Tippett Studio is back handling the wolves, under the supervision of Phil Tippett  and Eric Leven. But instead of the anthropomorphized protectors from New Moon , they are more believably animalistic. Fortunately, Tippett met the challenge by applying a new fur growth system developed for the upcoming Cats and Dogs: The Revenge of Kitty Galore. This replaced their customary black-and-white map technique.
"I describe it as a compositing package with a node-based system where you plug lead nodes together the same way you would in a Shake or Nuke  project," Leven explains. "So by building a node-based tree you determine how much fur is grown by calculating length, width and curliness.
"We have a base layer of fur that grows out of that and then another layer of fur that grows when interpolated by RenderMan  between the pre-grown hairs, which is something we've never done before. Those hairs are not as controllable, but you get a much richer and denser look, still using the same amount of memory footprint."
Meanwhile, Image Engine came on board as a result of their District 9  work to apply their own gritty aesthetic to the "historic wolves" sequence that tells the origin story in flashback.
"David Slade told us that he wanted to add a gritty realism to the Twilight  world," says Jon Cowley, Image Engine's visual effects supervisor. "What was nice was that it was a vignette, an action sequence, similar to the kind of work we have done previously. The other mandate was that they wanted a photorealistic look. What we were told was that these were not humans in a wolf's body but wolves in a wolf's body. So we tried to get away from animation and caricature.
"We were given the opportunity to get into some new creature design and try a new spin: they're a little more battered and gangly; a little more lean and mean. We went with more of a neutral brownish color palette; slight changes to the face and proportions; beefing them up with bigger shoulders. A little different but they still had to come across as these 1,500-lb, massive creatures."
"For our muscle systems, we used Maya muscles to get all of the underlying dynamics going on, and we used nCloth as a cloth simulation on top of that so we could muscles sliding underneath and skin and the fur dynamics to happen on top of that.
"We were tasked with developing three historical wolves and were also awarded a ravine chase sequence where we had to put in two contemporary wolves as well, Quil and Embry. That was interesting because we had to closely match the wolves that Tippett created."
Image Engine was also allowed to experiment with "vampire speed," turning them into super athletes rather than superheroes. "Our comp department did a lot of rotoscoping and separating characters and time warping part of their performances so that they're moving very, very quickly but grounded in the physics of our world," Cowley says. "What was done before was in-camera and somewhat hidden. We were tasked with trying to do something that was front and center. A lot of things were shot at high speed -- 48fps, 72 fps -- so we had the incremental footage in between to speed up and slow down those performances."
They settled on expanding the "diamond skin" motif developed by Prime Focus. "Their muscles, bones, fatty tissues all start to turn to this crystal, diamond-like material when they turn," Cowley continues. "And there's still blood flowing through their veins and some human anatomy remains. We tried to get that to morph over time to these hard crystalline surfaces. That's what gives the vampires their super strength. So we developed a look based on crystal samples (ruby and quartz) that we discussed with David.
"We then built the shaders and geometry to get that particular look. One of the other mandates is that these vampires are beautiful and elegant. We started from the skin and worked all the way inside the body with this crystal motif. We couldn't get gory. Crystal was a great solution for finding that ripped apart, beautiful look."
Bill Desowitz is senior editor of AWN & VFXWorld.