All of the code for converting the 2d Map data into 3d .obj files and other information that is used by Unity to create e.g. street lamps is done here:

https://github.com/Matthiaas/roads.sexy/blob/master/hackatum-2019/src/xodr_viewer/xodr_viewer_window.cpp

All the C# implementation is done here:

https://github.com/Matthiaas/roads.sexy/tree/master/unity_rendering/Assets

All of the visible stuff is loaded at runtime with some scripts. There is nobody actually touching Unity and putting gameobjects into the s cene. Everything that is requiered a camera and a gameobject that starts our script.

Presentation can be found here: https://docs.google.com/presentation/d/1KmHp7f5TuyppNJAbvB4XWwzwemVQYaDhr97cu_p7SSA/edit?usp=sharing