Witches Brew
Issue: Volume: 26 Issue: 10 (Oct 2003)

Witches Brew

By Karen Moltenbrey

Cinderella had her fairy godmother to watch over her, but in this all-3D television special from Mainframe Entertainment, a frightened little girl finds comfort in the hands of her scary godmother, who shows the youngster the sensitive sides of her ghoulish pals. Creating this unusual tale required Mainframe to update its graphics pipeline with tools that would enable the artists to achieve the project's complex effects.
Images © 2003 Scary Godmother Productions, Inc. Courtesy Mainframe Entertainment, Inc.

On a scary, scary night one recent Halloween, a spirited little girl named Hannah Marie is tricked into visiting a spooky old house by Jimmy, her nasty older cousin, who wants to free himself of the pint-size tagalong so he can continue trick-or-treating with his friends. Alone inside the creepy structure, the frightened tutu-clad youngster begins to cry, when who should appear, but her scary godmother. When the child confesses her fear of monsters and things that go bump in the night, the friendly, bewitching witch had a plan. She will take little Hannah to her house on the "fright side" for a Halloween bash, so the girl can meet her "broom mates" and ghastly guests. Later, having conquered her fear, Hannah returns to the spook house with her new fiendish friends, and together they have a frightfully good time scaring Jimmy.

This spooky tale, which puts a ghoulish spin on the classic fairy godmother story, serves as the plot for a one-hour television special airing this Halloween season in Canada, Europe, and Latin America, and next year in the US. Fittingly titled Scary Godmother, the show is based on the illustrative comic book and children's book series by Jill Thompson, who, along with Heath Corson, also wrote the television script. A few years ago, animation studio Mainframe Entertainment (Vancouver, BC) acquired the rights to Scary Godmother, and recently decided to bring the unusual cast of characters to 3D life for the TV special, using the project as a test bed for its new Softimage|XSI pipeline.

"The unique look of Scary Godmother required us to examine new production tools, so it seemed like the perfect time to move from Softimage|3D to XSI," says David Fracchia, vice president of technology at Mainframe. "Also, because we owned the property and decided to market it as a finished project, we had more flexibility in our schedule and more resources available for the project, enabling us to really test the software to see what it could do."

"We used 12 iterations of the software before we were done: XSI 2.03, 3.01, and everything in between," notes Mike Monks, model supervisor. Adds director Zeke Norton: "Sometimes, after [software technical lead Gordon Farrell] had installed a new version, the crew would begin working, only to find that a certain button didn't function the same as it did the previous day." Despite these expected snags, the transition was relatively smooth, according to Fracchia, allowing the group to concentrate at the other task at hand—completing its scary tale. Spooking in Style Aside from Scary Godmother's story line, another aspect that sets the production apart from most long-form animation projects is its stylized look—a "concoction," if you will, of different techniques. Overall, the imagery more closely resembles that of The Nightmare Before Christmas rather than that used in recent CG films such as Finding Nemo and Monsters, Inc. Moreover, several elements in Scary Godmother, such as the characters' hair and fur, are distinctive and undoubtedly 3D. They're also a far cry from Mainframe's initial vision of a 2D-like cartoon-shaded style, which is similar to the one the studio uses for Sony Pictures Television's new Spider-Man series, now airing on the MTV network.

"We thought we'd try to capture the style of Jill's artwork by creating something that resembled an animated 2D watercolor painting," says Norton. "But when she saw [our concepts], she said, 'No, no. I want it to be a 3D version of what I am doing.'" As it turns out, the final look is actually a mixture of the two animation styles—the backgrounds, for the most part, are static with a hand-drawn cell appearance, while the elongated CG characters show their dimensionality by "popping" into the foregrounds. Even the characters have diverse appearances—from the wide-eyed, anime look of Hannah to the simplistic style used for Jimmy and his friends to the softer, more sophisticated appearance of the creatures.

Artists used Softimage|XSI's fur simulator to texture the hair-raising creature Bugaboo.

To create the majority of the background imagery, the artists used Softimage|XSI for the geometry, and Adobe Systems' Photoshop and the freely distributed GIMP (GNU Image Manipulation Program) for hand-painting and manipulating the textures. As art director for the program, Thompson also provided selections of her artwork, which were used as matte-painted backdrops or as textures for the 3D sets. To enhance the watercolor look and to mimic Thompson's style, the artists generated a thick, black cartoon edging around the background objects and the 3D background geometry using XSI's Toon Shader. "As a result, our computer-generated set looked like Jill had painted it," says Norton.

For two unusual scenes—a monster-mash dance segment and a "treats" sequence, in which Scary Godmother conjures up one of her special recipes—the action unfolds on 2D animated abstract backdrops created with Adobe's After Effects. "These were little scenes that truly reflect Thompson's artistic style," says Norton.

The animation effects used in the production vary widely, from the realistic billowy clouds (top) to the cartoonish hard-edged backgrounds (bottom).

Providing a contrast to the production's cell-like backgrounds are the billowy clouds through which the witch and Hannah fly on their way to the fright side. The clouds, one of the more challenging aspects of the project, were created in XSI as composited effects within the software's FX Tree. Because the FX Tree is integrated into the compositor, the artists—rather than postproduction editors—produced the effects. Moreover, they were able to view the cloud results quickly and make changes on the fly, thereby speeding up the process and allowing more time to work on the effect.

To create these puffy and wispy clouds, the artists built rough geometric models using simple distorted sheets and balls, and then added animated displacement maps atop the models. "This resulted in basic, straight-forward geometry," Corey Barnard, supervising animator, states. The group then "fluffed" the shapes by adding a long list of effects—such as various turbulent distortions, swirls, and blurs—within the FX Tree compositor to achieve the final look. In fact, Softimage highlighted Mainframe's use of the FX Tree for this effect during one of the vendor's advanced technical sessions held at the SIGGRAPH conference and exposition this past July.

Unlike the overall hand-painted look of the backgrounds, the characters have a three-dimensional appearance and are not 'toon-edged, even though both were created using the same tool set. All the characters were generated using polygonal modeling and subdivision surfaces, resulting in fairly comprehensive models. Even so, some of the characters—namely, cousin Jimmy and his friends—have a more simplistic composition compared to the more stylized Scary Godmother and most of her broom mates, who have hair or fur. "Creating the hair was the most difficult part of the project, even more so than generating the clouds," Monks contends. "Because of our [self-imposed] deadline and budget, we couldn't add too many fancy things into every shot. Throwing hair into the show was about as far as we really wanted to push things while trying to establish a new pipeline."

The model phases of Harry, the werewolf, are shown in this series (from top to bottom): polygonal mesh with skeleton, subdivided high-res mesh, shaded surface render, hair growth guides, and fully rendered image. Pictured below is a final frame from the

In fact, two of the characters were completely covered in fur—Harry, the highfalutin werewolf, and Bugaboo, a large rotund creature with several bulging eyes. In addition, Scary Godmother's skirt and hair, as well as Hannah's tutu, have an unusual texture that was created using the same hair technique. In the past, the team would have used its own hair/fur shader, which had been written by Fracchia and the software team, to accomplish these effects. However, since converting from Softimage|3D to XSI, Mainframe's shader was no longer compatible. With no time to rewrite the tool, the artists instead generated these surfaces using the hair and fur simulation system built into XSI. "It worked great, so now we can consider integrating the [hair and fur] feature into our future productions," adds Farrell.

Creating the hair and fur was challenging enough, yet complicating the task was the characters' complex and extreme motions. For example, Bugaboo's emotions are portrayed through a multitude of over-emphasized expressions and poses achieved through forward and inverse kinematics. "Bugaboo essentially is one great big mouth and a bunch of eyeballs, and when he opens and closes his mouth, his face almost folds inside itself," explains Monks. "This meant that his geometry had to be flexible enough to handle his exaggerated movements."

Scary Godmother is far more bewitching than Hannah, thanks to the effects achieved with XSI's hair/fur simulation tool.

To save time while creating the animation, the team initially worked with a hairless model. After getting approval for the animation, the team textured the beast—and received some unexpected results. "When we finally added the fur, the extreme poses often made the hair do interesting things that we didn't want it to do, such as sticking straight up or even protruding through the character's mouth," recalls Norton. After what Norton refers to as a brief moment of panic, Barnard used animated masks within the FX Tree to correct, or hide, those problems. "We were able to make the adjustments within the compositing stage, so we didn't have to fiddle around with the hair settings or change the animation that had already been approved," he says.

Whereas many action-oriented animations contain short shots (4 to 5 seconds) and numerous cuts, Scary Godmother's shots are significantly longer—15 to 45 seconds, with multiple characters passing through a scene. "A community theater group in Chicago put on a play, adapted from Thompson's first book, which was the basis of our project," explains Norton. "And what seemed to drive the narrative of the show were the dialog, jokes, and conversational gags. So, we decided to implement those features whenever possible in our production."

Although creating longer shots enhanced the storytelling qualities of the tale, this approach made the animation process more difficult, especially since all the motion was keyframed. To keep the characters "alive" during these long shots, the animators used XSI's Animation Mixer, enabling them to blend their keyframes and extend their animations. "There are times when, as a director, you change your mind about something after an animator has gone a long way down a particular path," says Norton. "In those instances, we were able to reuse a lot of the work by modifying it within the Animation Mixer."

The team found this animation blending tool especially useful in two particular sequences. One is the entire dance segment, in which Hannah and the monsters boogie to a catchy beat. The other is a chase scene, in which a frightened Hannah, having just met Harry, runs through Scary Godmother's house, with the monsters in pursuit. In these segments, the animators blended specific character movements in and out of the dance and run cycles. "We could quickly throw the characters together in a scene with general [animation] cycles, choose the spots where specific keyframed animation was needed, and then use the Animation Mixer to smoothly blend in the [new] movement," explains Norton.

The blend feature also worked well with the company's proprietary lip-sync system, called Grimace. Previously, Mainframe artists used Grin, a lip-synchronization tool the studio developed to work with Softimage|3D. "We weren't at the point of developing the XSI pipeline where we could easily write tools to import models to and from Grin," notes Fracchia. "So our software developers and TDs developed Grimace, which mimics the functionality of Grin but within the XSI environment." Moreover, by using Grimace in conjunction with the Animation Mixer, the artists were able to re-purpose certain facial animations, thus simplifying that task.

After the team completed the modeling and animation, it composited the imagery using both the FX Tree and an in-house system, at times compiling upward of 30 layers of effects, backdrops, models, and objects. Rendering was accomplished using Mental Ray from Mental Images. In addition, the group re-vamped its proprietary asset management system to work with XSI. The tool contains a shot-tracking setup, enabling the group to archive scenes as well as retrieve, modify, and edit images as needed. The management systems, as well as all the content-creation tools, run on Linux-based Hewlett-Packard and Dell workstations.

The team repurposed certain motions for the characters, including the king and queen of the night, using the Animation Mixer.

In spite of the trial-and-error work flow dictated by the converted pipeline, the group was able to complete Scary Godmother in approximately eight months. "Regardless of the learning curve, the production looks amazing," enthuses Norton. "Creatively, I think it is some of our best work." The team is now using its newly installed software base for preproduction of another one-hour prime-time television special that hasn't been announced yet. "The work that the crew did for Scary really paved the way for other projects," adds Fracchia. "Now we have the sophisticated tools that will enable us to develop projects, such as this, which we could never have considered earlier."

Whoever said that creating an entirely new pipeline while in the midst of production would be "scary" wasn't telling a fairy tale.

Karen Moltenbrey is a senior technical editor at Computer Graphics World.


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