TRON: Legacy – behind the visual effects

This article originally appeared in IF Magazine #139 (Feb-March 2011).

Almost three decades ago, unknown storyteller Steve Lisberger wrote and directed a movie that will have a lasting impact on our generation. Released in 1982, TRON became an institution and its effects were considered “groundbreaking” in the industry.

It was a major motion picture first, blending in 70mm live-action, computer graphics and hand-drawn animation. In keeping with groundbreaking effects is its successor, TRON: Legacy.

“I think we’ve certainly tried to live up to that legacy of that first film and make this thing look every bit as cool – if not cooler – for a modern audience,” Academy Award-winning visual effects supervisor Eric Barba tells IF from Venice, California.

“We’ve certainly pushed the technology – in our work with Clu and with Jeff Bridges [who plays both Kevin Flynn and Clu] in creating something that’s never been done before.”

The Disney stereoscopic blockbuster, with a budget of reportedly $US170 million, is a high-tech adventure thrill-ride set in a digital world, and featured VFX work from Barba’s company Digital Domain (as the primary vendor) and partners Mr X, Ollin Studio, Prime Focus, Whiskytree and Prana Studios.

Barba, who picked up a shiny gold Oscar in 2008 for his work on Brad Pitt flick The Curious Case of Benjamin Button, was the overall VFX supervisor on the film which made $3.37 million in its opening weekend at the Aussie box office in late-2010.

DD was involved right from the beginning and helped get the movie greenlit after a proof-of-concept test was shown to network executives – and the general public – at Comic Con in 2008. “I was brought on very early – even before some of the producers and department heads were brought on – and immediately had to start planning and breaking things down and figuring out how we were going to do this in the time that we had,” says Barba, who was new to working in stereo as was TRON: Legacy director Joseph Kosinski – who both previously worked together on a 2006 Gears of War Xbox commercial.

It was certainly not going to be an easy feat, blending in live-action and photorealistic computer animation that hadn’t been seen before.

The story itself focuses on Sam Flynn (Garrett Hedlund) – the tech-savvy son of Kevin. Kevin has been missing for 20 years and Sam embarks on a journey to discover his father’s whereabouts and gets pulled into the digital grid where Kevin has been trapped. However now it has become far more dangerous than ever before.

Clu 2.0 was created to help Kevin and the other program Tron to build a perfect virtual world, however Clu turns to the darkside in his attempt to take over. Due to many vendors working on the film, Barba says they needed to be careful in making sure that it still looked the same throughout the 125-minute movie.

“It needed to be a cohesive piece and so I am proud of what we’ve done to work with those other partners and share as much technology as possible and work with them to keep this movie as a whole,” he says, adding it was a very “daunting” project. It may not be the first TRON movie but it created a number of firsts – the first 3D movie shot on 35mm lenses and full-35mm chip cameras, the first to create molded costumes using digital sculpture exclusively and the first to make extensive use of self-illuminated costumes.

But it was one other first that proved the hardest – TRON: Legacy was the first 3D film to integrate a fully-digital head and body to create a younger version of an actor – this time, Oscar-winning veteran Bridges.

“And then you say ‘oh and by the way it’s an American icon actor that we’re doing’ – people run away from you screaming,” Barba says with a laugh. “Definitely the Clu character was by far the biggest challenge because it’s never been done before.”

It was even more complex than changing Pitt’s appearance in The Curious Case of Benjamin Button due to the filmmakers wanting Bridges at about 35-years-of age – when the actor starred in Against All Odds. DD used dozens of photos of Bridges, now aged 61, when he was in his 30s in order to create a 3D digital version – a digital “facelift”, while a silicon mold was built from the actor’s face.

Bridges then performed a number of facial movements that were recorded on camera and immediately computerised in 3D – the older Bridges was controlling the digital performance of the “younger” Bridges. When he acted as Clu, he wore a custom carbon-fiber helmet that had four extremely small lipstick cameras pointed at his face. Dozens of dots on his face acted as reference points for the computer.

The information sent to the computer made it possible to instruct the digital head to speak and display emotions in the exact same way Bridges would on set. This allowed him to interact with others in the scene and it was the first time in movie history that a helmet-mounted camera was used in live-action.

For the live-action sequences of the younger Bridges, they used body double John Reardon. DD provided just over half of the VFX shots in the film (880 of 1565) and Clu accounted for 160.

VFX company Prime Focus was brought on last, starting work in March 2010, and contributed 120 shots – or about 13 minutes – to the film which ranged from entirely full-CG environments “that you can see from miles and miles and miles to a few interior shots”, explains their digital effects supervisor Jon Cowley. “But for the most part, the live-action component was maybe 15 per cent of the shots and the other 85 per cent of the work was total computer-generated environments – so it was big things we had to create over big periods of time over big distances,” Cowley tells IF from Vancouver, Canada.

The team of about 60 brought the End of the Line club and Tron City to life – by using extensive re-projections of digital matte paintings combined with 3D geometry – and created the massive Solar Sailer ship (and its environments). Prime Focus visual effects supervisor Chris Harvey, who worked with Cowley, says the team created a lot of volumetrics just to fill the stereo volume and in doing so, created a very “immersive” environment.

“We put lots of little subtleties and detail on the deep background and to me it felt like a very complete sort of environment that you got to be a part of,” Harvey says. Prime Focus relied heavily on Terragen as the backbone for all of their extensive stereo cloud environments.

“We used it primarily for the clouds and the volumetrics because we really had to create a huge volume of atmosphere so there was a lot of technology that we had to write in so we could deal with stereo,” Harvey says, who worked with Terragen developer Matt Fairclough who custom-coded the software due to the film’s requirements.

One of the hardest shots the company, which recently did work on the latest Chronicles of Narnia instalment, had to do was the scene where the Solar Sailer comes up from under the bottom of the city. “The camera does a full 180-degree sweep of it and now is looking in the opposite direction out into the vast outlands… it was fully-CG, super close to camera and a full 180-degree span of the world so you basically saw everything, so creating things like that were hard,” Harvey reflects.

“We had fluid effects trailing off the Solar Sailer to make it feel like it was interacting with that atmosphere. The Solar Sailer itself had to be created and rendered and some of the frames were upwards of 30 hours a frame just because it was a full frame and then you’ve got the left and right eye to do, and all the environment and the landscape looking in the other direction as well so it was a lot of work.”

Cowley adds: “We had some sweeping shots that even without those, all the vehicles were very reflective so you still had to generate what’s underneath the camera, behind the camera and everything else and of course TRON being as art-directed as it was, that definitely played a big role in it as well.”

Although mainly working with Barba, Harvey says working with Kosinski was interesting because he had such a strong visual effects background and he understood the art of what the vendors were doing.

With offices in both Vancouver and LA, Prime Focus’ software toolkit included Maya, Nuke, V-Ray and Terragen. “It was incredibly challenging, it was the hardest thing we’ve ever done and audiences seem to really enjoy it,” Barba adds.