Issue link: https://digital.copcomm.com/i/1151096
www.postmagazine.com 21 POST JULY/AUG 2019 summer movies reflecting off something else," says Cooley. "We realized we could render it if we did some cheats. Then we filled it with 10,000 unique items, and added dust and spiderwebs on top of that. And, it actually worked!" According to Moyer, the team built the space into a hierarchy of subsets, where roughly each booth was a separate set, and then those were all pieced together into areas, and those were used to build out the mall. "We could activate, deactivate, and cut out pieces, sometimes even down to the individual geometric primitive level of visibility," Moyer adds. To move the sequences through the pipeline more easily, the crew used USD (Universal Scene Description), which baked down all the set and prop information into a simple scene description so animators and lighters could work within these larger segments and not bog down their machines. "There are sometimes millions and even hun- dreds of millions of curves in a scene, and we had to smartly move all that geometry through the pipeline and into lighting without killing our lights or our renderer," says Moyer. To that end, an auto- matic pruning system was devised that was able to work with all the refraction and reflection, as well as, on the slip side, turn off light sources and hide some reflections as needed. Sometimes that task was done by hand, sometimes it was automated. In fact, the artists spent a lot of time with the RenderMan team, realizing that glass, lighting sources and practical illumination were going to be a big challenge. In addition, they used a machine-learning denoiser from Disney Research Studio in Zurich that automatically removes the noise from a partially resolved global illumination render. "The denoiser does such a beautiful job that we were actually able to cut our render times to almost half, with the same or better level of quality than we had in prior films," says Moyer. "It unlocked all these workflows for us that we hadn't been able to have before." The denoiser, which has not yet been released, was written in two versions: one for the GPU and one for the CPU. Pixar used the latter. Another level of difficulty in the antiques mall resulted from the large amount of dust and spi- derwebs. For the webs, the sets department used Woody has aged slightly, with tiny scratches on his face. Bo now has more practical clothing, but keeps her shepherd's hook. Forky, seen here with Woody, is a new character made from trash elements.