Computer Graphics World

CGI n n n n The branching structure was complex and it had too many thorns. We had made complex buildings, but this silly plant killed us. We learned our lesson and fixed it." One of the big action scenes in the movie takes place in the desert as two carriages race through a desert canyon. "We had a lot of trailing dust next to cliff edges and spew- ing rocks," Bielenberg says. The effects art- ists sent rocks off the cliff using a mixture of Autodesk's Maya and Side Effects Software's Houdini. "During the course of Puss in Boots, we used Houdini so much that we ended up working out a site license with Side Effects," Bielenberg says. "It's definitely part of our core set of tools." A Growing Concern The largest environment, though, and the largest effects sequence happens when Puss, Humpty, and Kitty plant the magic beans. A giant tornado created with particle and fluid simulations drops down from the sky and drills into the ground. There, a beanstalk explodes from the ground like a rocket and climbs up into the clouds (see "Creating Cloud World," pg. 14). To grow the beanstalk, the effects, model- ing, and layout departments had to break from the typical workflow by which models move through the pipeline. "We grew the beanstalk procedurally, so we had UV issues, texture stretching issues, and we needed to do more procedural textures," Bielenberg says. "And, we couldn't give rough models to layout. We grew the beanstalk and handed it to layout. They blocked in a camera. We made the beanstalk look better. They adjusted the camera. It was an iterative loop; not our normal path. But by participating in the camera process, we could help work out the best way to utilize the ste- reo aspect. We're always looking for story- driven stereo moments for our films, and the beanstalk was one of those sequences." Puss, Humpty, and Kitty climb the plant up through the clouds to a giant's castle, and inside the castle, the characters find themselves in a jungle, and then in a moat. Both sequenc- es landed in effects late in the process. "Sud- denly, we had to create our version of an Ava- tar moment with a complex and giant jungle, and then we had a water sequence," Bielenberg says. "We used our ocean height-field system to generate waves for the water, particle simu- lations to create individual splashes, and fluid simulations for foam." During the sequences, the characters find themselves swirling in a whirlpool within the moat. The challenge for the effects and anima- At top, Jack and Jill are the two main human characters, but Puss's home town has many more, all created with "half-hero" facial rigs. At bottom, now that he's a hero, Puss has more hair than before, and the fur responds better to his movement. tion artists was to match speeds for the two el- ements—characters and water. "We did some initial simulations and put in some red spheres for markers to show the intended speed of the flow, and sent that to animation," Bielenberg says. "Invariably, though, the animators want- ed the characters to go slower or faster than the water, so we iterated until we got that right. Maintaining the right sense of drama and ur- gency with the speed of the characters and the water was very important. The whirlpool, the dust, the jungle, and the clouds were our big- gest effects challenges." Among them, the clouds were the most difficult. "Creating the cloud world was an extraordinary challenge," says Brett Miller, effects lead. "They have incredible depth and texture. You can enjoy them in 2D, but they're really great in 3D. The clouds were something that executive producer Guillermo del Toro re- ally pushed us on. He saw that the cloud world was surreal, and he said, 'If you are going to do it, go all the way. Push the envelope.'" Chris Miller pitched the film to del Toro, who had directed the award-winning, live-ac- tion feature Pan's Labyrinth, during del Toro's visit to DreamWorks early in production. "He came to a screening and loved the movie," Miller notes. "He said he wanted to be part of it, and by the next afternoon, he was the executive producer. He would come in once a month and we would show him everything. He had great insight into all aspects of the film." Often, DreamWorks' animated features have two directors, so for Miller, who was the sole director on Puss, having del Toro available was especially exciting. "It was great to have a guardian angel to talk to who could champion the film," Miller says. "By the time the third Shrek had come around, that world was settled into its ways, so this film felt like my first one. It was liberating." Once upon a time, as the making of Puss in Boots' story goes, there was a simple movie, a spin-off that people could easily dismiss. But it grew and it grew, and became a bold, colorful, complex film. "We took our lead from Puss," Miller says. "Everything is a reflection of who he is." n Barbara Robertson is an award-winning writer and a contributing editor for be reached at BarbaraRR@comcast.net. October/November 2011 17 . She can Computer Graphics W orld

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