[mapguide-users] Fusion and Themed Layers - usability

[Paul Spencer]

I think Jason's idea of using the bottom end of the scale + 1 would  
improve cacheability (?) but in the end it would be ideal if we could  
do the same thing with MapGuide that we did with MapServer which is to  
generate a strip of images for each layers/scale and a set of css  
offsets associated with them.  The image is only generated and loaded  
once, providing significant improvements to responsiveness and load  
time.

Cheers

Paul

On 5-Apr-09, at 11:59 AM, Tom Fukushima wrote:

> I know that this keeps coming up during discussions I have with  
> developers, however because it does not affect the responsiveness of  
> the viewer---that is, you can start using the viewer before the  
> legend images are all downloaded, fixing this for performance  
> reasons has taken a lower priority.
>
> If you don't want the images to download, you could set all the  
> layers ShowInLegend property to false.
>
> Off the top of my head, my suggestion for resolving this, is to  
> allow the map author to create the custom strip, store it somewhere  
> accessible by the web tier (perhaps as resource data or on disk),  
> and then allow it to be specified from the Map.
>
> Tom
>
> -----Original Message-----
> From: mapguide-users-bounces at lists.osgeo.org [mailto:mapguide-users-bounces at lists.osgeo.org 
> ] On Behalf Of Jason Birch
> Sent: Friday, April 03, 2009 4:04 PM
> To: mapguide-users at lists.osgeo.org
> Cc: fusion-dev at lists.osgeo.org; 'MapGuide at lists.osgeo.org; Internals  
> Mail List'
> Subject: RE: [mapguide-users] Fusion and Themed Layers - usability
>
> Heh,
>
> Yeah, I can see how that would be unmanageable.  I wouldn't be  
> surprised if your use case strains fusion to the level that it's not  
> workable for the current version or for 2.1.  I'm surprised it works  
> with the AJAX viewer, but maybe the viewer has a different strategy  
> for managing legend images.
>
> Ideally, MapGuide would support a GetLegendImageStrip operation that  
> Fusion could then use with CSS sprites to reduce (in your case,  
> dramatically) the number of requests to the server.  I believe that  
> there may be functionality for this in MapServer layer types in  
> Fusion 2.0, but I don't think there is in MapGuide.  Bob Bray put in  
> a ticket for this functionality a _long_ time ago, but unfortunately  
> I don't think any work has been done on it:  http://trac.osgeo.org/mapguide/ticket/22
>
> I think that there is a partial measure that could be done in Fusion  
> to improve the situation somewhat.  Currently, Fusion does a  
> reasonable job of caching images; it only requests a new legend  
> image once per scale range context switch.  However, the initial  
> request is done using the exact current scale.  If the request  
> instead used a fixed value within the scale range (bottom + x?) then  
> the images could be better cached by the browser.  If MapGuide sent  
> cache headers (last modified, based on the layer definition?) this  
> would also help.
>
> Any Fusion or MapGuide devs have thoughts on this?
>
> Jason
>
> -----Original Message-----
> From: djonio
> Sent: April-03-09 12:47 PM
> To: mapguide-users at lists.osgeo.org
> Subject: RE: [mapguide-users] Fusion and Themed Layers - usability
>
>
> Jason,
>
> I wanted to respond before the weekend so this is just a very brief  
> note. Fiddler shows about 8000 of these(I assume a series for each  
> LayerDefiniton):
> GET /mapguide/mapagent/mapagent.fcgi? 
> OPERATION 
> = 
> GETLEGENDIMAGE 
> &SESSION 
> = 
> 2f6bfde6 
> -0000 
> -1000 
> -805a 
> -001aa01bd46c_en_7F0000010AFC0AFB0AFA 
> &VERSION=1.0.0&SCALE=2770.0556443473797&LAYERDEFINITION=Library%3A%2F 
> %2FMIA%2FFacilities 
> %2FFCLTY3000_7 
> .LayerDefinition&THEMECATEGORY=10&TYPE=2&CLIENTAGENT=Fusion%20Viewer  
> HTTP/1.1
>
> And they appear to be 111 byte 16wX16h png images.
> This was "Showing the Legend" and then doing a Zoom. If the Legend  
> is not shown I can Pan and Zoom pretty good.
>
> I can invest a little more time in this next week. I certainly do  
> like this fusion layout and appearance and am sure the users will  
> to ... but it has to work. Obviously there are alternatives to  
> having a pre-built legend but I really wanted to avoid those alts  
> from the get-go. I will delve into it all more on Monday. Have a  
> good weekend.
>
> r,
> dennis
>
> -- 
> View this message in context: http://n2.nabble.com/Fusion-and-Themed-Layers---usability-tp2580125p2582561.html
> Sent from the MapGuide Users mailing list archive at Nabble.com.
>
> _______________________________________________
> mapguide-users mailing list
> mapguide-users at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapguide-users
> _______________________________________________
> mapguide-users mailing list
> mapguide-users at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapguide-users
> _______________________________________________
> mapguide-users mailing list
> mapguide-users at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapguide-users