visual impairment focused design

[Michal Koudelka <koudelka michal gmail com>]

Hi,

Firs  of all, I apologize if this question does not belong to this group or if I am asking for something others consider as trivial. I have a lot of experience with web programming and I also did some desktop stuff for OS X, but both the a11y topic is very new to me.

I need to make an application which is not just supposed to be accessible but designed specifically for people with visual impairment so it should rely heavily on using speech synthesiser and braille refreshable display.

I am able to control braille display by brltty and as far as I saw, Orca can use brltty as well. But there is one issue I am facing at this moment. It's possible to somehow override UI widgets and specify what should be only displayed on Braille display only and what should be process by speech synthesiser?

Is there a clear solution to this? I will be very grateful if somebody can help directing me, which api or which object I should look on.

Thank you for any help,

Michael