----- Original Message -----
From: "Steve Bennett" <stevag...@gmail.com>
To: "Paul Norman" <penor...@mac.com>
Cc: <talk@openstreetmap.org>
Sent: Sunday, April 01, 2012 12:58 AM
Subject: Re: [OSM-talk] Coastline Update
On Sat, Mar 31, 2012 at 2:26 PM, Paul Norman <penor...@mac.com> wrote:
There are no significant multi-square flooded or dry areas. The following
areas have significant number of error points:
Pudget Sound in Washington State
The mouth of the Columbia river in Washington
The Eastern Australia coast
Speaking as an Eastern Australian coast dweller, what do we need to
do? What do the red spots in the map mean, and what do we need to do
about them?
Steve
What do the red dots mean?
the red dots represent where there is a possibility of a gap in gap in the
OSM coastline ways following the deletion of data which is happening this
weekend. This "gap" could just be a few metres, or the dot could represent
the start of a missing section of many 10's (or possibly 100's) of
kilometres.
In order for Mapnik to render coastline correctly there needs to be a
continuos line of coastline ways around all landmasses. Any gaps in the
coastline ways will lead to poor rendering.
What can we do about this ?
The missing sections in the coastline will need to be completed. There are
various ways this can be done. In Australia there is the option of:
tracing from Bing or AGRI.
there is also the possibility of importing data. I did offer on the talk-au
[1] list to re-import PGS data (relatively low quality), though I did ask
whether it was better to delay and wait until someone had time to reimport
ABS data
If you are going to add in any coastline data please be aware that the
direction it is drawn is very important. It must be drawn so that the sea
is on the right hand side of the way.
Although it would be possible in the next few days to redraw some coastline
using JOSM and store this off line ready to upload when the database comes
back on line, my opinion is that it is better now to do nothing until the
new database comes back on line in a few days. I am sure that Paul Norman
will then regenerate the shapefiles from which "the reds dots" are derived,
and the error maps will be updated to show actual positions where coastline
ways are then missing .
Regards
David
[1] http://lists.openstreetmap.org/pipermail/talk-au/2012-March/008957.html
Steve
_______________________________________________
talk mailing list
talk@openstreetmap.org
http://lists.openstreetmap.org/listinfo/talk
_______________________________________________
talk mailing list
talk@openstreetmap.org
http://lists.openstreetmap.org/listinfo/talk
