[mapserver-users] Using MapServer with ERMapper's Image Web Server (IWS)

[Robert Crossley]

Tyler,

We are currently implementing a IWS/ Mapserver app. 

But, the integration works the other way around to what you think I'm afraid.  IWS delivers the images as layers to the client and when vectors are also used, the vectors are also 
delivered by IWS as an image layer overlay to the client.  The image layers are handled by a client-side plugin.  On a change of extent, the plug-in triggers a request for new parts of 
the image that it doesn't already have and a new vector layer overlay.  The procedure is quite well explained in their docs, and even code for the integration of Mapserver.

Its disadvanage is its requirement for an 400K  ActiveX download or an plugin for Netscape, but if you have to deliver images, it has a lot of advantages.  For a start, an aerial photo / 
satellite base is only streamed down once, rather than for each separate request, and thus a change of extent or zoom means only a download of a small gif rather than a large jpg.  
Then it only requests the parts of the image that it doesn't have already, meaning that if you come back to a part of an image that you looked at before, it is already on the client 
machine.  Its also not freeware for reasonable sized installations.

One advantage with the download, is that if the client already has to download a plugin, then they may as well download a full client side app, and you can incorporate a lot of client 
side functionality that would be difficult otherwise.  IWS plan on releasing a java version of their plugin later this year that may change the options though.

Robert.

13/04/2002 03:42:27, "Tyler Mitchell" <TMitchell at lignum.com> wrote:

>Is anyone using MapServer with ERMappers IWS?  I see a MapServer demo on
>their site about integrating MapServer with IWS, but I was wondering if
>anyone can tell me how I could add a layer into my map file that would grab
>an image from IWS (I assume using WMS).
>
>Tyler
>
>
>

Robert Crossley 
Robert Crossley & Associates
9 Short St
New Brighton NSW 2483
AUSTRALIA

P: 02 6680 1309
F: New Connection
M: 0419 718 642
E: robert at wotzhere.com