I've just had a thought on this one! I wonder if the BUFFER is actually a buffer to both sides of the XY specified in "MAPXY". That would account for the resultant image looking approximately twice the distance across that I'm looking for e.g. a BUFFER of 2000 would result in an image that's actually 4000m (4km) across. I'll have to go back do a bit of experimenting.
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Donald Kerr Sent: 08 January 2009 17:47 To: [email protected] Subject: [mapserver-users] CGI mapserv.exe - BUFFER I'd appreciate it if someone could give me some clarification please? I am using the following url to return an image: http://localhost/cgi-bin/mapserv.exe?map=/ms4w/os.map&mode=map&mapsize=500+4 00&mapxy=258544+665909&layers=all&buffer=2000 The documentation states, "BUFFER [distance] - A distance, in the same coordinate system as the map file, used in conjunction with MAPXY to create an new map extent". The coordinate system is in metres so I would expect that the width of the image (500px) would be 2000m (2km). That doesn't seem to be the case i.e. the returned images is, at a guess, double that. I need clarification on what "buffer" is actually doing. No doubt I'm way off the mark with the deduction above! Many thanks. Regards, Donald Kerr _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
