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<p>Does that preserve topology between buildings that share nodes?<br>
</p>
<div class="moz-signature">Nate Wessel<br>
<span style="font-size:10px;color:#777">Jack of all trades, Master
of Geography, PhD candidate in Urban Planning<br>
<a href="http://natewessel.com">NateWessel.com</a></span>
<br>
<br>
</div>
<div class="moz-cite-prefix">On 1/26/19 11:31 AM, James wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CANk4qi8sJuyYWcYq0oOJKxP5TGxqz8SO0M7JJo3MqXqL0aYk3w@mail.gmail.com">
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<div dir="auto">no need for scripts, qgis does this fine via the
Vector menu -> Geometry tools -> Simplify Geometries
utility. I simplified it to 20cm with the , but I think 40cm is
too aggressive.
<div dir="auto"><br>
</div>
<div dir="auto">I already have scripts to compile it into the
dataformat needed to be served.</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr">On Sat., Jan. 26, 2019, 11:16 a.m. Nate Wessel
<<a href="mailto:bike756@gmail.com" moz-do-not-send="true">bike756@gmail.com</a>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p>Hi all,</p>
<p>The wiki page is indeed looking a whole lot better right
now - my thanks and congrats to everyone who contributed!
There is a still a ways to go, but we seem to be getting
there quickly. <br>
</p>
<p>I'll echo John in saying that I would appreciate hearing
from some of the other people who chimed in to express
their doubts about the import. For my part, I'm not
satisfied yet - no surprise, I'm sure ;-). I'm thrilled
that we're talking and working together in the open, and
that addresses the biggest concern I had with the import.
<br>
</p>
<p>These are the big issues I see remaining: <br>
</p>
<p>1. <b>Validation</b>: Ideally I'd like to see a good
chunk (more than half) of the data that has been imported
already validated by another user before we proceed with
importing more data. Validation is part of the import
plan, so the import isn't done until validation is done
anyway. My hope is that this will flag any issues that we
can fix before moving forward, and give people time to
chime in on the import plan who maybe haven't already. I
don't want to see everything imported and only then do we
start systematically checking the quality of our work, if
ever. If no one wants to do it now, no one is going to
want to do it later either, and that doesn't bode well.<br>
</p>
<p>2. <b>Simplification</b>: James' analysis showed that
simplification could save several hundred megabytes (and
probably more) in Ontario alone. This is totally worth
doing, but we have to document the process and be very
careful not to lose valuable data. I believe there was
also a concern raised about orthogonal buildings being not
quite orthogonal - this is something that we should handle
at the same time, again, very carefully. We certainly
don't want to coerce every building into right angles.
With respect to James, I'm not sure this is something that
can be done with a few clicks in QGIS. I would be willing
to develop a script to handle this, but it would take me
about a week or two to find the time to do this properly.
We would need to simultaneously A) simplify straight lines
B) orthogonalize where possible and C) preserve topology
between connected buildings. This is not impossible, it
just takes time and care to do correctly.<br>
</p>
<p>3. <b>Speed and Size</b>: To John's point, it seems like
people certainly are not sticking to the areas they know,
unless they get around a whole hell of a lot more than I
do, and yes this is a problem. The whole Toronto region
was basically imported by two people: DannyMcD seems to
have done the entire west side of the region (hundreds of
square kilometers) while zzptichka imported the entire
east side of the region (again a truly massive area), both
in the matter of a week or two. They only stopped in the
middle where there were more buildings already and things
got a bit more difficult. The middle is where I live, and
when I saw that wave of buildings coming, I sounded the
alarms. <br>
This is way too fast - no one person should be able to
import the GTA in a couple weeks. A big part of the
problem, IMO is that the task squares are much too large,
and allow/require a user to import huge areas at once. At
the least, some of the task squares in central Toronto are
impossibly large, including hundreds or thousands of
buildings already mapped in OSM. Conflation on these, if
done properly would take the better part of a day, and
people are likely to get sloppy. <br>
I would like to see the task squares dramatically reduced
in size as a way of slowing people down, helping them
stick to areas they know well, and keeping them focused on
data quality over quantity. This would also make the
process much more accessible to local mappers who don't
already have tons of experience importing.<br>
</p>
<p>4. <b>Conflation</b>: I don't think the current
conflation plan is adequate(ly documented). In practice,
what people are actually doing may be fine, but I really
want to see some better thought on how to handle existing
buildings. Right now the wiki says for example "<i>Before
merging buildings data switch to OSM layer and see if
there are any clusters of buildings without any
meaningful tags you can delete to save time when merging</i>."<br>
With respect to whoever wrote this, this approach seems to
value time over data integrity and I just don't think
that's how OSM should operate. We need to be more careful
with the existing data, and we need to show that care with
clear and acceptable guidelines for handling the data that
countless people have already spent their time
contributing. We don't do OSM any favours by carelessly
deleting and replacing data. Help convince me that this
isn't what's happening.<br>
</p>
<p>Until some effort has been made to address these
concerns, I will continue to oppose this import moving
forward. And to be clear, I don't want to oppose this
import - I have too much else I should be focusing on. I
just don't want to see another shoddy import in Toronto
(or elsewhere). <br>
</p>
<p>Best,<br>
</p>
<div class="m_-501377306698867165moz-signature">Nate Wessel<br>
<span style="font-size:10px;color:#777">Jack of all
trades, Master of Geography, PhD candidate in Urban
Planning<br>
<a href="http://natewessel.com" target="_blank"
rel="noreferrer" moz-do-not-send="true">NateWessel.com</a></span>
<br>
<br>
</div>
<div class="m_-501377306698867165moz-cite-prefix">On 1/26/19
8:49 AM, john whelan wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div dir="ltr">
<div class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small">I'm
not certain how this addresses the concerns raised
by <span
style="font-family:Arial,Helvetica,sans-serif">Andrew
Lester and </span></div>
<table class="m_-501377306698867165gmail-ajC"
cellpadding="0">
<tbody>
<tr class="m_-501377306698867165gmail-UszGxc
m_-501377306698867165gmail-ajv">
<td colspan="2"
class="m_-501377306698867165gmail-gG"><span
class="m_-501377306698867165gmail-gI"></span><br>
</td>
<td colspan="2"
class="m_-501377306698867165gmail-gL"><span
class="m_-501377306698867165gmail-gI"><span
class="m_-501377306698867165gmail-qu"><span
name="Pierre Béland via Talk-ca"
class="m_-501377306698867165gmail-gD">Pierre
Béland<span class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small">,
</span></span></span></span></td>
</tr>
</tbody>
</table>
<span class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small">and
I seem to recall one other person who expressed
concerns.</span></div>
<div dir="ltr"><font face="verdana, sans-serif"><br>
</font></div>
<div dir="ltr"><font face="verdana, sans-serif"><span
class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small">I
think it is important that their concerns are
addressed.</span></font></div>
<div dir="ltr"><font face="verdana, sans-serif"><span
class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small"><br>
</span></font></div>
<div dir="ltr"><font face="verdana, sans-serif"><span
class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small">Perhaps
they would be kind enough to comment on whether or
not this approach addresses their concerns.</span></font></div>
<div dir="ltr"><font face="verdana, sans-serif"><br>
</font></div>
<div dir="ltr"><font face="verdana, sans-serif"><span
class="gmail_default">Do we have a concern that
some mappers have been importing buildings further
than say twenty kilometers from where they live?</span><br>
</font><br>
<div class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small"><br>
</div>
<div class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small">Have
you found volunteers of local mappers in </div>
<div class="gmail_default"
style="font-family:verdana,sans-serif;font-size:small">
<div class="gmail_default">Alberta</div>
<div class="gmail_default">British Columbia</div>
<div class="gmail_default">Manitoba</div>
<div class="gmail_default">New Brunswick</div>
<div class="gmail_default">Newfoundland and Labrador</div>
<div class="gmail_default">Northwest Territories</div>
<div class="gmail_default">Nova Scotia</div>
<div class="gmail_default">Nunavut</div>
<div class="gmail_default">Ontario</div>
<div class="gmail_default">Prince Edward Island</div>
<div class="gmail_default">Quebec</div>
<div class="gmail_default">Saskatchewan</div>
<div class="gmail_default">Yukon</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">Who will be willing to
oversee the import in each province?</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">Does this mean the
smaller provinces may not see any data?</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">How will you handle
cities of say 80,000 population in a smaller
province who have an interest in seeing their
buildings available but have no idea on how to
contact the provincial group?</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">If we go back to earlier
times it was a suggestion in talk-ca that we use
the single import approach and it was mentioned at
the time there didn't seem to be a list of local
mapper groups in Canada.</div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">I'm not saying the
approach of a single import as far as the import
list and talk-ca followed by a procedure of
locally organised mappers bringing in the data is
wrong I'm just trying to ensure the project moves
forward and we are in agreement. </div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">Thanks </div>
<div class="gmail_default"><br>
</div>
<div class="gmail_default">Cheerio John</div>
</div>
</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="m_-501377306698867165gmail_attr">On
Sat, 26 Jan 2019 at 00:17, OSM Volunteer stevea <<a
href="mailto:steveaOSM@softworkers.com"
target="_blank" rel="noreferrer"
moz-do-not-send="true">steveaOSM@softworkers.com</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">Thanks to some good
old-fashioned OSM collaboration, both the <a
href="https://wiki.osm.org/wiki/Canada_Building_Import"
rel="noreferrer noreferrer" target="_blank"
moz-do-not-send="true">https://wiki.osm.org/wiki/Canada_Building_Import</a>
and <a
href="https://wiki.osm.org/wiki/WikiProject_Canada/Building_Canada_2020#NEWS.2C_January_2019"
rel="noreferrer noreferrer" target="_blank"
moz-do-not-send="true">https://wiki.osm.org/wiki/WikiProject_Canada/Building_Canada_2020#NEWS.2C_January_2019</a>
have been updated. (The latter points to the former).<br>
<br>
In short, it says there are now step-by-steps to begin
an import for a particular province, and that as the
steps get fine-tuned (they look good, but might get
minor improvements), building a community of at least
one or two mappers in each of the provinces with data
available, the Tasking Manager can and will lift the
"On Hold" or "Stopped" status.<br>
<br>
Nice going, Canada!<br>
<br>
See you later,<br>
<br>
SteveA<br>
California<br>
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</blockquote>
</div>
<br>
<fieldset
class="m_-501377306698867165mimeAttachmentHeader"></fieldset>
<pre class="m_-501377306698867165moz-quote-pre">_______________________________________________
Talk-ca mailing list
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<a class="m_-501377306698867165moz-txt-link-freetext" href="https://lists.openstreetmap.org/listinfo/talk-ca" target="_blank" rel="noreferrer" moz-do-not-send="true">https://lists.openstreetmap.org/listinfo/talk-ca</a>
</pre>
</blockquote>
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rel="noreferrer" moz-do-not-send="true">Talk-ca@openstreetmap.org</a><br>
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rel="noreferrer noreferrer" target="_blank"
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</blockquote>
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</blockquote>
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