Issue: Volume: 24 Issue: 11 (November 2001)

lasting impressions



By Barbara Robertson

All images © Umesh Shukla.

For years, animator Umesh Shukla's dream has been to see a feature animation created with 3D graphics and rendered entirely in an impressionist style. Indeed, in the opinion piece, "Beyond Realism" (see Viewpoint, December 1999, pg. 22), he wrote, "I believe that in order to gain status as fine artists, CG animators need to follow the example of the impressionists and begin presenting alternative in terpretations of reality."

So this year, when he found time between a job he was leaving at Disney Feature Animation and one he was about to start at DreamWorks, he took mouse in hand, put his money where his mouth was, and decided to produce a short animation in an impressionistic style. "I wanted to do some thing quickly that would show people it can be done," he says. In the process of creating that film, "Still I Rise," his preconceived notions of how to create a painterly look changed as he discovered inexpensive tools that allowed him to achieve masterful results.

For a story, he turned to a subject he had long found fascinating: Joseph (aka John) Merrick, the elephant man. "I was watching a documentary on the Discovery Channel a few years back and caught the last four lines of Merrick's autobiography, 'Was I so tall, could reach the pole, or grasp the ocean with a span; I would be measured by the soul, the mind's the standard of the man.' They hit me straight on. I bought every book I could get, and the more I read, the more I admired him for not jumping off a cliff. Living with that kind of deformity was very difficult."
Shukla's "alternative interpretation of reality" suggests what Joseph Merrick, the elephant man, might have envisioned in his last dream.




It was so difficult that one afternoon in 1890, rather than sleeping with his head on his knees as usual, Merrick lay down on his bed and suffocated. Shukla says, "He knew he wasn't supposed to lie flat on his back; he knew it could be fatal. But he did anyway." Shukla began wondering what Merrick's dreams might have been as he fell asleep for the last time, and those thoughts coalesced into a story for the film. When Shukla realized that the impressionist painter Vincent Van Gogh committed suicide a few months after Merrick died, he decided to create the film in Van Gogh's impressionist style.

Once he had a storyboard sketched out, he assembled a team of people interested in working on the independent project. The team chose to use a technique described in a paper written by Barbara J. Meier that was published in the 1996 Siggraph Proceedings for creating and placing brush strokes on each point of a 3D model. They began running tests using Van Gogh's paintings as reference images for the brush strokes. "The tests were successful," Shukla says, "but it was taking a long time to do, and people began losing interest in the project. They had their own lives." He began working on his own.
Shukla used Poser for animation, Video Gogh to turn rendered images into impressionistic oil paintings, and Houdini to composite images and to create a staggered dissolve.




"Fortunately, my animation needs were fairly simple," he says. "I didn't need fancy IK or muscle deformation systems. There were no characters emoting." In fact, he discovered that Creative Labs' Poser was sufficient for the animation. He imported models already created by the team into Poser, and also bought additional rigged models created for Poser users.

It became clear, though, that he wouldn't have time to use the lengthy brush-stroke rendering technique. After experimenting unsuccessfully with generating point data from within Side Effects Soft ware's Houdini, Shukla decided to try optical flow; that is, to try manipulating rendered images with post processing techniques. For this, he discovered a software program from RE:Vision Effects, coincidentally titled Video Gogh. To give each element of the film a unique look, he first painted texture maps that had the color and light information he wanted. Next, he animated the 3D models and rendered them with the painted textures. Then, he sent the resulting images through Video Gogh, which gave them an abstract look by, in effect, stamping the images with an "oil paint" brush using colors from the underlying image.
Running Video Gogh's image processing techniques on renderings of 3D models produced the final look. To control how abstract the final images would be, Shukla altered the models' painted texture maps.




To give the "oil paint" a thicker look, Shukla created mattes of the images in Houdini and then layered them one on top of another so that they were slightly overlapping. Finally, again within Houdini, he composited all the elements together and used a technique called "staggered dissolve" to blend the animating elements in a painterly manner. "Usually when you are doing a dissolve, one image dissolves into another image. Instead, I wanted four or five images dissolving into each other continuously." He was able to do that by writing expressions in Houdini to manage the staggered dissolves.

Happily, the techniques he chose not only saved time, they provided a second advantage-he didn't have the jittery line problem that often plagues animations rendered with non-photorealistic techniques. Video Gogh tracks pixels to generate brush strokes, which helped solve the problem, as did the dissolve technique he used.
By using a technique called "staggered dissolve," which he implemented in Houdini, Shukla gave the animation an impressionist feel as well as an abstract look.




Would Shukla return to 3D rendering techniques now that he's learned how to make images he likes with optical flow image processing? "I debated a long time and compared and compared and compared," he says. "What guided me was that I needed to produce a painterly product in a given time frame." Ultimately, his only complaint was that the 2D tools weren't as flexible as the 3D techniques.

In "Still I Rise," the elephant man is able, during this last dream, to do the things he wasn't able to do in his life-simple things like swimming and enjoying nature. "At the end, he's just sitting there enjoying the rain," says Shukla.

Although "Still I Rise" isn't a feature animation, by making it, Shukla has realized at least part of his own dream. "I have learned so many things," he says. "I now consider impressionist techniques to be the easiest to produce in CG. I hope that by putting this film out in front of everybody, someone will get drawn to it and start thinking about using a painterly look for a feature."

The film "Still I Rise" can be seen at www. umeshshukla.com.




Barbara Robertson is Senior Editor, West Coast, for Computer Graphics World.