I stumbled upon a real-world example yesterday that may make the attempt to have the level-tag describe a "global" order (as used in OpenLevelUp, JOSM etc.) somewhat impractical - with that level-selector UI element:
So, Hamburg is a really flat city. And even still, the mall "Europa Passage" ... https://www.openstreetmap.org/way/214840502#map=17/53.55223/9.99644 ... does have two "ground floors". If you enter through the northern entrance, you are in the lower ground floor (level=0), if you enter through the southern entrance, you are in the upper ground floor (level=1). If you walk alongside the mall though (Bergstraße), there is no (apparent) elevation. So, imagine there are more indoor-mapped places both around the northern and the southern end of that mall (there is, partly, but I am sparing you the details), and as a matter of fact, sprinkled throughout the entire city centre. Then, to have a global order of things, the ground floor of all the buildings South of that mall would need to be tagged with level=1 and the ground floor of all the buildings North of this mall would need to be tagged with level=0. In other words, must be relative to the level order used in this building. I see two problems with this: 1. Where to stop? How global is this global order? Going further South, at what point does the level-value for the ground floor revert back to 0? What then if two such places collide? (A mall and a multi-level train station were mapped separately and they built a tunnel to connect the two, but they connect on different level=X - or not even a tunnel, let's say they are just next to each other) 2. It is somewhat confusing for the user (and the mapper) because if you look at such a map, at for example level=0, you would see an unexpected split through the city centre where seemingly no building is indoor-mapped South of that mall ... oh wait, it's all on level=1+. ??? I, too, hope that the example was understandable. Tobias _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
