Is it possible to draw simple shapes (like spheres, rectanges) into the simulation without adding a 3D object?

Hello, we are developing an addon, which must be able to draw simple shapes to specific coordinates. These coordinates are calculated relative to the camera/aircraft and always changing, therefore including a 3D object into a specific scenery is not an option. The addon should work with any aircraft, so including a 3D object into our own aircraft is also not an option.
A simple example: let’s say in VR we want to show where the user is looking at by drawing a sphere into the sim and updating its position (redrawing it) in realtime.
Is something like this possible?
Thanks!

With a mission script, you can place objects relative to the users’ plane or other simobjects, but I’m not sure how you can get the position and orientation of the camera.