Moving Points

[Brent Fraser]

Jay,

    I assume you are eventually going to have a custom program to
automatically "receive" locations via email, ftp, etc and put them somewhere
(a datastore) where a viewing/display program like mapserver can access
them.

  Because of the need to regularly update the positions, using a database
(like PostgreSQL) as a data store is a good choice.  If you were to use a
shapefile or a text file to keep the locations, you may have file access
problems when the display program tries to read the datastore when they are
being updated.

  And as David Bitner points out, there are other good reasons to use a
database for this kind of data.

  As for the client side, when tracking slow moving objects (ships, trucks)
we use a plain html mapserver template rendering the symbols onto a png
file, automatically refreshing the graphic every 10 minutes or so.  If you
need to track faster moving things, or require more sophisticated functions
on the client, you may need to use Java, Javascript or some other
client-side scripting language to build functions to retrieve the positions
and see the symbols move in real time, appear animated, etc.

Brent Fraser
GeoAnalytic Inc
Calgary, Alberta, Canada


----- Original Message ----- 
From: "Jay Varner" <jay at SASSATLANTA.NET>
To: <MAPSERVER-USERS at LISTS.UMN.EDU>
Sent: Wednesday, July 26, 2006 7:54 AM
Subject: [UMN_MAPSERVER-USERS] Moving Points


> Hi everyone, I'm totally new to MapServer. I've been working with it
> for a little over a month now. I've read the books and worked through
> the tutorials. I'm now working on a demo project and I just can't get
> it all planned out in my head. I'm hopping ya'll can kick me in a good
> direction.
>
> So, the basic function of the map will be to track gps (or something
> similar) data on a map. The data will of course be updated regularly
> by various devices sending some sort of x,y,z location data. That data
> will be plotted on the map, and the zone (city, county, zip or
> something) the device is in will be recorded.
>
> I've searched around for the past few days and have not been able to
> find an example in MapServer. Any help and advice is most welcomed.
>
> Thanks,
> Jay
>
> P.S.
> I don't really know what sort of device will be used to send the data,
> so I just need to fake it.