[Mapserver-users] Can't seem to get the projection correct

Martin, Daniel DMartin at erac.com
Tue Feb 18 12:19:54 EST 2003


That's the output "map".  The input projection is stored in the TAB file
itself.  In MapServer, I believe OGR takes care of determining the
projection in the TAB file for MapServer.  The projection on the LAYER
object can be omitted without any effect on my maps.

I know this whole thing may seem picky.  I noticed it right off, but I was
going to let it slide.  But the first thing my boss said when I showed him
all the maps I've put together with MapServer was "Looks great, but why are
they squished?".  *sigh*

-Dan

> -----Original Message-----
> From: Ed McNierney [mailto:ed at topozone.com]
> Sent: Tuesday, February 18, 2003 11:13 AM
> To: Martin, Daniel; mapserver-users at lists.gis.umn.edu
> Subject: RE: [Mapserver-users] Can't seem to get the 
> projection correct
> 
> 
> Daniel -
> 
> I'm not a MapInfo user, but is MapInfo telling you the 
> projection of the
> output image you're viewing, or the projection of the input 
> data you're
> using?
> 
> 	- Ed
> 
> -----Original Message-----
> From: Martin, Daniel [mailto:DMartin at erac.com] 
> Sent: Tuesday, February 18, 2003 11:52 AM
> To: Ed McNierney; mapserver-users at lists.gis.umn.edu
> Subject: RE: [Mapserver-users] Can't seem to get the 
> projection correct
> 
> Well, perhaps MapInfo is lying to me, but it says the projection I am
> after
> *is* latlong.  It says:  "Latitude/Longitude (NAD 27 for the 
> Continental
> US)"
> 
> I've tried NAD 27:
>     proj=latlong
>     ellps=clrk66 
>     datum=NAD27 
>     no_defs
> 
> But when I do, my map simply disappears!
> 
> Thanks,
> Dan Martin
> 
> > -----Original Message-----
> > From: Ed McNierney [mailto:ed at topozone.com]
> > Sent: Tuesday, February 18, 2003 10:42 AM
> > To: Martin, Daniel; mapserver-users at lists.gis.umn.edu
> > Subject: RE: [Mapserver-users] Can't seem to get the 
> > projection correct
> > 
> > 
> > Daniel -
> > 
> > You need to know what projection you're trying to emulate.  
> It is VERY
> > unlikely that any map you find in an atlas is using the "geographic"
> > projection you're using in your map.  The example you show 
> > from MapInfo
> > *might* be a Mercator projection (which you might commonly find in
> > atlases, too), which STRETCHES areas near the poles (i.e. Greenland
> > isn't nearly as big as most people think).  That's why your 
> > unprojected
> > data might appear squished by comparison.
> > 
> > 	- Ed
> > 
> > Ed McNierney
> > President and Chief Mapmaker
> > TopoZone.com / Maps a la carte, Inc.
> > 73 Princeton Street, Suite 305
> > North Chelmsford, MA  01863
> > Phone: (978) 251-4242  Fax: (978) 251-1396
> > ed at topozone.com
> > 
> > 
> > -----Original Message-----
> > From: Martin, Daniel [mailto:DMartin at erac.com] 
> > Sent: Tuesday, February 18, 2003 11:28 AM
> > To: mapserver-users at lists.gis.umn.edu
> > Subject: RE: [Mapserver-users] Can't seem to get the 
> > projection correct
> > 
> > David,
> > Thanks for your suggestion.  I tried it but it's not quite what I'm
> > looking
> > for.  I want horizontal lines of latitude, as I have now.  I'd just
> > rather
> > have the vertical less squished.
> > 
> > All,
> > I've attached a map displaying identical data in MapInfo and 
> > MapServer,
> > with
> > both applications' projection set to latlong.  In comparison you can
> > clearly
> > see that the MapServer output is vertically squished.
> > 
> > This isn't limited to MapInfo.  Nearly any map I can find of a
> > particular
> > area from any source (Mapquest, an atlas, anywhere) is 
> similar to the
> > MapInfo view, and the MapServer view looks "squished", for lack of a
> > better
> > term.
> > 
> > I've attached a map file below.
> > 
> > I appreciate the help guys,
> > Dan Martin
> > 
> > #
> > # Start of map file
> > #
> > NAME NorthAmerica
> > STATUS ON
> > SIZE 800 600
> > UNITS dd
> > IMAGECOLOR 255 255 255
> > FONTSET "..\fonts\fontset.txt"
> > SYMBOLSET "..\symbols\symbolSet.txt"
> > IMAGETYPE PNG
> > 
> > #
> > # Projection definition, consult the PROJ.4 documentation for 
> > parameter
> > discussion
> > #
> > PROJECTION
> > 		proj=latlong
> > END
> > 
> > #
> > # Start of web interface definition (including WMS enabling 
> metadata)
> > #
> > WEB
> >   TEMPLATE ../Clients/rosaClient.html
> >   MINSCALE 1000
> >   IMAGEPATH "\inetpub\wwwroot\temp\"
> >   IMAGEURL "/temp/"
> > 	HEADER "../queryTemplates/query_head.html"
> > 	FOOTER "../queryTemplates/query_foot.html"
> > 	EMPTY "../MapServer/noRecords.html"
> > END
> > 
> > QUERYMAP
> >   SIZE 200 200
> >   STATUS ON
> >   STYLE HILITE
> >   COLOR 255 255 0
> > END
> > 
> > 
> > # Start of reference map
> > 
> > REFERENCE
> >   IMAGE ../referenceImages/us-reference.gif
> >   EXTENT -124.986016 24.403641 -66.490832 68.268767
> >   SIZE 160 120
> >   STATUS ON
> >   COLOR -1 -1 -1
> >   OUTLINECOLOR 255 0 0
> > END
> > 
> > 
> > # LEGEND object
> > LEGEND
> >    STATUS off		 
> >    KEYSIZE 40 16
> > 	 OUTLINECOLOR -1 -1 -1
> >    TEMPLATE "../legendTemplates/checkBox_legend.html"
> > END
> > 
> > #
> > # Start of scalebar
> > #
> > SCALEBAR
> >   IMAGECOLOR 0 125 90
> > 	BACKGROUNDCOLOR 150 230 150
> > 	OUTLINECOLOR 255 255 255
> >   LABEL
> >     COLOR 255 255 255
> >     SIZE large
> >   END
> >   STYLE 0
> >   SIZE 200 10
> >   COLOR 255 255 255
> >   UNITS miles
> >   INTERVALS 3
> >   TRANSPARENT TRUE
> >   STATUS TRUE
> > END
> > 
> > # Start of layer definitions
> > #
> > LAYER
> >   NAME "USA"
> > 
> >   PROJECTION
> >     "proj=latlong"
> >   END
> > 
> >   CONNECTIONTYPE OGR
> >   CONNECTION "\GISData\Namerca\USA\Usa_Maps\USA.TAB"
> > 
> > 	STATUS DEFAULT
> >   TYPE POLYGON
> >   CLASS
> >     COLOR 225 225 185
> >     OUTLINECOLOR -1 -1 -1
> >   END
> > END
> > 
> > LAYER
> >   NAME "Canada"
> > 
> >   PROJECTION
> >     "proj=latlong"
> >   END
> > 
> >   CONNECTIONTYPE OGR
> >   CONNECTION "\GISData\Namerca\Canada\Canada.TAB"
> > 	STATUS DEFAULT
> > 
> >   TYPE POLYGON
> > 
> >   CLASS
> >     COLOR 225 225 185
> >   END
> > END
> > 
> > END
> > > -----Original Message-----
> > > From: Ed McNierney [mailto:ed at topozone.com]
> > > Sent: Tuesday, February 18, 2003 9:59 AM
> > > To: Martin, Daniel; mapserver-users at lists.gis.umn.edu
> > > Subject: RE: [Mapserver-users] Can't seem to get the 
> > > projection correct
> > > 
> > > 
> > > Daniel -
> > > 
> > > Unfortunately <g>, the map looks just fine.  What were you 
> > expecting?
> > > Do you have a sample of what a "geographic" projection of 
> > > that area does
> > > look like?  Canada's going to get stretched quite a bit that way.
> > > 
> > > 	- Ed
> > > 
> > > Ed McNierney
> > > President and Chief Mapmaker
> > > TopoZone.com / Maps a la carte, Inc.
> > > 73 Princeton Street, Suite 305
> > > North Chelmsford, MA  01863
> > > Phone: (978) 251-4242  Fax: (978) 251-1396
> > > ed at topozone.com
> > > 
> > > 
> > > -----Original Message-----
> > > From: Martin, Daniel [mailto:DMartin at erac.com] 
> > > Sent: Tuesday, February 18, 2003 10:51 AM
> > > To: mapserver-users at lists.gis.umn.edu
> > > Subject: [Mapserver-users] Can't seem to get the 
> projection correct
> > > 
> > > I've been playing with my projections for some time now, with no
> > > success.
> > > I'm using entirely OGR data (MapInfo data to be exact).  All 
> > > the data is
> > > in
> > > latlong.  No matter what I try, I end up with maps that are 
> > vertically
> > > challenged (squished).  See the attachment.
> > > 
> > > I'd appreciate any advice you can offer.
> > > 
> > > Thanks,
> > > Daniel Martin
> > > 
> > 
> 



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