Linux.Desktop.Hacks [Electronic resources] نسخه متنی

Hack 23. Spice Up Your Desktop with Creative Mouse Cursors

Replace the boring default mouse pointer,
resize cursor, wait cursor, and the rest with colorful custom
animated cursors.

Microsoft Windows lets
you
change cursor themes easily. Linux doesn't make it
quite as easy (although the KDE desktop environment comes close).
This hack explores how to check if your distribution of Linux
supports cursor themes, how to find, download, and install new cursor
themes, and how to set up your desktop to use them. A wide variety of
custom cursor themes are available, ranging from the subtle (cursors
decorated with a red dot) to the outrageous (a Tux penguin grabbing
windows to resize them!).

4.3.1. Does Your Desktop Support Cursor Themes?

You need XFree86 4.3 or
later
or Xorg (a fork of the XFree86 project) for custom cursors to work.
All recently released Linux distributions include one or the other,
so it is unlikely that your Linux desktop cannot support custom
cursors, but you need to be sure. Type this command to see which
version of X you have installed:

# X -version

If your Linux distribution installed XFree86, all you have to do is
make sure the version is 4.3 or higher. For example, look for a
string something like the following in the output of the X
-version command:

XFree86 Version 4.3.0 (or higher)

If your Linux distribution is using the Xorg branch of X11, you
should see something like this in the output:

X Protocol Version 11, Revision 0, Release 6.7 (or higher)

If you see anything like either of these strings, it means your
version of X supports custom cursor themes.

4.3.2. What Themes Are Available by Default?

Unfortunately, Linux distributions
vary
considerably as to where they store the default cursor themes. If the
documentation for your Linux distribution doesn't
tell you where to find these themes, you can use a trick to find out
where your particular distribution looks for cursor themes.
Generally, the file you want to examine is
/usr/X11R6/lib/X11/config/Imake.tmpl. Check to
see if the file exists with the ls command:

# ls /usr/X11R6/lib/X11/config/Imake.tmpl

If the response is "No such file or
directory," you might be able to find the file with
the following command:

# locate Imake.tmpl

If this file does not exist on your system, you're
going to have to find another way to locate where your distribution
stores globally available cursor themes. A Google search or browsing
online forums specific to your distribution are good places to start.

If this file does exist on your system, this command should help you
determine the default locations where your distribution stores cursor
themes:

$ grep XcursorPath /usr/X11R6/lib/X11/config/Imake.tmpl
#  ifndef XcursorPath
#   define XcursorPath "~/.cursors:~/.icons:/usr/local/share/cursors/xorg-x11:/usr/
share/cursors/xorg-x11:/usr/share/pixmaps/xorg-x11"
#ifndef XcursorPath
# define XcursorPath Concat(~/.cursors:~/.icons:/usr/local/share/cursors/xorg-x11:/
usr/share/cursors/xorg-x11:/usr/share/pixmaps/xorg-x11:,IconDir)
XCURSORPATH = XcursorPath         /* Xcursor cursors path */

The useful information is the first line that includes
define XcursorPath. Notice that this particular
distribution (Gentoo) defines the XcursorPath to
search the following directories:

~/.cursors
~/.icons
/usr/local/share/cursors/xorg-x11
/usr/share/cursors/xorg-x11
/usr/share/pixmaps/xorg-x11

Take note of the order in which your system searches for cursor themes. It looks first in your home directory, then it searches directories available to everyone. To install a new theme for your personal use only (see later for instructions), you install it in your home directory (under ~/.cursors or ~/.icons). To install a new theme everyone can use, install it in one of the remaining directories in the list.

Check all these directories to see if any theme files exist. The
first two directories are below your home directory, and few, if any,
distributions install alternate cursor themes there by default. So,
you're more likely to find alternate themes in one
of the last three directories in the list. Because
I'm "in the know"
about Gentoo and therefore have an unfair advantage, I would check
the /usr/share/cursors/xorg-x11 path first:

# ls /usr/share/cursors/xorg-x11
Blue  Silver     default  gentoo-blue    handhelds  whiteglass
Gold  blueglass  gentoo   gentoo-silver  redglass

There they are. I can choose between any of these cursor themes by
referencing the name of the directory that holds the theme.

Some distributions have the inconsiderate habit of placing the cursor themes in the same directory as icon themes (different types of KDE or GNOME icons for your desktop). If your Linux distribution does this, not all of the theme names you find in the directory will be cursor themes. You'll know you've picked an icon theme by mistake if your desktop starts up with the default mouse cursors rather than a new cursor theme.

4.3.3. Set a Personal Default Theme

Each user can set his own
default cursor theme by creating
or modifying a file called
~/.icons/default/index.theme (recall that the
~ represents your home directory). This
index.theme file is the one that tells your
system which cursor theme to use. Create the directories you need
with the following command:

$ mkdir ~/.icons ~/.icons/default

Now use your favorite editor to create the
index.theme file in the
~/.icons/default directory. Place the following
two lines in the file:

[Icon Theme]
Inherits=whiteglass

This example assumes you have a cursor theme called Whiteglass
installed on your system (the earlier example showed that it exists
on my system, because the directory name
whiteglass appears in the
/usr/share/cursors/xorg-x11 directory that
contains all the globally available cursor themes). Obviously, if you
don't have the Whiteglass theme on your system, this
setting won't do you any good. The next time you
start your desktop, you'll see only the default
cursor theme, because Whiteglass doesn't exist. If
you don't have Whiteglass, substitute a theme name
that you do have installed.

Start up your favorite desktop window manager, and
voilà, you should see a new set of
mouse pointers.

If you want to change cursor themes, the best way to do it is to change the setting in the index.theme file, and then restart your window manager or desktop. If you don't restart the desktop, you could get unexpected results or no change in cursor theme at all.

4.3.4. Tips for Users of NVIDIA Display Cards

It is not uncommon
for people with NVIDIA display cards (such
as the GeForce series) to use the accelerated NVIDIA driver available
from the NVIDIA web site. If you're using the
accelerated driver, not the default driver that comes with X11, your
mouse cursors can tend to flicker.

Here's how to fix that problem. Find the
Device section for your NVIDIA card in your X11
configuration file. This file is called
XF86Config, XF86Config-4,
or xorg.conf, depending on the X server you are
using, and it is usually found in the /etc/X11
directory. Look for the Device section where you
define the video card driver. It should contain these lines, although
not necessarily exactly as they appear here:

Section "Device"
Driver   "NVIDIA"
Option   "HWCursor"    "On"

Turn off the HWCursor option so that it looks like
the following:

    Option   "HWCursor"    "off"

The next time you start up your desktop, the flicker problem should
be gone.

4.3.5. Get Custom Cursor Themes, Example 1

One popular source of custom cursor themes and other eye
candy is a site called KDE-Look (http://www.kde-look.org). The URL for cursor
themes is http://www.kde-look.org/index.php?xcontentmode=36.
Find a cursor theme you like and download it. Though this web site is
KDE-focused, the cursor themes work on any X server that meets the
earlier criteria.

Unfortunately, there's no standard way to package a
cursor theme. Different people package their cursor themes in
different ways, and not everyone includes a
README file to tell you how to unpack and
install their cursor themes. This makes it impossible to provide you
with one set of instructions on how to unpack and install a cursor
theme, and to expect those instructions to work for every theme you
download.

But there are some simple patterns to look for that make it easy to
adapt how you unpack and install cursor themes. For this example,
download the Red Dot cursor theme from the KDE-Look site. The URL for
this cursor theme is http://www.kde-look.org/content/show.php?content=4805
and the file (at the time of this printing) is called
4805-RedDot.tar.gz. Find or create a work
directory where you can unpack the file and change to that directory.
For example:

$ mkdir ~/temp
$ cd ~/temp

After you install the cursor theme, you can delete the contents of
this work directory. Decompress the file with the following command:

$ tar zxvf 4805-RedDot.tar.gz

This creates two directories,
RedDot and RedDotSource.
For those not familiar with it, the -z option
passed to GNU tar will uncompress gzipped files.

In general, once you unpack a cursor theme, the directories that
matter are the ones that contain a single subdirectory below them
called cursors. In this case, the
RedDot directory has a subdirectory called
cursors. That tells you which directory you want
to install. (For the curious, the RedDotSource
directory contains all the files the author of the theme used to
create the Red Dot theme.)

You can install the Red Dot cursor theme simply by copying the
RedDot directory and its contents to
~/.icons (the .icons
directory in your home directory):

$ cp -a RedDot ~/.icons

If you want the Red Dot cursor theme to be available to all users,
copy RedDot to one of the shared directories
instead. (Given the previous example of how this Linux distribution
is configured, the shared directories are
/usr/local/share/cursors/xorg-x11,
/usr/share/cursors/xorg-x11, and
/usr/share/pixmaps/xorg-x11. They might be
different for your system.) You need to log in as root to do this;
otherwise, you won't have the privileges necessary
to write to these directories.

Now edit the ~/.icons/default/index.theme file
to contain the following two lines:

[Icon Theme]
Inherits=RedDot

Start up your favorite window manager or desktop environment (or
restart the one you're using), and you should see
the Red Dot mouse cursors.

4.3.6. Get Custom Cursor Themes, Example 2

As I mentioned before, there's no
standard way to package a
cursor theme. So, here's another example of how to
install a cursor theme that should illustrate that the principles are
the same, even if the package is different.

In this case, download the Golden XCursors 3D theme, which (at the
time of this writing) is at http://www.kde-look.org/content/show.php?content=5507
and is located in a file called
5507-Golden-XCursors-3D-0.8.tar.bz2. Unpack the
file with the following command:

$ cd ~/temp
$ tar jxvf 5507-Golden-XCursors-3D-0.8.tar.bz2

This creates a subdirectory called
Golden-XCursors-3D-0.8. (If the version of
Golden Cursors has changed since the publishing of this book, the
filename will be different. Follow these instructions using the new
filename.) Change to this subdirectory with the following command,
and list that directory's contents:

$ cd Golden-XCursors-3D-0.8
$ ls
COPYING  Gold  README  default

In this case, the author created a README file,
but let's ignore it for a moment and use the same
reasoning used earlier to identify the relevant directory. Look in
the directory called Gold by issuing the
following command:

$ ls Gold
cursors

There's the cursors
subdirectory that we're looking for. So,
Gold is the directory we want. Copy the
Gold directory to the
~/.icons directory:

$ cp -a Gold ~/.icons

Again, if you want the Gold cursor theme to be available to all
users, copy Gold to one of the shared
directories instead. (Given the previous example of how this Linux
distribution is configured, the shared directories are
/usr/local/share/cursors/xorg-x11,
/usr/share/cursors/xorg-x11, and
/usr/share/pixmaps/xorg-x11. They might be
different for your system.) You need to log in as root to do this;
otherwise, you won't have the privileges necessary
to write to these directories.

Edit the ~/.icons/default/index.theme file to
contain these two lines:

[Icon Theme]
Inherits=Gold

Start up your favorite window manager or desktop environment (or
restart the one you're using), and you should see
the Gold mouse cursors.