I Can See Clearly Now, the Fonts Are Smooth

Isn't technology wonderful? There has never been an
easier time to run Linux. The progress we've seen
over the past few years is nothing short of amazing.
Today, from the comfort of your own keyboard, you
can browse for your favorite distribution, download it,
burn your own CD-Rs and install. In fact, I think it's
safe to say that the biggest hurdle holding users back
is fear of the unknown. But, Linux is an adventure and
that's half the fun.

I've been running Linux off and on for several years
now. When Red Hat 9.0 was released, I finally decided to
take the plunge and dedicate a machine to
running Linux full-time. The machine is pretty
decent: a gigabyte of RAM, plenty of disk space,
dual Athlon XP1600+ CPUs and two Nvidia graphics
cards used to support the three 21" monitors it has
attached (one graphic card has support for two monitor
connectors). Overall, installation was a breeze, and
Red Hat 9.0 recognized and configured all of the
devices just fine. About the only thing I had to do
was download and install the new graphics driver
from Nvidia and make some minor configuration
changes for the X server to recognize all three
monitors I had attached.

So, here I am working on my newly configured
machine. After playing around with all of the
goodies included in the distribution, I decide to
launch the browser and surf the Net for a while.
To my horror, the rendered text in Mozilla looked terrible.
The rods and cones in my eyes started going bonkers! As can be seen in
Figure 1, the characters were difficult to read and
full of jaggies. How could this be? Can't Linux do
better then this?
6854f1.gif Figure 1. Before Xft

Well, it can, with Xft.

Xft is a client-side API that works with the X
server to smooth out fonts and, if available,
leverage the X Render extension to accelerate text
drawing. If the X Render extension is not available,
it uses the base X protocol to draw the client-side
glyphs. This, however, can cause a severe
performance penalty as it involves fetching pixel
information, merging the glyphs with the pixels and
then sending them back. Thankfully, most modern
versions of Linux ship with X Render included so
this isn't be a problem.

Xft is only a single part of the infrastructure used
to anti-alias text on Linux. As mentioned above, X
Render is used to accelerate the process. Another
component, called Fontconfig, is used to select the
fonts and protocols used for rendering them. Yet
another component, called FreeType, is a font engine
used by Xft to rasterize the fonts. By
simply enabling anti-aliasing support in an
application, we are setting in motion a rather
complex chain of events and technologies used to
accomplish the task. The results can be seen in
Figure 2.
6854f2.gifFigure 2. After Xft

For applications to take advantage of Xft, they first need
to be compiled with the proper options and then
linked with the correct libraries. If you tend to
download and use pre-compiled Linux binaries,
chances are these are not Xft-enabled. To see if
your current version of Mozilla (or any application)
is Xft-enabled, simply check what libraries it
loads dynamically upon execution by using the ldd
command from a terminal window:

     cd /usr/lib/<your-mozilla-home-directory> 
     ldd mozilla-bin 

If you see libXft in the list, congratulations; your
browser already is enabled. Unfortunately, this
may not be the case for most users, who need either to find a pre-built version of Mozilla
with Xft enabled or to build it themselves.

I decided to build it myself. If you've never built
a large Linux application before, don't worry; it's
not that difficult. Over the years, I've found that
compiling software is a lot like cooking--the
results tend to be as good as the recipe used to
make it. As with cooking, you can change the recipe
to your liking, but you still need to know what
ingredients to change to get the desired results.
With that said, here is my personal recipe for
Xft-enabled Mozilla. All of these steps are done
from a single terminal window.

Step 1. Make sure the following five packages are
installed: XFree86-4.3, XFree86-100dpi-fonts-4.3, XFree86-75dpi-fonts-4.3,
XFree86-libs-4.3 and XFree86-xfs-4.3. The best way to find out if they are
installed is to issue an RPM query command:

     rpm -qa | grep XFree86

Step 2. You now are ready to download the source
code for the Mozilla browser. I suggest making a
local directory to hold everything:

     mkdir ~/mozilla-source 
     cd ~/mozilla-source 

Then download the latest stable Mozilla source:

     wget http://ftp25moz.newaol.com/pub/mozilla/
          releases/mozilla1.4a/src/
          mozilla-source-1.4a.tar.bz2 

Step 3. Unzip the tarball and create the .mozconfig
file if it is not present already:

     tar xvjf ./mozilla-source-1.4a.tar.bz2
     touch .mozconfig 

Step 4. The .mozconfig file tells the build scripts
how to configure the build, that is, what features to
enable and disable. Edit the .mozconfig and make
sure the following options are defined:

     ac_add_options --enable-crypto 
     ac_add_options --enable-optimize=Ó-O2 -march=i686Ó
     ac_add_options --enable-xft
     ac_add_options --disable-tests
     ac_add_options --disable-debug

Make sure you change march=i686 to something
appropriate for your system; if in doubt, use i386.
You also can choose to disable specific components--
Composer, Mail/News--by adding additional
options:

     ac_add_options --disable-composer 

Step 5. Next, a few environment variables need to be
defined before compiling:

     export MOZILLA_OFFICIAL=1
     export BUILD_OFFICIAL=1
     export MOZ_INTERNAL_LIBART_LGPL=1 

Step 6.Everything is ready now. First, run the
configure command to prepare things, ./configure. Upon completion,
begin the actual compilation process by typing make.
The make command takes a while to complete--almost an hour for me on a Dual Athlon XP1600+
system. You still can use your system, however; simple push
the terminal window into the background or minimize
it to the taskbar. As when baking a cake, check
in on it from time to time to make sure things are
moving along. Assuming your development environment is
set up properly, everything should go smoothly. If
something goes wrong, search the Web for help on
resolving the problem. A good place to find friendly
advice and assistance are the forums at
www.mozillazine.org.

Step 7. Assuming all went well, the final step is
to install the newly built executable. First, let's
get rid of all the excess junk generated during the
build process with:

     cd xpinstall/packager 
     make 

These commands create a tarball in
mozilla-source/mozilla/dist. Next, remove any
previous versions of Mozilla and install the new
Mozilla in /usr/local using:

     cd /usr/local 
     tar xzvf ~/mozilla-source/mozilla/dist/
         mozilla-i686-pc-linux-gnu.tar.gz 

You now can enjoy surfing the Net with
great looking fonts--your eyes will be sure to
thank you.

Jeff Sauer has been working with various
technologies for over 17 years. After working for
IBM, VeriSign and several successful startups, he now is
providing corporate training and consulting
services in the heart of Silicon Valley. He can be
reached through his Web site,
www.jouledata.com.