OpenGL Becoming a Requirement For the Linux Desktop

An anonymous reader writes "Modern Linux desktops like Ubuntu's Unity and the GNOME Shell have placed a requirement on OpenGL 2.0+ support for handling their compositing window managers and desktop effects. Wayland's Weston also needs OpenGL ES 2.0 support. Now with modern Linux distributions like Ubuntu 12.10, rather than falling back to a 2D unaccelerated desktop if you don't have a sufficient GPU or graphics driver, users are being forced to run LLVMpipe as a CPU-based software rasterizer. LLVMpipe works fine if you are on a new PC with a fast x86-64 CPU, but the OpenGL-based Linux desktops are causing growing pains for ARM hardware, virtual machines, servers, multi-seat computers, and of course all older hardware. LLVMpipe is a Mesa Gallium3D driver that uses LLVM for run-time code generation as an attempt at accelerating graphics faster on the CPU. So much for Linux being good for old computers?" The KMS based graphics stack is already effectively unusable on AGP systems (if you have SMP + AGP, there are race conditions somewhere leading to really hard crashes that appeared a couple of years ago and dozens of years old open bugs with no resolution other than "use PCI mode" which cuts bus bandwidth by 4 or 8 times, and still doesn't work with SMP), but for those with older PCIe/IGP systems you could always runs Window Maker, Sawfish, Enlightenment, Open Box, or one of many other window managers without a compositor. Of course then you lose compositing, and there aren't any usable external compositors for some reason. The flipside to this is that moving to OpenGL as the primary interface to the GPU means one fewer driver that has to be written, and will probably lead to an overall improved experience for those with supported hardware given the limited resources Free Software drivers authors have.

Comments

Fluxbox

[Hatta]

Still no OpenGL required for Fluxbox. Still snappy on old hardware too.

Re:Fluxbox

[Windwraith]

Let's keep people educated. KDE 4.x (Kwin) doesn't require GL either, it's completely optional and can be disabled, "live", via a keyboard shortcut or setting an automatic window property (like launching a game > disable compositing".

It's important that people knows KDE doesn't require GL to run, so they:
A) Keep maintaining it.
B) Others see it as an example of how to do things right.

Re:Dear OP

[Anonymous Coward]

you are out of date. Unity 2d is now dropped.

alt+shift+F12

[Anonymous Coward]

KDE (Kwin) has one of the most advanced compositing window managers around. You can toggle compositive off with alt+shift+F12 and go back to a 2D desktop. If it detects that it cannot run with compositing due to hardware limitations, it will do that by default, or you can configure it not to if you just don't like that.

There is no requirement for OpenGL in any reasonable window manager.

Re:And?

[troon]

You'd be surprised how many people run older hardware. I don't give a damn about gaming; so all three desktops and one of the two laptops in my house are old 32-bit machines (Athlons, Pentium 4 3.06GHz HT, Celeron in the lappy). They run apps just as fast as when they were new state-of-the-art machines - it seems daft that it's the window management that's forcing me to look for leaner distros. I'm certainly not going to spend money upgrading hardware to have prettier window decorations and physics.

Re:KDE?

[brennanw]

KDE doesn't require a compositor, and you can toggle compositing on and off pretty easily if you want.

Re:Dear OP

[Windwraith]

Too many comments forget Kwin. Which kind of shows nobody really uses KDE4, apparently, because it's a killer feature nobody knows about: It doesn't require GL and can enable and disable it on the fly without losing anything you are doing at the time. Even with automated rules!

Re:openbox+xcompmgr

[Narishma]

Don't lump KDE in with the others. It's just Gnome and Unity doing this.