CGI or Mapscript

[Steve Lime]

He's refering to the Mapserv object. It may have been called something
different earlier
in its life.

Yes, the extent can change and there are two reasons:

1) the user has explicitly triggered something that computes a new
scale (e.g. a zoom, pan or
box zoom)

2) that computed extent must be adjusted to the map size (imagine
dragging a tall, thin zoom
box)

Depending on where you put alerts in mapserv.js you may see changes
before or after these
cases. I've not implemented accessor functions everywhere so you need
to access the object
members directly. For example, the extent member contains the extent of
the currently
displayed map. 

When you say your zoombox doesn't work. Is that a dBox zoombox or your
own code? If I
remember back to the days when I started dBox an error like that has to
do with the order
of coordinates handed to whatever is drawing the rectangle. Perhaps it
is expecting
minx. miny, maxx, maxy and your sending the reverse? Just a thought.

Steve

>>> John Smith <jayzee.smith at GMAIL.COM> 10/31/2006 4:22:23 PM >>>
map object??

i've popped up using alert(this.extent) but depending on where you
insert
that alert() in mapserv.js its value changes! i've looked through
http://maps.dnr.state.mn.us/tools/dbox/docs/jsdocs/ but can't get the
values
contained in the map object. is there a dbox guru lurking on this list
;)?

i've also tried making my own zoombox but can't get the zoombox to
follow
the cursor if the cursor is dragged from right-bottom to left-top in
the
negative direction. any help with that?
i admit this is not strictly a mapserver question but then again
there's no
dbox list.
jzs
On 10/18/06, Richard Greenwood <richard.greenwood at gmail.com> wrote:

> On 10/18/06, John Smith <jayzee.smith at gmail.com> wrote:
> > thks. yeah dbox is cool but i got another question- i'm trying to
output
> > [imgext] and other cgi variables from dbox. how do i grab them?
i'd
> really
> > want to use the backward and forward browser buttons. i think
navigation
> is
> > way cooler that way.
>
> When you reload a whole page, you can get mapserver (on the server)
to
> provide values for variables in [...] but with dBox you are usually
> not reloading the whole page from the server, you are usually only
> requesting a new map image. So the new extent needs to be calculated
> on the client (the browser).   Thanks to mapserv.js, this is no
harder
> than requesting the new values from the server, and a lot more
> elegant. The extent, scale, size, etc. are contained in the map
> object, and are updated each time you make a new map request.
>
> But by not relaoding the whole page, the browser's back and forward
> buttons don't do what you would expect, and you can not book mark
the
> URL. There are a couple thing you might try: you could maintain a
> "history" stack and add your own back & forward buttons to your user
> interface (ArcIMS, MapBuilder, and many others do this), or you
could
> try pushing the current map parameters into the browser's history.
> Don't know what problems you'd encounter, but that always seemed
more
> elegant to me. I just haven't gotten around to trying to implemet
it.
>
> Rich
>
> --
> Richard Greenwood
> richard.greenwood at gmail.com 
> www.greenwoodmap.com