Re: Touch events

[Alan Third <alan@idiocy.org>]

On Wed, Jun 28, 2017 at 08:14:33AM -0700, raman wrote:
> Also it would be nice to think ahead and build something that works on
> tablets and phones, AKA keyboardless devices. 
> 
> Emacs on those devices in turn might well offer an interesting
> experimental platform for testing out different touch input mechanisms
> ---  given Emacs' long history of smart completion across different contexts.

I’ve been looking into the Xorg side of touch events and it doesn’t
have built‐in gesture support, so I think I’ll have to code that
myself. I was thinking it could maybe be worth passing the touch
events up to lisp and doing gesture recognition in it. That would, I
think, also allow us to handle touch screen devices better as we
wouldn’t have to rely on mouse emulation.

The downside is that my lisp skills are woeful and on platforms where
touch gestures ARE available, we might end up with differing behaviour
from native apps.

The best of both worlds would be if we’re able to fire off input
events from within lisp code, which would let us transparently emulate
system touch gestures where they’re not available, while still having
access to all touch events. I don’t know if that’s possible.

The other option, I suppose, is to pass gesture events from C, and
also pass the basic touch events to lisp. That might be easier.

I need to build an Xorg dev system and try digging into this stuff.
-- 
Alan Third