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gravitystorm / openstreetmap-carto

A general-purpose OpenStreetMap mapnik style, in CartoCSS
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admin_levl=6 on ZL 9 and 10 #26

Closed lxbarth closed 11 years ago

lxbarth commented 11 years ago

From Toby:

county borders (admin_levl=6) aren't being rendered at zoom 9 and 10. But I do recall some confusion on the existing style between ways and relations. I don't remember the details but there was some difference between the zoom level at which ways and relations tagged with admin_level=6 got rendered. Maybe this caused confusion when porting to carto? Easy place to see this difference: http://bl.ocks.org/d/4271706/#9.00/39.4664/-96.9125

Response from AJ:

This seems to be about boundary relation way members being individually (and redundantly?) tagged with boundary=administrative. Some of the admin_level=6 ways in this area 1 are tagged as boundary=administrative, and others are tagless members of boundary relations. If you zoom out, the tagless ways disappear at zoom level 10 and below.

This commented out section of the stylesheet may be why the CartoCSS version is different:

https://github.com/gravitystorm/openstreetmap-carto/blob/master/admin.mss#L75-L85

gravitystorm commented 11 years ago

As AJ says, this is related to the commented out section in the stylesheet. Re-examining the (curious) filter, the original stylesheet draws solid lines on any boundary that doesn't have an admin_level tag, and only on zoom level 9 and 10.

I don't think this is a good idea, and I can't see any reason why you'd want to do that. Unless someone provides a good explanation, I'm not going to re-instate this rule on the 2.x series.

gravitystorm commented 11 years ago

OK - closing this as per previous comment.