Help with GMAP sample application

[LITTLE Nelson]

Hi everyone,

I am looking at the sample PHP MapScript example 'GMAP' (as referenced
at the bottom of
http://mapserver.gis.umn.edu/docs/howto/phpmapscript-byexample/view).
The source file 'gmap75.inc.php' references the following HTML FORM
attributes:

KEYMAP_x
KEYMAP_y
mainmap_x
mainmap_y
redraw_x

But I can't for the life of me see where those variables are set
anywhere in the code. They certainly don't exist in 'gmap75.phtml' or
'gmap75.inc.php'. Can anyone offer some help, perhaps there is a source
file missing from the download?

Thanks,
Nelson 

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