At 2am one auspicious night in 2012, Prague police were horrified to discover that a shady-looking group of Americans had set up some sort of advanced laser weapon on the Charles Bridge, one of the oldest such structures in Europe. "Yeah we were on the Charles Bridge, which I guess is one of their big monuments, with this huge piece of technology," recalls Forza Motorsport 5's content art director Matt Collins. "And we start scanning the bridge and some cops came running up. So we had a couple of our guys detain them while we finished up the scan."
He neglects to explain how exactly his colleagues went about "detaining" the fuzz (we envisage a knee slide followed by a roundhouse kick, but this may be a flight of fancy). "This whole scan was a stealth operation. We told them that we were scanning but - I don't remember what we told them. 'This has absolutely nothing to do with anything nefarious'. They were surprisingly lackadaisical," Collins continues, breezily. "They were like 'oh, okay I guess this is fine.'"
It's possible the enforcers were mollified by talk of Forza Motorsport 5's unheard-of degree of track fidelity, which extends right down to the sight of moss and grass between individual pavement stones. Look up - generally a good idea, when steering a McLaren F1 capable of 231 mph - and you'll see believably animate, fully 3D-rendered crowds, distant yet ultra-detailed monuments ("in the past, this would have been a matte painting") and gorgeous atmospheric effects such as river fog.
It all starts with the tarmac, of course. "We brought a laser scanner to the track and basically scanned every square inch of it actually," Collins explains. "We scanned the entire track and it goes down to sub-6mm accuracy, so it picks up little divots in the road surface, it picks up all sorts of details." This sort of faithfulness applies to both the new tracks and those brought back from older Forzas, such as the Nürburgring. "We do this for all tracks in the game. Even the ones we've shipped before we've gone back and rescanned and updated."
As with the game's impossibly opulent cars, tracks will show the effects of extended punishment - though the ramifications obviously aren't as drastic as they are in, say, an arcade racer like Split/Second. "There's this idea that we're having the 23rd hour of the 24 hour Le Mans - every track really feels like it's really been raced on, it's telling a story as you go round it. So if you've seen the end of those races, there's rubber, there's marbles, it just feels like it's been through a war and we really want to sell that." You'll be able to tell which corners other racers have found particularly troublesome by looking for those desperate streaks of rubber.
Turn 10 chose Prague for Forza 5's debut because the trackside environment is so varied, a challenge worthy of a next generation console. "It gives us an opportunity to showcase so many different things," content director John Wendl chimes in. "Everything from long draw distance to the atmosphere, because it's on the water, to tree canopies like this, to the incredible high-frequency detail of the old buildings and churches and things like that."