[mapserver-users] map scale questions

[Bjarni Pjetursson]

I was facing the exactly same puzzle a month ago. Someone should emphasize
this issue in the mapfile documentation.
/Bjarni 

-----Original Message-----
From: Alex Rice
To: Bjarni Pjetursson
Cc: mapserver-users at lists.gis.umn.edu
Sent: 06-08-02 18:38
Subject: Re: [mapserver-users] map scale questions


On Tuesday, August 6, 2002, at 05:08  AM, Bjarni Pjetursson wrote:

> if your data source is in lon/lat, your coordinates are stored in 
> degrees.
> You should therefore set the Mapserver map file units to "DD" (decimal
> degrees).

How embarrassing! I can't believe I over looked "dd" in the 
mapserver documentation!  Also, I had printed out the proj user's 
manual last night, but haven't read much of it yet.

> If your data is in any other projection, your coordinates are stored
in
> cartesian coordinates (for example m, km, mi). Theese coordinates 
> are much
> larger than decimal degrees. Most likely this is the reason you see
the
> weird scale. You must set your map file units to the appropriate 
> cartesian
> unit.
>
> You can use freeware viewing tools like Geographic Explorer
> (http://www.bluemarblegeo.com/products.asp?id=5) to display the actual
> values in your data files.

Thanks for the tips.

Alex Rice, Software Developer
Architectural Research Consultants, Inc.
alex_rice at arc.to
alrice at swcp.com