When Pixar president and co-founder Ed Catmull announced his retirement earlier this year, people rightly saw his impending departure as a transitional moment for the animation studio. But it's bigger than that. Catmull's shadow looms large not just over groundbreaking films like Toy Story and Coco, his influence can be traced all the way back to the dawn of digital visual effects. Star Trek II: The Wrath of Khan. The Abyss. Terminator 2. Jurassic Park. All of these titles came out before Woody and Buzz Lightyear, yet all remain watershed moments for VFX—and all used the tool that Catmull and his colleagues helped create at George Lucas' Industrial Light & Magic.

RenderMan, as it's known, came out of ILM's computer graphics team (the same one that would later spin off into its own company called Pixar). It started as a powerful algorithm, but then became something greater—a graphical interface. "Up until that point," says Catmull, "the look, the lighting, essentially had to be done by programmers." A movie like 1982's Tron might have been mindblowing, but its digital sequences also necessitated an absolutely knee-buckling amount of work, creating its futuristic effects frame by frame. RenderMan, though, allowed effects artists to realize their visions without needing to write code.

That's not to say that the software was simply a visual front-end. The team behind RenderMan also helped pioneer everything from motion blur to path tracing to subsurface scattering—effects that added so much incredible realism it's hard to imagine today's movies without them. And when Pixar ventured into making features, RenderMan proved to be as central to the studio's animation efforts as it was to Hollywood's most innovative live-action films. Since inception, the program's powers have grown—what used to take all night on a render farm for Toy Story can now be accomplished in real time—but Pixar filmmakers like Coco's Lee Unkrich are still using it to push the limits of visual storytelling, without sacrificing emotional payoff.

In the 30 years since RenderMan became available, 27 of the 30 films to win the Academy Award for Best Visual Effects used it. And judging from just some of the 2018 movies it helped create—Avengers: Infinity War, Black Panther, Ready Player One, A Wrinkle in Time, and Robert Zemeckis' Welcome to Marwen—odds are good that it'll soon be 28 of 31. That's just scratching the surface, though; we visited Pixar and dug deep into the archives to put together an exhaustive video history of the software that powered the VFX revolution.

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