Re: [Qemu-devel] Status of SDL2 and GTK displays: can we make display modular?

[Gerd Hoffmann <kraxel@redhat.com>]

  Hi,

> With loadable display backend it will be the last bastion
> for many people who are asking for "minimal QEMU for
> servers" which is supposed to not have any X deps.

> I started working on loadable display backend a few
> years ago, but quickly discovered that SDL1 can't be
> loaded dynamically, at least on some platforms where
> it substitutes main() function in order to do some
> initialization (as if there's no support for constructors).
> 
> So now I'm asking again whenever current GTK and SDL2
> supports are complete enough to replace SDL1.

I don't miss any features in sdl2/gtk.

I think gtk should work reasonable well meanwhile as it is the default
and thus used alot.

Not so sure about sdl2.  sdl1 is still the default, so I don't think
there are that many users of it, which increases the chance that there
are unnoticed bugs and regressions lurking ...

Loadable display modules are worth looking into nevertheless.  We need
some kind of interface to register UIs, simliar to blockdevs and
devices.  But we have interesting constrains here:

 * You can have multiple UIs active at the same time (gtk+vnc).
 * That doesn't work for every combination though (no gtk+sdl).
 * There are deps to other stuff such as audio (sdl+spice) and
   display (spice/qxl).

So getting that modeled right isn't that easy and straightforward.

If you wanna have a look nevertheless you are welcome ...

cheers,
  Gerd