Reflection lines are lines observed on a surface from tube lights. Car designers employed this to see the surface quality. Usually, parallel fluorescent tubes are placed above the car model.
But this is quite common in Germany.
This is Berlin Hauptbahnhof (main station). The large part of building is transparent (glass). Steel frames are aligned regularly on the ceiling. These are not fluorescent tubes, but reflection line only requires regularly arranged lines. If there is something specular surface, we could see reflection lines.
Please look into the widows of this train. We could easily see that each window has a different quality. Most of the windows did not connects smoothly between windows.
Link to the explanation slides
 Mario Botsch, Mark Pauly, Leif Kobbelt, Pierre Alliez, Bruno Levy,
Stephan Bischo, Christian Roeossl, ``Geometric Modeling based on
Polygonal Meshes,'' EG2008 Tutorial, 2008
 Takashi Kanai, Yusuke Yasui, ``High-quality Display of Subdivision
Surfaces on GPU,'' IPSJ 47(2), pp.647-655, 2006 [in Japanese]
1 week ago