Projection Issues

Frank Warmerdam warmerdam at POBOX.COM
Wed Feb 8 12:44:06 EST 2006


On 2/8/06, Neil Saunders <n.j.saunders at gmail.com> wrote:
> Hi Frank - Thanks very much for your continued help. I'm still only a
> the learning stage, and so am just having a play trying to get a
> working system going.
>
> For testing purposes, the shapefile file I'm using is here:
> http://www.cdc.gov/epiinfo/shape/Cntry00.zip
>
> What I'd like to do is load this shape file in to a PostGIS database,
> then have mapserver render it projected as mercator (WGS84?),
> overlayed with points I've got in another table (specified as
> Lat/Long). As you can probably tell, most of my lack of understanding
> revolves around projections - Are there any good resources you could
> point me towards regarding this?

Neil,

I think the main gap is that you need to express your EXTENT
in meters, which you can manually reproject from lat/long using
something like cs2cs (from PROJ.4).

There are some good general references about projections at
the bottom of:

  http://proj.maptools.org/

Best regards,
--
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent



More information about the mapserver-users mailing list