Accessibility for users with disabilities

[Matt Campbell]

Hello from a GNUstep newbie,

First a little introduction:  I've been learning Cocoa for a project at 
my job, and I decided to use GNUstep Renaissance for the UI, because I 
find it much easier than drag-and-drop tools like Interface Builder.  So 
now I'm interested in playing with GNUstep itself; I think it would make 
an excellent cross-platform GUI toolkit.  But I've noticed one major 
missing feature, which I wonder if anyone else has considered or started 
to work on:  accessibility for users with disabilities, particularly 
users who are blind or visually impaired.

As I see it, there are three major steps to implementing accessibility:

1.  Add a definition of the NSAccessibility protocol and its related 
constants from Cocoa.

2.  Implement NSAccessibility in the standard controls (or more 
accurately, in their cells).  Strive to mimic the NSAccessibility 
implementations of the respective cells in Cocoa.

3.  Implement bridges from NSAccessibility to the native accessibility 
APIs on the supported platforms.  On Windows, the relevant APIs are 
Microsoft Active Accessibility and IAccessible2.  For X-based platforms, 
I believe the relevant API is AT-SPI, though my knowledge of 
accessibility in the modern X-based desktops is a bit out of date.  This 
will probably be the most complicated part; MSAA in particular is 
notoriously hard to get right.

Task 1 should be pretty straightforward, if tedious.  Tasks 2 and 3 are 
big and should probably happen in parallel.

I don't currently have much time to contribute to such an effort, but I 
can at least provide pointers in the right direction, particularly for 
the MSAA/IA2 bridge.  In any case, I thought I should at least point out 
the need for this, particularly since accessibility isn't mentioned in 
the development roadmap.

Question:  I've perused some of the Cocoa header files, including 
NSAccessibility.h.  Does that disqualify me from doing a clean-room 
implementation for GNUstep?

Matt