[ gpsdrive ] Nautical maps

[Hamish]

Bill wrote:
> I would dearly appreciate a tutorial on how to generate a GPSDrive
map
> using the free NOAA EMC maps,

ok, for vector data:

1) get NOAA S-57 (EMC) data
   http://nauticalcharts.noaa.gov/mcd/enc/download.htm
   nice preview:
http://www.oceangrafix.com/o.g/search-nautical-charts.html
2) install GDAL/OGR from www.gdal.org
3) test for S-57 support with 'ogrinfo --formats | grep S57'
4) Try to load it with a nice viewer like Quantum GIS (www.qgis.org)
5) Import S-57 data into GRASS GIS (grass.osgeo.org) with v.in.ogr
6) Set zoom, dispaly layers, colors, line widths, labels, etc. in GRASS
7) Export & register the GpsDrive tile with d.out.gpsdrive
8) create GpsDrive waypoints at bouy lat/lons and verify that tile
lines up

I am downloading a couple of NOAA ENCs now, I'll give it a try and post
the results.


for georeferenced raster data (GeoTIFF, BSB) you can use the
gdal_slice.sh script which calls gdal_translate in a loop.


> tailored to the neophyte Linux user.

The www.gpsdrive.de webpage says "GpsDrive - Navigation Software for
Linux". It may be more appropriate to call that "for UNIX" or "for
Linux and Mac". GpsDrive runs well on a Mac (I've built using Fink), it
seems a pity not to include all those users.


> A Google search of GPSDrive in marine applications turns up
> essentially nothing.

This list & its archives is the best place to look+ask.


Pat wrote:
> It would be great if someone in the know made an importing howtoo for
> newbies.
...
> So if the people who know this stuff, or have figured it out could
> write a howtoo ....

I had put some hints into the old GpsDrive MediaWiki, but that has gone
away. You might still be able to find the content via archive.org.
I am happy to host something on my google pages webspace, but it would
be nice to revive the wiki so everyone can contribute ideas. For
solutions using d.out.gpsdrive we could use GRASS's wiki.


Doug wrote:
> I supplemented by using Google Earth for which I found a series of
> graphics someone had collected for the major harbours of the world
> of which fortunately Toronto was included. 

link please? :)


> I has hoped by now someone had interfaced the free distribution from
> NOAA, but so far I haven't found it.

try above. Both GDAL and GRASS (>=6.3) are fully scriptable so
something
could easily be done to automate tile creation.


> I would be willing to kick in a Ben Franklin to fund a coop student
in
> the summer of code to paste something together.....how many others
> would due the same?

IMO efforts are better directed at replacing the 1280x1024 tile and
center LL + scaling factor in map_koord.txt with libgdal and the
ability to dynamically load + crop the current region from the original
georeferenced map files without any reprocessing by the user. It just
takes some work and IMHO is really holding the project back from
what it could be.

I see no reason why the S-57 vector data could not be integrated into
GpsDrive in the same way OpenStreetMap has been. (NOAA products are
without copyright)

Documentation & tutorials are worth their weight in gold, and so
contributing back to the project is the preferred method of payment as
far as I'm concerned.


Hamish


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