A fleet of 300 cars is methodically criss-crossing major cities around the world, documenting our streets in painstaking detail. They aren’t Google’s Street View cars, but Nokia’s Here True cars, similar vehicles with a slightly different goal. Nokia wants to create the next generation of extensively detailed 3D maps through “reality mapping,” and it could be big business for the company over the next decade. The maps will be able to do things like tell driverless cars everything about the road they’re navigating, from where the street markings are to how fast other cars typically take a corner.