Re: Gnome Magnifier

[Bill Haneman <Bill Haneman Sun COM>]

Hi Shawn:

> I am having a problem with Gnome Magnifier.  I have it installed from RPM on
> Fedora Core 1.
>  
What application do you mean?  Do you mean 'gnopernicus', i.e. "screen 
reader and magnifier" from
the applications->accessibility menu?  Or are you running gnome-mag's 
"magnifier" binary
from the command-line, in standalone mode?

> I am having problems getting it to not magnify the magnified part of the
> screen.  
>  
In order to see fullscreen magnification, you must have two 
"framebuffers."  In
"half screen" mode, you cannot use the whole screen since some area must 
be available
for applications to draw into.

You can do this if you have two separate physical framebuffers (hardware 
and/or memory dedicated to
displaying images) or if you have a virtual framebuffer 
(work-in-progress, not generally available yet).
Many modern graphics cards can be configured to support two simultaneous 
framebuffers, but it
is not particularly easy to do.  But if you have two graphics cards you 
will have two
framebuffers.  This is like having two "heads" (physical displays) 
except that one framebuffer
is not connected to a monitor.

In order to see fullscreen magnification, you configure the magnifier 
(either the standalone binary
or gnopernicus) to use one 'screen' as the "source display" and the 
other as the "target display".
The displays/screens use a numbering system (this is an XWindows 
convention) thus:
<hostname>:<server_number>.<screen_number>
so if you have two screens on your xserver, they might be called

myhost:0.0 and myhost:0.1

note that if you are using your local host's X Server (which is the 
usual case), you need
not specify the hostname.

At this time, gnopernicus makes no attempt to prevent the magnifier's 
source and target
areas from overlapping, which does result in magnification of the 
already-magnified
area if, for instance, your 'source' mouse pointer moves into the 
magnified region itself.

Configuring your system to use two framebuffers/"X screens" will give 
you a way
around this problem.

regards

Bill

> Two questions:
>
>
>
> 1. How do I get it to use the whole screen for the magnified image?
>
>
>
> 2. How do I get it not to magnify the already magnified image?
>
>
>
> Shawn Djernes
>