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--></style></head><body lang=EN-GB link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Jem,</p><p class=MsoNormal>you have, of course, fixed the issue already. That was the right ting to do. Though, there are many, many similar cases and not only in natural=water tagged geometries. Many users run a geometry-model based recognition program that detects and repairs these problems even not knowing they were there. </p><p class=MsoNormal>However, two comments from the last mail deserve some further comments.</p><p class=MsoNormal><span lang=NO-BOK>>> </span>Relations should not be used to collect thing together.<o:p></o:p></p><p class=MsoNormal><span lang=NO-BOK>>></span>? That is what they can be used for. See the site relation as an example.<o:p></o:p></p><div><div><p class=MsoNormal>Yes, “they can be used for” but here OSM wiki is explicit “should not be used” (obligatory restriction). Besides, when I see/search the OSM wiki using the “site relation” key I got this <a href="https://wiki.openstreetmap.org/wiki/Relations/Proposed/Site"><span style='color:windowtext;text-decoration:none'>https://wiki.openstreetmap.org/wiki/Relations/Proposed/Site</span></a>. It is a proposal just like many other “collecting thing together” proposals like multiobject, group, cluster... Using these proposals in private database versions is up to the users but should not be used in OSM data source. Otherwise, <span lang=NO-BOK>mappers </span>can cause damage to others<span lang=NO-BOK>, </span>serious professional mismatch and huge data and work redundancy. Just look at this <a href="https://osm.org/go/cAO2c--?relation=1124369"><span style='color:windowtext;text-decoration:none'>https://osm.org/go/cAO2c--?relation=1124369</span></a>. Why, just for the Wikipedia link or some never used names?</p><p class=MsoNormal>>> MP relations should be restricted to the areas which have inners:...<o:p></o:p></p><p class=MsoNormal>>> No. They can be used to collect a series of outer ways to form the boundary of a feature e.g. an administration boundary usually shares ways with adjacent</p></div><p class=MsoNormal>>>administrations</p><p class=MsoNormal>Irrelevant contrast. However, the second line perfectly illustrates how to present an administrative (political) AREA feature using MP. Because of many rendering issues related to overlapping areas, if only the area boundary is needed, OSM wiki has introduced the “boundary” as a new tagging key and using MP declared deprecated for that purpose. The suggestion in the first line is not acceptable for now. Simply, we don’t have other tools to represent areas with just one border line when the number of border nodes (considerably) exceeds the node number limit in the “way”.</p></div><p class=MsoNormal>Sandor</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Sent from <a href="https://go.microsoft.com/fwlink/?LinkId=550986">Mail</a> for Windows 10</p><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='border:none;padding:0cm'><b>From: </b><a href="mailto:61sundowner@gmail.com">Warin</a><br><b>Sent: </b>21 September 2018 01:33<br><b>To: </b><a href="mailto:talk@openstreetmap.org">talk@openstreetmap.org</a><br><b>Subject: </b>Re: [OSM-talk] Waterway rel with mix of line & poly</p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>On 21/09/18 06:11, Jem wrote:<o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>Thank you both. That's very helpful.<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Thu, 20 Sep 2018 at 22:25, Dave F <<a href="mailto:davefoxfac63@btinternet.com">davefoxfac63@btinternet.com</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><p class=MsoNormal style='margin-left:204.0pt'>Hi<br><br>Short answer: Yes<br><br>There's a few problems here:<br><br>Relations should not be used to collect thing together.<o:p></o:p></p></div></blockquote></div></blockquote><p class=MsoNormal>? That is what they can be used for. See the site relation as an example. <br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><p class=MsoNormal style='margin-left:204.0pt'>There shouldn't be tags on the ways which conflict with those in the relations<o:p></o:p></p></div></blockquote></div></blockquote><p class=MsoNormal>True.<br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><p class=MsoNormal style='margin-left:204.0pt'>MP relations require a 'type' tags and 'inners' & 'outers' roles<o:p></o:p></p></div></blockquote></div></blockquote><p class=MsoNormal>True<br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><p class=MsoNormal style='margin-left:204.0pt'>In this case the Southern section shouldn't be a polygon <o:p></o:p></p></div></blockquote></div></blockquote><p class=MsoNormal>Did not look.<br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><p class=MsoNormal style='margin-left:204.0pt'>MP relations should be restricted to the areas which have inners: <a href="https://www.openstreetmap.org/relation/2571440#map=19/51.15275/-2.05045" target="_blank">https://www.openstreetmap.org/relation/2571440#map=19/51.15275/-2.05045</a><o:p></o:p></p></div></blockquote></div></blockquote><p class=MsoNormal style='margin-bottom:12.0pt'>No. They can be used to collect a series of outer ways to form the boundary of a feature e.g. an administration boundary usually shares ways with adjacent administrations. <o:p></o:p></p><p class=MsoNormal><span style='color:black'><o:p> </o:p></span></p></div></body></html>