Belajar animasi 3D tidak cukup hanya sekedar belajar menggunakan software animasi 3D. Kita perlu memahami proses pembuatan film animasi. Pengetahuan ini akan sangat membantu mengintegrasikan pekerjaan kita dengan pekerjaan dari tim yang lain. Tulisan di bawah ini mungkin bisa memberi gambaran bagaimana proses pembuatan film animasi itu berlangsung:
By Matt Hurwitz
Dec 3, 2004, 22:45
Ah, quiet suburban life. That’s what Bob Parr, the former Mr. Incredible, and his superhero family wanted, right? Not quite. In Walt Disney Pictures/Pixar Animation Studios’ latest animated feature, Bob (voiced by Craig T. Nelson), his wife (Holly Hunter) and their three super-kids are brought back to active duty due to the misdeeds of an old nemesis, Syndrome (Jason Lee), and his fellow evil-doer, Frozone (Samuel L. Jackson).
Pixar–whose roster of groundbreaking computer-animated films includes Toy Story (the first all-CG feature film), A Bug’s Life, Toy Story 2, Monsters, Inc. and Finding Nemo–stretched its home-grown technology further for its latest feature venture. The Incredibles marks Pixar’s first foray into animated human protagonists, as opposed to animals or toys, and will showcase technical advancements in rendering photorealistic CG hair, both long and stubbly. Also on the list of firsts: The Incredibles is Director Brad Bird’s Pixar debut, and Bird (The Simpsons, King of the Hill, The Iron Giant) is the first Pixar director to be recruited from outside the company. (He joined the company in 2000, after the Warner Bros. release of The Iron Giant.)
Rick Sayre, supervising technical director for The Incredibles, explains that the production pipeline varies for each Pixar film project. “It’s very specific to the way we work and to our software. Even the department structure varies from film to film.”
The supervising technical director is responsible for setting up that pipeline and the accompanying departmental structure, and deciding in what ways the company’s proprietary software and procedures will be pushed–or identifying any third-party software that will be required to do the job. “Then, once the show is up and running, I ride shotgun with the director, helping him negotiate the production process.”
Computer-animated feature films go through the same four stages as animated and live-action films: development, preproduction, production and post. In the development phase, storyboards are drawn based on a text treatment of the film to serve as the blueprint for the action and dialogue. For The Incredibles, Pixar story artists then created “story reels” to depict writer/director Brad Bird’s script. It was in these reels that the timing of sequences was first addressed and fine-tuned.
“In a typical animated film, the storyboard is only about the story. It’s like an illustrated script,” explains Sayre. “It shows the emotional interaction between characters, but there’s very little to do with camera, camera moves or composition. Brad’s storyboards, or story reels, are essentially like an animatic. They’re very specific, with 3D camera moves and the beginnings of effects.”
Story reels for The Incredibles were created using a new combination of technology for Pixar. Working in Adobe Photoshop, story artists drew scenes on Wacom Technology Cintiq LCD tablets instead of first drawing on paper and scanning those drawings in for manipulation in the computer.
“It saves that step of drawing, cleaning up and scanning. And with the Cintiq tablets, as the artist’s pen touches the tablet, the image appears on the tablet screen–rather than the whole hand-eye coordination issue of drawing with your hand while having to look up at a screen to see what you’re drawing. This was the first time they could get back to a drawing process that they were really familiar with.” Finished drawings were then treated in Adobe After Effects, to apply any camera movement or rough effects that needed to appear in the reels.
The Character Team
After the storyboards and reels are completed, the animation process begins, though not before a few preparatory steps are accomplished. The characters to be animated must first be created in the digital world. This process, which entails character sculpting, rigging and shading, is handled by a character team comprising technical directors and artists.
Basic character design is first worked out via physically sculpting a maquette figure of each character based on illustrations from the art department. While for past feature projects, such as Monsters, Inc. and Finding Nemo, Pixar artists would have scanned the maquette into the computer using a touch digitizer (accomplished by drawing a grid onto the figure and identifying each grid point in 3D space using a pen-like digitizing instrument), a different process was applied for The Incredibles. In a manner similar to the revised illustration-to-reel process, Pixar artists omitted the step of scanning their previsualization maquettes into the modeling system.
“This time we did it entirely without digitizing,” says Sayre. “We had a small team–two people–of digital sculptors. They literally just looked at the maquettes, talked to the head animators, the director and character designers, and sculpted directly into the machine” using Alias Maya software. “We’ve always had the opinion that 3D scanning is valuable if you’re trying to match something directly, like tracing. But there are plenty of artists who don’t need that step. A really good artist can just draw.”
The characters are then rigged using Pixar’s proprietary rigging software. Rigging a character entails putting in the bones, joints and controls that enable a character to be choreographed. Rigging defines the ways in which a character moves when animated and encompasses everything from simple limb motion to facial expression.
“This film was a big departure for us because it’s all about humans, as opposed to animals or toys,” says Sayre. “We had to almost completely overhaul the character rigging process to come up with a system that was more anatomically based, with bones, muscles and skin. You want the audience to feel like the characters are, say, being put in jeopardy, and the subtleties of how skin and bones move relative to each other help accomplish that.” Not to say there’s no hint of cartooniness. “Nobody’s going to mistake them for real humans. They don’t look like anybody you’ve ever seen.”
Once the characters are modeled and rigged, they’re shaded. Shading defines the way the surface of an object or character responds to light, both in terms of color and texture. “A good analogy is the difference between human skin and plastic. They have might the same color, but the human skin is going to have light scattering around inside it, whereas plastic will have light bouncing directly off of it.”
Clothing and Hair
While the digital sculpting, rigging and shading of characters was handled by the character team, another group of artists focused on modeling the characters’ clothing and hair. “We actually had to tailor the clothing,” notes Sayre. “The difference between an ill-fitting suit and a well-fitting suit is how it’s tailored. It’s quite a challenge when you have a character who, earlier in the film, is a trim Mr. Incredible, and then later, he’s an aging superhero with a big gut.”
Pixar clothing simulation artists first visualized the Incredibles wardrobe items using off-the-shelf commercial tailoring/patterning software, then brought these models into Maya for pixel manipulation by the company’s proprietary plug-in suite. The wardrobe models then moved into Pixar’s simulation software.
Animators may or may not have the clothing design completed before they begin their character work–and it’s not required unless the character is to have several costume changes. “Even in that case, you don’t actually need to have the costumes completely figured out before you begin animating, but from a production flow, there are a lot of incentives to have the basics of what clothes the characters are going to be wearing buttoned down before you get into production. For a character such as the intriguing Mirage, for instance, you’ll need to know if she’s wearing a dress or a pant suit in a shot because it affects the way she’s going to be able to walk,” explains Sayre.
The final prep step is layout, the animation equivalent of blocking a shot. The layout crew choreographs the characters and uses a virtual camera to create shots that capture the emotion and story point of each scene. Layout often produces multiple versions of shots to provide the editorial department with choices for cutting the scene for maximum storytelling effect. “The layout artists break down how long each shot will take, working closely with the editorial department. They determine basic things like where the camera will be in a shot, if and how it will move, what characters are in the shot, and, if so, how they will move, very broadly, relative to each other.”
Once layout is complete and the scene has been cut, the final version is released to animation. These artists animate the characters by making use of the work of their predecessors in the production chain. “The animators don’t have to deal with all of the chewing gum and bailing wire details that the technical directors do. They’re able to see the characters in a much higher-level interface. Their interface is more on the level of, ‘Here are the characters, and here are some controls that I can grab and manipulate,'” explains Sayre. “It’s quite an achievement that we’ve gotten it so that we’re doing skin and muscle and bone with high-level controls they can actually see. They don’t have to just work in skeletons or cut-ups. The skin will be in the same place it will be when we render it out at film quality.”
One of the systems responsible for providing the animators such control is the arrangement of Pixar’s computer processing and storage systems into a Model Farm, Image Farm and Render Farm. The Model Farm, a collection of Network Appliance FAS960 filers, contains all of the intellectual property–created in the steps described prior to animation–to generate the components that make up each frame or object. Pixar artists have called this collection of modeling data a “digital backlot.” The Image Farm is a pool of storage containing the completed image frames.
A third area, the Render Farm, actually generates those completed frames, pulling together the information from the Model Farm in a process referred to as rendering. The Render Farm consists of 1,024 Intel Xeon processors inside eight RackSaver BladeRack supercomputing clusters running Pixar’s RenderMan software. The Render Farm features two terabytes of memory and 60 terabytes of disk space.
“The Render Farm is a room full of about 2400 CPUs that just crunch away. [The artists] beat so incredibly on these things–almost 0.25 million NFS operations a second–they would absolutely be destroyed” if precautions weren’t taken. To ensure their supercomputing clusters aren’t overloaded by sheer number of operations requested of them, DNFS caches sit between the Render Farm and the Model Farm filers. Accessing a volume of 3D imagery via DNFS cache reduces the amount of traffic to the server, allows artists faster access to the imagery and, therefore, decreases render times.
During animation, the digital artists access the intellectual property (the characters’ shading, textures, etc.) using a collection of proprietary dynamic shared objects (DSO) in combination with the RenderMan shading language. The data is compiled quickly, allowing the textures to be represented without having to utilize the resources that would be required during complete rendering. This process allows the animators to get a sense of how the characters will appear when finally rendered while still allowing them to manipulate characters easily during the animation stage.
After character animation is finished, several other steps take place to complete the scenes. “You have to remember, in animation, everything is production designed. If there’s a can of soda in the scene, an artist has to design it. They’re actually modeled and then shaded so that they can be set-dressed and the final set can be built.”
Simulation teams make sure the simulated physics of hair and clothing resemble the physics of the real world. Effects artists also get to work, adding effects animation to both objects and characters, if effects are part of the personality or movement in a given scene. The Syndrome character, for example, has the ability to capture another character and move them around. “That’s an effect that moves, but the motion of that effect was actually done by an effects artist, almost as an algorithmic animation,” says Sayre. “Effects artists essentially design digital contraptions to produce those effects.”
The effort actually follows in the steps of classic cel animation, which also employed the work of effects animators. “We actually had one artist who had previously drawn completely hand-animated 2D effects for the former Sullivan/Bluth Studios, for both live-action and animated feature films. He was so well versed in effects animation that he was sculpting lightning bolts in 3D in the computer. It was amazing.”
The Directors of Photography
Computer animation also utilizes the talents of another artist, who works under a title common to live-action film work: director of photography. “Like in live action, the DP orchestrates for the crew the process of placing lighting in the set.” The Incredibles actually had three DPs: Janet Lucroy, who concentrated on lighting, Andy Jimenez, who concentrated on camera, and Patrick Lin, who focused on the layout and composition aspect of the camera. The animation DP’s background must be a varied one. “Janet, for instance, actually has a painting, fine art background, as well as a CG background. Because these films are so heavily art directed, heaving a strong art background is crucial.”
The sets are lit in a phase called master lighting. Using “digital light,” scenes are lit in a manner similar to stage lighting. Key, fill and bounce lights and room ambience are defined and used to enhance the mood and emotion of each scene. During the shot lighting phase, which takes place after animation is completed, lighting is finessed specific to how a character moves within a shot. “The DPs have many of the standard tools available that a DP would have on a set. We have the equivalents of filters, obies, flags, barns, etc.,” explains Sayre.
Animation is reviewed in a process that, again, borrows from the classic animation period. The director and supervising animators view work in progress through occasional walk-throughs, visiting individual artists’ workstations. Animation sequences are viewed in dailies to ascertain the current state of a scene or sequence. The team views footage on a color-calibrated CRT monitor as well as with widescreen projection to assure the accuracy of color decisions.
Sets and props are reviewed in a process called a “sweatbox,” a term borrowed from the classic animation era of Walt Disney Studios. (Many of the Pixar artists came to Pixar from Disney, after all.) “All of the department heads jam into the office of the editor, and if there are any problems, you’ve got all of the right people there to hash it out right then.” A much smaller group of people–the department heads, the director and the producer–assembles in the studio’s largest screening room, with its 2K DLP digital cinema projector, and views shots to be finalized.
In addition, film dailies are screened, though not to the extent as in previous projects. “Previous to Finding Nemo, film dailies were an important part of the process, but now they’re really just something for me and the DP. The DP is concerned with color contrast and creative issues, while I’m mostly concerned with making sure everything looks as good as it possibly can on film. All of the finals and approvals come from watching sequences digitally projected in our main theater.”
While the computer animation field still draws on the process of its cel animation heritage, to some degree, it has evolved many of its own disciplines, with specialists now required for things never imagined in those days. Sayre says, “I’m sort of an old-timer. Back when I started, there wasn’t coursework in computer animation or anything like that. It’s been really fascinating to see this industry evolve.”