Issue link: https://digital.copcomm.com/i/259450
SHORT FILM 32 ■ CGW Ja n u a r y / Fe b ru a r y 2 014 Magical Realism Computer Graphics Pioneer and Pixar Cofounder Alvy Ray Smith once stated that "reality is just a convenient measure of complexity." It fell to "The Blue Umbrella" production crew to create that complexity. "We had a very high bar," says Chris Burrows, supervising technical director. "Saschka [Unseld] was really interested in the photorealistic look, so everything fell under that umbrella, so to speak. It required scene complexity in textures and in the geometry itself." Burrows describes a wide shot in which Blue floats through the air above a city stretching into infinity as the camera pans from left to right. "That shot has a million and a half pieces of geometry in it," Burrows says. "A million and a half individual models. Most, though, had 400,000." The team started with a set that was six city blocks long and had six intersections, built in rough, low resolution. "We used that to find our locations," Unseld says. "Once we placed the action and the camera and decided how shallow the depth of field would be, we gave it a rough lighting pass and detailed it out more. We worked on everything in layers to not have the work spiral out of control." To determine which buildings needed geometric detail and which could be textured cubes, the team borrowed a working method from visual effects studios. "We implemented shot dailies," Burrows says. "That was a new process for Pixar. Every morning the entire crew would look at the shots at whatever state they were in. That provided the context for making decisions. The level of detail was es- sentially a manual process after that, but one of the things we did with "The Blue Umbrella" was test out [The Foundry's] Katana." With Katana, the artists could look at the scene and reduce complexity where possible before sending it to the renderer. "The first time we raytraced a scene, we ran out of memory on a 64 gb machine," Burrows says. "So we did a lot of work to optimize and lighten up the geometry." The animated faces, however, remained geometrically complex. "We see 14," Unseld says. "And there are another three or four that don't have active roles, like the building we called Anna that still has a face but isn't fea- tured. You can discover it if you watch the film a couple times." Unseld gave each a name – the triplet awnings, the traffic lights, the church, and so forth. "Some are high-energy creatures," Unseld says. "Some are in their '90s and have jaggy movement. The mailbox is Carsten, the rainspout is Greta, and the electric outlet cover, the first one you see, is Lisa. It felt right to name them." An outlet cover on the street near Unseld's home in San Francisco inspired the face he calls "Lisa." In the film, the magic begins when she winks. "Lisa probably had 20,000 [polygonal] faces," Burrows says. "Saschka went out with a tape measure and took high-reso- lution photographs of the concrete plate in San Francisco. We had to model that dense geometry and then put high-resolu- tion textures on top of that. The others weren't that complex, but we definitely pushed the bounds." For textures, the shading artists manipulated photographs and then mixed in procedural and painted textures. "That brought a richness to the detail," Burrows says. "It would be hard to paint nice concrete by hand, but we didn't want it to look like 'here's a photo, there's a photo.'" Scene Complexity Unaware of the magic surrounding them, crowds of people under the sea of gray umbrellas walked on the sidewalks, and cars traveled through the rain-soaked streets, all of which filled the city with more detail and energy. "The city feels alive," Unseld says. Animation cycles applied to the people and cars kept them moving, and pre-canned cloth simulations for the clothes on those close to camera added to the visual complexity. "We realized that in the wider shots, we had people down the street who would hold up in close-up shots," Burrows says. "They even had buttons on their jackets. But, we didn't need to model clothes on people at a distance. We just painted the skin to look like they were wearing clothes. When they get even farther, you just see umbrellas rocking back and forth down the street." To move the people, the crew used the crowd pipeline devel- oped for Monsters University. Animators created walk cycles and drew paths on the sidewalks; the crowd system placed the digital people on the paths and applied the animated cycles. "We cached the walk cycles into our internal file format, and then the simulator would pick cycles to match certain speeds," Burrows says. The crowds didn't need to be agents with ■ THE BLUE AND RED STARS of the film stand out among the sea of gray umbrellas.