Fix focus follow mouse usability problem

[Simon Thum]

Harald Braumann wrote:
> On Wed, 05 Aug 2009 12:08:54 +0200
> Simon Thum <simon.thum at gmx.de> wrote:
>> There is a distinct advantage the server has, namely, it knows more
>> detail. So it could do a better job than a client/wm. But still that's
>> far from perfect, which I guess is why reading tea leaves has been
>> left to the client.
> 
> I agree completely, but the question is: does the client have all the
> tea leaves to read from? Here's where my knowledge of the technical
> details is not deep enough. From what I understand, the WM would have
> to grab the mouse (probably bad) and then receive all motion events
> (maybe a problem over slow links). 
I don't think so. KWM (which I'm using) has delayed focus, but I'm
unaware how exactly it works. Just tested, it does: It is possible to
cross windows without any focus or visibility change.

Since X motion events include timestamps from nearby the driver, I don't
think the practical difference the server could make would be worth it.
The benefit from knowing whether additional events are queued is
marginal. Mileage may vary with network conditions.

Cheers,

Simon