[Tagging] Large areas of landuse=grass in the Netherlands
tomasstraupis at gmail.com
Mon Mar 11 20:38:44 UTC 2019
Some time ago I was proposing to introduce topology rules, at least
locally. Those (besides a lot of other stuff) would cover which
polygons can be above which polygons, which polygons can not be above
which polygons etc. Such rules are already used for years in Lithuania
in regards of forests.
F.e. landuse=forest can not intersect/cover
waterway=riverbank. But for small patches of trees we use
natural=wood, which can ONLY be above (be covered by)
Idea is that for large scale maps you use all of these polygons
(with natural=wood on top) and for small scale maps you simply ignore
This simplifies cartographic tasks a lot. It is also capable of
separating micromapping without the need for complex generalisation
As far as I understand, landcover tags are supposed to be used for
exactly the same tasks (as natural=wood in my example). This means
that all natural=wood polygons in Lithuania (not too much - 1500)
could be replaced with landcover=wood|forest|trees (whatever) if that
was rendered in OSM-Carto, as some people in Lithuania still use
OSM-Carto data visualisation and not the local OSM maps.
If I understand correctly, landuse=grass is the same thing for
grass: landuse=grass is a micromapping (for large scale maps only),
landuse=meadow is for smaller scale (actual landuse) mapping. So you
could have the same topology rules in Netherlands to check
automatically that all landuse=grass is above some actual landuse
(hence the need for landcover to be able to have both). This way there
would be an automated way to check quality of OSM data.
IMPORTANT: There is no way to ensure the quality of OSM data without
automated checks doing MOST of the work.
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