Spatial Extent and Projection

[Bart van den Eijnden]

Hi,

1)

I am assuming you have a dataset for Hampton Roads, Virginia, USA, or not?

If so, you can use gdalinfo (for raster data) or ogrinfo (for vector data)
to get an extent. E.g.

ogrinfo -summary myshape.shp

For more info see:

ogrinfo:
http://www.gdal.org/ogr/ogr_utilities.html

gdalinfo:
http://www.gdal.org/gdal_utilities.html#gdalinfo

2)

The easiest way to use PROJ.4 within Mapserver is using EPSG codes for
projections. You can also define projections through parameters such as
ellipsoid etc.

http://mapserver.gis.umn.edu/doc44/mapfile-reference.html#projection

There is a file which contains epsg codes, for instance for Netherlands we
use EPSG:28992, the entry in the epsg file of proj is (this format is
called WKT):

# Amersfoort / RD New
<28992> +proj=stere +lat_0=52.15616055555555 +lon_0=5.38763888888889
+k=0.999908 +x_0=155000 +y_0=463000 +ellps=bessel +units=m +no_defs
no_defs <>

If I want to use this in Mapserver I use:

PROJECTION
   "init=epsg:28992"
END

You can define projection objects for every LAYER (defining the source
projection of your data), and at the MAP level (defining which projection
you want to use for your output map).

Hope this helps.

Best regards,
Bart

On Sat, 19 Mar 2005 14:30:37 -0500, Giridhar Manepalli
<gmanepal at GMAIL.COM> wrote:

> Hello All,
> Can anyone tell me the EXTENT(Spatial Extent for Mapfile) of Hampton
> Roads, Virginia, USA. I will be really helpful for my project.
>
> Also, if you can tell me where can I get such information.
>
> The PROJ.4 is quite useful for Mapserver. Although there is
> documentation about it, from its website, I would be glad to get some
> pointers about it, specifically how to use that in Mapserver etc.
>
> I really appreciate, if anyone can help me in both these issues.
>
> Although, its been few days since I started using Mapserver, I am
> really infatuated by its sheer
> capability :-)
>
> Thanks and Regards,
> Giridhar
>



--
Using Opera's revolutionary e-mail client: http://www.opera.com/m2/