When Gore Verbinski was on location in the Caribbean filming Pirates of the Caribbean, he told visual effects supervisor John Knoll, animation supervisor Hal Hickel and the rest of the Industrial Light & Magic team there to capture the performances of Johnny Depp, Bill Nighy and others, that he’d like to make an animated feature. “We were in the middle of the craziness of back to back Pirates,” remembers Hickel. “He liked the idea of not having to deal with the logistics of filming in the Caribbean. As we now know, animated features have interesting logistics, too.”
    They now know because Verbinski was as good as his word. Rango, the animated feature he wrote, directed and produced, his first, has hit the silver screen. It’s a spaghetti western, modeled after films by Sergio Leone, and set in a desert. The stars are animals, animals that behave like humans, designed by Crash McCreery, who was a creature concept artist for Pirates of the Caribbean: Dead Man’s Chest. Also joining Verbinski’s Rango posse were Johnny Depp, who voices the chameleon Rango, Bill Nighy who gives voice to the villain Rattlesnake Jake, and the crew of 325 people at ILM.
Verbinski called Knoll and Hickel to talk over the idea during the summer of 2007. He pitched the story to them in February 2008, and the following September, ILM modelers began sculpting the characters. “John and I were comfortable working with Gore,” Hickel says. “And it was really exciting. The story didn’t feel like anything in the animated feature mainstream.”
In fact, nothing much about Rango fits the animated feature mainstream, including the production. “This show is a big departure,” says Tim Alexander, visual effects supervisors. “Our language was that of a live action film.”

We Don’t Need No Stinkin’ Color Script
Because the entire crew, starting at the top with the director, was familiar with live action filmmaking and visual effects, but not animation, the pipeline that ILM adopted was a hybrid, incorporating some elements typically found in an animation studio, but not all. Sometimes, that was intentional. Sometimes the changes happened on the fly.
    An example: Even though a team of layout artists at ILM created camera moves that matched story reels, a typical process for animated features, Verbinski often took advantage of ILM’s motion capture stage to frame the shots a bit differently. That became possible because, rather than create environments by painting and then projecting 2D images into a 3D space as they had done for years to create environments, the digimatte artists quickly learned that they needed to keep the environments live in 3D as long as possible. By working in full 3D, they created simple representations of the huge expanses early in the process – an undulating ground plane, for example, with a repeated fractal pattern, buttes with rough textures, and a sky cyclorama – and then fine tuned the details later. The simple representation was good enough for animation. “We didn’t have any shot-specific details,” says Andy Proctor, digital matte supervisor. “But, we had story points; we knew what features we needed.”
And, Verbinski, Alexander, and Knoll move rocks, cactus and so forth around, and do location scouting within the environments. When Verbinski visited ILM, he would a Cintique tablet to move around within the 3D set, change lenses, change focus, and reframe shots. Often with him on these location scouts were cinematographer Roger Deakins, who has received nine Oscar nominations [True Grit, No Country for Old Men, Shawshank Redemption, and others] and camera operator Martin Schaer.
A second example: During pre-production on most animated films, an art director creates a color script, which is usually a series of paintings that show the mood and emotional content of the story from beginning to end. Lighting artists, who take on that half of a cinematographer’s role, refer to this script. ILM didn’t have a color script.
“We were making a live action movie that happened to be an animated film,” Alexander says. “Gore [Verbinski] doesn’t use a color script. Directors of photography don’t use color scripts. And, we had never made a color script. So, we lit the scenes by feeling them out.”
For example, John Bell, ILM’s art director, who joined the project after McCreery had already designed most of landscapes, buildings and characters for the film helped set the mood of a nighttime scene early in the film. “The story was pretty well baked by the time I got involved, but they weren’t sure yet how to treat the nighttime shots during a highway sequence,” Bell says. “Crash didn’t want typical blue light. So, I pulled out a book about the western painter Frederick Remington who painted dusty, deep green skies. Crash said, “That’s the mood I want to see.” He knew the scene before had a lot of red, so taking it from dramatic reds and oranges to teal, the opposite color on the color wheel, was a great contrast when Rango is wandering through the desert.”
Rango, like all the stars of this animated feature, is an animal. He’s a chameleon in appearance and, we soon learn, by nature as well. He also one of the few characters who doesn’t look beat up, dried up, and mangy. As the story begins, Rango is inside a terrarium traveling in the back of a car across the desert. When the terrarium tumbles out of the car, Rango and his only companion, a wind-up plastic goldfish, are free. Lost. Thirsty. But, free. Fortunately, a young woman, well, a pretty young lizard actually, named Beans happens by, bumping along in a wagon filled with empty bottles that’s pulled by a javelina. She takes us to Dirt, a collection of ramshackle buildings that rise from the dusty horizon like a mirage and look suspiciously like a set for a western movie. Until you look more closely. Some of the buildings in Dirt are made of wood, but one is an old gasoline can that the animals turned into the saloon. “A lot of the objects in the town are things discarded in the desert,” says Steve Walton, viewpaint supervisor, who led a team of texture artists. “Tin cans, bottles.”
Rango soon meets many of the town’s strange-looking citizens. All told, Rango has 130 of unique characters from which ILM added around 50 variations.  With the exception of Rango, Beans, Priscilla, a big-eye rat voiced by Abigail Breslin, who is obsessed with death, and the mayor’s secretary Angelique, a fox, all the characters are mangy, nasty, dirty, ugly things. “This is a dry environment,” says model supervisor Geoff Campbell. “There’s no water. The characters don’t get to spend much time grooming.”

Crafty Characters
Usually, on animated features, sculptors create clay maquettes from the 2D designs. ILM decided instead to follow the approach that had always worked for visual effects – roughing out models in Maya and then adding details and shapes for facial expressions in the studio’s own Zeno with added surface details in ZBrush. It was a mistake. To create all the characters and assets the film needed, the team of around 12 modelers had a three-week window per character. But the modelers found themselves waiting for approvals on minor details – the character’s teeth, for example – when they hadn’t yet nailed the overall look. “We needed maquettes,” Campbell says. So, they changed the process. But, rather than sculpt clay models, they quickly – in three days per character – created maquettes in ZBrush, put the characters on turntables and got the sign offs they needed for proportions and quality.
    Because McCreery was still developing the designs for Rango and Beans, though, they followed a separate route for these characters. “Frank Gravatt worked with Crash to figure out Rango’s model,” Campbell says. “And we pulled in Jung Seung Hong, who did Davy Jones, to do the facial library for Rango. Rango has less technical complexity than Davy Jones, because he doesn’t have tentacles, but he had his own complexity. There’s lot that goes into anthropomorphizing a character, especially one with eye sockets so big and the distance between his lips and eyes so small. And his mouth is so wide, when he smiles, he has only a little cheek. How do you show a terse sneer when you don’t have room?”
    Beans had a different problem. “We had artwork, but she lacked that look of a heroine,” Campbell says. “Gore didn’t want her to be beautiful, but he wanted an inner beauty to come through the character. Crash spent a lot of time here working with us directly, sculpting in ZBrush, and we spent time in Los Angeles.”
How do you sculpt inner beauty? “It’s kind of subjective,” Campbell says. “The corner of her mouth curled in a certain way. The look in her eyes. She has huge eyes, so we had to balance her mouth and little chin and make her attractive but still a crazy-looking lizard.”
For facial animation, modelers created shapes based on the FACS coding system for ILM’s proprietary FEZ technology. “With the FEZ system, for every way that an animator could dial in the facial expressions, there was an automatic cleanup process,” says James Tooley, creature development supervisor. “Sometimes we built a two-way system. Animators might dial in a shape that caused a jaw rotation, or rotate the jaw and the shapes would move automatically.”
For each character, the rigging team, which works in Maya, created a unique GUI, one of the few rigging innovations for this film. “That was the only thing out of the box that the animators asked for,” Tooley says.

Big Hat No Cattle
In addition to the characters’ form and faces, the modelers also created costumes, viewpainters added textures, and Tooley’s group made their clothes and hair move. “We were building these characters in their own world, so they didn’t have to match reality, and their faces were not from the natural world, but Gore and Crash made it clear that the town of Dirt had a level of complexity close to realism,” Campbell says. “So, their clothing had to be absolutely photorealistic.”
    Thus, modelers paid attention to details down to the seams, texture painters added salt stains and sweat stains, and the Tooley’s simulation team added wrinkles. All the humanoid characters wear clothes, in fact, several layers of clothing with gun belts, and so forth, but Rango was especially complex.
“Normally, we have template software so we can use the same control system for all the bipeds,” Tooley says. “But, Rango had 13 different costume variations. And, all the costumes had a dynamic simulation of some type. We had a control system in one of his hats so the animators could bend it; the hat had to change shape to fit the mood of the sequence. ”
Tooley has been leading teams that have simulated multiple layers of clothing since the first Pirates film, so the studio has well-developed techniques. Typically, they simulate an under layer first and then work out, simulating each in turn. “We try not to do all the layers at the same time because they interact so much that if something goes wrong, they all go wrong,” he says.
One technique they’ve developed gives them specific control over the simulation. “We used ‘tacks’ first for [Star Wars] Episode I,” Tooley says. “We hard coded a tack for one of the Gungun costumes into the software. If cv number such and such was being processed, do this. Now, we do that mostly with artistic controls, by painting surfaces.” That made it possible for the simulation team to keep suspenders in place and moving correctly with the rest of a costume, for example.
“If you look at a lot of animated features, you won’t see a lot of clothing dynamically simulated,” Tooley says. “Usually it’s deformed with wrinkle maps or shape changed. I think that’s partly to keep it from drawing attention away from the animation. But, we wanted to create the feeling of an old west environment. There’s wind in a lot of sequences and you see that wind on the costumes. We’re so familiar with having to do photorealistic costumes, we didn’t even think about it. That’s just what we do.”
Typically the simulation team sent the cloth through first and then the hair. ILM’s Maya-based hair system uses guide hairs interpolated into the thousands of strands needed to create a mangy cat or grungy gopher. Modelers build the initial guide hairs, the creature development artists do the simulations, and the look development technical directors clump the interpolated hair into tufts. Combined, all the characters in the movie have over 38.5 million hairs, which ILM points out, is more hair than 257 people have on their heads.
    Bean’s hair was most interesting. The lovely lizard has six long curls on the back of her head. “We did all kinds of crazy stuff to make her look her best,” Tooley says. “She’s such a major character.” The crazy stuff included running a single strand through the center of each curl that would drive joints for enveloping, and using tetrahedronal cages to move the curls without uncurling them.
One of the few animals not a humanoid was a hawk, and Tooley’s crew simulated its feathers, using algorithms to keep each feather the proper width and length within deformations for medium shots and full simulations on individual feathers for close ups. But, when the hawk crashes through the buildings in town as it chases after Rango, if the big bird was behind dust and debris or motion blurred the crew used the deformation algorithm even for close-ups.

Down and Dirt-y
To break the building apart, the team used ILM’s Fracture program, created initially to destroy a planet in Star Trek 2009, and Mayhem, a system created for Episode II. “As long as the fractured geometry looked good, I didn’t care if they used Houdini, Maya, or whatever,” Tooley says. “They just had to make sure the textures adhered to the broken geometry, and the geometry held together without seaming problems.” A system based on underlying algorithms in Stanford University’s Physbam system handled the rigid body dynamics.
Because water – that is, the lack of water – drives the plot, which makes the film a kind of cross between Chinatown and The Good, The Bad, and the Ugly, everything, from the characters to the town, needed to look dry and hot.
“The texture artists are remarkable,” Bell says. “They fine tuned the surfaces using bump, displacement, specular maps until you’d look at something and know that thing had baked in the sun for decades.” But although the buildings look aged, dusty, and muted, they weren’t always that way.
The texture artists that painted the 40 buildings and 1000 props began by making everything look new. “I’d start with everything brightly colored, then get in my head what starts the weathering, and bring it down naturally,” Walton says. “There’s an overall weathered feel to the scenes, but all the colors are all there. We photographed wood, dirt, metal, and other kinds of imagery to create a level of realism.”
“ There’s a tendency for CG to be clean and pristine,” Walton adds. “With sharp, perfect edges. On this film, the desire was to have it look nasty. We didn’t get nasty enough for a while. But, we knew we got it when Gore said, ‘Now clean it up. It looks horrible.”
Also helping give the location a hot and arid quality were heat ripples that shimmered in the desert, and a dusty atmosphere. A team of 17 effects artists led by Raul Essig, who had been a digital artist on the third Pirates film, At World’s End, and a sequence supervisor for Star Trek, created the dust and dirt, as well as other simulations.
“We used Plume, which we originally created for Air Bender for a number of shots because it has a nice aesthetic,” Essig says. “It can create dust with thin tendril features which look beautiful. But, that’s not always what Gore wanted. It wasn’t grungy. So we did most of the work with dust using a traditional volume rendering atmospheric technique. And in some shots we had passes of both to get the best of both worlds.” The resulting layers of atmospheric passes with haze in the distance and dust swirling past the camera gave the environment the look that Gore wanted. But, it wasn’t easy.
“If we were doing a couple shots, no big deal,” Essig says. “But when half the movie is outside in this dusty environment, and you have shots by the hundred, you have to get really creative to do an effect that is traditionally expensive.”
A particle simulation – whether from a fluid simulation or a standard particle simulation –  determines where the dust originates and lands, and then the renderer marches rays through a volume created from the particles, from the camera to the horizon. Sometimes, dust rises up from the ground plane. Sometimes, a generally dusty atmosphere drifts around.
“When a fluid simulation drove the particles, we had to treat it like a practical effect on a set because it’s real world physics,” Essig says. “With traditional particles, you tell them where to go and they follow along.”
To make the production possible, the crew created generic simulations with clouds of dust for the entire town. “We could pick up something from that simulation and render it directly,” Essig says. “We didn’t have to re-run a new simulation for every shot.
Plume also handled fire simulations, but for water, the crew relied on the two in-house system, one based on PLS (particle level set) and another on SPH (smoothed-particle hydrodynamics). “SPH is really good for small scale events like a splash of water,” Essig says. “Early on, we try to formulate a good plan of attack and think about what the best tool is for a shot. But, by the time you get to the shot, you might find that what’s wanted has changed. Watching the production progress is almost like watching a fluid sim. You might have an idea aobut what might or could or should happen, but often what does is a total surprise.”
That surprise pales, though, next to the surprise the audience will have when they see this film for the first time. From a three-owl Mariachi band, to the one-legged ostriche-like character, to the mangy bar cat, Rango is a totally unique visual experience. One that, perhaps, only a director, production designer, and production studio experienced in the art of visual effects could have bent, twisted, and shaped into being.