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<div class="moz-cite-prefix">Hi,<br>
<br>
I left this unsent for some time, so it may duplicate what has
already been said.<br>
But it's uttermost important.<br>
<br>
On 2014-02-05 07:44, Kytömaa Lauri wrote :<br>
</div>
<blockquote
cite="mid:D312F9ED2DBBD8479518C8D52CD1697301502C124A@EXMDB04.org.aalto.fi"
type="cite">
<pre wrap="">
Bryce Nesbitt wrote:
</pre>
<blockquote type="cite">
<pre wrap="">does not represent what's on the ground: there won't be a "one way street" sign.
</pre>
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<pre wrap="">
Dual carriage roads don't have one way signs, either, but the parts have oneway=yes. </pre>
</blockquote>
They don't have signs because the rule is implicit: it's stated in
traffic rules that dual carriage roads are dual one-way (it's
obvious too). BUT routing (GPS) software is not (well) aware of
dual carriage ways and so we must tell them the one-way explicitly.<br>
<blockquote
cite="mid:D312F9ED2DBBD8479518C8D52CD1697301502C124A@EXMDB04.org.aalto.fi"
type="cite">
<pre wrap="">I just noticed that the relatively recently changed description on the Key:oneway wiki page is even wrong because it tries to set the requirement of a oneway street sign.
It's the effect "traffic on this way may flow in one direction only", not the signs, that are more relevant to most use cases.</pre>
</blockquote>
Indeed. And signs are probably irrelevant in all cases. The biggest
problem is having to FUZZILY say "probably".<br>
GPS routing software is a number one OSM application. It follows
strict logical rules to use well defined tags and if we don't use <b>the
same</b>, <b>strict</b> logic and the same tags, it won't
understand and will send cars the wrong way. It doesn't look at
traffic signs and, as a general remark, being inventive misses the
point. The remark I once read "[no need to tag it precisely,]
everybody knows" does not apply here. What is obvious for humans is
not to GPS software.<br>
<br>
There doesn't seem to be routing quality assurance tools, not even
Osmose detecting detectable mistakes, and I've corrected quite a
number of bad tagging mistakes that I found with Osmand.<br>
Many people appear confused with the restriction rules.<br>
There should be a wiki page listing exactly what tags mappers and
routers must use.<br>
There should be <a href="http://www.yournavigation.org/index.php">a
tool like this</a> implementing exactly those rules and using an
up to date map, at least daily or almost life (for example on demand
according to the requests) so that mappers can check their doings on
short distances.<br>
AFAICS, OSM routing is not reliable. It does make useful routes on
the large scale but it makes many errors when coming down to the
details and one may be booked for trusting it too much.<br>
<br>
Cheers,<br>
<br>
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<td>André.</td>
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<br>
<br>
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