What will replace the X Window System?

One of the significant Linux events of the past year was the release of the 25th Fedora with the Gnome 3.22 graphical environment based on the Wayland display server , which is designed to replace the X Window System . But why, after all these years, why did such a need arise?

Recently, the crew of the ISS has moved from Windows to Linux.
- Houston, we have problems. It blows us to Jupiter.
- Are you messing with xorg.conf again?
- Yes. Houston, for the last three days, for some reason, our beards have grown.

Further, it’s about why Linux needs a new graphical environment, at least in 2017, and in a separate post I’ll tell you about Wayland and Mir.

Item X

I am sure that you have already read the Habrapost article about the Linux graphics stack , as well as the page on the wiki and now you can confidently move on. Well, if for now you have left it in bookmarks, let me remind you briefly.

• X Window System - The X window interface system, created in the depths of MIT in the summer of 1984. In the X, a protocol is defined, but reducing everything to a protocol is not justified, although technically it is. The fact is that the protocol itself does not draw windows, and all that today controls graphics on Unix / Linux systems is more than a protocol.
• X11 - The eleventh version of X, which was released in 1987 and in various guises safely lived to our days. In particular, XFree86 has sprung from it, from which then a truly free X.Org Server emerged, with a GPL license, as expected. In this text, X11 will denote a protocol, unlike X, which means its entire set of components, the software as a whole.
• X.Org Server - A free canonical implementation of the server side of X, which is currently the X server for Linux.
  

  (5:50)$ eix -c xorg-server
  [I] x11-base/xorg-server (1.18.4@19.09.2016): X.Org X servers

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• XCB — X protocol C-language Binding, X C. XCB Xlib: X11, , , , . , XCB Xlib, .

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• DIX — Device Independent X, X , .
• DDX — Device Dependent X, X , , .

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• XRender — X - X-, .
• Pixman — , , X.Org, Cairo Firefox.

• Mesa — OpenGL, OpenCL Vulkan API Linux Unix, , . Mesa , OpenGL API, :

  
  
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• DRI — Direct Rendering Infrastructure — X Window System, X server. DRI — Mesa. DRI3, X- , , X . GEM (Graphics Execution Manager), .
• AIGLX — Accelerated Indirect GLX, , Red Hat Fedora Linux X.Org DRI GLX . X- GLX; OpenGL ( Compiz Beryl) .
• GEM/TTM — , , — . GEM , , DRI3.

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Server                           Client
+-------+                        +-----+
Left Button Down
               |
               +----------------> Map menu
Left Button Up                     |
      |                            |
      +-------------------------------> No menu operations visible
                                   |
Map Window <-----------------------+

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X Window System Wayland Mir? , . , . . , , systemd. ?

1. Kernel Recipes 2014 The Linux graphics stack and Nouveau driver
2. X and the future of Linux graphics
3. Linux.conf.au 2013 The real story behind Wayland and X
4. The X Windowing System
5. Explaining X11 for the rest of us
6. Thoughts about DRI.Next