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Published 20 hours ago • verified publisher icon openmaptiles

Landcover/usage vectorised incorrectly when split into smaller chunks

Open ntadej opened this issue 3 years ago • 4 comments

Slovenian landcover/usage is split into 2x3 km rectangles. When this is parsed from OSM it causes rendering on small zoom levels as tiles think it's a small polygon.

Can be observed on MapTiler: https://data.maptiler.com/downloads/dataset/osm/europe/slovenia/#7.1/46.155/14.993 Screenshot 2022-01-10 at 22 06 54 Screenshot 2022-01-10 at 22 07 25

The third screenshot is OSM directly: https://www.openstreetmap.org/#map=9/46.2064/14.4333 Screenshot 2022-01-10 at 22 09 54

Should these rextangles be merged in OSM or can something be done here?

ntadej avatar Feb 09 '22 21:02 ntadej

Seems to be related to #1035 (but it does not seem to be working for Slovenia).

ntadej avatar Feb 10 '22 07:02 ntadej

Merging them in OSM would result in some huuuugeeee multipolygons, making them near impossible to edit.

A similar issue #201 was raised previously and I mentioned Slovenia in the comments, but apparently it was fixed only for higher zoom levels.

stefanb avatar Feb 10 '22 08:02 stefanb

Thanks for pointing this out. This should be part of the processing (fixing) landcover layer (e.g. use other filter then area). Any help is very welcome.

TomPohys avatar Feb 10 '22 08:02 TomPohys

@TomPohys do we know how maptiler globallandcover is generated? i feel like somehow the did it better there. maybe check that region to see if we see the same thing there at zoom 9

farfromrefug avatar Feb 13 '22 08:02 farfromrefug