Turn 10's Creative Director Dan Greenawalt will tell you Forza is about turning car lovers into gamers and gamers into car lovers. Except that's not what it's about. Instead, Forza is about maths: it's about throwing numbers at everything from the way light hits your car to how your tyres flex.
When new Brit studio Playground Games started work on Forza Horizon they did it with Greenawalt's vision in mind, but with that maths as the foundation. That's how, in just two years, Playground have made the best-looking and best-handling road racer you'll ever play. While Microsoft's demo pods at E3 are running just the one car - the new Dodge Viper - with every possible assist turned on, you can play Horizon with the full Forza 4 handling model, or with any setting in between. Every car has been custom-tuned for on-road racing, but that's as far as Playground have gone with simplifying Forza's raw science.
"Why would you mess with Forza's physics?" says Playground's Design Director, Ralph Fulton. "It's absolutely best in class. Forza's physics system updates 360 times every second and we haven't compromised that; that level of fidelity is absolutely essential to capture what the cars are going through as they go over the variety of surface types you'll find in our Colorado. We have 65 different surface types; there's no such thing as 'just asphalt' or 'just dirt' - there's so much in between. We've tuned the cars for the road but that's it. You can switch off traction control, ABS, set steering to Simulation, and that experience will be as real as you can get."
A former member of Codemasters' Dirt team, Fulton pitched Horizon to Dan Greenawalt back in 2010. "There's some physics involved in this," says Greenawalt, "and I love physics. We set out to build the best racing studio in the world at Turn 10 and we're based in Seattle, so it's easy to bring in talent from North America but not so easy to bring in talent from the UK, Spain, and all over Europe. The UK has fantastic development talent; I've been playing British racing games since Geoff Crammond! Games like Dirt, Grid, Project Gotham... if you set up a racing studio in the UK and attract British talent it's going to become an amazing studio very quickly so long as it has the right leadership. Playground were the right guys to do that."