[talk-ph] better ways to coordinate coastline mapping?

maning sambale emmanuel.sambale at gmail.com
Tue Jul 6 02:31:01 BST 2010


@ ed,
The technique is outlined here:
http://wiki.openstreetmap.org/wiki/Talk:WikiProject_Philippines/Coastline_Corrections

Couple of suggestions:
1. short link to the coastline correction wikipage
2. enable link to editors only at higher zoom level (perhaps 15-17?)
3. should be an osm-ph image of the week

On Tue, Jul 6, 2010 at 9:20 AM, Ed Garcia <eppgarcia at gmail.com> wrote:
> Wow! amazing ... how do you detect "sawtoothness"?  can you teach this at
> the skillshare?  OSM genius ka talaga!
>
> Anyway, I take note of the sawtooth patterns between Lucena and Pagbilao
> Quezon ... I have corrected this already but the sawtooth appears only on
> higher zoom-out levels now.  Does this mean it is good as "done" now?  It
> still appears on yoursawtooth_coastlines map though.
>
> ed
>
> On Tue, Jul 6, 2010 at 1:04 AM, Eugene Alvin Villar <seav80 at gmail.com>
> wrote:
>>
>> HI guys,
>>
>> Here's an *initial* webmap showing where the jagged coastlines are as of
>> July 3:
>> http://forge.codedgraphic.com/osm/sawtooth_coastlines/
>>
>> The larger the circle, the more jagged steps there are to clean up.
>>
>> Sorry, there's no link going to Potlatch or JOSM/Merkaartor. I'll add that
>> up when I learn more of OpenLayers. But for now, this will have to do.
>>
>> Enjoy!
>>
>> Eugene
>>
>> On Mon, Jul 5, 2010 at 9:30 AM, maning sambale
>> <emmanuel.sambale at gmail.com> wrote:
>>>
>>> We missed the June target to to finish the 10 largest islands.
>>>
>>> http://wiki.openstreetmap.org/wiki/WikiProject_Philippines/Coastline_Corrections#Priorities
>>>
>>> That's OK.  All we need is to finish mainland Mindanao and we can set
>>> our radar to the next 20 on the list.
>>> We are also working on some webmap to visualize the "sawtooth".  More
>>> on that when its ready.
>>>
>>>
>>> On Sun, Jul 4, 2010 at 5:48 PM, maning sambale
>>> <emmanuel.sambale at gmail.com> wrote:
>>> > I can load it in my public dropbox.
>>> >
>>> > On Sun, Jul 4, 2010 at 2:23 PM, Eugene Alvin Villar <seav80 at gmail.com>
>>> > wrote:
>>> >> Hi guys,
>>> >>
>>> >> Once we are done with the large islands, the next step is to do the
>>> >> smaller
>>> >> islands. Ian Haylock has helpfully provided the PGS coastlines[1] for
>>> >> the
>>> >> Philippines last year[2] which he edited to combine ways. PGS itself
>>> >> was
>>> >> automatically generated by a software by analyzing the Landsat
>>> >> imagery.
>>> >> Unfortunately, Ian's file was hosted on a free file server and has now
>>> >> expired but I think several people on the mailing list managed to
>>> >> download
>>> >> it.
>>> >>
>>> >> I tried opening the file last year in Merkaartor but my old laptop
>>> >> couldn't
>>> >> handle the data. Now that I have a 4GB-RAM laptop, loading the data
>>> >> into
>>> >> Merkaartor is very manageable. Using the PGS coastlines is much, much
>>> >> easier
>>> >> than tracing Landsat by hand. I tried this with Homonhon Island and
>>> >> editing
>>> >> is way faster than actually uploading it[3]. Hehehe. What I did was to
>>> >> delete the SRTM-derived coastline[4] and replace it with the PGS
>>> >> coastline[5].
>>> >>
>>> >> I think uploading the PGS coastlines is better for the smaller
>>> >> islands. I'll
>>> >> see what we can do to have the PGS coastlines (55MB) uploaded
>>> >> somewhere.
>>> >>
>>> >> [1] http://wiki.openstreetmap.org/wiki/Prototype_Global_Shoreline
>>> >> [2]
>>> >> http://lists.openstreetmap.org/pipermail/talk-ph/2009-June/001071.html
>>> >> [3] http://www.openstreetmap.org/browse/changeset/5129873
>>> >> [4] http://www.openstreetmap.org/browse/way/4327906
>>> >> [5] http://www.openstreetmap.org/browse/way/65592780
>>> >>
>>> >> Eugene
>>> >>
>>> >>
>>> >> On Thu, Jun 17, 2010 at 8:20 PM, maning sambale
>>> >> <emmanuel.sambale at gmail.com>
>>> >> wrote:
>>> >>>
>>> >>> UPDATE. Only two islands from the top ten need some coasty coastline
>>> >>> love.
>>> >>>
>>> >>>
>>> >>> http://wiki.openstreetmap.org/wiki/WikiProject_Philippines/Coastline_Corrections
>>> >>>
>>> >>> Anyone working on Negros and Mainland Mindanao?
>>> >>>
>>> >>
>>> >>
>>> >
>>> >
>>> >
>>> > --
>>> > cheers,
>>> > maning
>>> > ------------------------------------------------------
>>> > "Freedom is still the most radical idea of all" -N.Branden
>>> > wiki: http://esambale.wikispaces.com/
>>> > blog: http://epsg4253.wordpress.com/
>>> > ------------------------------------------------------
>>> >
>>>
>>>
>>>
>>> --
>>> cheers,
>>> maning
>>> ------------------------------------------------------
>>> "Freedom is still the most radical idea of all" -N.Branden
>>> wiki: http://esambale.wikispaces.com/
>>> blog: http://epsg4253.wordpress.com/
>>> ------------------------------------------------------
>>>
>>> _______________________________________________
>>> talk-ph mailing list
>>> talk-ph at openstreetmap.org
>>> http://lists.openstreetmap.org/listinfo/talk-ph
>>
>>
>>
>> --
>> http://vaes9.codedgraphic.com
>>
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>
>
>
> --
> website administrator:
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>
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-- 
cheers,
maning
------------------------------------------------------
"Freedom is still the most radical idea of all" -N.Branden
wiki: http://esambale.wikispaces.com/
blog: http://epsg4253.wordpress.com/
------------------------------------------------------




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