Re: [g-a-devel] No module anymore & perfect zoom feature

[Samuel Thibault <samuel thibault ens-lyon org>]

[Re-sending without the attached pictures, too big for the list]

Hello,

Emmanuele Bassi, on jeu. 01 mars 2018 14:42:27 +0700, wrote:
> On 26 February 2018 at 17:49, Samuel Thibault
> <samuel thibault ens-lyon org> wrote:
> > Hello,
> >
> > So, I also saw the removal of generic modules.
> >
> > Unfortunately we currently need it for implementing perfect zoom feature
> > :)
>
> I don't know what a "perfect zoom feature" is —

Please compare the two examples on

https://people.debian.org/~sthibault/zoom-gimp.png
https://people.debian.org/~sthibault/zoom-perfect.png

zoom-gimp.png is the kind of zoom you can get with state-of-the-art
zooming heuristics. zoom-perfect.png is simply obtained by getting gtk
to redraw the window into a bigger pixmap.

> but zooming on a window should be part of the display server.

The display server can not invent information, at best it could
achieve the zoom-gimp.png result, which is really not enough for
visually-impaired people. Here I have only magnified a couple of times,
people quite often request for 10x-30x magnification.

Also, the control on zooming should really not implemented in the
server. Usually you'll also want color inversion or mangling, adding
position hints etc. I don't think freedesktop people will be happy to
see that added to the display server, so an external solution is needed,
currently implemented in Compiz (but lacking access to re-rendering on a
bigger pixmap).

> Having said that, we do have a magnifier inside GTK, used by the
> Inspector. We could make that feature public, and improve it.

Interesting.  Having mentioned adding the feature to AT-SPI, I'm
however interested in putting the interface there, so that not only GTK
application can benefit from it, but also Qt, etc. and GTK can just plug
its support into AT-SPI.

> We definitely do not want to let people inject code into running applications.

Ok :)

Samuel