[ka-Map-users] Controlling the number of points using addObjectGeo

[Aaron Koning]

I am not sure about MySQL, but if you use PostGreSQL and the PostGIS spatial
extension you can query a db table using a spatial bounding box (e.g. the
spatial extents of the tile) (
http://postgis.refractions.net/docs/ch06.html#id2789996). This provides the
points for the area of interest only.

In fact, you might as well create a PostGIS layer and load it into a
MapServer map file since you have to get the points from a database anyway.
MapServer then does the 'extents' query and adds the points to the map for
you (if I'm not mistaken).

Aaron

On 2/28/06, Base Bloc <chris at basebloc.com> wrote:
>
>  Dear all,
>
>
>
> First off I would like to say that ka-map 0.2 is a fantastic piece of kit
> and thanks for all the work that people have put in to this.
>
>
>
> I am currently building an application using 0.2 and I am using the
> addObjectGeo function to add markers along with mouseover events (pop-up
> windows) to the map. All is working as it should and is looking good. My
> concern now is the number of markers; the application is covering most of
> Southeast Asia and the number of markers is going to be high. I am looking
> to use Ajax to connect to a MySQL database to retrieve the point data
> relevant to the area of the map being viewed, as if all of the points were
> to be retrieved in one go it would result in a serious performance hit for
> the user.
>
>
>
> I'm no ka-map expert, but I was wondering how ka-map does this efficiently
> with the tiles; as in it gets x number of tiles closest to the area being
> viewed then moves outwards, is there anyway to use the variable(s) that are
> being sent to the server to request the tiles to also query the database and
> return the point data in an equally efficient manor?
>
>
>
> Thanks in advance for your thoughts.
>
>
>
> Chris
>
>
>
>
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Christopher Brown
>
> Head of Internet Development
>
> Base Bloc Cambodia
>
> #33, 123, Phnom Penh, Cambodia.
>
> P.O. Box 2086
>
> www.basebloc.com
>
> Tel (+885) 12 315 302
>
>
>
> _______________________________________________
> ka-Map-users mailing list
> ka-Map-users at lists.maptools.org
> http://lists.maptools.org/mailman/listinfo/ka-map-users
>
>
>


--
+--------------------------------------------
|  Aaron Koning
|  Information Technologist
|  Prince George, BC, Canada.
+--------------------------------------------
|  http://datashare.gis.unbc.ca/fist/
|  http://datashare.gis.unbc.ca/gctp-js/
+--------------------------------------------
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