Call of Duty 4: Modern Warfare is one of the most successful games of this generation; having sold well over 10 million copies by this point, it serves as an example of the art of making military first person shooters fresh and engaging.

A big part of that puzzle is the art. Creating a believable world that's worth fighting in is one of the biggest challenges, particularly for a game set in contemporary times -- and in a variety of contexts, as the game touches on more than just the battlefield.

Here, Infinity Ward's technical art director Michael Boon, who has worked on the Call Of Duty series back to its original 2003 incarnation, and is currently working on Modern Warfare 2, exposes some of the process behind the game's visuals, and discusses the developer's creative philosophies.

He also discusses the need for technical artists in an increasingly complicated world of triple-A game development -- standing up for those who can bridge the gap between the programming and art staff.

So you're a technical artist?

Michael Boon: Yeah, I was an animator. Most of my skills are in animation. I have done character modeling, character texturing, and programming, so I have little bits of skills in all the areas.

I feel like technical artists are kind of cropping up much more than in the past.

MB: The bigger your team is, the more you need them. We have four depending on how you measure it, I guess.

How do you think the landscape has changed to where you actually need to have a technical artist or even a technical art director?

MB: I think you just play to your strengths, like I work at Infinity Ward and I've been there for a long time, so they wanted to make me a director.

I mean the industry -- how do you think the industry has gotten to where we need this much more than in the past?

MB: I'm not convinced that we do need it. It's just that whoever you have on your team, you put them in the position where they do the best work. It's a position that works well for me. Having said that, you do definitely need technical artists. You need people who can translate between between programmerese and artistish.

There isn't quite the equivalent on the production side, or other disciplines.

MB: We have scripters at Infinity Ward, which at other companies are called gameplay programmers. They're definitely half programmer, half designer. In production, yeah, you're right. Although, at Infinity Ward, we have Jason [West], who is half programmer, half producer.

In general, what does "first-playable" mean to IW?

MB: At first-playable, we look at levels -- we look at several levels, and we try to make them all really good, like virtually shippable. We take a little time from just cranking out assets to really focusing on "what does this level really need?"

Forget the schedule for ten minutes a day and look at the game and say, "Is the game ready to ship? Is this aspect of the game ready to ship? How do we make it better?"

Are we talking single-player style levels, or multiplayer style maps?

MB: We tend to treat multiplayer a little differently, although it's a little similar.

When you're messing with these levels now at this stage of development, what are the logistics of what you're doing? Is it looking for areas that you need to cut back on, or areas where there are exploits possible?

MB: No, we look for areas to cut back on every time we try to introduce anything new into the game. Everything is always a trade-off. We have a schedule; if you're trying out a new feature, you still have a schedule.

So, you put the feature in where you want, and every now and then, you realize that a bunch of stuff you wanted has fallen off the bottom, and so you re-sort it, you always prioritize.

Exploits -- we have testers all the time. We have 15 testers or whatever it is most of the time. And if they find exploits, we fix them, but really, we push on exploits right at the end. We actually bring in people who specialize in exploits.

I guess I'm trying to get at the method you use for polishing, because Call of Duty 4: Modern Warfare definitely felt very polished to me.

MB: We look at polish pretty regularly. We have a bunch of milestones where we look at one level or a couple of levels in this kind of holistic way, and I think that's pretty important. We start it about a year from when we intend to ship.

When somebody plays through the game and writes down everything they think -- you know, "Oh, I like that," or "I didn't like that," or "I fell off this and got really frustrated," whatever it was -- they write down whatever they think about the level, and then they send it out to the designer of the levels; to the whole company.

When a few people do that, you can really improve a level dramatically in the space of about a week. The way we get it polished is just by doing that early enough that we actually have time to fix the stuff.

One of my personal favorite things about Call of Duty 4: Modern Warfare was that it was concise.

MB: I think we learned on Call of Duty 2 that we need to be very careful with our pacing because you can kind of ruin moments by numbing people to them.

One of the big differences for me between 2 and 4 is that with 2, there were still a lot of times where I could just kind of screw around and where I actually wound up going the wrong direction in the level and finding the end of the map, and throwing potatoes at people...

MB: That was fun, wasn't it? I don't know if we shipped like this, but there was a point where the potatoes would stick to people.

They didn't usually, but the guy you were supposed to interrogate, you could get them in his lap.

MB: There was a point there where -- I forget the guy's name, but the sergeant major type guy who was training him -- I had potatoes stuck all over him.

In Call of Duty 4: Modern Warfare, I didn't really have time to screw around, and I always felt like the thing that the game wants me to do is compelling enough that I'm going to do it; I'm not going to go try to get out of the map in order to try and "conquer" it.

MB: That's always been our goal. I think that's just a sign of -- I can't take credit for this myself -- the skills of the storytelling and design team just kind of maturing, and the focus of Call of Duty 4: Modern Warfare being a more fast-paced, focused game.

We put a lot of effort in subtle ways to encourage and inspire the player to do what we wanted them to do through design.

Another thing that helps is the believability of the characters, and you can sometimes get into that uncanny valley with COD4.

MB: I think the trick to gradually traversing it is to focus on going as far as you can with the character model itself. Then look at ways to enhance that model with improving elements affecting it. Such as the lighting, self-shadowing techniques, and other ways to improve not just the model itself but how it's viewed naturally in the world.

With Call of Duty 4: Modern Warfare specifically, we're fighting in war-torn environments and the characters are rugged and dirty, so the "put dirt on it" technique works well.

Putting dirt on things and that sort of stuff, it does work, but then people do sort of recognize patterns and things like that. So, how can you kind of get around that? What's your method for non-repeating textures, and things like that?

MB: Well, first of all, I'll say one of the hardest things we did in Call of Duty 4: Modern Warfare was make people stop putting dirt all over everything. We finally had a lighting engine that was good enough that you didn't need to do any of that. And we're still pushing on this, put dirt on the right places, but don't put heavy dirt on everything.

Yeah, that was a huge deal in Call of Duty 4: Modern Warfare. And still, to this day, we get art applicants, and I'm like, "No, they're still doing it the old way. There's dirt on everything all the time." To get around that, good lighting is key.

In terms of repeating textures, we repeat textures quite a lot, actually. But you usually want to change them up, like you have a texture that repeats one and a half times, and no one's going to see it.

And then you change to something else, and then you change back again, and it's fine. You have a texture that has some really obvious repeating elements, and you put a window on top of one of them, and no one notices the texture repeats.

Do you do a lot of layering or combining of textures, as well?

MB: We do, but that's slow, so we try to do as little of it as possible. I think, generally, most textures in the game have two and sometimes three layers. We try not to go overboard.

From an art perspective - thinking specifically about the end-game or post end-game scenario in Call of Duty 4: Modern Warfare...

MB: The airplane?

Yeah, is it hard to justify something like that? From an art perspective, is it like, "Now we have to generate these assets, too?"

MB: No, that's not how that stuff usually works. We make between two and three times as many levels as people actually see, and due to schedule restrictions or overarching story changes, they just don't fit into the final game or plotline. But we make that decision pretty early on.

Still, there are always some assets that we really like, that look really good, and that we really want to use, and in the specific case of Mile High Club it was just too good to let go. How its purpose plays into the overarching Modern Warfare plotline is still yet to be seen.

So with the intro sequence, where you're riding in the car, was that entirely scripted by hand? Because a lot of those animations were not reused in the game, like someone poking their head out of a dumpster.

MB: I think a lot of those animations, actually, came from that reuse I was talking about -- I mean, not the majority of them, but there was a good chunk of them at the start of the level that we'd actually made for other levels that got cut.

We call that level Coup. When Coup was first being built, it was like the graveyard for animations. We were like, "Oh, we're cutting this animation," but it would work in Coup, and we put it in the background, or we put it wherever. And then, once the level really took shape, we then started making custom animations for it. And now, it's a good mixture.

That's interesting to hear, because some of us who obviously weren't privy to your process at the time were speculating, "How could these guys afford to make this extensive sequence here?"

MB: We have a very good arrangement with Neversoft; they have a motion capture facility that we use. They are a 15-minute drive up the road, and they don't charge us as much as a commercial house would, so we can afford to try things out like that and use them once, and that's really good.

In terms of making sure that you were going to be able to control this IP more and do your own original projects, how has that affected the company and the feeling there?

MB: I think everyone at Infinity Ward feels some ownership for Call of Duty, and we're very proud of it. But at the same time, we knew when we first started talking to Activision that we're making Call of Duty for them; it's their property. So, we accept that. But the more successful we are, the more leverage we have, and the more we can say, "We want to do this next."

I think at this point, we could probably make whatever game we wanted. I think that another thing that would influence their decision to let us do that is that we have a very high internal standard.

And if we started making a game and we didn't think it would sell, even if we thought it was good, if we didn't think it would sell, we would pull the plug ourselves. I think they trust us in that.

During the postmortem for Game Developer magazine, it was mentioned that there was a second project that was distracting for some time, and you made the decision internally to not distract yourselves with it. Is that being revisited now, or is that still in the future? Or not to be revisited at all?

MB: There's no such thing as purely revisiting anything like that. We always have a big pile of ideas cooking. Jason has said, I think, that we'll expand to two teams when it feels right, when we actually have two games worth of ideas that are ready to go, and not just two high concepts that are ready to go.

I think that was the problem last time, we just had a high concept, and when it came down to figuring out the nitty gritty, it took a lot of effort. It does, it takes a lot of effort.

Have you guys ever considered doing anything on a smaller scale? Infinity Ward has always been pretty oriented toward blockbusters.

MB: We talk about it all the time. We're constantly talking about what iPhone game we want to make or whatever it is. But seriously, eh, I don't know. It might happen. There's a lot of people who are excited about it. But there's nothing concrete for sure.