Computer Graphics World

May 2009 43 Modeling n n n n It's a Jungle e highlight of the sequence, with- out question, is when the plane careens through the jungle after running out of space on the dirt runway. Some shots in the crash sequence were filmed with a practi- cal cockpit set surrounded by greenscreen. Outside the cockpit windows, the Entity FX team composited CG scenes of the is- land and jungle. "One of the biggest challenges was how to build the island to the level of detail needed in such a short time frame," notes Suskin. "is really was a scene with feature-film aspirations that had to fit within the budget and tight schedule of a TV show." To accomplish this, the group used a combination of commercial and in-house software. e terrain modeling was done in Autodesk's Mudbox, while the vegeta- tion—comprising approximately one mil- lion high-resolution trees, palm trees, and plants—was crafted mainly in LightWave and textured in Photoshop. Several layers of vegetation, added in compositing using Eyeon's Digital Fusion, established the ac- tual look and photorealism. While the island is only about eight miles long, in CG terms it is much larger. "We estimated the polygon count of the CG island environment at over 62 billion," Bredereck points out. To render such an enormous environ- ment required the creation of proprietary software. Adapting a volumetric and in- stancing system the artists had previously used for bees, flies, and character work, the group was able to adapt the tool to make multiple copies of objects (in this case, the vegetation) without eating up a lot of memory. Each plant is computed once, though there may be 100,000 copies of it in the scene. "Without the code, it would have been impossible to render that many plants," adds Bredereck. e group also used the instancing plug-in to populate the digital landing strip with grass clumps, dirt particles, and sand. Additionally, Eden used its proprietary rendering-control software, Red Five, and proprietary layer management software, R2D2, to organize the multiple render lay- ers, such as specular, ambient occlusion, and diffuse buffers. "ese trees don't really have polygons when they are instanced and rendered, so they don't have real motion vectors. We had to come up with a script to get the post-process motion-blur going," notes Bredereck. Furthermore, the island comprises very high resolution displacement maps and normal maps, and to create the UV cod- ing for those maps, the Entity team used Luxology's Modo. Planning was another key to accom- plishing this task. "We knew at some point we would have to pull the trigger on ren- ders that reached from 100 to 500 minutes per frame, so we had to carefully manage our time to avoid having to re-render dur- ing the last few days before the show aired," says Hance. One way the group stayed ahead of the curve was by rendering the in- formation with the highest dynamic range possible the first go-around. "at was challenging in the beginning but saved us in the end," Hance adds. "We could change just about any tree in com- positing and all the shadows; the different aspects of the scene could be changed in comp without re-rendering. at really helped us do the entire production in the short time frame we had." On the backside, Eden had 130 nodes processing the information. e machines were dual quad-core systems running Win- dows. Prior to this job, the group had a base network of machines with 4 gigs of RAM but had to increase that to 8 gigs. So, what exactly sold the scene? Accord- ing to Gross, the CG had to look natural and real. "You couldn't have that one mo- ment of getting pulled out to reveal the big effect," he says. "Sometimes you show off too much, but here, our work was part of the show. [e CG] felt nicely integrated and woven into the shots." When asked what their initial reaction was when Suskin first approached them with his concept, Gross, Hance, and Bre- dereck all broke out in a laugh, as they had done with Suskin, though this time the chuckling reflected their pride in a job well executed. "ey really did want something cool for this big return to the area, and our first response was, 'Okay, a full digital island, I think we can do that.' en there was a big interval of, 'Wow, this is a huge undertak- ing,' " says Hance. Bredereck had similar feelings, realizing that a natural landscape means infinite detail. So for him, he felt a mixture of shock and challenge. "In the 11 years I have worked in this business, this was definitely one of my most challenging assignments due to the scene's content and the time frame we had to work within," Bredereck says. Chances are good, though, that there will be more Lost challenges to come, as the producers and directors undoubtedly will continue to shock the audience with twisting and turning stories before the se- ries ends next year. n Karen Moltenbrey is the chief editor for Computer Graphics World. The plane's landing is shown from a number of POVs, though the artists avoided using any camera angles that would have been impossible to achieve in real life.

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