<div dir="ltr">I added the no u-turns you've linked, and likely the ones you've removed.<div><div>Honestly, I hadn't read the turn restriction wiki page as I'd only ever done them within iD.</div></div><div><br></div><div>I think you've missed a more important section from the introduction of the wiki page:</div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Don't map turn restrictions that are the default for a given jurisdiction and are not signed.<br></blockquote><div><br></div><div>So I'm okay with not adding the defaults, and I'll endeavour to clean up the unnecessary restrictions which I have added.</div><div><br></div><div>The only thing I'm a bit puzzled about is u-turns at intersections with/without islands, such as <a href="https://www.openstreetmap.org/#map=19/-43.55042/172.63678">https://www.openstreetmap.org/#map=19/-43.55042/172.63678</a> (just north of your original links). Technically, you're allowed to perform a u-turn at any intersection as long as there's an island, and as long as there's no no-u-turn sign
(such as Milton Street heading east).</div><div>Unfortunately, there's no differentiation between the roads to indicate that it's separated by an island, and there's no "u-turn allowed" tag (which would break the "don't add defaults" rule in this case anyway), so routers would incorrectly assume the u-turn is not allowed.</div><div>Is the preferred approach here to split the road at the island?</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, 4 Aug 2020 at 10:38, Eliot Blennerhassett <<a href="mailto:eliot@blennerhassett.gen.nz">eliot@blennerhassett.gen.nz</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Now I've seen these restrictions visualizers...<br>
<br>
<a href="https://ahorn.lima-city.de/tr/?zoom=18&lat=-43.553894&lon=172.635211&layer=Grayscale&overlays=TTT" rel="noreferrer" target="_blank">https://ahorn.lima-city.de/tr/?zoom=18&lat=-43.553894&lon=172.635211&layer=Grayscale&overlays=TTT</a><br>
<br>
<a href="https://restrictions.morbz.de/#17/-43.55386/172.63474" rel="noreferrer" target="_blank">https://restrictions.morbz.de/#17/-43.55386/172.63474</a><br>
<br>
I'm seeing a huge proliferation of labelling every way of a junction<br>
with what I call a "Self No U-turn" i.e. the from and to members are the<br>
same segment.<br>
<br>
See for example this area:<br>
<br>
<a href="https://ahorn.lima-city.de/tr/?zoom=18&lat=-43.553894&lon=172.635211&layer=Grayscale&overlays=TTT" rel="noreferrer" target="_blank">https://ahorn.lima-city.de/tr/?zoom=18&lat=-43.553894&lon=172.635211&layer=Grayscale&overlays=TTT</a><br>
<br>
<a href="https://restrictions.morbz.de/#17/-43.55386/172.63474" rel="noreferrer" target="_blank">https://restrictions.morbz.de/#17/-43.55386/172.63474</a><br>
<br>
If you look at<br>
<a href="https://wiki.openstreetmap.org/wiki/Relation:restriction#Tags" rel="noreferrer" target="_blank">https://wiki.openstreetmap.org/wiki/Relation:restriction#Tags</a>, it says<br>
"*to add a no_u_turn restriction relation seems only useful if<br>
from-member and to-member are different way objects"<br>
<br>
So I think all these no-U that I'm seeing are useless, and in some cases<br>
actually erroneous e.g. when the T junction is between a driveway and a<br>
road it is not prohibited to do a U turn on the road. And they make it<br>
harder to review actual turn restrictions.<br>
<br>
<br>
I've deleted a bunch, but I'm interested if anyone else has any opinion<br>
on this.<br>
<br>
<br>
No-U-turn where the From and To members are different ways is of course<br>
still valid e.g.<br>
<a href="https://www.openstreetmap.org/relation/9027919" rel="noreferrer" target="_blank">https://www.openstreetmap.org/relation/9027919</a><br>
<a href="https://www.openstreetmap.org/relation/5391722" rel="noreferrer" target="_blank">https://www.openstreetmap.org/relation/5391722</a><br>
<br>
--<br>
Eliot<br>
<br>
<br>
<br>
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</blockquote></div>