Disney Goes Open Source with Ptex
Candela adds, "Also, when we open source something, we want it to be a successful project. And we define success by other people using it and contributing back to it. So Ptex went out [in January] and within a few days, there were lots of tiny contributions of getting it to build in different environments. Nothing major architecturally but there is already a community building up around it. And if you look at the open source that's around in the world, 97% of it is dead. Someone put it out there and nothing grew up around it. We don't want to do that. We want to put things out there that will have a life of their own and be beneficial and be used."
"Glago was interesting because it was a small crew that was interested in doing things differently in a much lighter weight way," explains Brent Burley, principal software engineer and creator of Ptex. "And there was somewhat of a rebellion against UV textures in general because of the weight that we had both in human labor and computer resources during rendering, and so the leadership on that show was going to change completely to projection painting, so it's a different UV less painting but it has its own limitations and overhead. But they didn't have a complete projection workflow set up; they were just figuring that out and they had painted some things already and Ptex worked so well that they tried it and switched everything over and used it from then on. And we had some discussions and some very preliminary support in our proprietary painting tool, but I didn't anything for a while and it wasn't until after the textures were all painted that I found out that they used it on everything [on Glago] and it was a complete success.
"I think there was some reluctance to use it on Bolt initially because they were already in full production by the time Glago had finished. And they weren't up to speed to the point where they were hitting all the I/O problems that we had on [Meet the Robinsons], but we convinced them to try it with a backup plan in case everything was crashing and things didn't work like we expected. But then artists started redoing their UVs and once they started to see the benefit -- we had a bug called Unitile that would do an automatic UV of the entire model as a single Ptex file -- everybody started using that. And, luckily, there were never any crashes or any artifacts."
Not surprisingly, Pixar was interested in Ptex as well and now it's available in RenderMan. "And before we released it open source, we pre-licensed it with other vendors and studios and it was presented as a Eurographics paper [in 2008]," Hendrickson adds. "So the formation of it started out as grass roots, but the popularity of it has grown. So a lot of studios are adopting it now or have plans to adopt it."
Candela explains that Ptex has given them the ability to "paint textures onto geometric surfaces easily and is also friendlier on all the systems that serve textures to render farms. It gives us quantum leaps forward in our I/O throughput for when we're rendering and how we serve up data."