Computer Graphics World

November 2008 38 ■ ■ ■ ■ CG I buildings, and the camera continuously moved through them. " e animation was done, and there was no way we could change the layout, but the number of buildings was so large that none of our machines could render the scene," explains Clarenc. e team had to drastically reduce the polygon count; they did so by baking the high-defi nition models onto lower-defi ni- tion models—sometimes as much as 10 times lighter. is involved both normal and color maps so that no one would be able to tell the diff erence if the objects were far enough from the camera. However, that was the easy part. After- ward, the developers had to fi nd a way to switch from the low-def models to the high-def versions, and vice versa, both in Maya and in the studio's proprietary MGLR rendering software. is enabled the artists to arrange the layout for each shot and add details where necessary while keeping the "non-important" zones as light as possible. "If our developers had not succeeded in doing so, the last sequence would have looked simple and empty," says Clarenc. VFX and More According to Dessons, the crew used a sig- nifi cant amount of simulation throughout the movie. For instance, the team animated groups of bats and rabbits using a behavior- based system. In the few occasions where there was water, the artists used simple transparent and refractive shaders. Mac Guff also developed new tech- niques to calculate clouds, reducing the overall time. is proved invaluable for a "cloud sea" sequence—in which the fl ying village is riding the cloud sea and dragons are crossing back and forth—containing a number of camera moves and set inter- actions. Here, the crew redeveloped the old-school ray-marching technique from the raytracer to get a real volumetric eff ect, although it resulted in huge rendering times (about 20 hours a frame). is technique was also used for the dragon trails, enhanced with a 2D mo- tion-blur process. e raymarching technique also provided the opaque smoke throughout the fi lm. "We also needed a smoke that reacted pre- cisely with the e n v i r o n m e n t . e ray-marching is a sphere-based technique whereby you build your smoke with spheres, so we couldn't get that interaction," says Dessons. So, the group used a voxel-based technique for a volu- metric eff ect. Building on that technique, they generated a particle system that emit- ted voxels for a waterfall scene; this enabled the artists to control the water animation. A Small World e exciting and universal story line, the large personalities of the characters, and the stunning visuals make Dragon Hunt- ers a movie for everyone. " is fi lm is an example of why I am working in the ani- mation business," says Coldewey. "And it is a great example of how Europe works together. ink about it: e French and the Germans produce something in Eng- lish for the international market. How cool is that?" Technically, the fi lm utilizes the best techniques available, borrow- ing from US animation schools, French artwork, and Japanese image layouts and atmosphere. Will that be enough to sat- isfy US audiences? " at's diffi cult to say," says Colde wey. "To get a family feature to US theaters, you need to invest more than we had to make this movie. Yet, I think there is a big audience in the US asking for this type of story." Perhaps so. As Qwak points out, the movie is full of contrasts. e tone of the characters is cartoony, even though they're textured like real ones. "We like the contrast between the adventure/sus- pense, and the sad/funny scenes," he says. Em- phasizing this con- trast, Qwak describes Dragon Hunters as Tom and Jerry go to Sauron's place (in e Lord of the Rings). "Everything is blended, just as it is in real life," Qwak adds. ■ Karen Moltenbrey is chief editor of Computer Graphics World. The team used Mac Guff's Symbor to generate the characters' hair and the fur on their cos- tumes. For each actor, they had at least three hair systems of varying densities and thicknesses. November 2008 38 times lighter. is involved both normal and color maps so that no one would be able to tell the diff erence if the objects were far enough from the camera. However, that was the easy part. After- ward, the developers had to fi nd a way to switch from the low-def models to the high-def versions, and vice versa, both in Maya and in the studio's proprietary MGLR rendering software. is enabled the artists to arrange the layout for each shot and add details where necessary while keeping the "non-important" zones as light as possible. "If our developers had not succeeded in doing so, the last sequence would have looked simple and empty," says Clarenc. VFX and More According to Dessons, the crew used a sig- nifi cant amount of simulation throughout the movie. For instance, the team animated actions. Here, the crew redeveloped the old-school ray-marching technique from the raytracer to get a real volumetric eff ect, although it resulted in huge rendering times (about 20 hours a frame). is technique was also used for the dragon trails, enhanced with a 2D mo- tion-blur process. e raymarching technique also provided the opaque smoke throughout the fi lm. "We also needed a smoke that reacted pre- cisely with the e n v i r o n m e n t . e ray-marching is a sphere-based technique whereby you build your smoke with spheres, so we couldn't get that we had to make this movie. Yet, I think there is a big audience in the US asking for this type of story." Perhaps so. As Qwak points out, the movie is full of contrasts. e tone of the characters is cartoony, even though they're textured like real ones. "We like the contrast between the adventure/sus- pense, and the sad/funny scenes," he says. Em- phasizing this con- trast, Qwak describes Dragon Hunters Tom and Jerry go to Sauron's place (in Lord of the Rings "Everything is blended, just as it is in real life," Qwak adds. Karen Moltenbrey is chief editor of Karen Moltenbrey is chief editor of Karen Moltenbrey Graphics World.

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