Going on from what R.S has said, there's some tricks.
The culling purposes, the cars have different model tags depending on what camera you're using.
For example, there would be an 'interior' tag for some meshes, just the entire interior HQ model, the hood, the spoiler, and anything visible from the interior view. Things like outside door panels, wheels (in most cases), etc would not be rendered by the camera tagged 'interior'. So on a camera-by-camera basis they can pick out what to render by assigning bits a different tag or 3.
That interior 'layer' is then drawn on top of the rest of the scene (track, other cars, smoke, etc), helping to avoid front brake lock-up smoke from going into the cabin, and keeping the rain drops outside the windscreen.
There's also the ingenious materials system they've put in place for the thousands of colours. For each car they'll have a
normal map (the cars is mostly smooth, so this is for bumpy bits like Carbon Fiber, door handles, key holes, fuel fillers, etc), everything else I imagine would be basically that one blue tinge.
AO map (for good lighting around detailed areas)
diffuse, now this is the nice bit. It looks like it's be one pixel, one defined colour!
Spec, this is a tricky one, but I think they're giving it another colour (what colour you get in the light, AND another value for how shiny it would be
As well as whatever cube maps and what not they're tossing on.
They're probably all compiled from layers into several (4 or 5?) materials that are applied to the car when the car painting animation plays!
The culling purposes, the cars have different model tags depending on what camera you're using.
For example, there would be an 'interior' tag for some meshes, just the entire interior HQ model, the hood, the spoiler, and anything visible from the interior view. Things like outside door panels, wheels (in most cases), etc would not be rendered by the camera tagged 'interior'. So on a camera-by-camera basis they can pick out what to render by assigning bits a different tag or 3.
That interior 'layer' is then drawn on top of the rest of the scene (track, other cars, smoke, etc), helping to avoid front brake lock-up smoke from going into the cabin, and keeping the rain drops outside the windscreen.
There's also the ingenious materials system they've put in place for the thousands of colours. For each car they'll have a
normal map (the cars is mostly smooth, so this is for bumpy bits like Carbon Fiber, door handles, key holes, fuel fillers, etc), everything else I imagine would be basically that one blue tinge.
AO map (for good lighting around detailed areas)
diffuse, now this is the nice bit. It looks like it's be one pixel, one defined colour!
Spec, this is a tricky one, but I think they're giving it another colour (what colour you get in the light, AND another value for how shiny it would be
As well as whatever cube maps and what not they're tossing on.
They're probably all compiled from layers into several (4 or 5?) materials that are applied to the car when the car painting animation plays!