"Everybody wants perfection," says Turn 10's vehicle art director Gabriel Garcia, "and we delivered perfection in Forza 4." It's a claim that obviously threatens to render Forza Motorsport 5 a little surplus to requirements, but Garcia has a nifty canned follow-up. "How do you improve on perfection? You actually make it imperfect. Because perfection is not authentic, it's not real."
Besides killing off old concepts of single player AI with the Drivatar system, Forza 5 aims to portray a different standard of beauty to last generation predecessors. Its garage of impossibly expensive cars aren't just mouth-wateringly handsome - they're palpably, beguilingly made, alive with tiny discrepancies and blemishes inflicted during the manufacturing process.
Look at a disc brake in just the right light, and you'll make out faint scratches where the component left the press. Zoom in on a tyre, and you'll be able to see where the Armor All's rubbed off against the road. Paint jobs are very finely pitted (the infamous "orange peel" effect) to reflect the limitations of even the most advanced industrial spraying techniques. The same attention to detail applies to the innards of the car. "You've got areas of the car where you have a swath of leather and it's smooth and looks nice," says Garcia, "but when the light hits it you see just minor variations of colour and value and depth to the surface."
The visual benefits won't be obvious at a glance - indeed, that's the whole point. Turn 10 hopes the sheer depth of its fine-tooling will endow automotive buffs with a new appreciation for the subtleties of car creation, such as what separates a car designed for a showroom from one that isn't. "What's the difference between the two?" Garcia continues. "Well, they put the functional stuff into a cast, and they knock it out of a cast and that's how they ship the product, so you get this roughcast look, it's very pitted, it's not smooth.
"Other parts of the car that the manufacturers intend you to look at and show off, they'll spend a bit more time on it - sand it down, smooth it out, paint it a little nicer. That's the kind of thing that we've introduced to our cars. It's all that minor imperfection that goes into a beautiful, perfect car. Get a little closer, and you realise all these things are contributing to that beauty."
This level of care and attention is possible, naturally, thanks to Xbox One's substantially superior RAM allowance. To put it all in hard numbers, Forza 4's cars were composed of between 54 and 60 unique materials. Those of Forza 5 are composed of around 1300, and Garcia insists that "we haven't hit the limit of what we can do".
The jump to Xbox One has necessitated drastic changes in methodology. "What we did was take all our knowledge from ten years, making four versions of Forza, and we just did a complete redesign of the entire production process, and our methods, and from the ground up we redesigned the way we're going to build cars," Garcia explains. "We changed it up and while we kept a lot of the good things, we've improved on other things that allow us to put more depth into our content."
The studio has ditched all existing car assets and started afresh. "That's one of the challenges of developing for a new console," adds Bill Giese, design director. "We had to rebuild every asset in the game. Unlike previous versions where we could leverage things and move them over, everything's all-new in this console."
This has entailed a considerable manpower investment. "We have a team across multiple countries, hundreds of artists, putting thousands of man hours into our content. One of the things we did as part of this new production process is we now have specialist artists who focus on very specific areas of the car that excel at what they do."