lynx-dev Image Map Coordinates and Referer (was: Suggestion)

[David Woolley]

Klaus wrote:
> 
> On Sat, 6 Feb 1999, The Vrana Family wrote:
> 
> > I have a suggestion for a feature that would really help me out.  I enter
> > some contests which require you to enter from an image map on a particular
> > page.  Lynx can only generate a 0,0 coordinate when you "click" on an image

Although such badly written pages are unfortunately quite common, I
think very few Lynx users would have the patience to work out what
coordinates to send, so I think hand editting the URL is the best 
solution.

The correct way of writing such pages these days is to use client side
image maps with correct TITLE(?) attributes, so that a modern text mode
browser gets a menu with no further server interaction.  The fact that
authoring tools will now automatically generate client side maps, means
that the number of totally un-navigable image maps is reducing, although
the remainder still often require guess work to choose the right option.

The original correct way of handling image maps (and still needed for
old text mode browsers, if the ISP permits server side maps) is to detect
0,0 in the server and send a menu, although better style is to include
the menu as text on the main page, which also helps GUI users with images
off.

Most highly graphical sites these days use yet another tactic, which is
to construct a mosaic using borderless tables.  This means each area of
the map is an individual link and can have an indivual ALT=.  Although
IE4 displays the ALT text in too small a font, it is often possible
to click the link before the images have overlaid that text.

I'd suggest that you complain to problem sites that they aren't even
conforming to current GUI only site practice.

> > map.  How about enabling a keyboard command that would let you enter any
> > coordinate the user wanted.  For example, you'd type C (I know that command

There are already too many keyboard commands.

> > enter.  However, if the site requires the "click" to come from the prior
> > page, it won't accept it properly.  It thinks (rightly so) that you're
> > coming from an invalid page - the temporary page with the image map.  I

For client side image maps this has been fixed in current versions of Lynx.

> I regard services that rely on Referer for navigation as pretty much
> broken anyway.

Quite a few people consider Referer evil because, like cookies, it
can be used for constructing click trails, but, unlike cookies, it
can create those trails across sites.  There are a number of pieces
of software that can deliberately suppress Referers for this reason
(e.g. see http://www.junkbusters.com/; also the squid proxy has options
for anonymising requests, and it is possible that ditching Referer is
one of the things these do; I believe Lynx has had the ability to
turn of Referer for a long time).

Of course, the sort of sites mentioned here almost certainly *do* want
to get click trails from you as part of their reason for existence.

At a guess, Referer is being used here to stop external sites linking
to pages other than the official home page.