Clients reading their surface position on screen

[Gerry Boland]

On 12/08/14 03:33, Christopher James Halse Rogers wrote:
> On Tue, Aug 12, 2014 at 3:09 AM, Gerry Boland
> <gerry.boland at canonical.com> wrote:
> > Personally I don't like the idea of clients being able to ask for their
> > on-screen position - really there's only a couple of valid use-cases,
> > which are very special. All apps don't need this.
> >
> > Sure the other side of the argument is "what is the harm?" - but IMO it
> > could offer that tiny bit more information to help a malicious app
> > misbehave - so I'd rather play it safe.
>
> My primacy concern is not about malicious apps. I'm concerned about apps
> relying on data that the compositor may not be able to provide. It's
> entirely possible that there *isn't* a correct answer for “where is my
> surface on screen”, and any attempt to use such information will result
> in incorrect behaviour.
>
> If we expose this to Qt it'll appear to work (almost) all the time under
> Unity8, apps will find some reason to depend on this working, and then
> when we - or someone else - wants to do something funky we'll find that
> we can't because it breaks clients.
>
This is what is happening right now with X11 though and there's not been any complaints. Since it's really only AP which needs this, it's AP's fault if they do something funky and it breaks.
-G