GNOME 3
Summary
Include GNOME 3
Owner
- Desktop SIG
- Email: fedora-desktop-list@redhat.com
Current status
- Targeted release: Fedora 15
- Last updated: 2010-11-15
- Percentage of completion: 60%
GNOME has been mostly updated to 2.91.2 in rawhide. dconf, gtk3 and yelp-xsl are in rawhide. The dbus a11y stack is now the default. gtk3 modules have been added for at-spi2-atk, PackageKit and gtk3-engines. The GNOME 3 visual appearance is being defined in the new theme packages gnome-icon-theme-symbolic, gnome-themes-standard and gtk-theme-engine-clearlooks.
Detailed Description
GNOME 3 is the next major version of the GNOME desktop. After many years of a largely unchanged GNOME 2.x experience, GNOME 3 brings a fresh look and feel with gnome-shell. There are also many changes under the surfaces, like the move from CORBA-based technologies such as GConf, Bonobo and at-spi to dbus-based successors.
The user experience of GNOME 3 is largely defined by gnome-shell, which is a compositing window manager and desktop shell. It replaces the GNOME 2 desktop shell, which consisted of metacity, gnome-panel, notification-daemon and nautilus.
Apart from pure window management, gnome-shell provides the top bar on the screen, which hosts the 'system status' area in the top right, a clock in the center, and a hot corner that switches to the so-called 'overview' mode, which provides easy access to applications and windows (and in the future, documents).
In gnome-shell, notifications are displayed in the 'messaging area' which is an automatically hiding bar at the bottom of the screen. This is also where integrate chat functionality is provided.
Benefit to Fedora
Fedora stays in sync with upstream, and gains a new user experience. Some long-standing problems with the CORBA-based accessibility stack will hopefully be solved as a side-effect of the move to D-Bus
Scope
- Package new components
- Build packages which provide gtk modules for gtk2 and gtk3 (tracked [upstream]):
- librsvg2 (Done)
- gtk2-engines [gtk3-engines review] (Done)
- ibus-gtk [bug] (Done)
- at-spi2-atk (Done)
- PackageKit-gtk-module (Done)
- Make GTK-using libraries parallel-installable, or port them to GTK3, or drop their GTK dependency:
- libnotify (done, dependency now implicit)
- gnome-desktop (done, parallel-installable gnome-desktop3)
- libunique ([done], parallel-installable libunique3)
- gtksourceview ([done], parallel-installable gtksourceview3)
- webkitgtk ([done], parallel-installable webkitgtk3)
- vte ([bug])
- libwnck ([bug])
- libmetacity-private ([bug])
- clutter-gtk
- libchamplain-gtk
- gtkimageview
- cheese-gtk
- polkit-gtk
- Switch to the dbus-based accessibility stack (Done)
- Implement data migration for applications that are ported from GConf2 to dconf
- done for evince
- done for gedit
- done for brasero
- done for gnome-bluetooth
- done for nautilus-sendto
- done for gnome-color-manager
- done for gnome-packagekit
- done for gnome-power-manager
- Implement fallback from the shell to 'classical GNOME' for unsupported hardware
- All system status indicators must use symbolic icons, others are optional
- power (Done)
- updates (Done)
- network
- keyboard
- sound
- bluetooth
- Make sure applications keep working and don't run into mixed linkage against both gtk2 and gtk3 via gtk-using libraries. Currently known problems:
- rhythmbox (uses gtk2, but needs libbrasero-burn/media and gnome-media-profiles, which have moved to gtk3)
- gthumb (uses gtk2, but needs libbrasero-burn which has moved to gtk3)
- solang (uses gtk2, but needs libbrasero-burn/media which has moved to gtk3)
- gnomeradio, nautilus-sound-converter also use gnome-media-profiles
- Current mixed linkage problems that need to be addressed:
- gnome-volume-control-applet
How To Test
How to test the accessibility stack:
- . Make sure accessibility support is turned on
- . Install at-spi2-core, at-spi2-atk, pyatspi
- . Set the GConf key /desktop/gnome/interface/at-spi-corba to false
- . Log in again
- . Verify that at-spi-registry is not running
- . Start orca
- . Verify that at-spi-registryd2 has been activated
- . Verify that speech support in orca works as it does with the old stack
Repeat these steps with other accessibility technologies
How to test fallback:
- . Use a system with supported graphics card
- . Log in to a GNOME session
- . Verify that you end up with gnome-shell
- . Switch to a system with a graphics card on which we don't have 3d support (e.g. a VM)
- . Log in to a GNOME session again
- . Verify that you end up with the 'classic GNOME' desktop
User Experience
The user experience (on supported hardware) will be defined by gnome-shell.
Accessibility tools will work as well as (or hopefully better than) they used to. The onscreen keyboard will no longer be gok, but caribou, which may offer a slightly different user experience.
Dependencies
- gnome-shell uses clutter, which relies on 3D hardware and drivers. In F13, the shell is known to work ok with Intel and ATI graphics, and work somewhat with the nouveau driver for NVidia graphics. For F14, we want the shell to work well with all three of
- xorg-x11-drv-ati
- xorg-x11-drv-intel
- xorg-x11-drv-nouveau
- Any packages that install modules for gtk2 (such as image loaders, input methods or theme engines) need to do extra work to make their functionality available to gtk3 too
Contingency Plan
If gnome-shell is not complete or stable enough, keep it experimental and stay with 'classical GNOME' as the default. Users will still be able to try the shell manually, just like in F12 and F13.
If the dbus-based accessibility stack is not sufficiently functional, we switch back to the CORBA-based stack.
Applications can be ported from GConf to dconf and from gtk2 to gtk3 one-by-one, so if the porting work is not complete (and it is very unlikely that it will be), we can just ship with some applications using the new technology, while others still use the old one.
Documentation
- http://www.linuxfoundation.org/collaborate/workgroups/accessibility/atk/at-spi/at-spi_on_d-bus
- http://live.gnome.org/GnomeShell/
Release Notes
- Fedora 14 includes GNOME3. It brings the first major overhaul of the GNOME user experience in 10 years.