The Story of Ubuntu's Mir Abstraction Layer (MirAL)

[phoronix]

Phoronix: The Story of Ubuntu's Mir Abstraction Layer (MirAL)

More and more recently we have found ourselves talking about Mir's abstraction layer, MirAL. It turns out that this set of interfaces to Mir has advanced from being a hobby project by a Canonical developer to now being a formal project within the organization and more of Unity 8 is making use of MirAL's API/ABI...

http://www.phoronix.com/scan.php?page=news_item&px=Ubuntu-MirAL-Story

[sarmad]

I am confused. Isn't MirAL what Wayland has been all about from the very beginning, which is what Canonical was complaining about to begin with?

[shmerl]

It's prime time for Canonical to stop fooling around and wasting everyone's time. They should turn Mir into Wayland compositor.

[pracedru]

It's prime time for Canonical to stop fooling around and wasting everyone's time. They should turn Mir into Wayland compositor.

Yeah.. And that shouldn't even be that difficult now with so many references for implementation. Elementary, KDE/Plasma, GTK3/Gnome, QTWayland, Weston, etc.

[eltomito]

"It's prime time for Canonical to stop fooling around and wasting everyone's time. They should turn Mir into Wayland compositor."

That sounds reasonable! Does anybody understand the intrinsics enough to refute?

[labyrinth153]

Yes. They suffer from delusions of grandeur and not invented here syndrome. Ubuntu needs to sell to red hat or suse and stop wasting our time.

[bregma]

I am confused. Isn't MirAL what Wayland has been all about from the very beginning, which is what Canonical was complaining about to begin with?

No, Wayland is not and has never been an API for a window managers to talk to a compositing display server. Wayland is a wire protocol for communication between a client program and a compensating display server that contains a window manager. They are in fact opposites.

[sarmad]

No, Wayland is not and has never been an API for a window managers to talk to a compositing display server. Wayland is a wire protocol for communication between a client program and a compensating display server that contains a window manager. They are in fact opposites.

So what's Wayland's equivalent in Mir world? How do client programs communicate with Mir?

[bregma]

"It's prime time for Canonical to stop fooling around and wasting everyone's time. They should turn Mir into Wayland compositor."

That sounds reasonable! Does anybody understand the intrinsics enough to refute?

Yes,

(1) There is really no advantage to using the Wayland wire protocol with Mir display server stack. Mir already has a wire protocol. It's probably possible to use a subset of the Wayland wire protocol, and add some extensions, but then you would have a non-standard, incompatible version of the protocol that would take another year to deliver for what net benefit at what net cost?

(2) Wayland is not a compositor. Wayland is a wire protocol. You could not turn Mir into a Wayland compositor, because Wayland is not a compoitor.

I'd like to turn this line of reasoning around, and ask this. If Elementary, KDE/Plasma, GTK3/Gnome, Weston, etc. all different compositing display servers not invented here but not a waste of time, why is Mir considered a waste of time? Extraordinary claims require extraordinary evidence. Let's see yours, and please start with numbers and cite your references.

[bregma]

So what's Wayland's equivalent in Mir world? How do client programs communicate with Mir?

How do clients communicate with a Wayland compositor in the real world? Through client libraries, of course. Did you think Wayland was using dark magic, or maybe it was compatible with X11?

Qt, GTK+, libSDL1.2, libSDL2, GLFW, and a number of other toolkits have been ported to libmirclient, just like they have libwayland-client. That covers the vast majority of software you're going to see on your desktop that doesn't use X11 directly (and those that do work equally poorly under a Wayland compositor). Porting modern toolkits is not that big of a job, and those older toolkits (and apps) that assume Linux==X11 are broken for everyone, not just Mir.

An application developer could choose to write software exclusively for Wayland. Or X11. Or Mac OS X. Or Mircrosoft Windows. Some have. The successful ones don't.