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Tagging coastline

0

What is the use of adding tag place=island/islet to a small coastline polygon?
Namely, if a coastline polygon is not inside any other coastline polygon, certainly it is an island because it is "...completely surrounded by water". So, the tag is obsolete. In large number of cases the tag is added to polygons, topologically/formally, never surrounded by water causing logical errors. By the way, the same question could be asked regarding the coastline orientation request.

asked 06 Jun '18, 05:58

sanser's gravatar image

sanser
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One Answer:

3

Not everything in OSM is logical or consistent. Some of it is just so for historical reasons or for making certain uses slightly simpler. The orientation requirement for the coastline, for instance, allows drawing the water (or land) when you only look at part of the data (like a single tile). Without it you don't know which side is which without looking at the larger picture.

answered 06 Jun '18, 09:39

Jochen%20Topf's gravatar image

Jochen Topf
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