mode etc documentation

[Stephen Davies]

G'day again.

A couple more questions please.

Where are the various mapserv modes documented?
I see references to map, query, scalebar, legend modes but cannot find
details of exactly what each one does and which mapfile entries are used and
whether there are any more modes available.

Where is the code that draws the "box of interest" on the reference map?

What is the relationship between map extent and reference extent? Are they
simply used to scale between the two images?

Thanks in anticipation,
Stephen Davies