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RE: [mapserver-users] external links in a map



At 19:56 04/09/02, Ed McNierney wrote:
Ian -

While I don't disagree with your general approach, I think this is a very reasonable feature for MapServer, and I've been looking at it a bit myself. If it's reasonable to let MapServer generate point symbols or polygons on a map image, and it's reasonable for MapServer to have a "query" mode in which you click on those things to produce querymaps of that feature, then I think it's equally reasonable for that server to generate flyover labels, etc. for the same feature. It happens that HTML requires a completely different set of tags (imagemap) to do such a thing, but that's not MapServer's fault nor is it a good reason to not want MapServer to generate them.

What I do not particularly want is two SEPARATE tools traversing the same data set to generate two related outputs unless there's a deterministic way to ensure they are consistent. If GeoTools and MapServer don't render a polygon feature exactly the same way, my imagemap won't agree with my image. That may or may not be important to my application.
I fact I was proposing using MapServer should generate the image (preferably in WMS mode) while the client handles the pop ups or hovers based on info from the server (possibly acting as a Web Feature Server WFS). Certainly for hover/flyover labels you'd want to avoid the over head of a HTTP call each time, it's hard to optimize that stuff in a single program with out latency in too.

GeoTools is CERTAINLY worth investigating for this particular problem, but do think that it's a reasonable thing to want MapServer to do. Another good tool philosophy is that if you've got one tool that already knows how to do 90% of the job, it might be helpful to add the other 10%. I think they're both useful ways of looking at a problem.
In fact someone else suggested how to do some of it in existing mapscript so I'm off to read up on that as I'd previously overlooked templates in that regard.


        - Ed

Ed McNierney


Ian
Ian Turton, Centre for Computational Geography, School of Geography,
University of Leeds, Leeds, LS2 9JT. ***0113 3433392 - New Phone No***
URL: http://www.geog.leeds.ac.uk/staff/i.turton/