Linux Bible 8th Edition
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Linux Bible 8th Edition


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the default (which is 
based on the current system theme). Click the Background Image check box if 
you want to select an Image for the background, and then select an image, such 
as a tile from /usr/share/backgrounds/tiles or another directory.
I usually turn on the AutoHide feature and turn off the Hide buttons. Using AutoHide gives you more desktop space 
to work with. When you move your mouse to the edge where the panel is, the panel pops up\u2014so you don\u2019t need Hide 
buttons.
3D effects with AIGLX
Several different initiatives have made strides in recent years to bring 3D desktop effects 
to Linux. Ubuntu, openSUSE, and Fedora used AIGLX (http://fedoraproject.org
/wiki/RenderingProject/aiglx).
The goal of the Accelerated Indirect GLX project (AIGLX) is to add 3D effects to every-
day desktop systems. It does this by implementing OpenGL (http://opengl.org) 
accelerated effects using the Mesa (http://www.mesa3d.org) open source OpenGL 
implementation. 
Currently, AIGLX supports a limited set of video cards and implements only a few 3D 
effects, but it does offer some insight into the eye candy that is in the works.
If your video card was properly detected and confi gured, you may be able to simply 
turn on the Desktop Effects feature to see the effects that have been implemented so far. 
To turn on Desktop Effects, select System \u27aa Preferences \u27aa Desktop Effects. When the 
Desktop Effects window appears, select Compiz. (If the selection is not available, install 
the compiz package.)
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Chapter 2: Creating the Perfect Linux Desktop
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Enabling Compiz does the following:
 \u25a0 Starts Compiz\u2014Stops the current window manager and starts the Compiz 
window manager.
 \u25a0 Enables the Windows Wobble When Moved effect\u2014With this effect on, when 
you grab the title bar of the window to move it, the window will wobble as it 
moves. Menus and other items that open on the desktop also wobble.
 \u25a0 Enables the Workspaces on a Cube effect\u2014Drag a window from the desktop 
to the right or the left and the desktop will rotate like a cube, with each of your 
desktop workspaces appearing as a side of that cube. Drop the window on 
the workspace where you want it to go. You can also click on the Workspace 
Switcher applet in the bottom panel to rotate the cube to display different 
workspaces.
Other nice desktop effects result from using the Alt+Tab keys to tab among different 
running windows. As you press Alt+Tab, a thumbnail of each window scrolls across the 
screen as the window it represents is highlighted. 
Figure 2.19 shows an example of a Compiz desktop with AIGLX enabled. The fi gure 
illustrates a web browser window being moved from one workspace to another as those 
workspaces rotate on a cube.
FIGURE 2.19
Rotate workspaces on a cube with AIGLX desktop effects enabled.
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Part I: Getting Started
The following are some interesting effects you can get with your 3D AIGLX desktop:
 \u25a0 Spin cube\u2014Hold Ctrl+Alt keys and press the right and left arrow keys. The desk-
top cube spins to each successive workspace (forward or back).
 \u25a0 Slowly rotate cube\u2014Hold the Ctrl+Alt keys, press and hold the left mouse but-
ton, and move the mouse around on the screen. The cube will move slowly with 
the mouse among the workspaces.
 \u25a0 Scale and separate windows\u2014If your desktop is cluttered, hold Ctrl+Alt and 
press the up arrow key. Windows will shrink down and separate on the desktop. 
Still holding Ctrl+Alt, use your arrow keys to highlight the window you want 
and release the keys to have that window come to the surface.
 \u25a0 Tab through windows\u2014Hold the Alt key and press the Tab key. You will see 
reduced versions of all your windows in a strip in the middle of your screen, 
with the current window highlighted in the middle. Still holding the Alt key, 
press Tab or Shift+Tab to move forward or backward through the windows. 
Release the keys when the one you want is highlighted.
 \u25a0 Scale and separate workspaces\u2014Hold Ctrl+Alt and press the down arrow key to 
see reduced images of the workspace shown on a strip. Still holding Ctrl+Alt, use 
the right and left arrow keys to move among the different workspaces. Release 
the keys when the workspace you want is highlighted.
 \u25a0 Send current window to next workspace\u2014Hold Ctrl+Alt+Shift keys together 
and press the left and right arrow keys. The next workspace to the left or right, 
respectively, appears on the current desktop.
 \u25a0 Slide windows around\u2014Press and hold the left mouse button on the window 
title bar, and then press the left, right, up, or down arrow keys to slide the cur-
rent window around on the screen.
If you get tired of wobbling windows and spinning cubes, you can easily turn off 
the AIGLX 3D effects and return to using Metacity as the window manager. Select 
System \u27aa Preferences \u27aa Desktop Effects again and toggle off the Enable Desktop Effects 
button to turn off the feature.
If you have a supported video card, but fi nd that you are not able to turn on the Desktop 
Effects, check that your X server started properly. In particular, make sure that your 
/etc/X11/xorg.conf fi le is properly confi gured. Make sure that dri and glx are 
loaded in the Module section. Also, add an extensions section anywhere in the fi le (typi-
cally at the end of the fi le) that appears as follows:
Section "extensions"
 Option "Composite"
EndSection
Another option is to add the following line to the /etc/X11/xorg.conf fi le in the 
Device section:
Option "XAANoOffscreenPixmaps"
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Chapter 2: Creating the Perfect Linux Desktop
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The XAANoOffscreenPixmaps option will improve performance. Check your 
/var/log/Xorg.log fi le to make sure that DRI and AIGLX features were started 
correctly. The messages in that fi le can help you debug other problems as well.
Summary
The GNOME desktop environment has become the default desktop environment for 
many Linux systems, including Fedora and RHEL. The GNOME 3 desktop (used now in 
Fedora) is a modern, elegant desktop, designed to match the types of interfaces available 
on many of today\u2019s mobile devices. The GNOME 2 desktop (used through RHEL 6) 
provides a more traditional desktop experience.
Besides GNOME desktops, there are other popular and useful desktop environments you 
can try out. The K Desktop Environment (KDE) offers many more bells and whistles 
than GNOME and is used by default in several Linux distributions. Netbooks and live CD 
distributions sometimes use the LXDE or Xfce desktops.
Now that you have a grasp of how to get and use a Linux desktop, it\u2019s time to start 
digging into the more professional administrative interfaces. Chapter 3 introduces you to 
the Linux command-line shell interface.
Exercises
Use these exercises to test your skill in using a GNOME desktop. You can use either a 
GNOME 2.x (Red Hat Enterprise Linux up until RHEL 6.x) or GNOME 3.x (Fedora 16 or 
later or Ubuntu 11.10 or later) desktop. If you are stuck, solutions to the tasks are shown 
for both the GNOME 2 and GNOME 3 desktops in Appendix B.
 1. Obtain a Linux system with either a GNOME 2 or GNOME 3 desktop available. 
Start the system and log in to a GNOME desktop.
 2. Launch the Firefox web browser and go to the GNOME home page 
(http://gnome.org).
 3. Pick a background you like from the GNOME art site (http://art.gnome.org
/backgrounds), download it to your Pictures folder, and select it as your current 
background.
 4. Start a Nautilus File Manager window and move it to the second workspace on 
your desktop. 
 5. Find the image you