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<p class="gmail-western" style="margin-bottom:0cm">Emergency bays and bus
bays are physically very similar, i.e. a short piece of an additional
lane on a road.</p>
<p class="gmail-western" style="margin-bottom:0cm">Unfortunately the two
tags highway=emergency_bay and bus_bay=both|left|right use very
different approaches to describing essential the same physical
arrangement.
</p>
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<p class="gmail-western"><br>
</p>
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<p class="gmail-western" lang="it-IT">bus_bay=both|left|right</p>
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<p class="gmail-western" lang="it-IT">highway=emergency_bay</p>
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<p class="gmail-western" lang="it-IT">wiki page</p>
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<p class="gmail-western" lang="it-IT"><a href="https://wiki.openstreetmap.org/wiki/Key:bus_bay">https://wiki.openstreetmap.org/wiki/Key:bus_bay</a></p>
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<p class="gmail-western" lang="it-IT"><a href="http://wiki.openstreetmap.org/wiki/Tag:highway%3Demergency_bay">http://wiki.openstreetmap.org/wiki/Tag:highway%3Demergency_bay</a></p>
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<p class="gmail-western" lang="it-IT">node</p>
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<p class="gmail-western" lang="it-IT">no (according to the wiki
page)<br>yes (in reality there are few cases of bus_bay=yes with
highway=bus_stop)</p>
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<p class="gmail-western" lang="it-IT">yes</p>
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<p class="gmail-western" lang="it-IT">node example</p>
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<p class="gmail-western"><a href="http://www.openstreetmap.org/node/2134413721">http://www.openstreetmap.org/node/2134413721</a></p>
<p class="gmail-western"><a href="http://www.openstreetmap.org/node/1690562827">http://www.openstreetmap.org/node/1690562827</a></p>
<p class="gmail-western"><a href="http://www.openstreetmap.org/node/4892296128">http://www.openstreetmap.org/node/4892296128</a></p>
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<p class="gmail-western"><a href="http://www.openstreetmap.org/node/3246948212">http://www.openstreetmap.org/node/3246948212</a></p>
<p class="gmail-western"><br>
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<p class="gmail-western" lang="it-IT">way</p>
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<p class="gmail-western" lang="it-IT">yes</p>
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<p class="gmail-western" lang="it-IT">yes</p>
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<p class="gmail-western" lang="it-IT">way example</p>
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<p class="gmail-western" lang="it-IT"><a href="http://www.openstreetmap.org/way/253182588">http://www.openstreetmap.org/way/253182588</a></p>
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<p class="gmail-western" lang="it-IT"><a href="http://www.openstreetmap.org/way/460019134">http://www.openstreetmap.org/way/460019134</a></p>
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<p class="gmail-western" lang="it-IT">left|right|both</p>
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<p class="gmail-western" lang="it-IT">yes (mandatory)</p>
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<p class="gmail-western" lang="it-IT">not foreseen in the wiki page</p>
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<p class="gmail-western" lang="it-IT"><br>
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<p class="gmail-western" lang="it-IT">node: 55</p>
<p class="gmail-western" lang="it-IT">way: 1715</p>
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<p class="gmail-western" lang="it-IT">node: 3710</p>
<p class="gmail-western" lang="it-IT">way: 642</p>
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<p class="gmail-western" style="margin-bottom:0cm">I personally like the
bus_bay approach better, but I see the drawback of having to split
the road way twice for every occurrence, when you use the type:way
approach</p>
<p class="gmail-western" style="margin-bottom:0cm">The emergency_bay
approach is easier to map if you only consider the node approach and
only on one-way streets, assuming that you can define the
default as being on the right-hand side for right-hand-drive
countries (and symmetrically for the left-hand ones). For dual lane
traffic or for emergency bays on the "wrong" side of the
road you need an agreed way to define which side of the road. I do
not like the way approach of the emergency_bay tagging, as it
actually requires a separate way, which does not reflect the reality
on the ground.</p>
<p class="gmail-western" style="margin-bottom:0cm">As both tags are so far
relatively low-use, it may not be too late to unify the bus_bay and
emergency_bay mapping approaches.</p><p class="gmail-western" style="margin-bottom:0cm">Volker<br></p>
<div class="gmail_extra"><br><div class="gmail_quote"><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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