RE:Overlays, Backgrounds,
Wed, 5 Oct 1994 10:15:51 -0500

In article of 12:35 PM 9/30/94, Alejandro Rivero <rivero@sol.uni writes:

>Is there any method to say to the Html interpreter to put
>a image in the background and/or in the foreground?
>I dont like the ISMAP feature, I would prefer to put the
>map in the background and then add the buttons in standard
>html form. This has two advantages:
>-lynx could read such kind of html pages.
>-bandwinich and CPU usage impreoves, as not connection to the
>CGI or similar is needed to get the jump.
>Any suggestion??
Hmmm, well I have done some similar stuff, although it was not (in the past)
in the scheme of HTML. We provide information server software that lets
people Navigate in a manner quite similar to what you seem to be expressing
and since we are trying to move the basis of our architecture towards HTML,
I have a great interest in getting this functionality out of HTML. Basically
we allow the "page" to consist of images that can be overlayed over each
other (For example, people often use a background/backdrop image and then
several action button images over it). Then the "page" also specifies the
rectangles of any "hot-spots" and the URL for each hot-spot. This has the
advantages you mentioned above, in that an additional query to the origional
server is not necessary and there are no extra decoding tasks needed on the
server side. This would not be a useful way to implement the typical
"weather-map" sort of ISMAP example, but is great for providing graphical
menus for users to navigate. On additional BIG advantage of having the hot
rectangle information passed to the client is that the client can hilight
the selection when it is clicked on, providing critical feedback to the user
(that they clicked where they wanted to).

Alex Hopmann
ResNova Software, Inc.