[mapserver-users] Looking for suggestions...

[Puneet Kishor]

> -----Original Message-----
> From: Williams, Chris D. [mailto:WILLIC10 at mail.northgrum.com]
> Sent: Tuesday, August 27, 2002 12:10 PM
> To: 'Steve Lime'; mapserver-users at lists.gis.umn.edu
> Subject: RE: [mapserver-users] Looking for suggestions...
> 
> 
> Thanks for the help...here are some followup...
> 
> 1)  I am new to shapefiles...how do you check the extents of 
> a shapefile?

You could use Arcview if you have it.

Else, if you are on a *nix box and have compiled Mapscript, you could use
the shpinfo.pl script to get all manner of info on the shapefile. You could
easily modify that script to only spit out the extent, if you so want. And
you might also find a thusly modified script somewhere in the message
archives... one of the many Perl wonks on this list had already done that
for someone else.


> 2)  What I would like to do is have the user select a 
> bounding box and click
> a button that will fill in some form fields with the lat/lon 
> based on the
> that area.
> 

this would require Javascript. When you select any box on the screen you are
capturing screen coordinates. First step would be to transform those coords
to the geographic coords of your preference. Inserting those coords in the
form fields would then be trivial.

Hth,

pk/











> Thanks again!
> Chris
> 
> -----Original Message-----
> From: Steve Lime [mailto:steve.lime at dnr.state.mn.us]
> Sent: Tuesday, August 27, 2002 11:48 AM
> To: mapserver-users at lists.gis.umn.edu; Williams, Chris D.
> Subject: Re: [mapserver-users] Looking for suggestions...
> 
> 
> Hi Chris:
> 
> 1) That extent certainly covers the globe, but whether it's 
> appropriate
> depends on you
> shapefiles. Check their extents to be sure.
> 
> 2) You'd only define a projection if you are displaying a map in a
> different projection than
> your data. If everything is in lat/lon and you don't want to 
> display in
> an alternative projection
> then there's no need to define it. 
> 
> 3) Depends, but in most cases yes. You'll have to be more specific on
> what you want to do.
> 
> 4) The DNR site is back up, gremlins... jbox is an updated version of
> mapplet in which method
> names and so forth have been standardized/sync'd with a DHTML version.
> I wanted to use the
> same javascript base for either a Java or DHTML front end. That
> necessitated some changes
> to the applet, albeit minor ones.
> 
> Steve
> 
> >>> "Williams, Chris D." <WILLIC10 at mail.northgrum.com> 
> 08/27/02 09:34AM
> >>>
> Hello all.  I have been playing around with MapServer for the 
> past week
> and
> having some problems trying to understand how all the parts fit.  Here
> is
> what I am trying to do.
> 
> I have a single shape file that contains an outline of the 
> world.  What
> I am
> trying to do is use mapplet and create a query screen that I am get a
> decimal lat/lon from.  I have been able to hack apart the itasca demo
> using
> my .map file and my shape file with mapplet.  The problem I am running
> into
> now is the zooming function doesn't seem to work right.  All it wants
> to do
> is pan and not really zoom.  Here are some of the questions I have...
> 
> 1)  What should I be defining the EXTENT value as?  I 
> currently have it
> set
> to -180.0 -90.0 180.0 90.0.  Is this right?
> 2)  Do I need to use the projection latlong?  I would think so since I
> want
> to get lat/lon points from the image.  When I added the 
> PROJECTION item
> to
> my .map file, I get an error from the mapserv cgi saying: Projection
> library
> eror: major axis or radius = 0 or not given.
> 3)  Is there a way to take the pixal position and convert it to a lat
> long
> point?
> 4)  I have also looked at the Landview on the
> http://www.dnr.state.mn.us 
> website.  Would using the jbox class be better than mapplet?  I tried
> accessing the webpage today and it seems like none of the maps are
> working.
> 
> 
> I have attached the .map file and the .html files.  The shape file I
> am
> using can be found at http://www.vdstech.com/download/world.zip.
> 
> Thanks!
> Chris
>