Issue link: https://digital.copcomm.com/i/711516
16 cgw j u ly . a u g u s t 2 0 1 6 interpolate across tus. We also don't want a small number of hairs to move a large number of tus." "If you look at hair simulation in some films, you see too much uniformity," Bowline adds. "Hair moves together too much be- cause you can simulate only so many things. But, we can move the dial on a shot-by-shot basis. If a creature is close to the camera, we want to simulate every single guide in that frame. We want high-resolution collisions and heterogeneous behavior. But, we don't want the simulation artist to have to build a different setup. With the procedural system, we can get to the right population and the right number of hairs." L I G H T C R A F T At the end, fitting believable humanoid characters into live-action plates depends on the skill of compositing artists who rely on the ability of lighting artists to match the light in the photographed plates. To help these artists, ILM came up with a new technique called LightCra for creating a 3D representation of the lighting in the live-ac- tion environment. "Normally when we capture lighting in an environment, we use a sphere," Smith says. "With LightCra, we take one sphere like normal, and then also take one a foot higher so we have a little parallax between them. Using that parallax, we can look at an image and decide how far away each piece is." Thus, the lighting artists could use the toolset to construct lights at different depths. "LightCra is just a toolset to push for- ward our ability to get a more true represen- tation of where the lights are on set and how far away they are," Smith says. "This is espe- cially important when we have a character moving through an environment." Although developed originally for Warcra, the film's long postproduction schedule gave crews on other films moving through ILM a chance to use and improve that technique and others. Star Wars: Episode 7 used Light- Cra and pushed it even further, according to Smith. And, The Revenant. "We delivered the bulk of Warcra a year ago, in April 2015," Smith says. "I've been on Warcra-related things since 2013. Up to [April 2015], it had been in production for a year and a half, and filming had happened six to eight months before." Aer delivering Warcra in 2015, Smith moved onto The Revenant, and received an Oscar nomination for his work supervising ILM's visual effects on that film. Then, War- cra came back. "We had an opportunity to do another delivery, so we took some shots we wanted to improve to support the story more clean- ly," he says. Small improvements. For exam- ple, they added more green to characters affected by fel magic that were near a fire, to single them out. Green or not, tusked and heavy-hand- ed or not, in the end, the tools ILM developed for Warcraft helped the artists create and perform characters so believ- able that critics don't dwell on the fact that they're digital or CG, but instead laud the performances of the actors that ILM motion-captured. For the invisible visual effects artists, that's high praise indeed. ■ HYBRIDE MANAGED THE CROWD SIMULATIONS FOR WARCRAFT USING IN-HOUSE TOOLS. Crowds For the crowd simulation in Warcra, Industrial Light & Magic partnered with Hybride. "They used their in-house tools and [Soimage] XSI," says Jason Smith, visual effects supervisor, "and worked with a huge library of actions captured at Animatrik's motion-capture studio. They could quickly randomize the char- acters with, say, half one clan and half the other, or maybe 10 percent female and 90 percent male, and populate huge battle scenes quickly with hundreds of characters." Barbara Robertson (BarbaraRR@comcast.net) is an award-winning writer and a contributing editor for CGW.