Man vs. Machine

With its intricate inner workings of hydraulic piston rods and gears, James Cameron's Terminator was an amazing feat of animatronic engineering in 1984. Produced on a B-movie budget of $6.4 million, the biomechanical cyborg was one of the most technically complex characters ever realized on film. Then, in the 1992 sequel Terminator 2, the world thrilled to the most groundbreaking marvel of CG animation it had ever seen in the mimetic polyalloy form of the T-1000. Recently, Zoic Studios made television history by using CGI to re-create the film series' awe-inspiring visual effects on a weekly basis for Terminator: The Sarah Connor Chronicles, further closing the gap between audience expectations for the two mediums.

Scripted by Josh Friedman, co-writer of the 2005 film adaptation of HG Wells' War of the Worlds, the new Fox series follows the events from T2. It stars Thomas Dekker as John Connor, Lena Headey as his mother, Sarah, and Summer Glau as Cameron Phillips, a female Terminator posing as a high school classmate who protects John. Sent back in time to kill John is a Terminator called Cromartie, a more robust and menacing version of the T-800 played by Arnold Schwarzenegger in the original films.

Throughout the series, Cromartie, a T-888 model, assumes the roles of various figures in John's life, including a substitute teacher who tries to shoot the boy when he states his name during morning roll call. When a blast from an energy rifle strips the flesh from his metal chassis, the T-888 enlists the aid of a scientist in formulating a protoplasm that will grow a new suit of skin. Once inside his new flesh, the Terminator kills the scientist and begins masquerading inside the faces of one of his patients and then as an FBI agent.

Pushing the TV Envelope
Pushing the special effects envelope has always been a trademark of Cameron's films. But, the famed director is quick to counter that his work is similar to that of David Lean, who made intimate character dramas set against spectacular backdrops. While TV has always excelled at intimacy, the real challenge for visual effects supervisor Jim Lima (a protÃÆ'Æ'©gÃÆ'Æ'© of both Cameron and Steven Spielberg) and effects supervisor Andrew Orloff and his team at Zoic Studios was to create that epic backdrop on the limited budget and time constraints of episodic TV. 

To meet that challenge, Lima and Orloff turned to Cameron's original 1984 film as a template on how to make the epic economical. "We pored laboriously over the original Terminator and T2, studying the T-800 endoskeleton and the way the surfaces interacted with the environment, especially since all that stuff, including the Hunter Killers [huge, antipersonnel combat tanks and planes], were done with miniatures, mechanical puppetry, and full-size props," says Orloff. "We wanted it all to look like the original designs and interact with the environment, as they do in the original movies."

In fact, Orloff even procured a master replica of the original Stan Winston chrome endoskeleton, a full-scale model that he kept at Zoic's Los Angeles offices, to be referenced by all the artists. "We could always be aware of every little detail, from the number and texture of the scratches, to the grunge smeared over it, to the way highlights interacted off surfaces."

Before shooting, Lima and Orloff work closely with Friedman and the executive producers during the treatment phase of every show, producing concept art and contributing to the script to ensure that the effects shots are technically feasible and within budget. Along with conceptual art and storyboards, Zoic's artists are constantly doing previs and durvis to ensure the shots come together.

"We pore over the script and talk about shot methodology and what's possible within the time and the constraints of the production," says Orloff. "We think of the best way to shoot something, and write down every element we need to get that day so we're prepared." That's important, he explains, because the Terminator and other Skynet machines are so reflective, requiring HDR surveying of the environments.

Building the T-888
For the new Terminator, Orloff says Lima "got deep into the philosophy of the technology," making structural modifications that resulted in a more muscular and meaner-looking endoskeleton than its predecessor. Specifically, Lima added a host of supporting structures throughout the body and bulked up the spine and the thighs. After analyzing both Winston's and Cameron's original sketches, it became apparent that, in order to make the frame more robust, the T-888 needed a less skeletal profile.

"Jim [Lima] was using a lot of references of high-carbon bike frames, like motorcross bikes, to guide his structural improvements and to make [the frame] look more battle-worthy and, in some ways, more high tech," says Orloff. Lima also added two more CPUs to the T-888's skull case, so in the event of a violent whack to the head, the machine can continue to function through a type of redundancy system.

Zoic Studios uses Auto­desk's Maya and NewTek's Light­Wave as the backbone of its production pipeline; both programs run on custom workstations driven by Nvidia 8800 GTS cards running Windows XP. Orloff cites LightWave's rapid radiosity simulation as being particularly invaluable for the pace of episodic TV. Maya's expressions and set-driven keys were also crucial, he says, for automating the mechanical movement of the individual gears, pistons, and rods involved in moving the cyborg's arms and legs.

For modeling the T-888, the artists used Maya and LightWave; they also worked with Luxology's Modo to create the skull, into which artists forged an overt scowl directly into the bone structure to make the fleshless face more expressive. To the same end, Lima designed a nose that adjusts slightly when it smells, and tooth sockets that can be refitted with human teeth. "Though we wanted greater expressivity, we obviously couldn't use blendshapes for a rigid model. Therefore, you'll also see a lot more eye movement, brows, and other distinguishing features modeled to make him look meaner."

Despite the complexity and intricacy of the model, with its many internal moving parts and three million-plus polygons, Zoic did not use separate models with differing levels of detail. "We used one model that's polygonal and subdivided based on the needs of each shot," says Orloff. "There is only one model, and that's never closed up. It has a level of detail that we obviously don't need subdivided as much for shots that are far away, but it's really important even in the long shots that you see all the inner workings because it's such an exposed character. The interior pieces are always laid bare and need to be working to keep the model 'alive.'"

Artists re-created the set lighting using a 360-degree HDR photography rig to generate reflection maps and image-based lighting maps, in addition to global illumination rigs.

The team rigged the skeleton in Maya using standard FK and IK switches, and added a battery of expressions to drive the animation of the gears and pistons and to ensure precise hip movement during walking or running. Animators crafted the T-888's performances through extensive hand animation and motion-capture sessions executed at the House of Moves in Los Angeles, which uses Autodesk's MotionBuilder and proprietary software to map the data to the skeleton.

In actuality, the group has two rigs for the T-888: one that's set up for motion-capture data and another that's set up for hand animation. The latter has all the traditional IK and FK switching, along with other rigging components, such as set-driven keys, to make hand animation easier. The mocap rig, on the other hand, has the joints aligned in a way that makes it easier to transfer the data.

Mechanized Motion
While the artists stayed true to the structural and textural properties of the original Terminator, they tried to avoid the staccato, puppetry movement inherent to the animatronic movement of Winston's T-800. Instead, they imbued the T-888 with a more fluid, primal motion characterized by an animal's heightened sense of awareness.

"We tried to smooth out his movements, make them a little more organic. There has to be a performance to his acting, not a technical re-creation of something they did in the original movies," says Orloff. "In fact, the stuntman gave us a Terminator training lesson in the motion-capture session for the pilot, showing us exactly how they all move in every situation-with or without skin. There's a certain methodic nature to it when they're out of their skin." As he points out, a Terminator has two types of movement: one for when his skin is on, which is designed to help him infiltrate and blend in; and another for when the skin is off, when there's no reason to blend in anymore. At that point, he can revert to a more efficient style of motion.

Of course, many scenes would require living tissue to cling to the metal skeleton or re-form over it. In a pivotal sequence, a fleshless Cromartie, disguised under some head wrapping and a long trench coat, teaches a scientist to formulate a protoplasm that will regenerate his skin. Cromartie enters the bathroom and disrobes to reveal the endoskeleton, and then immerses himself in a tub containing the substance, before emerging with a new skin. The scenes demanded close collaboration between Zoic and Robert Hall's crew of prosthetic makeup wizards at Almost Human Special Makeup EFX.

"Rob Hall saved the day," says Orloff. "In that sequence, after the Terminator comes out of the bathtub all fleshy, his eye is cut open and his Terminator eye is revealed. That was actually done with prosthetic makeup on an actor who was shot practically. We then composited CG pieces behind the prosthetic makeup." The group did that quite a bit for shots of the damaged Terminator, where the artists would matchmove pieces of prosthetic makeup and add CG metallic parts.

For tracking the camera, the prosthetics, and other live-action objects, Zoic uses both 2d3's Boujou and Andersson Technologies' SynthEyes. In fact, the shot of the naked T-888 composited into the cramped quarters of the bathroom is a marvel of reflection mapping and one of Orloff's proudest achievements thus far in the series. (It can be viewed at www.almosthuman.net.) 

Lighting & Reflection-Mapping
Of course, lighting and reflection-mapping a large, chrome-plated character to blend seamlessly with the live-action environment was an often migraine-inducing task. Artists painted the surfaces of the body using a combination of procedural maps built in LightWave and grunge maps made in Adobe's Photoshop.

To re-create the on-set lighting, Orloff and Lima built a 360-degree HDR photography rig to capture a panorama of the live-action sets. The rig employs a Nikon D200 digital SLR camera with a 10mm lens mounted on a rotating head, and takes nine exposures to obtain a 360-degree panorama for each environment. Zoic's artists then import the nine HDR exposures into PanoTools (a free suite of tools for assembling panoramic environments), stitching them into a 360-degree panel. This panel is used as a reflection map and an image-based lighting map in LightWave. Along with the image-based lighting maps in LightWave, Zoic uses global illumination rigs on the HDR spheres gathered on set.

"LightWave gives that radiosity look very quickly; we're able to use the actual image without having to run it through the LightGen plug-in any more," says Orloff.

Modelers built the new Terminator model in Maya and LightWave, using Modo to craft the skull.

 

True to the mythology of the films, all the machines and humans from the future arrive in present-day Los Angeles amidst a burst of wind, electrical sparks, and lightning-known as the "time-travel sphere." In Orloff's opinion, lightning generated from a software solution looks unnatural. Rather, he prefers the old-school approach of drawing the lightning by hand. Here, it was done with Autodesk's Flame and Combustion: Artists rotoscope it in frame by frame, drawing individual bolts of lightning as lines and animating them by hand, before applying a glow filter to give it that lightning look.

Zoic also had to stage several future battles between the humans and the machines. To do so, the group re-created the giant Hunter Killers (HKs), ground-based and aerial antipersonnel combat units that stalk the skies and battlefields. "The HKs are like hovering aerial enforcers that fly over post-judgment day Los Angeles," says Orloff. "They're the same vehicles we see in the flashbacks and flashforwards from the original movie." Zoic modeled them in Maya, and then hand-animated, textured, and rendered them in LightWave.

These scenes unfold within a completely digital environment or amid digital set extensions. Thus far, Zoic has created a total of eight virtual sets for the show. One features a futuristic Los Angeles with a view looking up to the Hollywood Hills, and another-for the HK battle-in which the live-action background, filmed on a backlot, is completely replaced by gutted buildings, raging fires, and debris fields. These digital sets combine 3D elements, generated in LightWave, and matte paintings done in Photoshop, Flame, and Combustion. Artists primarily used Maya to generate plumes of smoke, digital dust kicked up from the T-888's footfalls, and other particle effects, including the digital squibs that explode when the endoskeleton is peppered with gunfire. Later, they moved to Flame and Combustion for compositing and touch-ups.

Zoic's Well-Oiled Machine
Although Zoic is already a veteran of TV work, having completed ambitious effects for Battlestar Galactica and CSI, Zoic tailored its tools, production process, and pipeline for the rigorous schedule of The Sarah Connor Chronicles. The facility generated more than 400 visual effects for the two-part pilot alone, and between 30 and 300 effects shots per show there­after. To accelerate the turnaround of those shots, Zoic also developed Q-Ball, a proprietary translation software that not only allows artists to share models, textures, animations, particles, and dynamics data, but to work simultaneously on the same scene in both Maya and LightWave.

Placing the Terminator in the confined areas of a bathroom proved difficult. Caustic renders in LightWave helped with the reflection, making the addition of the CG more believable.

The bathroom scene unfolds in a very confined space, making it difficult to place the T-888, Orloff points out. "The [image-based lighting] and the HDR maps work really well, along with the lighting and the texturing. We also did caustic renders [in LightWave], so that the light that hits the reflective metallic surface is reflected and amplified back off the wall," he explains. "The modeling, animation, and compositing were intricate, especially with the one long shot looking directly at the T-888. It holds up to the photoreal standard of the show, and that's the most important thing: to be able to do a photoreal CG character of that complexity on a weekly basis."

For the big HK battle, the team only had a row of set dressing in front of the actors; the group had to replace the whole background with a post-apocalyptic Los Angeles and the hand-animated HK fighting the resistance soldiers. "Again, it had to be, and is completely, photorealistic, mapped with the image-based lighting and HDR maps we got from the set that day," Orloff says. "It's as far as any TV series has pushed the limits of production value and, in our case, in expanding the visual language of a film series."