<div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr">Hey Nate,<div>I've also looked into it and came across this paper: <a href="https://www.josis.org/index.php/josis/article/view/276/166">https://www.josis.org/index.php/josis/article/view/276/166</a></div><div>Sounds like what we need. </div><div>IMO this is the kind of stuff that needs to be dealt with in JOSM on a per-square basis rather than modifying original data. So you have control over the result and can possibly tweak it in the process if there are any issues. I've looked into plugins and found only "Building Generalization" plugin (<a href="https://wiki.openstreetmap.org/wiki/JOSM/Plugins/Building_Generalization">https://wiki.openstreetmap.org/wiki/JOSM/Plugins/Building_Generalization</a>) that is supposed to be able to fix this kind of problem. However, after running it on an area from Texas import with 90% of problematic buildings, it turns out to be doing pretty bad job: <a href="https://i.imgur.com/P5mbjRf.jpg">https://i.imgur.com/P5mbjRf.jpg</a></div><div><br></div><div><br></div><div><br></div></div></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Jan 28, 2019 at 10:08 AM Nate Wessel <<a href="mailto:bike756@gmail.com">bike756@gmail.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">
<div bgcolor="#FFFFFF">
<p>Hi all, <br>
</p>
<p>I was reading about orthogonalization yesterday and came across
this paper...<br>
<br>
<a class="gmail-m_-6643986553955640843moz-txt-link-freetext" href="https://icaci.org/files/documents/ICC_proceedings/ICC2009/html/refer/19_2.pdf" target="_blank">https://icaci.org/files/documents/ICC_proceedings/ICC2009/html/refer/19_2.pdf</a><br>
<br>
...which describes an algorithm that seems to quite effectively
disregard angles that are not close to orthogonal while
straightening those that are. I added a link to it in the wiki.
This may not be implemented in JOSM, but there's no reason we
couldn't pre-process the data in this way.<br>
</p>
<p>From Pierre's analysis, it sounds to me like we really do need to
consider orthogonalizing buildings where possible, which should be
pretty much all buildings (I could see some buildings sharing
nodes getting complicated). Once the angles are corrected, I
imagine we should be able to simplify with a very small threshold
and get good results. <br>
</p>
<p>Given the number of buildings in this import, this is absolutely
something worth doing. Four million buildings times one tiny
problem equals one really huge problem. Let's fix it now while
it's still relatively easy. <br>
</p>
<p>Best,<br>
</p>
<div class="gmail-m_-6643986553955640843moz-signature">Nate Wessel<br>
<span style="font-size:10px;color:rgb(119,119,119)">Jack of all trades, Master
of Geography, PhD candidate in Urban Planning<br>
<a href="http://natewessel.com" target="_blank">NateWessel.com</a></span>
<br>
<br>
</div>
<div class="gmail-m_-6643986553955640843moz-cite-prefix">On 1/28/19 9:17 AM, john whelan wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_default" style="font-family:verdana,sans-serif;font-size:small">Interesting,
although I'm not sure what the best approach is. </div>
<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">31
Hamilton is interesting. If you look at the buildings next to
it they don't have house numbers. Look at the history and
you'll see it was first created in 2010 with potlatch and
edited once more in 2011.</div>
<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">At my
first glance at Kingston the small deviations form 90 degrees
did not stand out. </div>
<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">I think
we can reasonably expect Microsoft to create a Canadian
buildings file and you seem to be comfortable that the ones it
has in the US are of a reasonable standard.</div>
<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">Part of
my background is large databases and my personal view is the
minimum data needed the faster the system runs and less data
needs to get flipped round and backed up.</div>
<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">Could
you run the analysis over Ottawa?</div>
<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">Looking
closely at a few in Ottawa I note that there are some bay
windows and other small features I might not have bothered
with if mapping with JOSM with the buildings_tool. Because of
a few 45 degree angles involved this isn't something that can
be easily solved.</div>
<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">Ottawa
I think at some level can be considered a reasonable success.
Certainly we added a lot of extra information to the building
outlines.</div>
<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">I think
the trade off is using the municipal data gives us the
buildings with perhaps more detail than I might like but many
would like to see the buildings imported.</div>
<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">Dunno
(Do not know for translate tools.)</div>
<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">What is
the ideal building outline in OpenStreetMap?</div>
<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">What is
an acceptable building outline in OpenStreetMap? <br>
</div>
<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">Suggestions</div>
<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">Thanks</div>
<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">Cheerio
John</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail-m_-6643986553955640843gmail_attr">On Sun, 27 Jan 2019 at 23:28,
Pierre Béland <<a href="mailto:pierzenh@yahoo.fr" target="_blank">pierzenh@yahoo.fr</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">
<div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydpc239e021yahoo-style-wrap" style="font-family:verdana,helvetica,sans-serif;font-size:13px">
<div id="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydpc239e021yiv7713919613">
<div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydpc239e021yiv7713919613ydpab95b09ayahoo-style-wrap" style="font-family:verdana,helvetica,sans-serif;font-size:13px">
<div>
<div>Bonjour John</div>
<div><br>
</div>
<div>La géométrie des bâtiments est un sujet qui
préoccupe plusieurs contributeurs en particulier
pour les imports de données. Dans un tel cas, il
est difficile de revenir en arrière et il est
préférable de bien planifier, analyser. Comme
on le voit avec l'import en Ontario, on observe
qu'il est possible de s'assurer que les données
soient orthogonales et que les noeuds inutiles
soient éliminées.</div>
<div><br>
</div>
<div>En comparaision les données Microsoft
importées à Arlington, au Texas présentent des
géométries plus standard. À première vue, les
ratios de géométrie irrégulières semblent
beaucoup plus bas. <br>
</div>
<div><br>
</div>
<div>Une nouvelle analyse pour l'Ontario, cette
fois-ci pour les données importées dans la zone
Oshawa-Hamilton montre 62% sont des polygones
avec des formes irrégulières.</div>
<br clear="none">
<div>A noter que pour déterminer les polygones
réguliers, j'utilise un spectre de degrés assez
large <br clear="none">
</div>
<div>- lignes droites entre 178 et 182 degrés<br clear="none">
</div>
<div>- angles droits entre 88 et 92 degrés, entre
268 et 272<br clear="none">
</div>
<div>- autres types de polygones : variation de
+-2.2% vs angle moyen pour le polygone
(octogones, hexagones, etc)</div>
<div><br>
</div>
<div>Dans les analyses de géométrie, un grand
nombre de polygones classés FB_oo ont des
géométries où on retrouve des batiments presque
orthogonaux mais avec un ou des angles entre 86
et 94 degrés. Cela veut sans doute représenter
des angles droits mais l'écart est assez grand.
Dois-t-on se satisfaire de cela?</div>
<div> <br clear="none">
</div>
<div>En ce qui a trait aux normes de qualité, elle
sont généralement implicites et guidées par les
outils disponiibles. Avec JOSM, on s'attend
généralement qu'un contributeur utilisera le
greffon Building et saura tracer des batiments
rectangulaires et si nécessaire superposer
plusieurs formes rectangulaires légérement
décalées et les joindre en un seul polygone.
Les contributeurs devraient normalement aussi
maitriser les notions de perspective lorsque
l'image est prise avec un certain angle par
rapport à la verticale. Les outils
d'intelligence artificielle aussi ?<br>
</div>
<br clear="none">
<div>Selon toi, quelles règles devrait-on
appliquer pour évaluer la géométrie des
bâtiments ?</div>
<div><br clear="none">
</div>
<div>L'exemple de géométrie que tu as présenté, on
le retrouve effectivement beaucoup dans les
imports pour l'Ontario. Ce bâtiment n'est pas
dans mon fichier par ce que le contributeur
n'était pas répertorié dans le projet <a shape="rect" href="http://tasks.osmcanada.ca/project/145" rel="nofollow" target="_blank">http://tasks.osmcanada.ca/project/145</a>.
Je n'ai retenu que les contributeurs qui y
apparaissait.</div>
<div><br clear="none">
</div>
Pour des exemples similaires contenus dans le
fichier d'analyse, regardes près du 31 Hamilton
street.
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydpc239e021yiv7713919613ydpab95b09asignature"><a shape="rect" href="https://www.openstreetmap.org/#map=20/44.23749975223997/-76.49539748034509" rel="nofollow" target="_blank">https://www.openstreetmap.org/#map=20/44.23749975223997/-76.49539748034509</a>
<div><span></span>
<div><br clear="none">
</div>
<div><span>Ce polygone contient 22 angles, des
quasi lignes droites (symbole ir), et des
quasi 90 degrés (oo) et des angles
irréguliers tles 98,8, 94,3<br clear="none">
</span></div>
<div><span>Est-ce un polygone irrégulier ou un
effet de perspective? Comment le
représenter?<br clear="none">
</span></div>
</div>
<div><span></span><span>"59879471" "22"
"FB_irreg"
"{o,o,o,o,ir,ir,ir,ir,oo,o,o,oo,oo,ir,oo,o,oo,rr,ir,ir,o,o}"
"{90.6,90.7,89.3,89.2,95.4,94.8,178,83.2,86.1,90.9,89.2,94,93.6,94.3,93.1,89.9,93.8,171.2,98.8,94.3,90.9,89.9}"<br clear="none">
</span>
<div><span><br clear="none">
</span></div>
<div><span>Angle 177,6 presque droit, noeud
inutile - normalement un simple rectangle<br clear="none">
</span></div>
<div><span>"657790097" "5" "FB_irreg"
"{o,o,ir,o,o}" "{90,91,177.6,91.4,90}"</span></div>
<div><span style="font-style:italic;color:rgb(0,0,191);font-weight:bold"> </span></div>
<div><span style="font-style:italic;color:rgb(0,0,191);font-weight:bold"></span><span></span>
<div><br clear="none">
</div>
<div>Un peu d'humour la-dessus. Un robot
trace un rectangle parfait. Un premier
contributeur le voit et dit cela ne semble
pas normal et y ajoute un peu de
distorsion. Un deuxième décide d'y ajouter
un point et d'étirer le tout. Si on
poursuit le dessin dans ce sens, cela
finira par ressembler à un clown!</div>
<br clear="none">
</div>
<div><br clear="none">
</div>
<div><br clear="none">
</div>
</div>
<span style="font-style:italic;color:rgb(0,0,191);font-weight:bold"><font face="garamond, new york, times, serif">Pierre
</font><br clear="none">
</span></div>
</div>
<div><br clear="none">
</div>
<div><br clear="none">
</div>
</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydpc239e021yiv7713919613ydp782cde0ayahoo_quoted" id="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydpc239e021yiv7713919613ydp782cde0ayahoo_quoted_9540384810">
<div>
</div>
</div>
</div>
</div>
</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613yqt4382069100" id="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613yqtfd92784">
<div> Le dimanche 27 janvier 2019 09 h 51 min 10 s HNE,
john whelan <<a href="mailto:jwhelan0112@gmail.com" target="_blank">jwhelan0112@gmail.com</a>>
a écrit : </div>
<div><br clear="none">
</div>
<div><br clear="none">
</div>
<div>
<div id="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703">
<div>
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703gmail_default" style="font-family:verdana,sans-serif;font-size:small">If you take a
look at 942 Bridle Path Crescent for example
whilst it isn't exactly square the
deviations from 90 degrees to me are
relatively minor. I assume that this is the
sort of thing you are talking about?<br clear="none">
</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703gmail_default" style="font-family:verdana,sans-serif;font-size:small"><br clear="none">
</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703gmail_default" style="font-family:verdana,sans-serif;font-size:small"><a shape="rect" href="https://www.openstreetmap.org/search?query=942%20Bridle%20Path%20Crescent%20kingston#map=19/44.25311/-76.59308" rel="nofollow" target="_blank">https://www.openstreetmap.org/search?query=942%20Bridle%20Path%20Crescent%20kingston#map=19/44.25311/-76.59308</a></div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703gmail_default" style="font-family:verdana,sans-serif;font-size:small"><br clear="none">
</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703gmail_default" style="font-family:verdana,sans-serif;font-size:small">Are we expecting
too high a standard?</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703gmail_default" style="font-family:verdana,sans-serif;font-size:small"><br clear="none">
</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613ydp782cde0ayiv3839781703gmail_default" style="font-family:verdana,sans-serif;font-size:small">Cheerio John<br clear="none">
</div>
</div>
</div>
</div>
<br clear="none">
</div>
</div>
</div>
</div>
<div class="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613yqt4382069100" id="gmail-m_-6643986553955640843gmail-m_5269169313036325482ydp842d0bd5yiv7713919613yqtfd02950"> </div>
</div>
</blockquote>
</div>
</blockquote>
</div>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr">Best Regards,<br> Yaro Shkvorets</div></div>