It’s an open secret that Apple is working hard on both self-driving car and augmented reality technology. CEO Tim Cook has hinted at it heavily in the past, and even if he didn’t, it’s virtually a given that the world’s most valuable tech company would be working on two of the biggest upcoming tech breakthroughs.

A new patent filing discovered by AppleInsider shows how Apple could merge the two technologies into one, or at least use AR to support the passengers in an autonomous vehicle.

The patent is for an “adaptive vehicle augmented reality display using stereographic imagery,” and it would combine data from the vehicle with a premade 3-D map of the world to provide passengers with in-depth information about their surroundings. The abstract describes an “AR system that leverages a pre-generated 3D model of the world to improve rendering of 3D graphics content for AR views of a scene,” with the specific example being “an AR view of the world in front of a moving vehicle.”

“By leveraging the pre-generated 3D model,” the patent says, “the AR system may use a variety of techniques to enhance the rendering capabilities of the system. The AR system may obtain pre-generated 3D data (e.g., 3D tiles) from a remote source (e.g., cloud-based storage), and may use this pre-generated 3D data (e.g., a combination of 3D mesh, textures, and other geometry information) to augment local data (e.g., a point cloud of data collected by vehicle sensors) to determine much more information about a scene, including information about occluded or distant regions of the scene, than is available from the local data.”

A good visualization of what the system could provide is shown in one of the patent drawings. The image shows how the AR display could trace out and provide information on things of interest that are currently out of view, such as the path that the road takes behind some trees or buildings.

Beyond what Apple describes in this particular patent, there are all sorts of useful applications for AR in autonomous vehicles. Companies could use an AR display to show passengers what the car is “seeing” on the road with its sensors, which would help to set occupant’s minds at ease, and could be particularly useful in the transition period to fully self-driving vehicles. Down the road, AR could also be used for media or advertising.