The Making of Toy Story

Home , Buzz Lightyear, Loren Carpenter, Pixar Image Computer, Sheriff Woody, Skywalker Sound, Tin Toy

The Making of ToyStory

Mark Henne, Hal Hickel, Ewan Johnson, and Sonoko Konishi Pixar Animation Studios 1001 W. Cutting Blvd. Point Richmond, CA 94804 [email protected], [email protected]

Abstract Many elements were vital in making the film, including character and story development, unique software tools, the Toy Story is the first full length feature film produced abilities of voice actors and animators, and the imaginations entirely using the technology of computer animation. The of artists and designers. Technical artists showed their abil- main characters, Sheriff Woody and Space Ranger Buzz ity to create beautiful models, lighting and surfaces, and Lightyear; are toys that come to life when humans aren’t managerskept the pipeline flowing. Lest we claim all the around. Their story is one of rivalry challenges, teamwork credit, much is owed to the Walt Disney Company, Pixar’s and redemption. partner and mentor. Making this film required four years of effort, from writ- ing the story and script, to illustrated storyboards, through modeling, animation, lighting, rendering, and@lming. This 2. History paper examines various processes involved in producing the film. Severalcore members of Pixar began work as part of Lu- casfilm Ltd., starting with Ed Catmull in 1979. He attracted 1. Introduction John Lasseter from Disney, and also collected Bill Reeves, Loren Carpenter, Tom Porter, Eben Ostby, and others to Before Toy Story was made, the contribution of computer build the technical team. In 1986, Steven P. Jobs arranged animation to feature films was measuredin secondsor min- for the team to split from Lucasfilm and form Pixar. utes. The challenge of this project was to produce an entire Numerous researchpapers have been produced by these feature film showing a complete world created digitally, to researchersand others at Pixar, including advances in ray populate it with characters seeming to act of their own vo- tracing and motion blur [2], rendering architecture [l], lition and experience, and render it with the colors, shapes, shadowcasting [7], image cornpositing [4], particle systems and textures of a believable stylized reality. [5], and animation [3] [6]. The result is a film that couldn’t have been made any other way. When Sheriff Woody and Buzz Lightyear come Through the years, Pixar’s ventures into the graphics to life, they have a sense of three dimensional form that world have included the Pixar Image Computer, Render- solidifies their existence, confirming our suspicions about man software rendering products, joint technical develop- the secret lives of toys. The techniques used can create ment of Disney’s Computer Animated Production System motion so detailed and fluid that a character’s emotion is (CAPS), several short films including Tin Toy, which won clearly visible, all in an enticing world with the uncanny an Academy Award in 1988, and the production of various ability to appear simultaneously both real and unreal. television commercials. In the world of Andy’s room, Buzz is the new kid on By 1991 the company felt ready to take on a larger ani- the block, blithely unaware of the the threat he poses to mation project, and looked to Disney for support in creating Woody’s position in society as Andy’s favorite toy. Their a television special program. Instead of a TV project, the conflict causesa distraction at a dangeroustime, when they deal blossomedinto talks of a full-length feature film, bring- are left behind at the gas station and faced with the prospect ing to reality the long-time dream of Pixar’s founders. In of being lost toys. Only through teamwork and friendship 1995, Toy Story came to market, providing the cornerstone can they make it back home. for Pixar’s future.

1063-6390/96 $5.00 0 1996 IEEE 463 Proceedings of COMPCON ‘96

Proceedings of the COMPCON Spring '96 - 41st IEEE International Computer Conference 1063-6390/96 $10.00 © 1996 IEEE 3. Overview is used to create a story board, where one or more illustrations are drawn in pencil for each shot of the film. A shot Creating a fully computer-animated film requires bor- is a continuous camera take, which in Toy Story might last rowing techniques from both live action film production from a half second to almost thirty seconds. Story board and traditionally animated filmmaking, as well as the inven- drawings are scannedfor use in an Avid Media Composer, tion of new techniques. In the new world, old-style cartoon where they are mixed with temporary dialogue and sound character model sheetsare expandedand merged with archi- effects, producing story reels. tectural designs to produce three dimensional models in the Oncethe story reels are created,an iterative loop is begun. computer. Sets and props are constructed once and can be The length of each shot is determined, and story pacing and reused in any number of shots, and the time-tested methods camera angles can be judged. Weaknessesmight mean of camera motion and real life film lighting are mimicked the addition or deletion of a shot, a change in dialogue, or in the simulated world. Unlike the production of a live ac- something more extensive. The creative development loop tion film, both old and new animated films rely on a greater doesn’t end until desired changes can no longer fit in the amount of pre-planning, as it is very expensive to create schedule. In order to gain some perspective, outside test multiple takes or to cut out finished shots. audiencesare shown work-in-progress reels at a point when There are three main phasesin the creation of a computer- the story is first considered to be “finished.” animated film: creative development, production, and post- production. 4.1. Artistic Design During creative development a story concept is built into a treatment, followed by a screenplay and story boards. The development of the story provides the locations and Working with the editorial department, the story boards are descriptions of the action, but ignores the details of color, recorded onto video as story reels and combined with voice lighting, and design. Character designs are explored early, recordings. and as the personalities from the story emerge changes are Once the creative development has sufficiently matured, made in design. The selection of voice talent also influences production can begin. This includes art design, model- this design. ing, and shot layout, and continues with animation, lighting The colors, shapes,and sizes of the various sets are cho- and rendering. As shots are approved in rendering, they sen to emphasizethe emotions and actions being portrayed. are recorded onto film. The editorial department continues Andy’s room is very bright, safe and with soothing col- its work of inserting new material from various stages of ors. Lighting conditions vary to simulate times throughout production into the story reel, updating as more becomes the day, with the dramatic sunset lighting taking place as available. Woody schemesto knock Buzz behind the desk. In Sid’s As significant sequencesof rendered film become avail- room, dank and hidden corners dominate a black lit prison. Notice however, that the lighting keeps pace with Buzz’s able, they can be sent on to the post-production phase. Here sound effects are added and mixed with a musical score, and reawakening. The rain falls during the night as he wallows in self-abasement,but morning light comes and the showers color corrected copies of the finished print can be made. end as he realizes his worth and positive impact on others. Since the creation of an animated film is so sequential in The artists also prepare design documents for every nature, efficient management of the pipeline is crucial. A model created. Each item, from the hubcaps on the cars suitable inventory is required especially during the stages to the mailbox in Sid’s yard, is thought out, sketched and di- of the production phase, so that the order of attack can be mensioned. The packet of model drawings is sent to a group optimized. of model builders, but when the time comes to add texture, dirt and scratches,the artists will once again be summoned. 4. Creative Development Reference photos and magazine clippings may supple- ment illustrations in the model packet, and pointers to movie Before any film can be made, a story is needed. Toy clips might be needed to clarify what is or is not wanted in Story was conceived and written at Pixar, and developed in some visual effects animation. For some models, especially a collaborative effort with a team from Walt Disney Feature faces, a clay sculpture is made to be used on a magnetic field Animation. It all starts with a story concept, the basic digitizing table. premise of the movie. This premise is expandedinto what’s called a treatment or outline, where the fundamental story 5. Production points are identified and sequencesare outlined, Further refinement of the treatment produces a screen- The production phase of a film must wait until the cre- play, complete with dialogue and scene descriptions. This ative development reaches an acceptable level of maturity.

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Proceedings of the COMPCON Spring '96 - 41st IEEE International Computer Conference 1063-6390/96 $10.00 © 1996 IEEE Becausethe creation of eachshot will require so much work, and choreographthe camera movement relative to the ob- it’s important to have the story fleshedout as completely as jects in the shot. The transition from pencil to computer can possible beforehand. Occasionally a shot may get cut or often be difficult, as the realities of scaleand perspectivere- changedafter it hasbeen produced in finished form, but that veal liberties taken in the sketches.The overall motion of a is rare given the total number of shots. charactermay also be blocked out during layout, especially Models are producedfrom design packetscreated by the if suchmotion must coordinatewith a moving camera.Great Art Department, and then placed in sets and dispersedinto care was taken to use establishedtechniques governing the the proper shots by the Layout Department. Layout feeds use of cameramotion. Too many productions in computer the animators,who worry only aboutmotion but not color or animation move the camerasimply becauseit ’s possible. lighting. Before shots can progressfrom animation to light- Members of the Layout group have many details to re- ing, shadersare written and assignedto models. Shaders member. Toy Story is composedof more than 1,500 shots, are the surface textural description of an object, includ- and logical consistencymust be maintained. The collection ing its color, reflectivity, transparency,patterning, dirt, and of objects into setsis one way to maintain order, and a shot scratches. databaseassists in the task. The visual flow between shots The Lighting Team is given shots that have been ani- is also a factor, and sometimes adjustmentsare necessary mated, and createslight sources,shadows, and reflections. to make things work. The audienceshould never notice the Once the lighting is finalized for a shot, it is blessedfor film cameracuts; they should always feel natural. rendering at a resolution of 1536 scanlines. 5.3. Animation 5.1. Modeling The role of the Modeling and Layout groupsis to provide The model builders translate the model packet designs the animatorswith shots that are ready for animation. The directly itito the computer. Some models are createdusing setsare alreadyprovided, the cameraview defined, and gross commercial design software from Alias, and then translated level motion blocked out. When an animator first visits a into the in-house Model language. Model is a module of shot, they can even put on their headphonesand hear the Marionette, Pixar’s proprietary production software envi- audio track as the shot plays on their computer. ronment. Pixar employs an unusual strategy when it comes to the Model builders are responsible for more than realizing animation staff. Most other companysin the computer ani- the static description of an object. Taking into accountthe mation industry look for people with a certain level of com- importance of the object, the builder must de&de on the set puter graphics literacy, but the attitude at Pixar is to locate of controls over its articulation. For example, both Slinky individuals who really know animation. They come from Dog and the Jack-in-the-Box mutant toy have a coil spring, a variety of other media, including traditional ccl anima- but Slinky’s has a more complex interface becauseit must tion, stop motion, clay, and evensand. Producing animation do so much more. The controls of a model, known as avars, involvesprojecting personality,expressing nuance and emo- are describedprocedurally in the Model language. tion, using timing, staging,anticipation and follow-through. Some models can be completed in hours, while others In short, animation is acting by proxy. take weeks. Woody has 712 avars,counting 212 in his face The traditional hand-drawnway of producing animation alone. Muscular control is provided in detail over various is for an animator to begin by drawing key poses for each parts of the lips, cheeks, and eyebrows. Special software character in a shot, roughing out the extremes and flow tools exist to assistin the creation of flexible characters. of the motion. The key poses derive from an exposure As modelsare constructed,review sessionsare scheduled sheet, a breakdown of the action in the shot, and a dope with the director, art director, and animation supervisors. sheet, a written indication of where the words and stress Proportion, scale,detailing, and control setsare checkedfor fall in the dialogue. A cleanup artist then inherits the shot, propriety. Complex models may spend time in animation redrawing the key poseswhile making sure they conform to testing before being releasedwidely. the establishedlook of the characters. After adding some in-between drawings, they pass on the work to animation 5.2. Layout assistants,who complete drawings for each of 24 frames in a secondof film. Tbe processrequires up to thirty people As an inventory of models accumulates,the work of the to complete a single shot; by contrast, all of Toy Story was Layout Department starts to grow. It is in Layout that the completedby thirty animators. film takes its first step from the sketchesof story boards to Animation on computer is completedthrough a seriesof the three dimensional world of computer graphics. Working refinements. The rough motion inherited from Layout at with Editorial, members of the Layout Departmentposition the start is refined and adjusted to include broad gestures

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Proceedings of the COMPCON Spring '96 - 41st IEEE International Computer Conference 1063-6390/96 $10.00 © 1996 IEEE necessaryto convey the intended message. Unlike tradi- the shader determineshow deeply the character intersects tional animation, where key posesare specifiedfor an entire the bed and perturbs the surface downward matching the character, animators on a computer can structure overlap- shapeof the foot. This could have been done by animating ping key frames for different parts of the body at different physical deformationsof the bed, but it would have required frames in the shot. As the animation takes shape,more sub- building a highly complex representationof the bedspread, tle secondaryand tertiary motions can be layered abovethe especiallyto achievethe folds emanatingfrom the footprint. primary action, which are then completedby facial gestures. As more objects are given surface attributes, a library Another benefit of working on a computer is that the ani- of useful shadersand functions begins to emerge. Special mators neednot concernthemselves with consistentdrawing utilities are provided for projecting dirt and other texture styles and proportions. At any point in time, an animator paintings. can seeand hear their shot running in real time. 5.5. Lighting 5.4. Shading When a sequenceenters lighting, the placement of the Models enter the shading department devoid of visual cameraand the animation are complete. The master lighter character. It is the shading department’sjob to settle on a beginsby meeting with the director andart director to discuss look and realize it through the technology and capabilities the sequence.Together they identify essentialstory points of Render-man.Working from a shaderpacket assembled from the animation, color script, and story reels; they may by the art department,the model is analyzed. What type of also discussrelevant technical issues. With these as guides, object is it? Is it old or new? Is the material reflective, or the masterlighter defineskey lights in the set to establishthe does it just carry a sheen? This processis straightforward, basic lighting environment for the sequence. Once this is since the shader packet contains much of the information in place, individual shots can be assignedto other members as written notes and photo reference. The first step is to of the lighting team. Their job is to take the initial lighting assign basic surface colors for the object. Afterward, the schemeand refine it for their given areas. shaderauthor separatesthe surfacedetails into layers, each The work done during lighting can be likened to ink layer a specializedprocedure which addsto the final surface and paint in traditional animation. Drawings done by the appearance. animatorsare painted on clear acetateeels and filled in with The shaderon Sid’s window ledge is a prime exampleof carefully chosen colors. Dark and light areas are defined layering. In order to provide the withered, old look that has to help lead the eye to the action. The difference is that beenpainted multiple times, it is divided into more than five in computer animation the visual complexity that can be layers: a layer for the wood grain, a hand painted layer to achievedis so much higher than in traditional means. indicate where the base coat of paint lies, another painted Members of the lighting teams need to be concerned layer to describewhere this paint is chipped and scratched, about lighting continuity, color, and brightness. Given the more layers of paint for color, and finally, a layer of dirt and extreme freedom of altering lighting conditions on a per- scratchesto provide the agedaffect. shot basis, it is tempting to beautify individual shots at the In addition to describing the surface layers, the light- expenseof consistencyacross a sequence. ing model is encoded in the shader. The lighting model Since Toy Story was producedin three dimensional com- describesa surface’s shininess and reaction to lights, and puter graphics, setting up lights becomes very similar to may be as simple as plastic or as complex as satin. At its the sametask on a live filming stage. A key light provides completed stage, a shaderwill have anywhere from ten to the primary high-contrast contribution, added to a softer two hundred lines of code to accuratelydescribe its surface fill light, and with rim lights to help define the shapeand under a variety of lighting conditions. produce additional highlights. The shadersin Toy Story also made extensiveuse of dis- Even so, physical correctnessin lighting is often less placement shaders, which describe physical variations in important than aesthetics. To achievethis, the behavior of the surface. Grass, for example, requires a massive amount light sources and surfaces are often cheated. Marionette and of geometric detail and is ill suited to a polygonal or sur- Rendermanare very flexible in the kind of lighting they can face patch description. As a shader, however, it requires provide. This includes the ability to alter the shape,softness significantly less data to describeits shape,form, and vari- and extent of a light, or to allow the light to shine only ation. It also has the advantageof knowing how large the on specific objects. Shadowscan be placed independently grasspatches ’ projection becomesin screenspace, and can of their casting lights, or reflections can be altered to suit automatically vary the amount of detail. an artistic purpose. Throughout the lighting process, the Another example of a displacementshader is the com- challengeis to make the sceneslook real, but with the visual forter on Andy’s bed. For each step taken by a character, richnessthat is not necessarilylimited by realism,

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Proceedings of the COMPCON Spring '96 - 41st IEEE International Computer Conference 1063-6390/96 $10.00 © 1996 IEEE Sinceeach shot is on-screenonly briefly, its effectiveness in a project the size of Toy Story, reliable data management dependson how quickly the viewer’s eye is led to the key is a must. story elements.Lighting is one of our most effectivetools for The first elementof Ringmasteris its relational database, achievingthis. By the useof lights, imagesare painted with which is constantly updatedwith all aspectsof production. areasof light and dark, cool and warmth, and hardnessand It maintains inventories of models, textures, and images. softness. The interplay of these elementsis indispensable Using this database,Ringmaster routes rendering requests in bringing out the focal points of the story. to available machines on the RenderFhn and maintains appropriate status information. Once a rendering job is 5.6.Visual Effects completed, Ringmaster continues the process by invoking the cornpositingof layers to produce a finished image. There were a relatively small number of shots in Toy Ringmaster also works with the Accom digital video Story that had requirements outside the normal pipeline. recorders and the film recording software and hardware, These shots had various visual effects animation on top of helping to provide a more fully automatedenvironment. the other action, some examplesof which are rain, sparks, smoke, exhaustand explosions. 5.8. Production Hardware The visual effects animation falls outside the expertise of the animatorsbecause achieving the proper look involves too much technical ability. Thoseproducing the effects need Each animatorand technical artist is provided with a Sili- to havea solid understandingof all phasesof the pipeline, as con Graphicsworkstation on their desk, typically an Indigo2 everything from modeling to animation to shaderwriting to loaded with between96 and 256 megabytesof memory and lighting must be addressed,often in an experimentalloop. up to 2 gigabytesof local disk space.Every animator is also The visual effects were often done after the main scene given a dedicatedBandit frame store device, and those pro- lighting, but just prior to submissionfor film rendering. ducing high quality images can record them on one of four Accom digital video recorders. Two Solitaire film recorders 5.7. Production Software transfer electronic images onto 35mm film. Film is viewed in the company screeningroom, complete with couchesand the central commandreclining lounge chair. Pixar uses mostly proprietary software for it’s productions, with the exception of some modeling done in Alias An arrangementwith Sun Microsystems provided a Ren- and digital painting done with Amazon. derFann of over 300 processorson the local network, com- Marionette is Pixar’s software systemfor modeling, ani- bined with severalSilicon GraphicsRenderFam machines. mation and lighting for computer animation. Marionette is As personal workstations begin to sit idle, they are drawn the primary software tool used by every animator and tech- into the pool of batch processors. nical director at Pixar. In contrast to many commercially Disk resources are equally vast, with a DiskFam of available animation systemswhich are designedto address around260 gigabytesof on-line storagecontaining approx- product design, corporate logo graphics or cinematic spe- imately 140,000digital image files. cial effects, Marionette has beendesigned and optimized for charactermodeling and animation. 6. Post-Production The animation subsystemof Marionette is designedto be accessibleto userswitl&nited computerexperience, allow- ing Pixar to hire an animator basedentirely on artistic skill. The last phase of producing Toy Story occurred after At the sametime, Marionette haspowerful functional foun- the film left Pixar. At Skywalker Sound, sound effects dations that allow a moretechnically proficient user to take were added and mixed with the final musical score. Final complete advantage of the system. In Marionette, mod- prints are made of the film after adjusting to get consistent els are programs in a specialized programming language. color acrossall the prints. These are then distributed to the A technical artist can use the power and flexibility of this theaters. languageto createmodels that move or deform in very com- Pixar’s post-production is simpler than post-production plex ways, or can build control structures into the model of a live-action film, which requires more significant edit- that make it easier or faster to animate. Most animation ing. In most live-action films, many hours of film are shot, systemsrepresent models as setsof data separatefrom their and the film is then significantly edited and re-edited in the animation controls. Changing the paradigm makesit easier post-production phase to create a feature film. Pixar, like to tackle a project as large as a feature film. other animation studios, edits the film throughout the entire Pixar also has a data organization system in place called creative developmentand production process. Thus post- Ringmaster. Given the number of shots,models, and people processinginvolves only final editing.

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The day is now here when it is feasible and cost effec- tive to produce a feature length motion picture entirely on computers. The commercial success of Toy Story confirms the message long proclaimed by Pixar; that the important elements of filrnmaking are story and character, and that people will come to see a quality film.

References

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