wl_tablet specification draft

Bill Spitzak spitzak at gmail.com
Tue Jul 1 12:32:42 PDT 2014

On 06/30/2014 09:50 PM, Peter Hutterer wrote:

>> Yes this makes sense. Sorry I was confusing it with the X implementation
>> where the Enter event replaced a Move event.
> it does? it's actually one of the ambiguous parts of the X protocol.
> nothing prevents you from sending motion events for the same coordinates
> (indeed, we do so for subpixel motion). So whether you get a motion after an
> enter event is pretty much implementation-dependent. and if you check the
> implementation, we just slot the leave/enter events in before the motion
> event, without ever discarding it.

Actually the problem was with overlapping windows belonging to the same 
client, and this bug still exists in Wayland.

When you move the mouse from one to another the client gets an Exit from 
the first, an Enter on the second, and then a Move (sometimes). The 
result is that after an Exit event I needed to look ahead for enter 
events to see if it entered an a different window belonging to me before 
the Exit can be properly handled, otherwise there may be a blink in the 
highlighting. This is rather annoying.

A fix for Wayland would be to not send the Exit event if the Enter is 
going to the same client. Another method would be to send the Enter 
event first followed by the Exit.

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