<html><head></head><body bgcolor="#ffffff" text="#333333" link="#0000ff" vlink="#333333"><div>El dj 30 de 03 de 2017 a les 11:40 +0200, en/na Martin Koppenhoefer va escriure:</div><blockquote type="cite"><div dir="ltr"><div class="gmail_extra"><br><div class="gmail_quote">2017-03-30 11:14 GMT+02:00 Lluís Vicens <span dir="ltr"><<a href="mailto:lluis.vicens@udg.edu" target="_blank">lluis.vicens@udg.edu</a>></span>:<br><blockquote type="cite"><div> As far as I know, I think there are no modifications by other mappers on the existing buildings from 2010 to now.</div><div></div><br></blockquote></div><br><br>I find this hard to believe. We are talking about a 7 years period. If this was true, there was no mapping comunity at all in your town. I have looked at some occasional buildings and instantly found buildings with different versions, but many building modifications don't even create a new way version (moving of their nodes!).<br></div></div></blockquote><div><br></div><div>There is community of course! ;-) I wanted to express the idea that "buildings" are map entities that I believe are no intensively edited such as streets and commercial activities are. Specially because the original shapes come from the municipality and editing these features without another cartographic source it's hard to believe. Anyway, I catch your meaning and what you want to say. And probably are more edits that those I've checked.</div><div><br></div><blockquote type="cite"><div dir="ltr"><div class="gmail_extra">Looking at the area with overpass, I found 186 ways and relations with a building:levels tag, there are also particular buildings like churches with significant amount of versions (and a source tag by the municipality).<br></div><div class="gmail_extra"><br></div><div class="gmail_extra">Clearly, removing all formerly imported buildings wholesale and readding the new version is not something you should do in any case (hides the history, ignores community contributions). If there was agreement that it would be desirable as a result, the actual editing approach would still be different: you should take the existing geometry and modify it accordingly to account for differences compared to your new version, but still in this case, you should not modify anything that was since modified, removed or added by the OSM comunity, unless you perform a survey and verify that the new version is better. You have the huge advantage that all your internal ids for the old versions are available in OSM (if I don't misread the "local code" tag), so conflation should be possible in all cases where no modifications have been applied.<br></div></div></blockquote><div><br></div><div>Then, if an automatic or semi-automatic update of the buildings for the whole area of the municipality is not possible at all, I will explain this to the municipality because I don't know if they can plan some sort of a building to building checking process. Please, believe me when I say that I deeply respect OSM mappers and its work (in fact, I'm one of them), and I don't want to underestimate all the work done, but I think it is a pity (from my perspective, of course) because I truly believe that could be a good way to improve the existing data with a more accurate one, coming from what is really registered in the cadastre and in the registry of the municipality. Anyway, let's evaluate what we can do.</div><div><br></div><div>Thanks,</div><div>Best regards,</div><div><br></div><div>Lluís</div><div><div><span><div></div></span></div></div></body></html>