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</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I tought it was obvious, but let me spell it out: such restrictions represent a default which we should be recorded somewhere (not necessary inside OSM) once and observed by data consumers, not by creating potentially 100000’s of relations to again and again encode the default behaviour.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>This is exactly the problem that exists in Brazil, where u-turns back onto the same way at intersections are generally prohibited without any explicit sign allowing them, so some mappers add 4 no_u_turn at every single intersection node.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Please refer to: <a href="https://github.com/openstreetmap/iD/issues/2527">https://github.com/openstreetmap/iD/issues/2527</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>In fact, it is also reapet, IN BOLD, on the main relation:restriction page: https://wiki.openstreetmap.org/wiki/Relation:restriction<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:1.2pt;margin-left:19.2pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1;background:white'><![if !supportLists]><span style='font-size:10.0pt;font-family:Symbol;color:#222222'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><b><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222'>Don't map </span></b><span style='font-size:10.5pt;font-family:"Arial",sans-serif;color:#222222'>turn restrictions that are <b>the default</b> for a given jurisdiction <b>and</b> are <b>not signed</b>. It is much better to ensure that routing engines embody the regional rule rather than mapping every occurrence as a turn restriction. This applies particularly to unsigned U-turns in Brazil, where using turn restrictions will require hundreds or thousands of restrictions and micro-segmentation of all roads which in turn make editing data hard.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Cheers,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Thorsten<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Paul Johnson <baloo@ursamundi.org> <br><b>Sent:</b> Friday, 6 April 2018 07:50<br><b>To:</b> Tag discussion, strategy and related tools <tagging@openstreetmap.org><br><b>Subject:</b> Re: [Tagging] no_u_turn restrictions for every entry/exit into a roundabout when the way is split because of physical separation?<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Rather than mindlessly barfing back "But the wiki says…", how about a critical argument? Best practices aren't set in stone and necessarily should evolve as better approaches become apparent.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>In many jurisdictions (esp in North America), such rules are quite readily available and under government copyright online already. It's no less verifiable than ground truth, and just as applicable to navigation.<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Thu, Apr 5, 2018, 16:34 <<a href="mailto:osm.tagging@thorsten.engler.id.au">osm.tagging@thorsten.engler.id.au</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-right:0cm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="https://wiki.openstreetmap.org/wiki/Good_practice#Don.27t_map_your_local_legislation.2C_if_not_bound_to_objects_in_reality" target="_blank">https://wiki.openstreetmap.org/wiki/Good_practice#Don.27t_map_your_local_legislation.2C_if_not_bound_to_objects_in_reality</a></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Paul Johnson <<a href="mailto:baloo@ursamundi.org" target="_blank">baloo@ursamundi.org</a>> <br><b>Sent:</b> Thursday, 5 April 2018 23:38<br><b>To:</b> Tag discussion, strategy and related tools <<a href="mailto:tagging@openstreetmap.org" target="_blank">tagging@openstreetmap.org</a>><br><b>Subject:</b> Re: [Tagging] no_u_turn restrictions for every entry/exit into a roundabout when the way is split because of physical separation?</span><o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>I don't think that's particularly harmful. I'm not against extending the criteria to published laws, particularly when those laws are documented in an official source.<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On Wed, Apr 4, 2018, 23:10 <<a href="mailto:osm.tagging@thorsten.engler.id.au" target="_blank">osm.tagging@thorsten.engler.id.au</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><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Actually, it’s not just relatively harmless “noise”. Because such no_u_turn restrictions are indistinguishable from e.g. this one: <a href="https://www.openstreetmap.org/relation/8182004" target="_blank">https://www.openstreetmap.org/relation/8182004</a> (which I just created), that actually has a sign “on the ground”: <a href="https://www.google.com.au/maps/@-27.2141567,153.0014115,3a,75y,100.42h,82.68t/data=!3m6!1e1!3m4!1s-vnw60jwbq7XyR_-zZfreg!2e0!7i13312!8i6656" target="_blank">https://www.google.com.au/maps/@-27.2141567,153.0014115,3a,75y,100.42h,82.68t/data=!3m6!1e1!3m4!1s-vnw60jwbq7XyR_-zZfreg!2e0!7i13312!8i6656</a> (excuse the streetview link, don’t have another photo of it right now, but I’m driving past it almost every day and am well aware of it).</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Tod Fitch <<a href="mailto:tod@fitchdesign.com" target="_blank">tod@fitchdesign.com</a>> <br><b>Sent:</b> Thursday, 5 April 2018 09:50<br><b>To:</b> Tag discussion, strategy and related tools <<a href="mailto:tagging@openstreetmap.org" target="_blank">tagging@openstreetmap.org</a>><br><b>Subject:</b> Re: [Tagging] no_u_turn restrictions for every entry/exit into a roundabout when the way is split because of physical separation?</span><o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Seems like tagging “noise” to me. I’d expect a router to use the roundabout itself because exiting, making a U turn and then re-entering the roundabout will be longer and thus slower. Since the no U turn relations are there to make routing work and a reasonable router won’t need them, I’d say they are “noise”. If I were to go in to fix something on that intersection, I’d probably remove the no U turn restriction(s). But I don’t think I’d go out of my way to find them.<o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Cheers!<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On Apr 4, 2018, at 4:36 PM, <a href="mailto:osm.tagging@thorsten.engler.id.au" target="_blank">osm.tagging@thorsten.engler.id.au</a> wrote:<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I’ve noticed that someone from the Microsoft Open Map team is very busy adding turn restrictions all over the place (<span class=m-4887133605491206971m4715304138645199996apple-converted-space> </span><a href="https://www.openstreetmap.org/user/shawat94/" target="_blank"><span style='color:#954F72'>https://www.openstreetmap.org/user/shawat94/</span></a><span class=m-4887133605491206971m4715304138645199996apple-converted-space> </span>).</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>In my local neighbourhood, I noticed that he added no_u_turn restrictions to all the nodes where a road into in/out of a roundabout is splitting (because of physical separation). Which basically amounts to 4 no_u_turn restrictions for every single roundabout.</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>e.g. here:</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="https://www.openstreetmap.org/changeset/57747093" target="_blank"><span style='color:#954F72'>https://www.openstreetmap.org/changeset/57747093</span></a></span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><a href="https://www.openstreetmap.org/changeset/57674063" target="_blank"><span style='color:#954F72'>https://www.openstreetmap.org/changeset/57674063</span></a></span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>There is no actual no_u_turn sign in any of these locations, it’s just (mostly) physically a bad idea to attempt a u-turn here.</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Just a few weeks ago I discussed exactly this in #osm and the conclusion was that it was neither necessary nor desirable to do this.</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I made a comment about that to the first of the two changesets linked above, but haven’t gotten a reply.</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>So, what is the general opinion about this here? Should these turn restrictions be created or not?</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Cheers,</span><o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Thorsten</span><o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:10.5pt;font-family:"Helvetica",sans-serif'>_______________________________________________<br>Tagging mailing list<br></span><a href="mailto:Tagging@openstreetmap.org" target="_blank"><span style='font-size:10.5pt;font-family:"Helvetica",sans-serif;color:#954F72'>Tagging@openstreetmap.org</span></a><span style='font-size:10.5pt;font-family:"Helvetica",sans-serif'><br></span><a href="https://lists.openstreetmap.org/listinfo/tagging" target="_blank"><span style='font-size:10.5pt;font-family:"Helvetica",sans-serif;color:#954F72'>https://lists.openstreetmap.org/listinfo/tagging</span></a><o:p></o:p></p></div></blockquote></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>_______________________________________________<br>Tagging mailing list<br><a href="mailto:Tagging@openstreetmap.org" target="_blank">Tagging@openstreetmap.org</a><br><a href="https://lists.openstreetmap.org/listinfo/tagging" target="_blank">https://lists.openstreetmap.org/listinfo/tagging</a><o:p></o:p></p></blockquote></div></div></div></div></div></div><p class=MsoNormal>_______________________________________________<br>Tagging mailing list<br><a href="mailto:Tagging@openstreetmap.org" target="_blank">Tagging@openstreetmap.org</a><br><a href="https://lists.openstreetmap.org/listinfo/tagging" target="_blank">https://lists.openstreetmap.org/listinfo/tagging</a><o:p></o:p></p></blockquote></div></div></div></body></html>