Child's Play
Issue: Volume: 27 Issue: 9 (September 2004)

Child's Play

"Birthday Boy" is a timeless story set in a specific place and time—Korea in 1951. As the young protagonist of this nine-minute CG movie meanders home through a nearly empty town, we observe the bombed-out buildings and the ravaged landscape of a country at war. But we also see the delight on little Manuk's face as he finds a screw in the empty fuselage of a plane, or watches a stream of tanks roll by on the back of a transport train. The camera spends a lot of time on that face, which is at one moment keenly concentrating, at another seemingly devoid of thought. It's the face of any child at play. But Manuk's simple diversions take place against the backdrop of a war that will soon affect him much more than it already has.

"Birthday Boy," which was named Best Animated Short in the Computer Animation Festival at SIGGRAPH 2004, is the first 3D CG film from animator Sejong Park, a recent graduate of the Australian Film Television and Radio School, where he completed the project. (The film, incidentally, is also the first from the school to have earned the prestigious award at SIGGRAPH.)

The inspiration behind the movie, Park explains, was the desire to compare the innocence of childhood with the realities of wartime. "I wanted to tell the story of human life using animation," he says. "Life is not always fun; it includes both happy and sad times."

Park says that "Birthday Boy" is also a reflection of his childhood in Korea, where he was born and where he lived until he was 31. Though his relatives weren't involved in the war, "it is still recent history and very much alive in the Korean consciousness," he says.
The expressive face of the lead character in "Birthday Boy" was widened by animator Sejong Park to help achieve a stylized look.

Park also relates to Manuk's creativity and resourcefulness. In the film, the child crafts soldiers and other toys out of bits of metal that he finds on his rambles through the half-destroyed town. "I was never given any toys as a child and enjoyed making my own," he recalls. On moving to Australia, he was struck by how many presents children received for their birthdays. "This was a vast contrast to my own childhood experience. It was very different in Korea." Even so, "Birthday Boy" doesn't preach or deliver a heavy-handed message. The story proceeds at a deliberate and gentle pace, as we observe Manuk's interactions with his surreally disrupted world.

It's a story for which CG animation would seem to be the medium of choice rather than the medium of necessity. "Birthday Boy" doesn't have any chatty aliens or inanimate objects that spring to life. There are no otherworldly textures or blue fur. In fact, the film could theoretically have been shot with live actors, or made in 2D. But Park says that 3D software tools he learned to use at school made it possible for him to control the look and vision of the animation in a way he couldn't have otherwise.
Hand-painted mattes provided the backdrop for Manuk's bombed-out town (top left) and hand-painted textures gave a realistic look to his coat and cap (top and bottom right), as well as to the various metal objects that become his toys (bottom left).

To begin with, although Park was already a 2D animator and illustrator before he began work on "Birthday Boy," using 2D animation would have required more involvement from more people, and would have taken longer. "In 2D animation, you need to do cleanup, in-betweening [creating the drawings between key frames], ink and paint, layout, layout cleanup, and background painting," he explains. "With 3D animation, although the modeling and character setup take a lot of time, once it's done, there's no in-betweening or cleanup time needed." And, he adds, once a 3D character has been textured, it doesn't need to be textured again, as it would in traditional 2D animation.

Park began "Birthday Boy" by drawing the storyboard by hand. He then scanned in the storyboard, and used Adobe's After Effects to create a 2D animatic. To make Manuk, he first sketched him by hand, then modeled him in Alias's Maya. All the textures used for Manuk's skin and clothes were hand-painted. His clothing was scanned from an original concept painting, and his face was hand-painted in Adobe's Photoshop. Park created the airplanes, tanks, and trains in Maya, relying, he says, on a combination of period photos for reference and his imagination. "The models are not highly realistic," he notes, "but I tried to make them conceptually realistic for the story."

To achieve a consistent look for the project, Park had one associate create all the matte paintings for the backgrounds (in Photoshop and Corel's Painter) and another do all the lighting (in Maya). He also sought a "stylized, realistic" look that was different from that of most other 3D animations. To do so, he chose to work with people on the basis of their artistic abilities rather than their technical skills. Rendering was done in Maya, and all the elements were composited in Discreet's Flame.
The look of concentration on Manuk's face is designed to mirror that of a real six-year-old boy who was observed by the animator.

Manuk, as the central and almost sole character in the film, represented one of the biggest challenges for the director. Park wanted him to look realistic enough to match the setting of the story, but stylistic enough to look like animation. "It was very difficult to create both a stylistic and realistic character," he said. He ended up widening the face and body of the child to achieve that stylized effect. But he sought to create textures and facial expressions that were as realistic as possible.

To make Manuk look and act like a believable character, Park studied the facial features, expressions, and movements of a real six-year-old boy—his wife's nephew. He videotaped the boy, then viewed the tapes as a basis for the boy's movement. "This was more of a study—I did not rotoscope any of the material," he says, "but used it for ideas." Manuk is completely keyframe-animated, notes Park. When Manuk marches at the end of the movie, his arms and legs are out of synch because the real-life boy moved that way in the video, and Park decided to copy that motion. And when the character sniffs, then wipes his nose with his hand, he's mirroring the movements of an actual child as interpreted by Park.

His live model's facial expressions also served as inspiration. One of Park's achievements in this film is allowing us to see Manuk's world not exactly through his eyes, but as reflected in them. For much of "Birthday Boy," we are at eye level with Manuk. His face often fills the screen. We watch him register determination, surprise, satisfaction, and wonder—emotions that seem genuinely childlike. Whether he is scurrying between bombed-out houses or scavenging in airplane wreckage, he is happy and content in a world that would seem bleak and frightening to us.
CG animation provided a cost-effective way to create scenes of 1950s Korea, such as an old crash site in which a rusting airplane lies embedded in a building.

Of course, it is his birthday, though to Westerners, there is little beyond the title of the movie that would indicate this, except for a few subtle cues. Park explains that the badge Manuk wears says, "Happy Birthday" in Chinese characters, and that the dinner table that appears in the final scene of the film is set for a special birthday meal and is clearly recognizable as such to Korean viewers.

Park's engaging protagonist, muted style, and affecting story have appealed to juries since the fim was completed this year. Besides the SIGGRAPH award, "Birthday Boy" has won more than 10 prizes in Australia, and recently earned an Award of Distinc-tion at Prix Ars Electronica in Linz, Austria, as well as the Jean-Luc Xiberas award for a first short film at Annecy.

Park, who has now graduated with a master's degree in digital media from the Australian Film Television and Radio School, is continuing a career as an animator and illustrator. Of the poignant message at the heart of "Birthday Boy," he says, "I wanted to make a film that was different from the usual ones with a lot of comedy and happy endings. It's been really encouraging to me to find that 'Birthday Boy' has been self-explanatory to those who have seen it. People obviously understand what I'm trying to convey."

Jenny Donelan is a contributing editor for Computer Graphics World. She can be reached at