Why developers love HDR more than anything else in the PS4 Pro

Fluffy clouds.

Standing in the darkened backstage area turned PS4 Pro arcade of the PlayStation Theater earlier this week, I quietly watched Shuhei Yoshida listen to a Naughty Dog developer talk excitedly about a television screen half-filled with powdery white clouds.

The pure tumult of the setting, soaked with the bass of video game gunfire and explosions and white noise chatter of journalists, developers and executives, made it impossible to hear what was being said.

But Yoshida, head of PlayStation’s worldwide studios, seemed enthralled.

Christian Gyrling, lead programmer at Naughty Dog, shifted back and forth between where Yoshida sat and the television, often pointing to the clouds.

Beneath that virtual blue sky freckled with clouds stood an obviously bored Nathan Drake, shifting uncomfortably in the sand of Uncharted 4 as he waited for someone, anyone, to do something that involved more shooting and less cloud discussion.

The chat wrapped up, and Yoshida made his way to another game after a friendly wave.

It was my turn to talk clouds.

HDR

With all of the discussion of 4K resolution, quadrupled graphics power and tweaked CPUs, the thing that seemed to most entrance the game developers gathered in New York City for Sony’s official unveiling of the PS4 Pro wasn’t smoother frame rates or more pixels. Every developer I talked to seemed ecstatic at the idea that they would be able to finally show gamers the nuance of colors and spread of light and shadows their games have always really had, but could never use.

High dynamic range color, which is coming to both the PS4 and PS4 Pro if you have a TV that supports it, essentially gives a television the ability to show a broader range of contrast. So whites can look whiter and blacks, blacker. More importantly, a TV show, movie or game can display a much more nuanced range of whites and blacks and most colors to bring more life to an image.

And it turns out that clouds are a great way to explain how that works.

After chatting with Gyrling for a bit about how the Pro wouldn’t be able to deliver a frame rate advantage over the standard PS4 in online games, I asked him which was a bigger deal: HDR or 4K resolution.

"Personally," he said, "it’s HDR all the way.

"Once you’ve been looking at it for a while, in your mind, other images that you’ve been looking at all along look muted. When we look at the clouds, the thing we see here, when the sun hits the clouds, it really shines bright, but because TVs can’t show that brightness unless they are in HDR, it’s lost.

"Let’s look at this cloud here, for example."

Naughty Dog/Sony Interactive Entertainment

And then we were examining and discussing the clouds languidly floating over Drake’s head.

What happens when you’re not using HDR is that all of the nuance found in a cloud is essentially flattened. Where real clouds show patches of varying degrees of white and gray, a video game cloud will sort of normalize those colors and create something that, by comparison, looks washed out.

If you haven’t looked at a cloud on an HDR television, you likely wouldn’t notice this. But when Gyrling flips between non-HDR and HDR on the same screen, the difference is glaring. Or perhaps I should say it’s plain. And it’s not really about the colors as much as it is about the brightness, or the contrast, that a television can deliver.

Jason Connell, art tech lead at Sucker Punch Productions, seems almost offended when I ask him if the team is considering adding the option to turn HDR off once Infamous: Second Son and Infamous: First Light are patched to include the technology.

The team has discussed it, he said, but absolutely no one who has seen HDR in the game doesn’t like it.

"HDR is pretty big," he said. "I worked on the lighting and I’m very, very sensitive to it. This is a game about superheroes with neon lights, wet streets and reflections.

"I’m shooting laser bullets out of my hands. Why wouldn’t I want HDR?"

Later, I watch as someone plays around a bit with Abigail Walker, the lead in Infamous: First Light, who can absorb neon lighting and then shoot it out at enemies, among other things. Her blasts of power are almost physical when they light up the screen, the contrast is so stark. I feel it almost as much as I see it.

For a second, I think there’s something wrong with the game when the developer turns off the HDR to show the difference. It looks almost too dark to play by comparison.

Graham Aldridge, lead graphics programmer at Sony’s Bend Studio, said that upcoming survival horror game Days Gone is a perfect fit for HDR.

"We’re very happy for you guys to take a look at this," he said in a roundtable interview. "We think it looks absolutely fantastic. The details are dramatic."

Because the game has day and night cycles, and because it has players going into darkened buildings and then out into sunny days, HDR helps represent the game’s extreme range of lighting, Aldridge said.

"It means we can properly represent those brightnesses," he said. "It’s quite amazing."

It’s already there

All of the developers I spoke to also noted just how easy it was to add HDR to their games. Aldridge said adding it had an extremely small impact on development.

It turns out that a lot of these games already had the assets in place to support HDR.

Connell said that both Second Son and First Light were built with an "almost full HDR pipeline."

"The work was already done ahead of time," he said. "The resolution was a little bit of work that hadn’t been done yet."

Gyrling said that adding HDR allows developers to show gamers the colors that they’ve always intended to show.

"These colors existed all along in the game; we haven’t changed anything," he said. "We’re just saying, ‘Oh my god, you have a TV that allows us to show you what we intended. Here you go.’"

He said that "99 percent" of the game is the same.

"All the way from the original source asset, all the way through the engine, the rendering," he said.

A few years ago, he said, a lot of people were talking about HDR lighting, which was internal to some game engines.

Sucker Punch Productions/Sony Interactive Entertainment

"We would light the scenes with our dynamic lights, to look like this," he said, pointing to the television. "We allow things to be really, really bright, but at the tail end we need to change to support whatever TV and the format of whatever TV you have.

"So we’re pulling it back down, bringing it back down to a very narrow space, because that’s the kind of TV you have. And now we’re just opening up the box."

For Uncharted 4, he said, all the team did was change the code, not the whole game — just the last part of it to allow for HDR.

"We’re going to what we call ‘deep color’ using a little more precision, getting more different colors in the darks, blacks, also the lights," he said. "We’re talking changes in really, really bright values. You can see it, your pupils are dilating, to the point that you can see that is different, but that is completely gone when we switch back to non-HDR."

And then he turns back to the clouds to point out the peaks of brightness and specks of deep gray woven into them.

"What happens is, all of these colors, these colors — these brightnesses, really — they’re not able to be represented by normal TVs, so they [are] painted down. They might look like nice fluffy clouds, but [HDR] is what you would see if you went outside and looked at the sky."