[Tagging] wall and block that aren't a barrier

[Tobias Knerr]

On 09.06.2018 23:13, marc marc wrote:
> https://upload.wikimedia.org/wikipedia/commons/thumb/2/22/Rehbrunnen_04.jpg/800px-Rehbrunnen_04.jpg

Based on this picture, the current mapping is clearly incorrect. This
basin doesn't qualify as a barrier=retaining_wall even if we allow for a
very generous reading of the tag's definition.

For most use cases, I believe it would be entirely sufficient to draw an
area for the fountain, and add subtags as desired. For map users who are
interested in how the fountain looks, the image and wikimedia_commons
tags are already available.

The mapper seems to be interested in going beyond that and creating a
relatively detailed model of the fountain, which is a legitimate goal
and might be useful in some applications, e.g. 3D rendering. However,
I'd argue that our editors and data model aren't really the right tools
for that job. It would seem more practical to create a model of the
fountain in Blender or SketchUp, which could then be uploaded to the 3D
Model Repository and linked with OSM.

If we to try to model the fountain using OSM ways and areas anyway,
though, then I'd rather see specialized tags for fountain micromapping
(nano-mapping?) introduced. Re-purposing existing tags for this use case
isn't a good idea imo.