Architectural Question

[Steve Lime]

Hi Nelson: That's certainly the trend these days, change only what needs changing. For
that to work you need smarter software on the client. The basic issue is that MapServer
enforces square pixels and as a result it may change the requested extent to match the
requested image size. You have no way to get both the new extent and the image back 
in the same request. Actually you do using a template to return the computed extent and
the created image, e.g.:

img:[img]
extent:[mapext]

 but it's nicer to use MapServer as just an image engine.

Solutions like MapBender, OpenLayers, MapBuilder, Ka-map and others manage extents on
the client and send the appropriate requests for images to MapServer, a WMS server or
whatever. I use dbox here and it manages the coordinates in javascript and sends requests
to MapServer (mode=map) so that it doesn't have to adjust extents and it becomes easier
to just modify the map itself. Here are some examples:


 - http://www.dnr.state.mn.us/waters/csg/index.html 
 - http://maps.dnr.state.mn.us/waters/csg/station_mapper.html?mapxy=481573.570471947+4900561.10653818&scale=100000&id=39101001&layers=roads+bdry_munipy3+wsh_hunitpy3+sites+strm_baseln3+shdr_clrim3+lakes
 - http://www.dnr.state.mn.us/hunting/moose/zones2007/zone_report.html?map=/usr/local/mapserver/apps/faw/moose/moose.map&mode=itemquery&qlayer=zone_query&qstring=zone_id%3d25
 - http://maps.dnr.state.mn.us/tools/dbox-dev/example/example_fullscreen.html  (flaky in IE6)
 
In all of these the maps update, not the page. Anyway, lot's of choices!

Steve


>>> On 7/3/2007 at 8:05 PM, in message
<200707040105.l6415WWj008860 at sprint2.tenix.com>, LITTLE Nelson
<nelson.little at TENIX.COM> wrote:
> Hello Mapserver users,
> 
>  
> 
> I have developed a web based mapserver application using Java Mapscript
> & Servlets and it works well and looks great. I currently use the Rosa
> Applet as the map window display. My application is very similar in
> behaviour to the Mapserver Atlas application (AKA gmap) (online:
> http://www.mapsherpa.com/gmap/gmap75.phtml). 
> 
>  
> 
> Whenever the user hits 'Redraw Map' or clicks on a tool button, it
> causes the whole pages to be refreshed. My question is how could this be
> changed so that only the map window is refreshed, not the whole page? I
> know this is an architectural type question which is not really related
> to Mapserver, but if anyone would know the answer it would be the people
> on this list.
> 
>  
> 
> Thanks,
> 
> Nelson
> 
> 
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