Naughty Dog has already said that The Last of Us Remastered, the PlayStation 4 update of Sony's much-acclaimed survival horror game, will run at 1080p, and the team is aiming to keep it locked in at 60fps. But what's different about this version of the game? After a short play session with a recent build of the game, it's no surprise that it looks better. The colors feel more vibrant, and in those rare moments when you step out into the sun, the horizon seems to stretch forever.

But if The Last of Us already looked great on PS3; so why does it need another version that doesn't add new content? One of Sony's reasons is that a large proportion of PS4 owners haven't played The Last of Us on PS3, but I recently talked with Naughty Dog's Jason Gregory (lead programmer), Christian Gyrling (lead programmer), and Ricky Cambier (lead designer) about why exactly they want to revisit last year's game.

Why is 60fps important?

"It was a toss-up before; people were saying that you lose quality and graphics and what not," Gregory said when asked why Naughty Dog feels that it's such an important component for the game. "But being able to compare apples to apples like we have now with The Last of Us, going back and playing the 30 Hz version feels, to quote some people in the office, 'broken.' There's something that can't be captured in screenshots and playing an adventure game where you just walk around and experience the world at the smooth 60 Hz. [Editor's note: throughout the interview, the Naughty Dog team used fps and hertz interchangeably] You really just have to feel it."

"There was an internal debate just over the artistic-ness of going 30 or 60, and whether or not it would feel weird. Pretty much every person who had said, 'I'm a 30 Hz person, I don't know if I could play it at 60.' When they finally saw it, they said, 'Nevermind, I'm convinced.' We do so much with the animations of the character to convey emotion to the player so when you talk about what's going on with Joel and getting the player to empathize with him. At 60 frames, seeing his breathing change, or when a Clicker shows up and you hear that sound and the way he moves changes, because all the animations are that much more fluid, I think that comes across even more now. That's going to change the play experience just a little bit in the way the players experience that."

You'll be able to see the difference yourself soon enough. In addition to the stream of comparison videos we'll be putting together, Naughty Dog director Neil Druckmann mentioned on Twitter, "Since some people asked for it, we added an optional 30fps mode (gameplay & cinematics). My pref is 60fps all the way."

Will 60fps become the new standard in games?

"We hope so," Gregory said. "It used to just be that first-person shooters were 60 by default, but a lot of other games didn't feel the need for it. I think we're showing that it does make a difference even in a non-FPS type game. And one question that's been fielded on Twitter as a follow-up to the 60 Hz, is whether or not we're always at 1080p. Some games have been doing the whole adaptive resolution where they change the resolution based on what's going on. We are always at 1080p."

What exactly has changed for this version of the game?

"We up-resed textures, we also turned on various graphics features that, on the PS3 we could only afford to turn on here and there in certain spots where it really offered bang for the buck, and in some cases those are turned on across the board now, like the bounce light from the flashlight," Gregory said. "There's better anti-aliasing. Just a host of graphical improvements that bring a lot of crispness and additional quality to the look of the game."

Gyrling added, "Our goal with the Remaster was to keep it as a 'true' remaster. Even though we had some ideas, we wanted to really just focus on keeping the same core experience. We dove into a couple things, like the new features with the PS4 controller."

Remastered uses the PS4 controller's touch pad to allow you to select inventory items, and the light on the front of the controller will interact with the game as well. Gregory said, "We wanted to take advantage of those things and even at times use the speaker on the controller. So those small things that aren't really major changes still contribute to that true feeling of what we can do on this generation. This is what it means to take this game and not change it, but remaster it and provide that experience on the PS4."

How does multiplayer work?

Put simply, any multiplayer DLC content you bought on the PS3 can be downloaded to the PS4 version at no charge. However, the competitive mode is completely separate on PS3 and PS4; you can't transfer your progress over or play against PS3 players when you're on PS4.

New multiplayer content has continued to come since development began on Remastered, but those additions have not been a developmental roadblock. "It is a challenge, but we've been designing our development process and our software architecture ever since we started with The Last of Us," said Gregory. "The guys who worked on the PlayStation 3 stuff, they check in with new features or weapons or whatever, and we can relatively easily migrate that over to the PS4 version and then get it running pretty quickly."

Why not include a separate install disc?

In previous interviews, Naughty Dog has said that the capabilities of the game are limited more by disc space than the power of the PS4. So it would make sense that putting the high-res textures on a separate disc could help make the game look even better and eliminate any file limit considerations.

"I don't think that really goes along with the way we want the user experience to be. You pop in the disc, and we don't want loading screens, we don't want install screens," Gregory explained. "Even now, we've tried to minimize the time you sit and wait for anything to load. Having a second install disc, it really doesn't jive with how we'd like the user to perceive our game. And I think it goes counter to the design of the PS4 in general. One of their founding principles is this idea of immediacy. The idea that a player can purchase a game, get it downloaded quickly, and get right into the game and start playing. So that's certainly a primary goal on PS4 in general."

Cambier added, "So the biggest challenges in bringing the game to PS4 were, number one, shifting to 1080p movies. But we were able to do that with a slightly better encoder and decoder for the video, so it's actually the same amount of space on disc. The second biggest change was going to four times the texture resolution for our in-game assets. We had to re-architect some of our tools to take advantage of texture sharing and how we deal with that to not duplicate and waste space on the disc. At the end of the day, we were able to get everything we wanted onto the disc, and didn't really have to compromise anything. And that's including the full Left Behind DLC, so it was really a challenge, but we figured out how to get it all in there."

What lessons has the team learned for the next Naughty Dog PS4 game?

"It's like taking a crash course in PS4," Gregory said. "The thing is, because you've got a completed game, that game is exercising the hardware in every possible way you can imagine on the PS3. And when you bring it over to the PS4, we have to figure out how do we make that work in terms of the PS4 technology? Whereas if we had started with just a brand new game, we might not have exercised those things for quite some time. This way we feel like we've got a very complete engine, and something that's going to provide a great foundation for moving forward from Uncharted."

Did the team experiment with adding any potential Project Morpheus functionality?

"We haven't really had any time to experiment and play around with Project Morpheus at this point," Gregory said, "We've solely been focused on getting The Last of Us on PS4 to the point where it is. And that in itself is a huge undertaking. Project Morpheus just looks really promising, and we hope to be able to experiment with it later. At this point however, we're just looking at other studio's awesomeness."

Why should you revisit this game if you played on PS3?

Obviously, Remastered looks better, and some players, myself included, plan on picking it up more as an excuse to finally play on a harder difficulty level. But what about other players? Why does Naughty Dog feel the need to revisit a game that's already done so well? Gregory said, "In my view, this is really the way The Last of Us should be played. When you look at it on PS4, on PS3 we were envisioning something that couldn't quite be achieved. It was very well achieved on PS3, but not quite. And on PS4 it feels like the game reaches its full potential."

The Last of Us Remastered is set to release on July 29 for the reduced price of $50.