Mark center of map?

[Fawcett, David]

Richard, 

I am pretty sure that you want to place a FEATURE on your map.  

Take a look at the documentation here:  http://mapserver.gis.umn.edu/doc44/mapfile-reference.html#feature

The POINTS are in pixels, so based on the image size that you have specified, you can easily calculate the center pixel.  

Instead of placing a label as done below, you want to draw an 'x' or cross.  I don't have a symbol definition handy, but you should be able to find one in the list archives.

Here is a layer from a mapfile that I use to label the top of a map image:

 LAYER
  NAME "MapLabel"
  TYPE ANNOTATION
  STATUS DEFAULT
  TRANSFORM FALSE
  FEATURE
    POINTS 55 10 END # Text in Upper-left
    TEXT "Grandstand - Lower Level"
  END
  CLASS
        LABEL
          COLOR 0 0 0
                  #COLOR 255 255 255
          #OUTLINECOLOR 0 0 0
          TYPE TRUETYPE
          FONT arial
          SIZE 12
          POSITION AUTO
          FORCE TRUE
          OFFSET 1 1
          PARTIALS FALSE
        END # Label
     END  # CLASS
END

-----Original Message-----
From: UMN MapServer Users List [mailto:MAPSERVER-USERS at LISTS.UMN.EDU]On
Behalf Of Richard A. Milewski
Sent: Tuesday, March 15, 2005 4:37 PM
To: MAPSERVER-USERS at LISTS.UMN.EDU
Subject: [UMN_MAPSERVER-USERS] Mark center of map?


Can someone point me at a how-to that describes how to draw on a map?  What
I need to do is plant a big red X at the very center of a map served by
mapserver.  The Symbology reference seems to be all about how to place
symbols at locations defined in a dbf file, but I need to plot this symbol
at the center of whatever extent the user has chosen. The maps are specified
by Lat/Lng, so I know the coordinates but not until they request is actually
sent to MapServer.  Running MapServer 4.4.1 on Linux  (but not Mapscript
...yet).

I can build a script that fetches the image and then places the symbol in
the center of the image with netpbm or image magick, but that seems crude,
and I suspect there is a way to do it inside mapserver, but I haven't found
it yet.

Thanks for the help!

-- Richard