[mapserver-users] SWF output demo site?

[Bart van den Eijnden]

Hi Daniel,

I remain with one basic question after your clear response.

What is the advantage of using raster SWF layers above normale GIF or JPG 
images?

Thanks,
Bart

On Tue, 01 Jul 2003 12:14:10 -0400, Daniel Morissette 
<morissette at dmsolutions.ca> wrote:

> 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



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