tools to our entertainment business.
 

Music Lesson #3: Towards Physically-Based Modelling

Finally, we are starting to see signs that CG is moving into the current "hot area" of sound synthesis, physically-based modelling (PBM). PBM is the use of equations approximating the physics of an object in order to synthesise it, as opposed to creating (synthesising) or copying (sampling) its appearance. Dynamics and inverse kinematics are early uses of PBM in computer graphics. Marking a change on this front, we are now seeing a new generation of graphics engine emerge, represented by the new game engines such as the Sony Playstation 2. This will evaluate dynamics and IK in real time, rather than precompute them.

PBM will go even further than this. A good example is Jos Stam’s research (of Alias|Wavefront), which appears in the Proceedings of SIGGRAPH ‘99. This work develops a set of formulae that enable one to approximate 3D fluid dynamics (such as the behaviour of smoke, fog, or liquids) in real time on a desktop machine. The effects are dramatic, and are just a hint of what is to come, from both us and others.
 

Conclusions

We live in interesting times. For the past 5-10 years, what was a 2D and 3D graphics package was pretty well agreed upon and understood by all. Progress from year to year was mostly in the form of new features, and improved price-performance.

But I think that is over, and that the field is about to be redefined. The changes happening today, and not just those mentioned above, are going to shake up the industry. We will have to look at how we have been doing things, and at our assumptions. We will have to ask, "Have we been doing things this way because it is the right way, or because it was the only way that we knew how at the time we started doing it?"

My belief is that increasingly, we will realise that the structure of the industry is largely an artifact of the early ‘80s, when trends were set. We did things in a certain way because that was the best we could do at the time. Well, times have changed. For the first time we can begin to ask, "What is the right way to do things?" and have some hope in the ability to carry it out.

Asking such questions is easier said than done. But the future belongs to those who do. Make no mistake: we plan to be there stronger than ever.