[Mapserver-users] WMS BBOX vs. Actual Bounds

[John Gorkos]

Howdy-
  My programming team is up against a hard deadline, and we're stymied.
Basic project is this:  use a WMS mapserver to feed a java applet a base map, 
and then connect (via TCP) to a real-time management system that feeds us 
status of devices across the planet, coded by lat/long and a status code.  
These then get overlayed on top of the base map on a "glass pane" that can be 
changed without redrawing the base.  The result is little winkin', blinkin' 
lights on top of a map that show (in our case) whether or not electricity is 
on in various places across the US.
  The problem is that when we send a BBOX request to the mapserver from the 
java applet, we don't get back a map with the exact coordinates we asked for.  
That's OK, I realize that mapserver gets as close as it can given the image 
size, but I've GOT to know what the real boundaries are so I can overlay my 
status dots on top.  How do I get this information back from the mapserver?
  On a related thread, how does the mapserver decide what the real boundaries 
are, when given when the bounds requested don't match the aspect ratio of the 
returned image?
-- 
John Gorkos
SchlumbergerSema/Atos-Origin