Re: Texinfo/info: scrolling images (Re: Gtk patch version 3, part 1)

["Robert J. Chassell" <bob@rattlesnake.com>]

   "Robert J. Chassell" <bob@rattlesnake.com> writes:

   > The images are built from plain ASCII characters, of course, but they
   > are there.

Karl Eichwalder <keichwa@gmx.net> responds:

   That's something different.  lilypond authors want to document music
   scores and at times I want to talk about graphical interfaces
   (screenshots).   ASCII representations of such images are a) different
   from the graphical ones and b) highly time consuming to "draw".

Yes, the ASCII representations are often different.  In the case of
music, I think you would want to use the `letter' notation that (if I
remember Lilypond rightly) users type in order to input information so
that Lilypond can create the nicely typeset output that it produces.

The design question is:

    to what should you listen when you should not or cannot view the
    typeset output and do not have or should not use a haptic `feel
    pad'?

And yes, the ASCII representations are highly time consuming to
"draw".  This is a major motivation for you to use a format such as
Texinfo that requires such representations.

Without the motivation, sighted people tend to write only for sighted
readers who are not situationally blind.  This is why LaTeX is not
used as the basis for Texinfo.  We tried to make the change more than
a decade ago.  I made many experiments.  

Yes, you can write a LaTeX `deep-representation' file that produces
good Info `surface-expression' output.  But -- and this is the problem
-- often enough, people do not write such files.  Instead, they use
LaTeX' marvelous typesetting capabilities to create papers that
typeset nicely, and which are impossible for someone reading over a
slow connection or who is listening.  XML and DocBook suffer the same
failing.

   At other places, scrolling images is also very important: I'd like to
   look at a scan and an OCRed text side by side, that's just 1 example.

I agree, that is an important action.  At the same time, please
remember that the blind are major users of OCR.  Please design your
system so that you can listen to a scan and to an OCRed text, as well
as look at them.

   > If you drive a car, you are `situationally blind' and should not look
   > at images in a document, but only listen to it.

   I'm not a car driver anymore ;) 

That may be very good (I don't know your personal situation; but it
would be good for the rest of us if fewer people drove cars).
Unfortunately, many other people do drive.  Others work in factories
where they are supposed to be paying attention to their work.

   Enhance info in a manner that it can hold alternative
   representations of the same contents ...

If you really mean Texinfo, this feature has existed for more than a
decade.  What is wrong with the current feature?

If you mean to enhance the GNU Emacs Info reader to provide highly
typeset images for some viewers -- that is a good idea so long as
sighted, non-driving viewers do not write their documentation so that
it cannot be read by a blind person or over a very slow line (even
though I mostly enjoy a reasonably fast connection, sometimes it is
very, very slow).

Info could be made more like W3M mode in Emacs 21.  W3M is a Web
browsing mode in which you can toggle images on or off.  

-- 
    Robert J. Chassell                         Rattlesnake Enterprises
    http://www.rattlesnake.com                  GnuPG Key ID: 004B4AC8
    http://www.teak.cc                                     bob@gnu.org