Issue link: https://digital.copcomm.com/i/26447
n n n n CG Water A CG “Dawn Treader” moves closer to the climactic sea battle within a dangerous storm, a result of work by modelers, animators, and simulation artists at The Moving Picture Company (MPC). to put the camera anywhere. So, from my side of things, the biggest concern was how we would do all the water. We had just come off Clash of the Titans (see “For Gods’ Sake,” April 2010), and had ported [Scanline’s] Flowline to [Pixar’s] RenderMan.” With 200 shots during the sea battle to contend with, they needed to optimize and refine the Flowline pipeline. “Te caches out of Flowline are immense,” Hahn says. “Tere’s no way to do a show like Narnia without hitting these issues. It takes a Naiads Although comprising only approximately 16 shots in, basical- ly, two main sequences, the work done at The Mill was artisti- cally and technically difficult. CG water is always difficult, and building a creature made of water especially so. To create the shots, the studio relied on Autodesk’s Maya, Softimage, and Mudbox; Next Limit’s RealFlow and Real- Wave; Mental Images’ Mental Ray; and five people who spent six months doing R&D. Soon after the children enter Narnia, Lucy spots the Naiads from the boat as it rides on the back of a wave. “They’re a water creature that we based on a young girl,” says Sara Ben- nett, head of 2D, “half girl, half mermaid. We went down a few routes as we made her completely with water sims. At first, she looked messy and ugly, like a fountain.” They started with concept art from the production unit and with picture references, and then created a CG model, a mesh made in XSI and Maya that they rigged and animated in Maya. This gave the artists a body from which to emit par- ticles. “We blended from a solid mesh to particles,” says Nico Hernandez, head of 3D. “We animated a solid mesh and then used that animation to drive dynamics and fluids, and used internal noise to make her look more like a fluid.” Compositors received 14 passes, including a solid pass 38 January/February 2011 day to simulate, and we had a 36-hour turn- around from playblast to test render. We couldn’t afford too many iterations. We had to develop a language so that when we saw a playblast, we could make a few adjustments and that would be it.” Controlling the water often happened on a case-by-case basis. “It’s being clever with pa- rameters, it’s applying an expression to break up the water after a certain age, and it’s adjust- ing gravity,” Hahn says. “It’s a big tool set, and good effects artists are hard to find. We really benefited by rolling the Clash team onto the show. [Creating the water] wasn’t painless. But it was less pain than I had imagined.” To integrate the boat into the CG water, the simulation artists generated simple meshes in Flowline that they moved into Autodesk’s Maya. Because the meshes showed the wave surfaces, the layout team could place the boat on the wave and the animators could move it in rhythm with the waves. Te Maya anima- tion then moved back to the simulation team. “Because the Flowline and Maya water sur- faces matched, they could run sims and have water splash upon the boat,” Hahn says. “Te boat is actual geometry, a collision object.” Interacting with the boat—riding on it and fighting around it—are three CG characters: Reepicheep, the little mouse who starred in the previous film; Eustace, a dragon; and a sea serpent. “Our work mainly centered on the character work,” Valdez says. Of that work, the main character was the mouse Reepicheep, who starred in 500 of MPC’s 700 shots. Battle Stations MPC also created a sea serpent that appears during the climactic battle, which happens when characters come to the final island on that was reflective and a beauty pass in which the whole envi- ronment refracts through the model. When she leaps through the water, she creates splashes and trails. “We also have vari- ous passes to make her break up into the ocean surface, a liquid pass that moves through her body to break up that so- lidity, and on top of all the 3D, we used some 2D live-action elements of bubbles and splashes when she’s jumping in and out of the water,” Bennett says. In addition, the crew created the CG ocean, blending it into live-action water. “It’s been amazing,” Hernandez says of the project. “We’re not like a big company that works on one project and peo- ple are on a pipeline. Here, everyone works closely with one another.” –Barbara Robertson