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<DIV>----- Original Message ----- </DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=artem@mapnik.org href="mailto:artem@mapnik.org">Artem Pavlenko</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=reviews@pacific-rim.net
href="mailto:reviews@pacific-rim.net">David Groom</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Cc:</B> <A title=talk@openstreetmap.org
href="mailto:talk@openstreetmap.org">talk@openstreetmap.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, March 23, 2007 1:48
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [OSM-talk] Slippy map -
Mapnik layer UK coastlines</DIV>
<DIV><BR></DIV>Hi David,
<DIV><BR>
<DIV>
<DIV>On 23 Mar 2007, at 11:48, David Groom wrote:</DIV><BR
class=Apple-interchange-newline>
<BLOCKQUOTE type="cite">
<DIV style="MARGIN: 0px">It seems that the UK coastline is beginning to
render better in the Mapnik<SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px">layer of the slippy map (it's a solid blue fill,
rather than the odd shaped<SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px">grey polygons).</DIV></BLOCKQUOTE>
<BLOCKQUOTE type="cite">
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV>
<DIV style="MARGIN: 0px">However it does appear that the source for the
coastline might be a rather<SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px">out of date planet file.</DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV>
<DIV style="MARGIN: 0px">In some places, eg<SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px"><A
href="http://www.openstreetmap.org/index.html?lat=50.85383936185782&lon=-1.315713476905844&zoom=15">http://www.openstreetmap.org/index.html?lat=50.85383936185782&lon=-1.315713476905844&zoom=15</A><SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px">,there is an exact correlation between coastline
which is shown in the<SPAN class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px">Mapnik and Osmarender layers.</DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV>
<DIV style="MARGIN: 0px">In other places eg ,<SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px"><A
href="http://www.openstreetmap.org/index.html?lat=50.81094579389664&lon=-0.09869895092239864&zoom=15">http://www.openstreetmap.org/index.html?lat=50.81094579389664&lon=-0.09869895092239864&zoom=15</A><SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px">,the coastline outline in the Osmarender layer
seems to be much more recent<SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MARGIN: 0px">than the Mapnik layer.</DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV></BLOCKQUOTE>
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV>For most of the world I was using original shoreline data, hence it's not
as smooth as it should. Polygons are only available for England and Wales, the
rest gets blue shoreline lines. To have proper polygons for the
whole planet :</DIV>
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV>1. We need to agree that storing countries boundaries as polygons is way
forward.</DIV>
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV>2. We have to decide if storing these polygons in main OSM database is a
good idea or not. I personally think it'll be better to store them
separately. </DIV>
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV>3. Start creating polygons. I have all the tools and I'm happy to help
anyone, but it is a big task which requires community participation.</DIV>
<DIV> On the other hand, If one person capable of fixing most of the UK
coastline it should be peanuts for OSM as a whole. If you want to see nice
blue sea and land just do it, don't wait!</DIV>
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV> Cheers,</DIV>
<DIV>Artem</DIV><BR>
<BLOCKQUOTE type="cite">
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"></DIV>
<DIV style="MARGIN: 0px">David<SPAN
class=Apple-converted-space> </SPAN></DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV>
<DIV
style="MARGIN: 0px">_______________________________________________</DIV>
<DIV style="MARGIN: 0px">talk mailing list</DIV>
<DIV style="MARGIN: 0px"><A
href="mailto:talk@openstreetmap.org">talk@openstreetmap.org</A></DIV>
<DIV style="MARGIN: 0px"><A
href="http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk">http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk</A></DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV></BLOCKQUOTE></DIV><BR>
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<DIV>Artem Pavlenko</DIV>
<DIV><A href="http://mapnik.org">http://mapnik.org</A></DIV>
<DIV><BR class=khtml-block-placeholder></DIV><BR
class=Apple-interchange-newline></SPAN></DIV></DIV></BLOCKQUOTE>
<P> </P>
<P>My original query remains, since both areas I was referring to are in
the UK, about 70km away from each other.</P>
<P>I can see advantages and disadvantages to storing polygons in the main
OSM database. One disadvantage I guess is it will dramatically increase
the amount of data in the database, but I presume it would have the advantage
that the polygons can be edited / amended using the usual OSM tools, so that
alterations could be made by people with local knowledge.</P>
<P>Once 1) & 2) are agreed I'd be happy to assist if I can.</P>
<P>David</P></BODY></HTML>