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4. XFree86 4.x

XFree86 4.0 introduced native support for TrueType fonts, along with other new features. The enhanced font support is based on xfsft from Juliusz Chroboczek, which in turn is based on the FreeType font library originally from Mark Leisher, so the configuration is similar to xfsft and Red Hat's patched xfs which use the same rendering engine. As of 4.0.2, XFree86 begins to support anti-aliasing which is a technique for smoothing font outlines (see section below).

The FontPath is still in XF86Config, as always. For Red Hat 6/7 using a stock XFree86 4.x (i.e. NOT the Red Hat 7.x supplied version), this will mean moving the Red Hat xfs FontPath from /etc/X11/fs/config back to XF86Config. A separate font server is no longer needed just for TrueType support. You may disable it, unless it is needed to serve fonts to other clients in a network environment. Or you may want to still use it since there may be a very small performance gain in some situations (at the cost of more memory utilized). See the section below for Red Hat 7.x specific configuration issues.

 Section "Files"
  FontPath "/usr/X11R6/lib/X11/fonts/misc:unscaled"
  FontPath "/usr/X11R6/lib/X11/fonts/100dpi:unscaled"
  FontPath "/usr/X11R6/lib/X11/fonts/75dpi:unscaled"
  FontPath "/usr/X11R6/lib/X11/fonts/misc"
  FontPath "/usr/X11R6/lib/X11/fonts/Type1"
  FontPath "/usr/X11R6/lib/X11/fonts/Speedo"
  FontPath "/usr/share/fonts/default/Type1"
  FontPath "/usr/local/share/fonts/ttfonts"
  FontPath "/usr/X11R6/lib/X11/fonts/100dpi"
  FontPath "/usr/X11R6/lib/X11/fonts/75dpi"
 EndSection
    

In order to use TrueType, you must also specify which font module the X server should be using in the "Module" section:

 Section "Module"
  Load  "freetype"
  Load  "speedo"
  Load  "type1"
  <load other modules....>
 EndSection
    

Note that there can be only one 'Module' section, so include any other modules here as well. Again, this is the kind of configuration that your distro should be doing during installation, and may not be necessary, unless you are upgrading, or want to make manual changes yourself.

You also must have a fonts.scale and fonts.dir file for each TrueType font directory, just like for xfsft and Red Hat's xfs (see Appendix). ttmkfdir, http://www.joerg-pommnitz.de/TrueType/ttmkfdir.tar.gz, will come in handy for fonts.scale if it is not already installed. See the Configuration section above for more details and examples.

xtt is another available TrueType module that is best known for supporting ideographic (Oriental) type fonts. You can use either, but only one at a time.

Most X server command line options are still the same as previous versions of X:

$ startx -- -dpi 100

4.1. Xft and Core Fonts

As mentioned, the new font handling improvements are the result of the development work behind Xft. Xft is an on-going effort to improve and modernize X's font handling. The end result will be radically different from the traditional X font handling (known as "core X fonts").

What we have now is essentially two different systems: one that has been around since the dawn of time (or even before :), and one that is radically new and still evolving! I emphasize this, since the "still evolving" part is likely to cause some confusion until the dust settles.

The initial release of Xft v1.0 with XFree86 4.0.2 is controlled by its configuration file, XftConfig. This changes with later versions, where the font configuration is handled by the fontconfig library, with its main configuration typically located /etc/fonts/fonts.conf. Of course, additional development has brought other improvements as well. For more on the Xft and Fontconfig, see the Fontconfig home page, http://fontconfig.org/.

What we, as end users, will notice and appreciate most, is the anti-aliasing support and other rendering enhancements we get from Xft. Though this is not the only benefit.

4.2. Anti-aliasing

Anti-aliasing is a technique for producing even smoother, crisper looking fonts by subtly softening the sharp, jagged edges. This has long been a feature of Apple and Microsoft font rendering, and is now making it's way into X via the X Rendering Extension specification. The new extensions provide other benefits as well. Distributions that support anti-aliasing with their stable/official versions are now being released.

That is the good news. The bad news is that not all drivers support anti-aliasing yet. This is a moving target, so you will have to dig around to find whether your chipset is supported or not. The recently released 4.2 should have near universal support. More not-so-good news is that not all applications are actually taking advantage of this yet. We will have to wait for the various toolkits (TK, Xaw, etc) to catch up. KDE is an exception, and has had strong AA support via the QT toolkit. The recently released GNOME-2, has AA support now too.

Anti-aliasing is not a cure-all, but is another piece of the font puzzle. Some point sizes may look better if not anti-aliased, and some systems just may not handle the various rendering enhancements as well as others.

If you are reading this long after the publication date (October 2002), hopefully most of these shortcomings will have been overcome. All hardware will eventually be supported, mainstream distros will have shipped releases that include the new extensions, and they will be enabled by default. Many apps will look better since they will be "AA" aware, and we won't have to jump through any configuration hoops just to make it work. In the meantime, read on ...

4.2.1. Requirements

Minimum requirements for Anti-Aliasing:

  • XFree86 4.0.2 or later.

  • You graphic card's driver has to support anti-aliasing. If 4.0.2 (or greater) is already installed, you can get this information direct from the driver with xdpyinfo. Run this and look for "Number of Extensions:". If this lists "RENDER" among them, then you should be good to go. If not, well, it isn't going to work, and you will have to wait for an updated driver.

  • The Freetype2 library available from http://www.freetype.org, and also now bundled with XFree86. XFree needs to be linked against this, so install and build first if building from scratch. Your distro should have Freetype packages as well. Just make sure it is freetype-2.

  • TrueType fonts are best for display purposes. Type 1 is also good, but may not render quite as well. See above sections.

  • For KDE users, KDE supports anti-aliasing as of 2.x. This will require QT-2.3.0 or later, and built with Xft support. A nice font HOWTO from Troll Tech for KDE and QT can be found: http://trolls.troll.no/lars/fonts/qt-fonts-HOWTO.html.

    GNOME 1.x does not support anti-aliasing. GNOME 2.0 has recently been released and does have native support for anti-aliasing.

  • Applications that "know" about anti-aliasing. Not necessarily at the individual application level, but the libraries and toolkits (GTK, TK, etc.) that the application are built against, must be able to use the new features. At this time, not all do. KDE/QT is first out of the box and has good support. Also, xterm (yes, xterm!) supports the new extensions. An interesting example scavenged off usenet:

         
        From torvalds@penguin.transmeta.com Sun Apr 28 02:09:28 2002
        From: torvalds@penguin.transmeta.com (Linus Torvalds)
        Newsgroups: comp.os.linux.x
        Subject: Re: X font recommendation
        Organization: Transmeta Corporation
        Lines: 24
        Message-ID: <aa4ijq$259$1@penguin.transmeta.com>
        Cache-Post-Path: palladium.transmeta.com!unknown@penguin.transmeta.com
        Date: Tue, 23 Apr 2002 21:10:18 +0000 (UTC)
        X-Trace: news.sjc.globix.net 1019596253 63.209.4.196 (Tue, 23 Apr 2002 14:10:53 PDT)
        NNTP-Posting-Date: Tue, 23 Apr 2002 14:10:53 PDT
    
        In article <aa492r$7hc5u$2@ID-99293.news.dfncis.de>,
        William Park  <opengeometry@NOSPAM.yahoo.ca> wrote:
        >Peter Karlsson <root@localhost.localdomain> wrote:
        >> What's wrong with "fixed"? :-)
        >> 
        >> xterm -sb -sl 10000 -fg yellow -bg black -geometry 120x40 -fn fixed -bc
        >
        >This will load the default 6x13 fonts, aka.
        >    -misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso8859-1
        >A bit too small, though it has correct proportions.  If there is bigger
        >size (8x16, 10x20, 12x24) of that fonts, then that would be ideal.
    
        If you like anti-aliased fonts, the command line I prefer happens to be
    
             xterm -geometry 100x40 -fa andale:size=11:charwidth=6
    
        I think that font is from the MS free fontpack.
    
        In order for it to work for you, you need to have the anti-aliasing
        truetype fonts working well, and probably a good monitor (and some
        people _hate_ that rounded look from anti-aliasing, and find it fuzzy
        even then).
    
                  Linus
         
       

    You might have to experiment with the size and charwidth values to get reasonable results.

  • The new rendering extensions configuration file, XftConfig, must be configured for the fonts you want to use. Note that as of Xft2, this changes to /etc/fonts/fonts.conf.

  • The new extensions supplant much of what we have been doing with font servers like xfs. fonts.alias and similar configuration files, for instance, are not used for fonts that are being controlled by the new extensions. Essentially, this gives us two separate font handling engines: the traditional, "core" font engine, and the new, Xft engine. The core engine is still used in some situations.

4.2.2. Installation

Keith Packard has a very brief summary of the steps required for building, installing and configuring from source at http://www.xfree86.org/~keithp/render/aafont.txt. No need to reprint it here.

Newer distro releases are likely to have the foundation support for anti-aliasing available now. Red Hat, for instance, has it available as of Red Hat 7.1.

To verify the necessary components, first make sure the "freetype" module (and any others) are loaded. Check the X server output:


 (II) LoadModule: "freetype"
 (II) Loading /usr/X11R6/lib/modules/fonts/libfreetype.a
 (II) Module freetype: vendor="The XFree86 Project"
        compiled for 4.0.3, module version = 1.1.9
        Module class: XFree86 Font Renderer
        ABI class: XFree86 Font Renderer, version 0.2
 (II) Loading font FreeType

Then verify if the "RENDER" extension is available, either check with xdpyinfo, or check the X server log, typically /var/log/XFree86.0.log:

 
 (II) Initializing built-in extension MIT-SHM
 (II) Initializing built-in extension XInputExtension
 (II) Initializing built-in extension XTEST
 (II) Initializing built-in extension XKEYBOARD
 (II) Initializing built-in extension LBX
 (II) Initializing built-in extension XC-APPGROUP
 (II) Initializing built-in extension SECURITY
 (II) Initializing built-in extension XINERAMA
 (II) Initializing built-in extension XFree86-Bigfont
 (II) Initializing built-in extension RENDER

If "RENDER" is there, anti-aliasing and the other advanced rendering extensions should be available. If not, the system should gracefully fall back to the core X fonts engine.

4.2.3. Xft Configuration (XftConfig)

By Danny Tholen

Xft is an interface to the freetype rasterizer written by Keith Packard, member of the XFree86 Project, Inc. It allows applications to use fonts from the new X render extension using a unified font naming scheme. In /etc/X11/XftConfig (or /usr/X11R6/lib/X11/XftConfig) you will find a configuration file which can be adapted to suit your personal taste. In this section I will explain the syntax and demonstrate some things you can do with this file.

The following information is based on 4.0.3. 4.1 is just released, and there may be a few new wrinkles not touched on here. Future versions are sure to bring even more radical changes.

Note that Xft2 makes radical changes to Xft configuration. XftConfig is obsoleted and replaced by the new fontconfig libraries. Red Hat 8.x users should read the Red Hat 8.0 Differences section first. Many of the principles described still apply, but the configuration is radically different. FYI.

4.2.3.1. XftConfig Structure

The basic structure revolves around a 'pattern'. A pattern is a set of name/value-list pairs, each value-list contains one or more typed values. A certain application requests a font, for example:

 family: "Arial"
 size: 12
 encoding: "iso8859-1"
    

A size 12 arial font in latin-1 encoding. The Xft extension will now try to patch this pattern to all of the fonts available in the system. And selecting the one with the best score. Before the matching is done Xft looks in XftConfig. The requested pattern can here be extended before use. An example is:

 match any family == "Arial" edit antialias = true;
   

This will enable anti-aliasing for all fonts of the family Arial.

Also, the X server is queried to list all of its fonts; the XLFD contains just enough information to match fonts roughly.

Here's a list of attributes used in matching fonts (in priority order, this may not be up to date anymore!):

 foundry        font foundry (string, like "monotype")
 encoding       font encoding (string, like "iso8859-1")
 spacing        font spacing (integers or proportional (0), mono (100), 
                charcell (110))
 bold           is the font bold? (boolean)
 italic         is the font italic? (boolean)
 antialias      is the font anti-aliased? (boolean)
 family         font family (string)
 size           font size (double)
 style          font style (string, like "Bold Italic")
 slant          font slant (roman, italic, oblique)
 weight         font weight ( integers or light, medium (100), demi-bold, 
                bold, black)
 rasterizer     not yet used (probably "TrueType", "Type1", ...)
 outline        are outlines available? (boolean)
   

4.2.3.2. XftConfig Syntax

4.2.3.3. XftConfig Examples

And now I´ll try to list a few useful configurations and explain them. Note that it is configured for my system, and I may use different fonts than you, so try to adapt the examples to your own needs.

  1. How do I make fonts available to Xft?

    List your Type 1 and TrueType font directories with "dir". On my system (Mandrake 7.2) this becomes:

     dir "/usr/X11R6/lib/X11/fonts/Type1"
     dir "/usr/X11R6/lib/X11/fonts/drakfont"
        

  2. How do I use a user specific XftConfig file?

    Put an .xftconfig file in your user directory and add:

     includeif   "~/.xftconfig"
        

    to your standard XftConfig. This will enable a user specific configuration file, but it will not complain if there is no such file.

  3. How do I make aliases for my fonts?

    I noted that my KDE console asks for "mono" fonts when it is looking for a fixed font. "console" is used when I select "linux" in the font menu of the KDE konsole. Therefore, I used two aliases for fonts which are also named "fixed":

     match any family == "fixed"     edit family =+ "mono";
     match any family == "console"   edit family =+ "mono";
        

  4. Anti-aliasing my fonts are blurry and makes me dizzy!

    Although there is a big fuzz around AA in X, good fonts actually look better if they are not anti-aliased. The anti-aliasing blurs the fonts by adding gray pixels to the edges, and this may strain your eyes if you looking at them for a long time. (Your eyes will try to get the fonts sharper, which of course is not working because they are blurred;) However, for very small fonts, anti-aliasing may increase the readability of the fonts, because with sharp edges, there are too little pixels available for your mind to figure out what it means. And for bigger fonts, the edges become very jagged when not anti-aliased, so here you also might want to have aliased fonts. Of course you can also turn off the anti-aliasing for specific fonts. In other operating systems, most truetype fonts are not anti-aliased between 8 and 12 pixels, while only large Type1 fonts are anti-aliased.

    Use the following in your XftConfig to anti-alias only fonts of specific sizes:

     match 
           any size > 8 
           any size < 15 
     edit 
           antialias = false;
        

  5. My fixed fonts do not appear or look _very_ wrong in the KDE konsole or similar programs!

    I noted that somehow a lot of fixed font do not tell Xft that they are fixed, and thus, mono spaced. Therefore only a part of the font is displayed. We can manually set the spacing for these fonts (this assumes you have fixed aliased with mono as in question 3 above):

     match 
           any family == "mono" 
     edit 
           spacing = mono;
        

  6. My Symbol, Webdings, etc. fonts do not show up!

    For some reason some (symbol) fonts are not correctly recognized, and Xft will show your default font, or a font which has the closest match (which is generally not what you mean at all). For Adobe Symbol and MS-webdings I did the following to get them working:

     match 
           any family == "webdings" 
     edit 
           antialias = false;
           encoding += "glyphs-fontspecific";


     match 
           any family == "symbol" 
     edit 
           antialias = false;
           encoding += "glyphs-fontspecific";
        

    A useful way of figuring out these things is to activate debugging with:

     export XFT_DEBUG=1024
        

    This will generate a lot of output, especially if you have many fonts, because it lists the properties and scores of every font available. You can also use other values. For a nice summary of what happens (requested font, XftConfig substitutions, X server additions and the finally matched font), you can use XFT_DEBUG=2.

  7. Why do my KDE programs start now soooo slooow?

    The Xft mechanism in XFree prior to 4.1 had to parse the XftConfig file each time a program was started. And the info of all these fonts had to be re-read. As of X 4.1.0, a cache is used and starting applications using Xft is much faster. Especially if you have many fonts this can be very useful. So, upgrading XFree86, and related packages, is a good idea.

  8. I have a LCD screen on my laptop, can I use sub-pixel hinting instead of normal anti-aliasing?

    Yes you can. Sub-pixel hinting uses colors instead of gray pixels to do the AA. I do not have a LCD screen so I do not have any idea of how it looks but you can play with the "rgba" setting. Try:

     match edit rgba=bgr;
        

    or use rgb if you have a different type of monitor. For vertical AA you can try vbgr and vbgr.

  9. My fonts still look bad!

    Good quality fonts are needed to start with. If you do not have some good TrueType fonts, it is worth it to go and look for them on the Internet. Other reasons why your fonts still look bad can be because of your build of freetype2. Snapshots versions before 2.0.2 were compiled with an option that had some patent issues. Therefore, the standard 2.0.2 and 2.0.3 compiles without this option. To fix this, download the freetype2 source rpm and change in include/freetype/config/ftoption.h line 314:

      #undef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
        

    to:

      #define TT_CONFIG_OPTION_BYTECODE_INTERPRETER
        

    and rebuild with this modified source. See the freetype2 README file for details. Adobe Courier looks terrible on my system, so I made an alias so that Lucida console is displayed instead. If anyone can get it to display nicely I would appreciate knowing about it.

This is my XftConfig:

#
# XftConfig
#
# By: Danny Tholen
#
# Use with Type1 and TrueType fonts
#

dir "/usr/X11R6/lib/X11/fonts/Type1"
dir "/usr/X11R6/lib/X11/fonts/drakfont"
dir "/usr/share/fonts/default/Type1" 

#
# alias 'fixed' and 'console' for 'mono'
# (some programs ask for 'mono' if they mean 'fixed';)
#
match any family == "fixed"        edit family =+ "mono";
match any family == "console"      edit family =+ "mono";


#
#Check users config file
#
includeif     "~/.xftconfig"


#
# Use TrueType fonts for defaults
# Danny: disabled
#match any family == "serif"       edit family += "Times New Roman";
#match any family == "sans"        edit family += "Verdana";


#
# Use lucida console as default fixed type font
# and set the spacing of "mono" to 100, this
# fixes broken fonts which are fixed, but do not
# set mono-spacing.
match
      any family == "mono" 
edit
      family += "lucida console";
      spacing = 100;


#
# Alias between XLFD families and font file family name, prefer local fonts
#
match any family == "Charter"           edit family += "Bitstream Charter";
match any family == "Bitstream Charter" edit family =+ "Charter";

match any family == "Lucidux Serif"     edit family += "LuciduxSerif";
match any family == "LuciduxSerif"      edit family =+ "Lucidux Serif";

match any family == "Lucidux Sans"      edit family += "LuciduxSans";
match any family == "LuciduxSans"       edit family =+ "Lucidux Sans";

match any family == "Lucidux Mono"      edit family += "LuciduxMono";
match any family == "LuciduxMono"       edit family =+ "Lucidux Mono";


#
# TrueType font aliases
#
match any family == "Comic Sans"        edit family += "Comic Sans MS";
match any family == "Comic Sans MS"     edit family =+ "Comic Sans";
match any family == "Trebuchet"         edit family += "Trebuchet MS";
match any family == "Trebuchet MS"      edit family =+ "Trebuchet";
match any family == "Monotype"          edit family =+ "Monotype.com";
match any family == "Andale Mono"       edit family += "Monotype.com";
match any family == "Monotype.com"      edit family =+ "Andale Mono";


# Danny:
# set the AA for different fonts
#
# most TT fonts do not need to be aliased between
# 8 and 15 points, although this might be a matter of taste.
match 
      any size > 8
      any size < 15
edit
      antialias = false;


# Danny: Courier looks terrible, and I
# cannot get most characters to fit nicely
# in their space. So I use courier 10 pitch
match 
      any family == "courier" 
edit
      family += "courier 10 pitch";


# these are symbols, and for some reason this needs to be added!:

match 
      any family == "webdings" 
edit
      antialias = false;
      encoding += "glyphs-fontspecific";

match 
      any family == "symbol" 
edit
      antialias = false;
      encoding += "glyphs-fontspecific";

match 
      any family == "Standard Symbols L" 
edit
      antialias = false;
      encoding += "glyphs-fontspecific";

match 
      any family == "dingbats" 
edit
      antialias = false;
      encoding += "glyphs-fontspecific";

match 
      any family == "Cursor" 
edit
      antialias = false;
      encoding += "glyphs-fontspecific";


# maybe arial looks better like this?:
match 
      any family == "Arial" 
      any size > 7
      any size < 15
edit
      antialias = false;


# end
    

4.2.4. GTK and GNOME

As mentioned above, KDE and QT do have solid anti-aliasing support with recent releases. GNOME-2 has just recently been released as of this writing (as of Aug 2002), and does have support for anti-aliasing, though is not in widespread use (yet).

There is also the gdkxft project available at http://sourceforge.net/projects/gdkxft/. This will add anti-aliasing support to GTK+ 1.2 applications (only!). This is a stand-alone library and not a patch. It will only effect GTK+ 1.x widgets (many of them but not all). There are some limitations, but mostly it works as advertized. Read the included README closely, and follow the instructions. An initial installation provides a good starting point. I added some font families to /etc/gdkxft.conf and I used some of Danny's suggestions above, and it seems to work mostly. It's a bit of a kludge, but quite a nice kludge ;-) Note, sadly this project seems to be no longer maintained.

There is also a couple of ways to get this working with Mozilla! On the same page above is a replacement library that can be substituted for the Mozilla library of the same name. Just a drop in replacement. But, this did not work here (on Red Hat 7.2), it segfaulted. But building Mozilla from source with the patch listed, did indeed work nicely! This step requires gdkxft to be working as well. So it's a two step process to get Mozilla working, but worth the effort if you want the best looking pages IMHO. There are also development versions of Mozilla available from ftp://ftp.mozilla.org/pub/mozilla/nightly/experimental/xft/ that have Xft/TrueType support (see the section on Mozilla below). Native Mozilla Xft support is probably working its way into mainstream releases. [Note: This should happen with Mozilla 1.2.]

4.3. Red Hat 7.x and 8.x Differences




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