Re: [orca-list] Misteries of low performance of Orca and distros

[Luke Yelavich <themuso ubuntu com>]

On Wed, Jul 31, 2013 at 12:41:30AM EST, Thomas Ward wrote:
> Alex, just a correction. NVDA is written almost purely in Python as is
> Orca. Since NVDA is written in Python and is relatively responsive I
> think Luke's on the right path in targeting the accessibility
> infrastructure itself for the responce and lag issues with Orca. NVDA
> primarily works by capturing Windows messages and events and
> converting them to spoken output. Orca on the other hand has to go
> through at-spi to find out what is going on with a certain app and we
> get this hourglass design with the apps and desktop on one side and
> Orca on the other with at-spi acting as the middleman. No doubt this
> causes some lag because there is no way to easily poll events and
> system messages like on Windows.
>
> In fact, as I recall the first screen reader for Gnome, Gnopernicus,
> wasn't all that responsive either and it was written in C. That said,
> I have wondered how much of a performence boost we would get if
> someone rewrote Orca in C or C++ and compiled native binaries for
> Linux.

I think this would bring more benefits in memory usage moreso than performance and responsiveness. As for 
DBus itself, I believe there is work ongoing to move the core parts of DBus into the kernel, which may also 
give a big boost to responsiveness.

Luke