Re: [9fans] How to go about doing screen reading

[Chris Brannon <cmbrannon@cox.net>]

pietro10@mac.com (Pietro Gagliardi) writes:

> In pseudocode:
>
> 	when mouse has not been moved for at least 1 second
> 		find cursor position
> 		if cursor has moved
*SNIP*
> Any technical problems with this approach?

I think there is an easier way to do screen reading within Acme.  Here's
a quote from the Acme paper:

<quote>
The last file, event, is the most unusual. A program reading a
window's eventfile is notified of all changes to the text of the
window, and is asked to interpret all middle- and right-button
actions. The data passed to the program is fixed-format and reports
the source of the action (keyboard, mouse, external program, etc.),
its location (what was pointed at or modified), and its nature
(change, search, execution, etc.). This message, for example,

MI15 19 0 4 time

reports that actions of the mouse (M) inserted in the body (capital
I) the 4 characters of timeat character positions 15 through 19;
the zero is a flag word. Programs may apply their own
interpretations of searching and execution, or may simply reflect
the events back to Acme, by writing them back to the eventfile, to
have the default interpretation applied. Some examples of these
ideas in action are presented below.
</quote>

A screenreader can obtain information about changes to the state of the
system by reading the event file.  Do other parts of the window system
provide this sort of interface?

-- Chris