4. XFree86 4.x

4.1.3.1. XftConfig Structure

The basic structure revolves around a 'pattern'. A pattern is a set of name/valuelist pairs, each valuelist 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 antialiased? (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)
   

4.1.3.2. XftConfig Syntax

• dir

  Adds a directory to the list of places Xft will look for fonts. There is no particular order implied by the list; Xft treats all fonts about the same.

• include and includeif

  Cause Xft to load more configuration parameters from the indicated file. "includeif" doesn't elicit a complaint if the file doesn't exist. If the file name begins with a "~" character, it refers to a path relative to the home directory of the user. This is useful for user-specific configurations.

• match edit

  If a pattern from an application matches the pattern after "match", it is edited with the instructions in edit. The pattern match is done as follows:

    match qual FIELD-NAME COMPARE CONSTANT
       

  where qual is either any (matches one specific font) or all (matches all fonts). An example:

   match all foundry==�monotype�
     

  which will match (and edit) all fonts belonging to the foundry "monotype".

   match any family==�arial�
     

  will match (and edit) one specific font with the family name "arial".

  FIELD-NAME is any one of the properties found in the above section Structure, or additionally:

   pixelsize        font size in pixels (integer)
   charspace        character space (integer)
   minspace         minimal spacing (integer)
   rgba             color hinting (string �rgb� or �bgr� and
                    vertical hinting �vrgb� �vbgr�)
   xlfd             x server font (string, type xlsfonts to
                    see a list of your xlfd strings)
   file             the font file (string)
   core             use X core fonts? (boolean)
   render           use render fonts? (boolean)
   index            I have no idea what this does:)
   scalable         is the font scalable (boolean)
   scale            scale the font (integer)
   charwidth        character width (integer)
   charheight       character height (integer)
   matrix           no idea (not really at least)
     

  COMPARE can be <, >, or ==.

  CONSTANT is the value of the field-name in the appropriate type (see above section Structure).

  You can use multiple matches before you use the "edit" statement:

   edit FIELD-NAME ASSIGN EXPR SEMI
       

  Where ASSIGN can be one of =, += or =+. With =, the matching value in the pattern will be replaced by the given expression. += or =+ will prepend/append a new value to the list of values for the indicated field.

  EXPR sets the FIELD-NAME to a value.

  SEMI is a semicolon (;). You can use multiple instructions, separated by a semicolon. See below for examples if this is confusing.

4.1.3.3. 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 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 to 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, can I use subpixel hinting instead of normal anti-aliasing?

   Yes you can. Subpixel 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!

   If you do not have some good truetype fonts, it is worth 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 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