Call of Duty: Black Ops 2 doesn't need a brand new game engine to improve the graphics over previous games in the series, Treyarch has insisted. Black Ops 2 is built using the latest, most advanced version of the engine that Call of Duty developers have used to build the first-person shooter series since 2005's Call of Duty 2: a heavily modified version of the id Tech 3 engine. Some fans have called on Activision to invest in a brand new graphics engine in order to spruce up Call of Duty's visuals. But Treyarch chief Mark Lamia said continuing to upgrade the current engine was enough to meet the development team's design goals. "People always ask me, 'Is this a new engine?' he told One of Swords. "I liken it to people who live in an older house that has been remodelled. Just because you're remodelling the house and it will look new or it will have a new kitchen, you don't tear out the foundation, or break out some of the framing. You might even go as hardcore as replacing the plumbing, and we will do that sort of thing, as an analogy. It's a gross simplification, but it's one way to say that. There's a lot of good still in that foundation that you wouldn't get rid of, and we don't. We look to advance in the areas that support our game design.

"Engines, each time they get touched, they change. The creators alter them; they don't modify what they don't need to, and then they alter what they need to. You can't make a competitive product if you're not upgrading that engine along the way." He added: "I think the whole thing about a new engine... sometimes that's a great buzzword. Well, I have a new graphics engine - is that a new engine? Where does it start and stop? Elements of the code, you can trace back for a very, very long time... but whole parts of the code are entirely new. Two areas we did focus on for this game were the graphics and the lighting - a pretty significant amount of work is going into that."When Activision announced Black Ops 2 earlier this month it promised a "visual overhaul", with graphical upgrades a mix of "tech and technique". In a demo to press played on an Xbox 360 build of the game, an unpopulated level set on Socotra Island in Yemen showed HDR lighting, bounce lighting, self-shadowing and a new texture technique called reveal mapping - all running at 60 frames per second.

"I think what people are asking for is for us to push," Lamia explained. "They want us to make a better-looking game; they want things. I don't think those are things people can't ask for. We asked ourselves that very same question - we wanted to advance the graphics. I think the questions are valid. The answer may not need to be an entirely new engine, but you might need to do an entire overhaul of your entire lighting system. "The trick is, we're not willing to do that if we can't keep it running at 60 frames per second - but we did that this time. So this is the Black Ops 2 engine."