Virtual reality is the star of the show at GDC 2016, but Star Wars also gets top billing.

Everybody is talking about VR in San Francisco this week, and everybody who's talking about VR is also talking about Star Wars: Trials on Tatooine, a demo that brings the galaxy far, far away to VR goggles.

It comes to GDC courtesy of ILMxLAB, a division of LucasFilm's special effects juggernaut focused on creating experiences that transcend modern moviegoing. And the future of cinema, according to ILMxLAB, is an experience.

Star Wars isn't something that you watch, in other words. It's something you participate in.

THE PRICE OF PARTICIPATION

Star Wars: Trials on Tatooine is what happens when the bright and creative minds at LucasFilm create a state-of-the-art sandbox using their iconic property. It exists to show possibilities. It exists to foreshadow the future. Unlike most of the VR at GDC this year, though, it has a very high barrier to entry.

As thrilling as may be to see the Millennium Falcon land in front of you, to interact with R2-D2 and help Han Solo repair his ship, or to wield a lightsaber, Star Wars: Trials on Tatooine is not something for your home VR experience — at least not now. Behind what you can see are massive amounts of technology, computing power and technical wizardry that fit better in an amusement park than your living room.

This became clear Tuesday evening, when two employees at ILMxLAB and one from Skywalker Sound told the story of Star Wars: Trials on Tatooine's creation.

It was a fascinating, often technical talk. And though it spoke of the future of cinema, it felt right at home at the Game Developers Conference. According to ILM, creating Star Wars: Trials on Tatooine, where players strap on a VR headset and live inside a scene ion the planet where Luke Skywalker grew up, was closer to developing a video game than a movie. They wrote a script and they animated the virtual world, but unlike a movie, players get to interact with it. Interaction is the domain of games, not films, and ILM treated Star Wars: Trials on Tatooine as much like a game as a movie.

But if Star Wars: Trials on Tatooine was a video game, it'd be tough to imagine a consumer PC capable of playing it.

For example, the original version of the Tatooine set piece included 400 GB of textures created at 8K resolution. That level of artistic detail makes sense if you're trying to create a photorealistic virtual experience that effectively transports viewers onto a movie set. But even the beefiest modern hardware had trouble rendering the VR world at 90 fps.

The upshot: Even ILM's might couldn't make it work as well as it needed to, so its creators significantly down-sampled many of the assets. Artoo's model, for example, contains a mixture of textures at original and degraded resolutions in Star Wars: Trials on Tatooine.

Of course, hardware-based compromises are nothing new. They're as old as the gaming medium. But the processing power to render the VR world became undeniable when ILM got into the technical details about what, ideally, Star Wars: Trials on Tatooine could run on.

Though Star Wars: Trials on Tatooine can run on lesser configurations, a presenter showed a more ideal setup, which involves four state of the art GPUs coded to run in parallel. Each frame is so complex that they use three of the GPUs to render it. Then they pass that to the fourth GPU, which does a bit of final processing and passes the final product to the VR display. This process — render with the power of three, pass off, pass off — repeats in parallel 90 times a second to make it run in real time.

When running on lesser hardware, ILM cut some more digital corners, rendering some things at half resolution to determine the chrominance and luminance for the dual-sunned planet. There's even a way to run it with two GPUs in parallel, which each rendering a frame for your left and right eyes, respectively. Again, not exactly a consumer-friendly solution.

Those weren't the only technical hurdles that ILM had to crest, either. Perhaps the most interesting tidbit of information had to do with the lightsaber that Star Wars: Trials on Tatooine players eventually pick up. The VR experience runs at 90fps, much higher than the 30 or 60fps of non-VR games — and significantly higher than the 24fps standard of movies like Star Wars. Wielding a lightsaber at 90fps doesn't look the same as watching a lightsaber at 24fps. It's not a one-to-one comparison, and the developers spent a lot of time figuring out how to recreate just the right amount of motion blur in 90fps to recreate the look of 24fps as players swing their laser swords through the air.

AN EXPENSIVE PRESENT FOR AN INEXPENSIVE FUTURE

A few years ago, 3D TVs took the annual Consumer Electronics Show by storm, as manufacturers pushed what they believed would be the next big thing in home entertainment. Something similar is happening this year at GDC. Virtual reality, which was a theory for decades, is on the verge of becoming a consumer reality.

Many of the biggest stories at GDC 2016 are about virtual reality. And almost all of them are about the VR that could be in your home by the end of 2016.

Star Wars: Trials on Tatooine is not one of these things. It is a leap beyond, generations beyond what you might experience in the comfort of your own home. It is a deeply impressive technological achievement, but its practical implications in 2016 are, based on what I've seen, years away from consumer grade practicality.

There's nothing wrong with that, of course. ILM is pushing the technological envelope. I'd be shocked if the technology they're inventing didn't wind up in your home one day — but not today or tomorrow or this year or next.

It also fits into the narrative that virtual reality proponents have espoused during the last few years. VR may begin with video games and its early adopter crowd, but few believe it will end there. Facebook didn't buy Oculus because it wanted to get into gaming, after all. It bought it because it believes that VR has applications well beyond that ecosystem.

As deeply impressive as Star Wars: Trials on Tatooine is, it's more of a harbinger of things to come than an practical experience. In 2016, it's not the stuff of home entertainment. LucasFilm isn't pretending it is. Instead, it's the kind of experience you'll need to spend 90 minutes in line to see at an amusement park.