Zoom & Pan

[Milo van der Linden]

Hello Clinton!

Zoom and Pan is Clientside functionality. For this an application needs 
to be enhanced with Javascript. As an example:
- When you drag a box, your browser needs to respond to the MouseDown 
and MouseUp and even MouseMove events. Then it has to store temporary 
variables telling it where you are zooming. When the MouseDown event is 
fired, you connect to the server and fire mapserv to pass a new image.

If this sounds to complex, you might consider looking at available 
dynamic client software for mapserver. Take a look at the following:

www.openlayers.org - Good javascript library to have dynamic 
mapfunctions, but needs mapserver to be installed as a WMS server
www.cartoweb.org - reasonably documented if your requirements are 
straight forward.
http://ka-map.maptools.org/ - not a lot development going on there, but 
it might fit your needs.

Remember, mapserver is mostly an excellent SERVER, if you want more from 
clients then the old fashioned request - response stream where browsers 
react on a single click; take a look at one of the clients mentioned above.

Good luck!



Clinton Olsen schreef:
> Hello,
>
> I would like to know how I can take the application I created from the tutorial, 
> and add zoom windows, so I can click on the viewer and drag a window across 
> a certain area to zoom in or out.  And I need to know if there is a way I can 
> make my application pan by using the click and drag method.  For reference 
> my application can be found at the internet address below.
>
> http://www.emerycounty.com:90/cgi-bin/mapserv.exe?
> map=/emerycounty/ms4w/apps/tutorial/htdocs/lawcem-
> maps/lawcem.map&layer=emeryroads&layer=emeryborder&layer=living&layer=bu
> riedother&layer=plots&layer=fences&layer=gravemarkers&layer=cemlabels&zoom
> =0&mode=browse&root=/tutorial&program=/cgi-
> bin/mapserv.exe&map_web_imageurl=/ms_tmp/&map_web_imagepath=/emeryco
> unty/ms4w/tmp/ms_tmp/&map_web_template=index.html&mapext=1357154+65
> 19737+2340584+7175357
>
> Please let me know what all you need in order to give me some ideas.  
>
> Thanks.
>
>