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<div class="moz-cite-prefix">On 29/07/18 20:37, Paul Allen wrote:<br>
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cite="mid:CAPy1dOJcDJFAtPap8G7ZgZ5VWj9XD6LnMPGAMkUXssbt1Wcw9Q@mail.gmail.com">
<div dir="ltr">On Sun, Jul 29, 2018 at 12:57 AM, Graeme
Fitzpatrick <span dir="ltr"><<a
href="mailto:graemefitz1@gmail.com" target="_blank"
moz-do-not-send="true">graemefitz1@gmail.com</a>></span>
wrote:<br>
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<div>The problem with that of course, as Warin
mentioned, is what would it hypothetically render
as - grass / sand / rock / scrub etc etc?</div>
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<div>If you simply define an area that is absent of woodland
with no tags defining what it is, then it renders as an
absence of<br>
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<div>woodland. It is a hole in the woodland that renders
the same as whatever is outside the woodland, i.e., bare
map. It's<br>
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<div>only if you add tags to the inner area that define it
as grass/sand/whatever that it renders as anything other
than "bare<br>
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<div>map." Or if there's a larger area enclosing the wood
(such as a nature reserve) then the hole will (I haven't
tested that,<br>
so make it "should" rather than "will") still render the
same as outside the wood.<br>
<br>
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<div>I've poked holes in a wood to handle clearings, and
poked holes in woods for ponds and quarries. It all works
fine. If<br>
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<div>you don't trust me then give it a quick try. It's a
matter of minutes to add a relation to the wood, transfer
the tags from<br>
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<div>the wood to relation, then add one of the clearings to
the relation and see what happens. If you hate the result
then<br>
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<div>it's only a few more minutes to manually revert.<br>
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<br>
I too have created relations for tree areas and made 'holes' in them
for various things. Some of those 'holes' may well be 'bare map'.<br>
The level of detail gained is proportional to the time taken, the
resolution of the imagery and lack of cloud cover in the imagery. <br>
Fortunately there is now more than one good image source so clouds
are less of a problem. <br>
<br>
The problem with the present data in this area is that;<br>
<br>
a) it does not render so 'we' don't know it is there by looking at
the rendered map.<br>
<br>
b) it was done remotely using imagery .. so even the mapper did not
know what really was there, other than a lack of trees at that time.
<br>
<br>
c) HOT mapping may be speed driven, to get usefull data quickly to
places in need, rather than good mapping.<br>
<br>
<br>
The problem is the presence of the tag 'landuse=clearing'<br>
that apparently, from both imagery and language, simply mean a lack
of trees compared to the surrounding area. <br>
It is quicker to map these 'holes' as they are much less in length
compared to the outer way. <br>
The 'landuse=clearing' says nothing about what is inside the area ,
other than the lack of trees, it could be dirt or grass or any other
thing or things. <br>
To my mind that tagging can be replaced with these 'holes' in a tree
relation as detailed above. <br>
OSM looses nothing by removing the tag provided the way is
incorporated as an inner in a tree relation. <br>
If a mapper wants to look at an individual way .. then the history
of that way is available, so they can see it came from
landuse=clearing and who the original mapper was. <br>
I could add a tag - say a "comment=from HOT contribution, tagged
landuse=clearing" .. that should suffice. <br>
<br>
In OSM 'we' try to tag what is on the ground, "landuse=clearing" to
me means a lack of something - not what is there, but what is not
there. <br>
And that is not something I'd even think about trying to render. <br>
<br>
------------<br>
Some time ago I tried to improve the mapping of the Kokoda Trail.
That included the tree relation 7575948<br>
<a class="moz-txt-link-freetext" href="https://www.openstreetmap.org/relation/7575948">https://www.openstreetmap.org/relation/7575948</a> <br>
That does show the 'holes' where what is there has not been mapped
because it cannot be readily identified for aerial imagery. <br>
Note: The Kokoda Trail is mapped as a 'road'. No motor vehicle has
ever been over it, other than in an aircraft. <br>
Even a bicycle would not be a good form of transport of it. In WW2
the Japanese did not take bicycles on it, one officer took a horse..
they killed it. <br>
<br>
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