Computer Graphics World

n n n n Projection using for the exhibit)," he says. "The resolu- tion for each part was 2048x1080, but the to- tal resolution was 18944x1080 due to the 11 blending areas (15 percent per screen)." The entire digital scroll was projected onto an undulating screen using 12 Christie projectors. find at least 10 or even more 'vanishing points' of perspective in it. Thus, when we produce images with 3D software, we encounter the problem that the image elements we produce do not match the original background per- spective. The contrast in those elements with less obvious perspective lines, such as human figures and animals, are not so sharp as to be noticed at the first sight, but those added ele- ments with clear perspective lines, such as ta- bles, chairs, and benches, will give us a sense of distortion. Therefore, we have to display those elements more disorderly, or make a so-called pseudo-process, so as to achieve the desired ef- fect of blurring vanishing points." Another challenge related to perspective is the animation. Yu Zheng points to the clip Rainbow Bridge as an example. "There is al- most no possibility of producing a rainbow bridge with 3D software that is exactly the same as the original painting because that violates the perspective principle of physics," he explains. "For the purpose of matching the actions of the people walking on the bridge, we may find after opening the working file that the figures are made to walk on a vertical plane without displacement in the direction of the Z axis, and the perspective of 'looking big when near and small when far' is produced by zooming. Only in this way can we combine it with the original base painting to produce a relatively reasonable motion track of cavalier perspective." The end result, though, is that the charac- ters, while created in 3D, appear to be 2D as they move perfectly about the scene in the cor- rect perspective. More than 50 computers were used in the renderfarm; the render times were as short as 15 seconds per frame (using over 150 CPUs) for the 3D animation renders, to over one and a half minutes per frame (by four CPUs) for the composite output. Overall, the project took approximately 48 October/November 2011 five months to complete the design, anima- tion, and compositing. CG Canvas Producing the animation was just one of the challenges facing the team. Because the exhibit was going to increase the size of the original artwork by 30 times, going from 5.28 meters long to 130 meters long (and 6.3 meters high), two new challenges presented themselves: the giant frame resolution and the blending and synchronization that would be needed for the multi-projector system that would be used for the final display. Twelve Christie projectors would ultimately be needed to show the scroll scene in its en- tirety on an undulating screen that runs the length of the huge pavilion. The audience walks along the length of the screen as the en- tire scene plays out from end to end. A person can view the scene many times without see- ing all the detail and action that takes place. Crystal CG holds three patents on the soft- ware used to control the projection system. By enlarging the scene so much, the team of digital artists had to inject much more detail than was originally found in the painting. Each element, from trees, to boats, to houses, was painstaking- ly textured using Photoshop, and each character needed unique clothes and facial features. During the daylight scene alone, there are 691 characters that go about their business. The increased detail the artists added allows viewers to actually watch the characters' facial expressions changing, especially as a team of camels walk slowly by, or as the characters go about the task of taking down the masts of their vessel as they sail along the river. For the issue of rendering such high-resolu- tion images, Yu Zheng says that patience, and a good renderfarm, were necessary parts of the solution. "We split the frame into 12 parts (based on the 12-projector system we were A River Runs Through It One final design element that caused some challenges was the addition of a water "moat" which was placed between the viewing audi- ence and the scroll. The so-called moat served two purposes: to keep the audience from get- ting too close to the scroll, and to serve as "a river of wisdom," says Yu Zheng. In the origi- nal design, there was to be an actual water sys- tem, but problems with the physical concept made the designers rethink the plan and turn to a digital solution instead. "The implementa- tion of real water operations and maintenance are extremely difficult. So we adjusted it into the program." This was done by projecting the screen of watermarks stitched together by 26 Christie projectors on the gauze so that some of the im- ages would show on the landscaping through the gauze under it, forming the "virtual water system" with a certain thickness, explains Yu Zheng. "The effect is real and magical where the water system contrasts finely with the Riverside Scene at the Qingming Festival on it," he adds. After two years of development and produc- tion work on the project, Yu Zheng says the most rewarding part of it all was seeing the ex- cited and surprised expressions on the faces of the audience as they viewed the exhibit. After completing such a monumental proj- ect, what do the artists at Crystal CG plan to do next? Since they have already established themselves as China's premier digital agency since their establishment in 1995, the compa- ny, with offices now in London, Tokyo, Hong Kong, and Los Angeles, will turn at least part of their company's attention to the London Games, where they will provide digital anima- tion for the opening and closing ceremonies of the Olympic and Paralympic games in 2012. With more than 2200 young artists in their employ and offices spanning the globe, Crys- tal CG is an international player in 3D digital entertainment and architectural visualization. Using technology of the future, Crystal CG was able to take a masterpiece from the past to create a beautiful exhibit in the present. And, what they have accomplished for Chinese art may one day be done for other cultural works of art. Imagine a Normal Rockwell or a da Vinci coming to CGI life. n Douglas King is a freelance writer based in Dallas. He can be reached at doug@dayiiiprod.com.

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