No Man's Sky is so big, the developers built space probes to explore it for them

There's a robot that lives inside No Man's Sky that nobody outside of the development team may ever see, because its entire purpose is to fly to each of the game's 18 quintillion worlds, take short videos and document its interstellar travels as a series of animated GIFs.

Developer Hello Games built this probe because, at its core, No Man's Sky is so massive that its statistically insignificant team of four human artists can't control or oversee its creation. At best, they can audit some of what already happened and adjust accordingly.

So, instead of pure human oversight, No Man's Sky is governed by what art director Grant Duncan calls a team of thousands of "mindless idiots" — the computer code and algorithms that take the structure that he and his team created and turned that into a universe.

The decision to give up control wasn't easy. Duncan's now-loving embrace of procedurally generated art started as something that existed on the continuum between ambivalence and outright hostility.

But now, deep into the development of No Man's Sky, and despite his initial reservations, he learned to stop worrying and love procedural art, a process he documented in a GDC 2015 session this week.

The problem that probe is designed to solve is one that hits artists particularly hard: When every atom is procedural, developers must, by definition, lose control. Duncan learned to embrace this, at least in part out of the necessity to create a universe with planets numbering in the quintillions (a number so big that he admits to it being "entirely meaningless" to the human mind). Thus, the autonomous robot and the "idiotic" team of virtual art directors that keep tabs on the unfathomable number of celestial bodies, their flora, their fauna, their geography and their indigenous creatures.

The idiotic robots Duncan deployed are responsible for creating what players will see in No Man's Sky. This is no exaggeration. There was no other way to create the the open universe game set for release sometime this year on PlayStation 4 — and, presumably, later on other unspecified platforms.

It really is a universe, full of a myriad of stars. Each star has a solar system. And each solar system has planets. And planet-hopping — the process of traveling from planet to planet, solar system to solar system and galaxy to galaxy to explore and exploit — is perhaps the easiest gameplay mechanic to understand in No Man's Sky, a game whose whose other activities Hello Games has been deliberately tight-lipped.

Near the beginning, while creating the vast universe of No Man's Sky, Hello Games began with the idea of with planet-hopping. And when making something like that an intrinsic part of the game, they needed to do more than just create planets. They needed to fill them with plants and animals that made them feel alive.

To invent these alien worlds, the developers took inspiration first and foremost from something that might seem surprising: not games, not movies, not sci-fi novel covers, but the real world. Hello Games wanted No Man's Sky to be grounded in the "believability" of the real world, Duncan said, which is already filled with "bonkers" and "crazy" things, whether animal, vegetable or mineral. And if they wanted players to explore their creation (and they do), they had to make their universe and everything in it interesting and strangely familiar.

It may be a surprising twist, but it's not without logic. Just think of how many exotic and varied species of frogs exist in the real world, from the standard, green croaking lumps of fairy tales to the little neon-colored poisonous monsters of the rainforests. In No Man's Sky, reality established the rules. Then the artists went about breaking them to create alien creatures, planets and geographical formations that are, fundamentally, grounded in reality.

To populate this alternate reality, the artists created seeds: the essential parts of plants and animals and geographic locations. Trees have trunks and leaves. Animals have bone structures. Spaceships have cockpits. Buildings have doors, windows and roofs.

Then they threw those seeds into what Duncan calls a "big box of maths," where the British developer's algorithms create variations on those themes. Short trees with orange foliage. Spaceships with stubby cockpits. Alien creatures whose deer-like ancestry is graspable at a glance.

Feed No Man's Sky's big box of maths the same inputs — the art team's seeds — and it will produce the same outputs, whether on your system or a friend's. That's where its mighty universe comes from.

But that's the technical side of the equation. Duncan is an artist. It's his job to ensure that what the math box creates makes sense, looks pleasing and, though alien, feels familiar. And that happens at the intersection of art and math, a crossroad that makes some artists uncomfortable.

When he started working on procedural generation and No Man's Sky, he contacted several artist friends, many of whom shared the approximate opinion that, as Duncan put it, "procedural is a big pile of shit." It creates terrain so realistic that it's boring, they said. It creates blobby, cartoony creatures, they said. It takes control way from artists, they said. It's "programmer art," which isn't really art, they said.

Procedurally generated art requires the artists to surrender control

Moreover, if the Hello Games art team was just recreating things they found in the real world, that'd be boring. It's uninteresting to artists, who see procedural technology as random and, he said, "can never lead to good art or that produces "inferior visuals."

Duncan's job was, in a sense, to prove the doubters wrong by convincing them to let go.

"I think that the truth is, we're actually all control freaks," Duncan said. "Artists are so used to having complete control of every single pixel. Especially now with digital artists. We can get Photoshop, we can zoom right in and obsess over something no one will ever care about."

So the artists at Hello Games created a blueprint system, wherein the artist creates a template. It begins, in other words, with handmade art. Then the math box creates variations on those themes — it tweaks the lioness' leg length, stretches her neck, colors her.

The tiny team focused on efficiency, again out of necessity. To create as little work as possible, they identified similar things, like bone structures. The system can move bones around and create poses that range from owls to proud stallions and "hundreds" of different movement cycles. That applies to everything from ships to sea creatures. In No Man's Sky, dolphins, sharks and whales all share a common ancestor.

But Duncan's artist friends were right about at least one thing: feeling the box of math isn't enough. That process is mechanical, and math doesn't have the same artistic sensibilities that humans do. So the artists collaborated with the coders to make random generation more pleasing.

Now the box of math nows that, when it places a boulder on the ground, it should also place a few medium and smaller boulders around it. It makes sense. You get, he said, "a lot more pleasing silhouettes."

If you're going to create a universe for people to explore, you've got to make it believable.

That same system of symmetry applies to entire planets. One gets created, and it has certain properties. Those properties (say, a blue mineral) have an effect on the plants that grow on the planet and the creates that inhabit it, informing everything from their design to their complimentary colors. But before Hello Games' artists did that, they had to teach art to robots.

Finally, after the artists created the blueprints and planted the seeds, and after the coders constructed a box full of math, the universe exists. Someone has to look after it.

That's where the robot probe comes in, flying from planet to planet, making the animated GIFs, so that the folks at Hello Games can make sure everything looks acceptable. That there aren't too many red planets; if so, they can fly in and tweak things to ensure consistency and coherency.

Because if you're going to create a universe for people to explore, Duncan said, you've got to make it believable for players. And that, beyond just designing things, is the job of an artist.

"The best games to me" Duncan said, are those in which "you don't question anything. Things just feel like they belong together."