"It's the whole dynamic nature of the game. Nothing's baked, nothing's faked. We run everything real-time, and some of the demonstrations I've done you can speed the time-of-day to up to 500 times and see all the clouds roll by," Perkins continues. "We've got a fully volumetric cloud system. You play the same track 20 times in a row and you'll get a different sunset every time. It all feeds back, and because of the atmospherics and the draw distances it's all mixed in - from the cars to the roads to the mountains to the skies."
"One thing you can see, everything's reflected in the road surface. We're not doing this just locally to the track surface. You can fly out as far as you like. It goes all the way to the top of the mountain, so if the sun pokes through you'll get massive highlights where the rock formations are. And of course all the materials interact differently. The grass gets wet differently to the rock, which is different to the tarmac, which is different to the plastics."
To achieve DriveClub's consistency in lighting, reflections and effects across the world, a materials-based system is in place across all cars and tracks. Every surface is built to reflect light according to real-life values; a time-consuming process that - according to the team - means each car takes up to seven months to produce.
"We'll be adding things like screen-space effects to actually get all the water droplets on the screen. We'll get the wind-screen wipers working [too], that'll have a full simulation pass so that you get proper droplets," Perkins explains, using his own, private debug build to demonstrate. "It's all modelled. Because of the atmospherics system, everything has to be modelled. It all sits in and writes at the same level. It's one of those things that's really subtle and helps tie it all in."
The game's 1080p resolution is put to effective use too, producing one of the cleanest grades of image quality on PS4. And yet Evolution isn't content to leave it there, backing this full HD setup with an excess of techniques to tackle aliasing from every angle. Asked what anti-aliasing is fit for purpose in this case, DriveClub takes a no-compromise approach.
"It's a mixture. There's a pixel-based system that we're using, there's a temporal-based system, there's FXAA and there's actually a material-based system as well. We've only got four systems in place and we've got another for the key points that we don't quite hit. We obsess about the small details, so we're getting another one to go on top of that, to get on top of the very final image quality issues."
"The latency is as small as we could possibly make it. One of the things we [also] did when we were coming up with the PlayStation 4 itself was work heavily with the guys designing the controller, to make it much more responsive and much easier to use with driving games as well."
Topping the bill of DriveClub’s attractions is the post-release weather update. It's more than a skin-deep addition - vehicle traction alters as the road becomes more waterlogged.
Materials on cars and tracks use physically-based rendering, with plastic, metal and rubber surfaces impacted accordingly by DriveClub’s lighting engine.
Effects such as raindrops are simulated across a car's bonnet and windscreen, with droplets set to visibly wipe away while in cockpit view.
The fjords of Norway show off the incredible draw distance to Evolution's tracks. Thankfully, the pop-in seen in its pre-alpha state is no longer an issue.