<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">2017-04-27 13:14 GMT+02:00 Marc Gemis <span dir="ltr"><<a href="mailto:marc.gemis@gmail.com" target="_blank">marc.gemis@gmail.com</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">On Thu, Apr 27, 2017 at 10:03 AM, joost schouppe<br>
<<a href="mailto:joost.schouppe@gmail.com">joost.schouppe@gmail.com</a>> wrote:<br>
> So then you need to decide if a park in a residential area is a park or a<br>
> residential area.<br>
<br>
</span>aren't park and residential area 2 different "layers" ?<br>
<br></blockquote><div>Yes, they were. But my use case was statistical analysis, not any kind of map. I needed to pick just one landuse indication for as much land as possible. So first I made the layers, then cut away areas from the "lower" layers if they were also defined in the "upper" layers. But as you say, that is not always straightforward.</div><div>And yes, I know the OSMlanduse project, though I finished mine before they published anything.</div><div><br></div><div>The examples you give are already hard work to think about. Much more basic mistakes are made too: e.g. a forest is also a nature reserve. But then someone turns the forest into a multipolygon, because there is some water or grassland inside of it. But the multipolygon is also used for the nature reserve. Which would imply the holes in the forest are unprotected, and that's usually not the case.</div><div><br></div></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr">Joost Schouppe</div><div dir="ltr"><a href="http://www.openstreetmap.org/user/joost%20schouppe/" target="_blank">OpenStreetMap</a> | <a href="https://twitter.com/joostjakob" target="_blank">Twitter</a> | <a href="https://www.linkedin.com/pub/joost-schouppe/48/939/603" target="_blank">LinkedIn</a> | <a href="http://www.meetup.com/OpenStreetMap-Belgium/members/97979802/" target="_blank">Meetup</a></div></div></div></div></div></div></div></div>
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