Thomas J. McLean discovers how The Reaping offered Double Negative the opportunity to recreate two of the biblical plagues in present day: the locust swarm and the river of blood.
According to the Biblical tale of Exodus, God inflicted 10 plagues upon the Egyptians with a wave of the staff of Aaron or Moses. For London-based effects house Double Negative, recreating two of those plagues in present day for the Warner Bros.' horror film The Reaping (opening April 6) took considerably more time and effort.
Producer Joel Silver and director Stephen Hopkins signed on Richard Yuricich -- a visual-effects legend who worked on such ground-breaking films as 2001: A Space Odyssey, Silent Running and Blade Runner -- to supervise the visual effects work on the film.
Double Negative vfx producer Steve Garrad had worked with Yuricich on the first two Mission: Impossible films, as well as an aborted Danny Boyle project called 3000 Degrees. Garrad says Yuricich's mandate was to be as photorealistic as possible. "Richard's approach is completely driven by how would you actually photograph the event," he says. "For him, the desired imagery drives which software solution is chosen, not vice versa," he says.
Double Negative won the job of working on the locust swarm and the river of blood sequences after producing a test of the locusts using a particle-based approach. Garrad says they decided to stick with particles instead of upgrading to an artificial intelligence simulation to save time on the film's original schedule, which targeted a summer 2006 release.
"When the release date moved we all collectively breathed a sigh of relief," Garrad adds. "With the longer post schedule we were able to accommodate other types of shots apart from the two sequences we had originally been awarded. We ended up producing 213 shots for the film in the end."
Garrad and Double Negative's Ken McGaugh, the vfx supervisor, did their testing in July 2005 and visited the shooting location in Baton Rouge, Louisiana, in August 2005, just as Hurricane Katrina hit. Hurricane Rita followed a few weeks later, though neither storm caused more than minor damage to the location. Effects work began in earnest just before Christmas and took a year to complete. Garrad says 70 people worked on the crew, which was reduced to "a hard core of 25" when the release date changed. Seven people worked on the blood river, while 13 were devoted to the locust scene, with the rest doing some miscellaneous other shots.
The locust sequence required Double Negative to come up with ways to quickly populate scenes and realistically control the swarms of as many as a half-million bugs.
"With a swarm of insects there are too many of them to directly control them, so you're either taking a particle-based approach, or an A.I.-based approach," says Andrew Chapman, who oversaw the CG on the locust sequence, which comprised 75 finished shots. "In either case you're trying to direct these guys in a very indirect way, and that can be tricky, especially for people who aren't used to working that way."
Chapman and technical director Jakob Schmidt broke down the animation for the insects' movements into modular behaviors that could be easily altered and updated as the project progressed. They then created some tools to quickly populate scenes either by covering a surface, filling a wireframe volume or using a particle emitter.
Chapman created the particle system used on the film in-house and Maya was used for the CG. To keep the scenes as easy to manage as possible, the technical directors used simple cone and dot proxies instead of the full locust geometry to set up scenes, an approach that allowed them to see how the insects were moving but remaining lightweight. The dots and cones were automatically replaced with fully rendered and lighted geometries in RenderMan. The artists also had three levels of detail to choose from, with low-detail versions used in backgrounds and high-detail ones closer up.
For a few shots that required the locusts to not intersect with each other, Double Negative's proprietary dynamics engine, Dynamite, was used to create a layout.
Beyond the technical aspects, Double Negative also had to meet director Hopkins' vision that the insects be menacing, slightly creepy and that a few of the bugs have a non-realistic look.
"We had bright red and bright green locusts within the swarm of black and yellow locusts," explains Garrad. "They still made it into the shots, but their numbers were significantly less that the black and yellow variations."
The sequence required extra strong efforts from the rotoscopers and especially the tracking crews, who had to deal with swarms of locusts landing on characters and suffocating them. "To get useable bodytracks was a time intensive painstaking task and the only available answer was time and diligence," continues Garrad.
Chapman says the concept of those shots evolved from placing a few bugs on actors to doing thick coatings of insects that required the tracking to be very precise. "Without 3D scans of the actors, we had to take our generic human models and fit them as best we could, which sometimes involved keyframing the geometry shapes to match the outlines in each shot," he says. "Finally, the body tracks were animated using only the primary camera plates." PFTrack, boujou, 3D Equalizer and the in-house software DNphotofit were used for the tracking.
The second major sequence involved the river of blood, which Garrad suggests had to be done so it didn't look like they'd just changed the color of the water. The color also had to match from shot to shot. "The red palette we were using was actually out of gamut on the monitors, so the only way to ensure consistency was good old-fashioned film," he says.
Details were key in the sequence, ranging from making the blood look like it was lapping against the shore and trees, as well as adding digital frogs and debris. Most of the river was in 2D to save costs, with a few shots done in 3D to add viscosity and depth where needed, Garrad offers. The crew completed 59 shots for the final river sequence.
Compositing was done in Shake. An in-house program called Noodle was used for rotoscoping. The London-based crew kept in touch with Hopkins and Yuricich via phone and email, sending files back and forth for review via ftp.
Garrad and Chapman both are proud of the way the Double Negative crew performed in the face of hurricane and schedule changes. "It was great to see some of our more junior crew step up and deliver; we had some real stars," Chapman says.
Thomas J. McLean is a freelance journalist whose articles have appeared in Variety, Below the Line, Animation Magazine and Publishers Weekly. He writes a comic book blog for Variety.com called Bags and Boards, and is the author of Mutant Cinema: The X-Men Trilogy from Comics to Screen, forthcoming from Sequart.com Books.