Can you personally see the difference between the PS4 and Xbox One versions running side by side?

If they’re running side by side, some people will, some people won’t. The 720 on Xbox One is upscaled to 1080p as far as resolution is concerned – some people have noticed and some people haven’t. I think it’s an individual call. Maybe it’s a close call and maybe it’s not for some people. It really depends on how hyper-aware you are of things like that.

Do you think most people will notice?

If you bought one version or the other it looks great, and that’s how most people will experience the systems – they’re going to buy one and they’re not going to buy both, necessarily.

So I think people will see the new game and think ‘wow it looks great’ – tons of new graphics features, all next gen and that’s how I think it’ll happen. As far as, like, if people start doing side by sides, I don’t know. I mean, I’m sure once the game and next gen launches and people start doing the comparisons – you know, like making YouTube videos – but I don’t know if people will really be able to tell that much difference.

To be honest, we’re kinda gonna have to wait and see. We’ve never done, specifically, a comparison of any sorts. So we have both systems and we can set up those at any time, but it’s something we didn’t purposely try to compare, we’re just concentrate on making each one, not trying to compare each one.

So the big question is why the difference?

When it came down to optimizing for each system, in order to maintain 60 frames per second, which is something we absolutely positively did not want to encroach on, that happened, basically. It was over a period of time and it wasn’t some, like, event sort of thing. It was just happening.

So does that suggest that it’s easier to get that higher level of performance from PS4 than it is Xbox One.

It might. It also just might be the path we took, you know? This is the first game on the console and there’s a lot for us to learn with the new hardware so it’s a long-running process – you compare COD 2 to COD 4 it’s a massive leap forward in graphical fidelity. So I think we expect the same thing on both platforms.

A lot of people are taking this as confirmation that Xbox One is the weaker console and PS4 is more powerful. Is it that simple?

It’s a much more complex answer – there’s so much to it, it’s a balancing act when you get into optimisation – we need more time with it all, basically. It could be years from now until we get to the point where we feel like we’ve maxed out what we can do on both platforms.

And it’s not just hardware physically, the amount of resources that each system is allowing the game developers to use isn’t the same. So from our standpoint that’s something that could change, y’know? We might get more resources back at one point. And that could make things change dramatically for the Xbox One, for instance. It’s a long complicated road that will take years to develop, and I think at the end we’ll have games looking very similar, usually, on both systems.

Some are also asking if you’re able to patch the game to bring the two versions in line with each other – is that something you’d consider? Is that actually possible?

I don’t know if it’s possible to be honest. It’s not something we’re going to look at right away because we have higher priority items we have to hit first. Launching, especially with a whole new backend and so many different changes to our networking etcetera – there’s a lot for our engineers to do post-launch but I don’t know if they’ve even thought about where we could go with a patch like that. I actually don’t even know if it’s possible.

So if you had all the time in the world, would you be able to get the best from both consoles and each version would be equal?

Potentially, yeah but it takes years and years and years to get there. Modern Warfare 2 looked better than COD 4 and Modern Warfare 3 looked better than Modern Warfare 2. With every game that comes out the jump become smaller and smaller but it always looks a bit better every time. Again that’s part of learning the systems and getting better at using them.

So you see this being a continuing trend? Will PS4, being the easier console to work with, end up getting the better looking games in this launch window?

I don’t know but overall I do know that other companies have been saying that they’re also 720 on Xbox One – BF4 was 720, Titanfall has already said they’re going to be 720 on Xbox One so it seems to be the dominant direction at the moment, but so much can change.

By the way, it’s also not just us learning the systems better, it’s Microsoft developing more from the systems as well so if it improves the SDKs on their side we could see improvements, or if they could patch their software then all of a sudden we could get a performance boost out of that. It’s a very complex ecosystem.

COD is very much tied to the Xbox brand – has this caused problems between you and Microsoft, given that the PS4 version is better looking? 

[laughs] It makes us tread lightly, obviously. Regardless of the situations, we never want to really be negative towards any of the consoles so yeah it is obviously a tricky situation. But it’s not one that’s specific to this incident or specific to our relationship with Microsoft. We always want both the systems to be good and actually from our perspective having the two systems, having them compete and drive themselves to be better through that competition…we’ll see a lot of cool stuff come from both sides of the fence because of that competition.

Also, in general, the studio itself is pretty removed from the business aspect of Call Of Duty so we’re not always necessarily engaged with anything like that, the relationship stuff. We try to keep that stuff as separate as possible.

So you’re the Call Of Duty guy among your circle of friends, right? Which version are you recommending to your friends as the best one to get, given the resolution difference?

[laughs] It depends on the friend actually – to be honest it’s really not about which version you think is better, it’s more about which version you think is going to have the better experience. For instance, if I buy one system and all my friends are on the other system, that’s not as good an experience.

So for instance I do have their friends, they’ve made up their mind which system they’re getting, and I’ve had a few friends that have asked for codes who are PC guys and that’s where they’re playing and that’s where they’re going to stay.

Some people really like the Microsoft experience and some people really like the Sony experience. I don’t know how much we’ll see of people crossing over from their preferred family. I’m actually really curious to see how that plays out. But I couldn’t recommend a specific console over another, I think people will figure that one out.

http://www.edge-online.com/news/spot-the-difference-infinity-wards-mark-rubin-on-next-gen-call-of-dutys-resolution-disparity/

Creating a next-gen launch title sounds like a nightmare. Can you explain exactly the challenges you faced?

Mark Rubin: It is for our engineers, especially. Fortunately, both Xbox One and PS4 are very much like PC, more so than the last generation. That helped enormously. If the systems had their very peculiar architecture, like they did in current gen, this would have been a different conversation. But because of that the development this time around it was significantly easier. I have experienced the current-gen launch. I was at Infinity Ward for COD 2. When we launched it was just PC and Xbox 360, but that was our first console, period. There was a lot to learn leading up, but that was just one console, when all it was was PC and that new console. And that was an interesting challenge.

So to do PC, current-gen two SKUs and next-gen two SKUs, was a massive challenge. Working with the theoretical hardware would have been a disaster if... honestly, the hardest thing to deal with is not the architecture. It's the OS (operating system) of the systems. That's the thing that comes on the latest. The Xbox One's OS on their box versus the Sony OS, becomes the hardest. All the SDKs and stuff you have to work with - that's the stuff that changes, not the hardware itself.

What about the operating systems, exactly, is the problem?

Mark Rubin: There's stuff in the console's OS that interacts with the game. So, for instance, voice chat is often supported by the hardware manufacturer rather than the software, and you're just using their channel. When that stuff is changing - because they're developing it on their side - and the resources they're using are changing - your, from a game design standpoint, challenge is with trying to make enough room for those resources to be used but at the same time use as much resources as possible.

One of the greatest challenges the engineers have to deal with is memory management, or thread management. There are X number of threads in your CPUs. Where in those threads is the stuff that's Microsoft or Sony? Where does it fall? How does it work? We don't have the SDKs for those features yet, and then they come in and you go, okay, well it needs 3MB of RAM - oh, crap, we only allocated two! You can't just take a MB from anywhere. It's not like there's just tonnes of it just laying there. You have to pull it from something else. And now you have to balance that somewhere.

It becomes a massive change internally for our entire engine, if they add a few MB to the amount of resources they need, or if they require all their processes to be on one thread. If it's not multi-threaded then we have to put it on one thread. Now we have to find space on one thread, where that can live, that it's not creating a traffic jam on that thread. Sometimes we have to be like, okay, we have to move all this stuff over to a different thread and then put that in to that thread, just to manage traffic.

That's what engineers are often doing: managing the traffic of CPU threads and memory and where that's going, allocating memory, what kind of memory is it? Is it dynamic? Sometimes what has to happen is we have to allocate the 3MB straight off the bat and just say, these 3MB, specifically, these actual memory addresses, have to be used for this. They can't be used anywhere else. Whereas dynamic, it's like, okay, I need 3MB but it doesn't matter where those 3MB come from.

So all that stuff can change on the fly. And you're trying to develop your system to match with that, and it's two systems, now, not just one: Sony and Xbox. That creates a massive engineering nightmare.

Wow. It sounds harder than I realised.

Is all that you've just described the reason the Xbox One version is native 720p and the PS4 version is native 1080p?

Mark Rubin: In a way. I don't know if I can point to one particular cause. Early on, we didn't know where exactly the resolution of anything would fall because we didn't have hardware or the software to support it. We tried to focus in on 1080p, and if we felt like we were on borderline of performance somewhere... We tried to make the best decision for each platform that gives you the best-looking game we could get and maintains that 60 frames a second.

There's no specific, oh, well, the VO chat on Xbox took up so much resources that we couldn't do 1080p native. There's no definitive one to one per se cause and effect. It's just an overall thing. We took each system individually and said, 'okay, let's make the best game for each system.'

I think both look great. Some people might notice if they had them right next to each other. Some people might not. The Xbox One is 1080p output, it's just upscaled hardware wise.

It was a late decision, too. That call wasn't made until a month ago.

Put me in your shoes when you were told this was going to be the case. I assume your engineering team explains to you this is the way it has to be. How did you guys react internally? Could Microsoft engineers not have helped?

Mark Rubin: It's not a thing, like pointing to the day he came and said... It wasn't like that. It's a long process. And we're always working with both platforms. There were Microsoft engineers there throughout development. They were always there. There wasn't an event, per se. There wasn't a meeting. It was just something that developed over time. Everybody was involved.

Obviously the PR guys, when they found out, when they were told, that was more of an event than the devs sitting at work working on it. So you'd have to ask them.

What everyone will ask is whether this is the result of the Xbox One simply not being as powerful as the PS4, and you're doing your best with the hardware you have, or whether for future versions you may be able to get the Xbox One version running natively at 1080p?

Mark Rubin: It's very possible we can get it to native 1080p. I mean I've seen it working at 1080p native. It's just we couldn't get the frame rate in the neighbourhood we wanted it to be.

And it wasn't a lack of effort. It wasn't that it was like last minute. We had the theoretical hardware for a long time. That's the thing you get pretty quickly and that doesn't change dramatically. It was more about resource allocation. The resource allocation is different on the consoles. That huge web of tangled resources, whether it's threads-based or if it's GPU threads or if it's memory - whatever it is - optimisation is something that could go theoretically on forever.

I definitely see slash hope both platforms will look way better the next time we get a chance at it. As an obvious analogy - and if people are not sure about this it's pretty simple - look at Call of Duty 2 versus COD 4. It was a massive leap forward in graphics, and that's just because it takes time to get through this.

First launch, first time at bat at a new console is a challenging one. That's just the way it is. For people fearful one system is more powerful than the other or vice versa, it's a long game.

http://www.eurogamer.net/articles/2013-11-04-xbox-one-resolutiongate-call-of-duty-ghosts-dev-infinity-ward-responds

The OSs was the biggest issues... memory management and multi-threaded CPUs too... some issues with the voice chat too.

pokoko said:

No, he was using voice chat as an example of something that wasn't a problem (or, at least, a big problem).  It was just written poorly.  It should have been something like:

"There's no specific, "oh, well, the VO chat on Xbox took up so much resources that we couldn't do 1080p native." There's no definitive one to one per se cause and effect. It's just an overall thing."