Hi maning,<br><br>What we and Ian do is to decompose the borders as a network of ways. Each boundary way should only be a dividing line between any two barangays (if known) and left unnamed and tagged with the lowest (numeric) possible admin_level. Then the borders surrounding a barangay are collected into a relation as are the ways surrounding a municipality, city, province, etc.<br>
<br>Example: City A is composed of barangays W, X, Y and Z.<br><br><font face="courier new,monospace"> ,--------,--------,<br> | 2 | 4 |<br></font><font face="courier new,monospace"> |1 W |3 |<br>
</font><font face="courier new,monospace"> | | X 5|<br> |--------| |<br> | 8 7| 6 |<br> | |--------|<br></font><font face="courier new,monospace"> |9 Y | |<br>
</font><font face="courier new,monospace"> | |11 Z 12|<br>
</font><font face="courier new,monospace"> | 10 | 13 |<br>
</font><font face="courier new,monospace"> '--------'--------'<br></font><br>Hopefully the ASCII art looks ok. In this example, we have a total of 13 ways all tagged with boundary=administrative. In addition, ways 1, 2, 4, 5, 12, 13, 10, and 9 are tagged with admin_level=6 (city) while the rest with admin_level=10 (barangay).<br>
<br>Then create relations for each of the barangays:<br><br>Barangay W:<br>type=boundary<br>boundary=administrative<br>admin_level=10<br>name=W<br>members: 1,2,3,8 (all as blank)<br><br>and so on.<br><br>Then finally, City A is another relation:<br>
type=boundary<br>boundary=administrative<br>admin_level=6<br>name=A<br>members: 1,2,4,5,12,13,10,9 (all as blank)<br><br>Hopefully this explains everything.<br><br>Eugene / seav<br><br><br><div class="gmail_quote">On Tue, May 26, 2009 at 6:36 PM, maning sambale <span dir="ltr"><<a href="mailto:emmanuel.sambale@gmail.com">emmanuel.sambale@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi,<br>
<br>
I am starting to add admin boundaries of Marikina (partly because I<br>
envy Makati!).<br>
<a href="http://www.openstreetmap.org/?lat=14.6442&lon=121.1174&zoom=14&layers=B000FTF" target="_blank">http://www.openstreetmap.org/?lat=14.6442&lon=121.1174&zoom=14&layers=B000FTF</a><br>
<br>
I am now adopting seav's proposal on the admin_levels and using<br>
relations for aggregating barangay boundaries into Marikina City<br>
borders.<br>
<br>
The admin boundaries around marikina (QC, pasig, san mateo, cainta and<br>
antipolo) maybe a bit messy right now. Partly because I am trying to<br>
understand how to merge marikina barangay boundaries into the existing<br>
boundaries (please don't touch them for the moment, I promise to<br>
finish this weekend).<br>
<br>
The hardest part is how to tag multiple boundary levels.<br>
<br>
for example, the northern border of Barangay Nangka:<br>
<a href="http://www.openstreetmap.org/browse/way/35024130" target="_blank">http://www.openstreetmap.org/browse/way/35024130</a><br>
admin_level = 10<br>
boundary = administrative<br>
name = Nangka<br>
<br>
is also the admin boundary of Marikina and San Mateo<br>
admin_level = 6<br>
<br>
which is also part of the Rizal border<br>
admin_level = 4<br>
<br>
which is also the regional boundary<br>
admin_level = 3<br>
<br>
Whew!<br>
<br>
When there are conflicts (in the OSM sense), I decided to treat higher<br>
admin level (i. e. barangay and municipalities), as a "priority" over<br>
other admin levels.<br>
Is this good practice?<br>
<br>
<br>
<br>
--<br>
cheers,<br>
maning<br>
------------------------------------------------------<br>
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</blockquote></div><br><br clear="all"><br>-- <br><a href="http://vaes9.codedgraphic.com">http://vaes9.codedgraphic.com</a><br>