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Look at the two consequtive zoom levels


In the level 10 the green (assume forest) on some islans disapear but not on the other land areas. Is there a special reason for that?

asked 27 Feb '13, 22:06

sanser's gravatar image

accept rate: 5%

edited 28 Feb '13, 10:16

gormo's gravatar image


This is an issue in the data, not in the rendering.

Problem : this island is modelized two times.

First time with a single closed way (polygon) tagged with "natural=land":
and being part of the relation "Lake superior" as "inner" polygon:

Second time with several polygons or simple ways:

being part of 3 relations of type "multipolygon" as "outer" and tagged with "natural=wood":

As you can see, the same surface is identified twice as "natural=land" and "natural=wood". Then the renderer will probably select only one of them, depending how the order of the data is processed and the rendering styles which varies at the different zoom levels.

To fix this, a better modeling would be to delete the 3 artificial polygons, keep only the coastline ways, remove the tag "natural=land" in the Lake superior" relation (but keep its "inner" role), and merge the 3 "natural=wood" multipolygon relations into a single one (with the same tags).

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answered 28 Feb '13, 10:18

Pieren's gravatar image

accept rate: 15%

edited 28 Feb '13, 10:19


Is any of the QS tools able to detect such problems?

(28 Feb '13, 11:58) mmehl

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question asked: 27 Feb '13, 22:06

question was seen: 3,091 times

last updated: 28 Feb '13, 11:58

NOTICE: is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum