Issue link: https://digital.copcomm.com/i/17873
n n n n Visual Effects the sequence and think they shot a slow-mo- tion plate,” Franklin says. “But it wouldn’t have been possible. You can’t strap a delicate high-speed camera onto a speeding vehicle. Muhittin Bilginer [technical director] created layers and layers of slow-motion CG rain fall- ing down, hitting the street, and splashing.” A Dneg team again added slow-motion CG rain to the end of the shot as the van drops off a bridge and plunges into the river below. For this shot, the artists created the rain us- ing Maya particles, and compositor Scott Pritchard supervised the layering of digital and practical rain elements into the sequence. Because all the people inside the van except for the driver are dreaming another dream, and because the physics of one layer affect the next, in the second dream layer (which takes place in a hotel), the walls and ceiling move as the van leans around the corner and then freefalls off the bridge. Borrowing an idea from techniques used to create zero gravity inside a spaceship for Stan- And then, with the help of New Deal Studios, they blew it all up. New Deal built a 45-foot-tall miniature and, working from Knapp’s previs, exploded their version of the set and the moun- tain. “Tey replicated the action from the previs and took it further,” Franklin says. “And then we added CG bits and more buildings in the back- ground. It was the best of both worlds.” Inside this dream, the characters snooze their way into a deeper dream, the final level, Limbo. How Low Can You Go? Limbo is where dreamers end up if the dream traps them, and at this point in the film, Cobb and Ariadne wash up on the shores of Limbo. Cobb was there before, trapped with his wife for 50 years. Both architects by trade, while there they constructed a modern city, but Cobb has been away for hundreds of dream years, and this city, constructed deep in his mind, is falling apart. “Chris [Nolan] wanted a city collapsing into the sea, and he wanted it to be completely technique that worked. Using reference pho- tos of glaciers, Boyle built polygonal models to capture the basic shape, and then created space-filling algorithms that used basic build- ing blocks. “It was like building a glacier with giant Legos,” Franklin says. “We added a rule to the procedural system to insert streets and intersections, and another set of rules to vary the width of streets and buildings based on the shape of the glacier. Trough this iterative process, we ended up with a complex cityscape that had recognizable shapes taken from archi- tectural history, but had a crumbling, decaying feel because it was inspired by the shape of the glacier.” Ten, with the help of a procedural destruction system implemented within Side Effects’ Houdini, they collapsed the buildings and destroyed the city. For a final encounter between Cobb and the ghost of his wife, Dneg created a giant storm that sweeps across the city using the studio’s Squirt fluid dynamics system. Te blizzard that tears through the streets and rips build- ley Kubrick’s 2001, Corbould’s team built gi- ant rotating sets. “Tey built an 80-foot-long section of corridor that could rotate at eight feet per minute to create a tilting bar and ho- tel room,” Franklin says. “It was staggering to watch and a testament to the immense power of doing effects in camera.” As for postproduc- tion work, the artists’ main task was painting out wires, replacing backgrounds, and adding floating debris. In addition, for shots that take place later on this dream level, the Dneg team put CG faces onto stunt performers. Below the hotel level, the dreamscape moves outside, to the top of a Canadian mountain, where the art department built a set at 8000 feet and filming took place in freezing tem- peratures. CG artist Vanessa Boyce led a team that built a CG model of the set and then ex- tended it, adding storms and blizzards using 3D particle and fluid dynamics. Compositing lead Richard Reed’s team fit the model and the effects into plate photography. 16 August/September 2010 At left, Double Negative artists created the decomposing city by procedurally stacking building blocks inside the shape of a glacier and then crumbled it with a procedural destruction system. At right, the studio sent a blizzard raging through the dream city using its proprietary fluid dynamics system called Squirt. unique,” Franklin relays. Dneg art director Gurel Mehmet created concept drawings of a sea wash- ing over a city, of a city embedded in a glacier, a sea in city streets, and more, but the drawings didn’t match what Nolan envisioned. “Te art department tried, as well,” Franklin adds, “but nothing hit the mark. So Chris concluded that we couldn’t get there with concept art. Te idea had to evolve in a complex fashion.” Franklin remembered that when he was in art school, he would create steel sculptures by cutting pieces of metal that he’d stick together with spot welds. “Using this process, I’d arrive at an end result, a sculpture built from short sections of welded steel that had aspects of a drawing. But this process is the complete an- tithesis of digital visual effects.” Franklin sat with Boyle and lighting su- pervisor Bruno Baron, and they developed a ings apart echoes shots of the collapsing café in Paris at the beginning of the film. “We are creating outlandish imagery from deep inside the mind with the clarity of a lucid dream,” Franklin says. “Visual effects are an integral part of that. But the most significant thing in this film is not that we are pushing the boundaries of new science, it’s the develop- ment of the art of visual effects. We’re reaching a level of sophistication in which filmmakers can treat visual effects as another camera. Tey can say, ‘I’d like to shoot this,’ and we can film it for them through visual effects.” Film anything, in fact, that a filmmaker can dream of. n Barbara Robertson is an award-winning writer and a contributing editor for Computer Graphics World. She can be reached at BarbaraRR@comcast.net.