The modern trend is for operating systems to incorporate flashy graphical effects into ordinary desktop functions. For example, when windows are minimized in Windows Vista, they physically shrink and fade down to the taskbar.
Under Mac OS X, program windows appear to be “poured” into the Dock when minimized. In Windows Vista, when you press Alt+Tab to switch through open programs, the program windows are previewed
vertically in a graphical arrangement, and you can flick through them, rather like searching
through a card index. These effects are achieved using the 3D processing power of the computer’s graphics card, even though the effects aren’t necessarily 3D in nature.
■Note On a technical level, the technique is known as compositing. What you see on the screen is first drawn in the graphics card memory and then transferred to the screen, rather than everything simply being drawn directly onto the screen.
Ubuntu includes similar desktop visual effects, courtesy of a system called Compiz Fusion (www.compiz-fusion.org). However, all desktop visual effect systems have a couple requirements, and these apply to Ubuntu as well:
• For desktop effects to work, your graphics card (or motherboard graphics chipset)
must be comparatively recent. Examples include the ATI Radeon, nVidia GeForce,
and Intel GMA product lines. Most graphics cards manufactured within the last two
or three years with a graphics processing unit (GPU) should be adequate, and very
recent models definitely will work.
• The correct graphics drivers must be installed. Some of Ubuntu’s built-in graphics
drivers lack the necessary 3D functionality to support desktop effects. Currently,
Intel GMA and some ATI Radeon graphics cards are supported by default because Intel
and ATI provide open-source 3D-capable drivers. For other hardware, including
nVidia cards, you will need to manually install a proprietary driver, which is not
difficult to do.
■Note You only need to install the proprietary driver if you wish to utilize desktop visual effects. Ubuntu includes a default 2D graphics driver that provides excellent functionality for everyday desktop use.
Some proprietary 3D graphics drivers are provided under Ubuntu, but only if open-source equivalents are missing. It is hoped that open-source drivers will one day replace the need for proprietary drivers.
So do you actually need to install new drivers? If you find that desktop effects are working,
then the correct drivers are already installed. A good way to test this is to hold down Ctrl+Alt
and then tap the left or right arrow key. This will switch to the next virtual desktop. If the
entire desktop physically slides out of the way, then desktop effects are activated. If the
desktop remains static and a small dialog box appears in the center of the screen to let you
choose a virtual desktop, then desktop effects are not activated.
A utility called Hardware Drivers lets you manage proprietary drivers for your graphics card. This should appear in the notification area automatically immediately after installation if your hardware requires proprietary drivers.
Follow these instructions to activate the proprietary graphics driver:
1. Click the Hardware Drivers icon to run the Hardware Drivers program. If it’s not
visible, click System ➤ Administration ➤ Hardware Drivers.
2. Supply your password in the authorization dialog box and click OK.
3. In the Hardware Drivers window, check the Enabled box beside your graphics card
device driver.
4. A dialog box appears, asking you to confirm that you want to enable the driver. It
explains that enabling the driver enables visual effects on your desktop. Click the
Enable button.
5. The Summary dialog box appears to tell you what new software will be installed.
Click the Apply button.
6. The driver will be downloaded and installed. Then the Changes Applied dialog box
will appear to tell you that the changes are completed. Click the Close button.
7. In the Hardware Drivers window, click the Close button.
8. You need to restart the computer so that Ubuntu will use the new driver. Select
System ➤ Quit, and then click Restart.
Once the new graphics driver is installed, desktop visual effects should start working immediately. If you experience seemingly random system-wide crashes or freezing after installing a 3D graphics driver, consider reverting to your old setup by using the Hardware Drivers program
(System ➤ Administration ➤ Hardware Drivers) to disable the new driver.Unfortunately, in a small minority of cases, the proprietary driver can prove buggy.
■Tip On one of our test PCs, containing an nVidia GeForce 6600 graphics card, the Hardware Drivers program didn’t install the new driver as it should. This is probably a bug that might be fixed by the time you read this, but we got around it by manually installing the driver. The procedure is to open the Synaptic Package Manager (System ➤ Administration ➤ Synaptic Package Manager), search for the nvidia-glx-new package, and mark it for installation. Then reboot. When the system is up and running again, start Hard-ware Drivers, and once again put a check in the box alongside the graphics driver. If there’s already a check there, remove it and put it in again. Upon a second reboot, desktop visual effects should become operational.
Two modes of operation are available for desktop visual effects: Normal and Extra.Normal is the default and provides a good subset of the available effects: menus fade into view, program windows shrink when minimized, and so on. Extra provides a lot more effects, some of them rather extreme, such as wobbling when you click and move a window, and windows appearing to explode to the corners of the screen when maximized. To switch between the two settings, right-click the desktop, select Change Desktop Background,and then click the Visual Effects tab in the dialog box that appears.
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