[mapserver-users] SWF output demo site?

[Daniel Morissette]

Bart van den Eijnden wrote:
> 
> I thought with SWF less frequent client-server contact is needed. So e.g.
> zoom in does not require a new request. But after zooming in it seems like
> a new map is retrieved from the server. Or is the client busy with zooming
> in on the SWF image when it says retrieving image? How does this work, is
> my statement only valid for vector SWF layers?
> 


It depends on how the application is built.  You can control via the
mapfile which layers are output as rasters and which ones are outpout as
vectors to the Flash client.

This specific application passes all layers as rasters, so the client
has to request a new map from the server everytime as you noticed.

It would be possible to make all layers vectors and then the client
could be instructed to zoom into the vector data without going back to
the server.  However this could involve huge amounts of data to transfer
and you would likely have to decide on an arbitrary threshold to use in
generalizing the vectors that you pass to the client anyway.

The best compromise is to use raster mode for backdrop layers, and
vector mode for layers of points of interest for instance... so you get
the interactivity of Flash on your vector features, and don't have to
transfer megabytes of vectors to the client... something that the Flash
client could probably not handle anyway.

Daniel
-- 
------------------------------------------------------------
 Daniel Morissette               morissette at dmsolutions.ca
 DM Solutions Group              http://www.dmsolutions.ca/
------------------------------------------------------------