Linux get fonts list

Font configuration

Fontconfig is a library designed to provide a list of available fonts to applications, and also for configuration for how fonts get rendered. The FreeType library renders the fonts, based on this configuration. The freetype2 font rendering packages on Arch Linux include the bytecode interpreter (BCI) enabled for better font rendering especially with an LCD monitor. See #Fontconfig configuration and Font configuration/Examples.

Though Fontconfig is used often in modern Unix and Unix-like operating systems, some applications rely on the original method of font selection and display, the X Logical Font Description.

Contents

Font paths

For fonts to be known to applications, they must be cataloged for easy and quick access.

The font paths initially known to Fontconfig are: /usr/share/fonts/ ,

/.fonts/ , now deprecated). Fontconfig will scan these directories recursively. For ease of organization and installation, it is recommended to use these font paths when adding fonts.

To see a list of known Fontconfig fonts:

See fc-list(1) for more output formats.

Check for Xorg’s known font paths by reviewing its log:

Keep in mind that Xorg does not search recursively through the /usr/share/fonts/ directory like Fontconfig does. To add a path, the full path must be used:

For more details about Xorg configuration read, Xorg#Configuration. If you want font paths to be set on a per-user basis, you can add and remove font paths from the default by adding the following line(s) to

To see a list of known Xorg fonts use xlsfonts , from the xorg-xlsfonts package.

Fontconfig configuration

Fontconfig is documented in the fonts-conf(5) man page.

Configuration can be done per-user through $XDG_CONFIG_HOME/fontconfig/fonts.conf (usually $HOME/.config/fontconfig/fonts.conf ), and globally with /etc/fonts/local.conf . The settings in the per-user configuration have precedence over the global configuration. Both these files use the same syntax.

/.fontconfig/*.cache-* are deprecated and will not be read by default in the future versions of the package. New paths are $XDG_CONFIG_HOME/fontconfig/fonts.conf , $XDG_CONFIG_HOME/fontconfig/conf.d/NN-name.conf and $XDG_CACHE_HOME/fontconfig/*.cache-* respectively. If using the second location, make sure the naming is valid (where NN is a two digit number like 00 , 10 , or 99 ).

Fontconfig gathers all its configurations in a central file ( /etc/fonts/fonts.conf ). This file is replaced during fontconfig updates and should not be edited. Fontconfig-aware applications source this file to know available fonts and how they get rendered; simply restarting such applications is sufficient to load the new configuration. This file is a conglomeration of rules from the global configuration ( /etc/fonts/local.conf ), the configured presets in /etc/fonts/conf.d/ , and the user configuration file ( $XDG_CONFIG_HOME/fontconfig/fonts.conf ). fc-cache can be used to rebuild fontconfig’s configuration, although changes will only be visible in newly launched applications.

Fontconfig configuration files use XML format and need these headers:

The configuration examples in this article omit these tags.

Presets

There are presets installed in the directory /usr/share/fontconfig/conf.avail . They can be enabled by creating symbolic links to them, both per-user and globally, as described in /etc/fonts/conf.d/README . These presets will override matching settings in their respective configuration files.

For example, to enable sub-pixel RGB rendering globally:

To do the same but instead for a per-user configuration:

Anti-aliasing

Font rasterization converts vector font data to bitmap data so that it can be displayed. The result can appear jagged due to aliasing. The technique known as anti-aliasing can be used to increase the apparent resolution of font edges. Anti-aliasing is enabled by default. To disable it:

Hinting

Font hinting (also known as instructing) is the use of mathematical instructions to adjust the display of an outline font so that it lines up with a rasterized grid (i.e. the pixel grid of the display). Its intended effect is to make fonts appear more crisp so that they are more readable. Fonts will line up correctly without hinting when displays have around 300 DPI.

Byte-Code Interpreter (BCI)

Using BCI hinting, instructions in TrueType fonts are rendered according to FreeTypes’s interpreter. BCI hinting works well with fonts with good hinting instructions. Hinting is enabled by default. To disable it:

Autohinter

The autohinter attempts to do automatic hinting and disregards any existing hinting information. Originally it was the default because TrueType2 fonts were patent-protected but now that these patents have expired there is very little reason to use it. It does work better with fonts that have broken or no hinting information but it will be strongly sub-optimal for fonts with good hinting information. Generally common fonts are of the later kind so autohinter will not be useful. Autohinter is disabled by default. To enable it:

Hintstyle

Hintstyle is the amount of font reshaping done to line up to the grid. Hinting values are: hintnone , hintslight , hintmedium , and hintfull . hintslight will make the font more fuzzy to line up to the grid but will be better in retaining font shape (see [2]), while hintfull will be a crisp font that aligns well to the pixel grid but will lose a greater amount of font shape. hintslight implicitly uses the autohinter in a vertical-only mode in favor of font-native information for non-CFF (.otf) fonts.

hintslight is the default setting. To change it:

Pixel alignment

Most monitors manufactured today use the Red, Green, Blue (RGB) specification. Fontconfig will need to know your monitor type to be able to display your fonts correctly. Monitors are either: RGB (most common), BGR, V-RGB (vertical), or V-BGR. A monitor test can be found here.

Subpixel rendering

Subpixel rendering is a technique to improve sharpness of font rendering by effectively tripling the horizontal (or vertical) resolution through the use of subpixels. On Windows machines, this technique is called ClearType.

FreeType2 provides two different types of subpixel rendering, called Harmony and ClearType ( FT_CONFIG_OPTION_SUBPIXEL_RENDERING ) [3].

An LCD filter is recommended when ClearType subpixel rendering is enabled (Harmony subpixel rendering does not require setting an LCD filter). See the section below on how to enable an LCD filter and its benefits.

Starting from FreeType 2.10.3, Arch Linux enables ClearType subpixel rendering by default [4].

LCD filter

When using ClearType subpixel rendering, you should enable the LCD filter, which is designed to reduce colour fringing. This is described under LCD filtering in the FreeType 2 API reference. Different options are described under FT_LcdFilter, and are illustrated by this LCD filter test page.

The lcddefault filter will work for most users. Other filters are available that can be used in special situations: lcdlight ; a lighter filter ideal for fonts that look too bold or fuzzy, lcdlegacy , the original Cairo filter; and lcdnone to disable it entirely.

Advanced LCD filter specification

If the available built-in LCD filters are not satisfactory, it is possible to tweak the font rendering very specifically by building a custom freetype2 package and modifying the hardcoded filters. The Arch Build System can be used to build and install packages from source. This requires installation of the asp package.

Checkout the freetype2 PKGBUILD and download/extract the build files:

Enable ClearType subpixel rendering by editing the file src/freetype-VERSION/include/freetype/config/ftoption.h and uncommenting the FT_CONFIG_OPTION_SUBPIXEL_RENDERING macro.

Then, edit the file src/freetype-VERSION/src/base/ftlcdfil.c and look up the definition of the constant default_filter[5] :

This constant defines a low-pass filter applied to the rendered glyph. Modify it as needed. (reference: freetype list discussion) Save the file, build and install the custom package:

Reboot or restart X. The lcddefault filter should now render fonts differently.

Custom settings for certain fonts or font styles

The auto-hinter uses sophisticated methods for font rendering, but often makes bold fonts too wide. Fortunately, a solution can be turning off the autohinter for bold fonts while leaving it on for the rest:

Some fonts may not look good with BCI hinting. It can be disabled for just those fonts:

Replace or set default fonts

The most reliable way to set a default font is to add an XML fragment similar to the one below. Using the «binding» attribute will give you better results, for example, this will cause Ubuntu to be used in place of Georgia:

An alternate approach is to set the «preferred» font. Fonts matching the element are edited to prepend the list of

Whitelisting and blacklisting fonts

First obtain the Family name as listed in the font itself:

Then use that Family name in a stanza:

Typically when both elements are combined, is first used on a more general matching glob to reject a large group (such as a whole directory), then is used after it to whitelist individual fonts out of the larger blacklisted group.

Disable bitmap fonts

Bitmap fonts are sometimes used as fallbacks for missing fonts, which may cause text to be rendered pixelated or too large. Use the 70-no-bitmaps.conf preset to disable this behavior.

To disable embedded bitmap for all fonts:

To disable embedded bitmap fonts for a specific font:

Disable scaling of bitmap fonts

To disable scaling of bitmap fonts (which often makes them blurry), remove /etc/fonts/conf.d/10-scale-bitmap-fonts.conf . Note this can break the scaling of emoji fonts such as Segoe UI Emoji, making them huge.

Create bold and italic styles for incomplete fonts

FreeType has the ability to automatically create italic and bold styles for fonts that do not have them, but only if explicitly required by the application. Given programs rarely send these requests, this section covers manually forcing generation of missing styles.

Start by editing /usr/share/fonts/fonts.cache-1 as explained below. Store a copy of the modifications on another file, because a font update with fc-cache will overwrite /usr/share/fonts/fonts.cache-1 .

Assuming the Dupree font is installed:

Duplicate the line, change style=Regular to style=Bold or any other style. Also change slant=0 to slant=100 for italic, weight=80 to weight=200 for bold, or combine them for bold italic:

Now add necessary modifications to $XDG_CONFIG_HOME/fontconfig/fonts.conf :

Rule priority

Fontconfig processes files in /etc/fonts/conf.d in numerical order. Therefore the rules of 01-aaa.conf and 02-bbb.conf will have the same effect as a single 01-aaabbb.conf file containing first the rules of 01-aaa then the ones of 02-bbb .

Usually that means the files with the smaller prefix will have higher precedence. However, the fontconfig syntax is flexible and allows that a new rule takes precedence over an existing rule. Therefore it is recommended to #Query the current settings to test the result of the rule interactions.

Note that the user’s rules defined in $XDG_CONFIG_HOME/fontconfig/fonts.conf and in the directory $XDG_CONFIG_HOME/fontconfig/conf.d are loaded via the file /etc/fonts/conf.d/50-user.conf and typically take precedence over the rules defined in files starting with a higher number.

Query the current settings

To find out what settings are in effect, use fc-match —verbose . eg.

Look up the meaning of the numbers at fonts-conf(5) Eg. ‘hintstyle: 3’ means ‘hintfull’

Applications without fontconfig support

Some applications like URxvt will ignore fontconfig settings. You can work around this by using

/.Xresources , but it is not as flexible as fontconfig. Example (see #Fontconfig configuration for explanations of the options):

Make sure the settings are loaded properly when X starts with xrdb -q (see X resources for more information).

Troubleshooting

Force emoji font

Some software may lacks proper Emoji font fallback support.

To force emoji presentation create emoji font fallback preset for your application, to enable see #Presets. Replace application with your application’s executable’s basename and Noto Color Emoji with your preferred emoji font:

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Distorted fonts

This section is being considered for removal.

If fonts are still unexpectedly large or small, poorly proportioned or simply rendering poorly, fontconfig may be using the incorrect DPI.

Fontconfig should be able to detect DPI parameters as discovered by the Xorg server. You can check the automatically discovered DPI with xdpyinfo (provided by the xorg-xdpyinfo package):

If the DPI is detected incorrectly (usually due to an incorrect monitor EDID), you can specify it manually in the Xorg configuration, see Xorg#Display size and DPI. This is the recommended solution, but it may not work with buggy drivers.

Fontconfig will default to the Xft.dpi variable if it is set. Xft.dpi is usually set by desktop environments (usually to Xorg’s DPI setting) or manually in

/.Xresources . Use xrdb to query for the value:

Those still having problems can fall back to manually setting the DPI used by fontconfig:

Calibri, Cambria, Monaco, etc. not rendering properly

Some scalable fonts have embedded bitmap versions which are rendered instead, mainly at smaller sizes. Using Metric-compatible fonts as replacements can improve the rendering in these cases.

You can also force using scalable fonts at all sizes by disabling embedded bitmap, sacrificing some rendering quality.

Applications overriding hinting

Some applications or desktop environments may override default fontconfig hinting and anti-aliasing settings. This may happen with GNOME 3, for example while you are using Qt applications like vlc or smplayer . Use the specific configuration program for the application in such cases. For GNOME, try gnome-tweaks .

Applications not picking up hinting from GNOME settings

For instance, under GNOME it sometimes happens that Firefox applies full hinting even when it’s set to «none» in GNOME’s settings, which results in sharp and widened fonts. In this case you would have to add hinting settings to your fonts.conf file:

In this example, hinting is set to «grayscale».

Incorrect hinting in GTK applications

In some desktop environments, especially outside GNOME and Plasma, some GTK applications could not read font configuration properly. In order to solve this issue, install xsettingsd or xsettingsd-git AUR and execute it at every system startup. See also Xsettingsd and xsettingsd wiki for more information. It can be configured with the following common configuration:

If that is not working in some other applications, you could install xorg-xrdb and provide the following configuration:

Then you can execute the script xrdb -merge

/.Xresources at every system startup to apply the options. See also X resources and #Applications without fontconfig support.

Helvetica font problem in generated PDFs

If the following command

then the bitmap font provided by xorg-fonts-75dpi is likely to be embedded into PDFs generated by «Print to File» or «Export» in various applications. The bitmap font was probably installed as a consequence of installing the whole xorg group (which is usually NOT recommended). To solve the pixelized font problem, you can uninstall the package. Install gsfonts (Type 1) or tex-gyre-fonts (OpenType) for corresponding free subsitute of Helvetica (and other PostScript/PDF base fonts).

You may also experience similar problem when you open a PDF which requires Helvetica but does not have it embedded for viewing.

FreeType breaking bitmap fonts

Some users are reporting problems (FS#52502) with bitmap fonts having changed names after upgrading freetype2 to version 2.7.1, creating havok in terminal emulators and several other programs such as dwm or dmenu by falling back to another (different) font. This was caused by the changes to the PCF font family format, which is described in their release notes [5]. Users transitioning from the old format might want to create a font alias to remedy the problems, like the solution which is described in [6], given here too:

Assume we want to create an alias for terminus-font , which was renamed from Terminus to xos4 Terminus in the previously described freetype2 update:

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• Create a configuration file in /etc/fonts/conf.avail/ for the font alias:

• Create a symbolic link towards it in the /etc/fonts/conf.d directory. In our example we would link as follows: ln -s /etc/fonts/conf.avail/33-TerminusPCFFont.conf /etc/fonts/conf.d to make the change permanent.

Everything should now work as it did before the update, the font alias should not be in effect, but make sure to either reload .Xresources or restart the display server first so the affected programs can use the alias.

Underscores not rendered with Dejavu Monospace

Since Pango 1.44, the underscore characters disappear with certain font sizes when using the DejaVu Sans Mono font. A workaround is to use Liberation Mono as the monospace font, see #Replace or set default fonts.

Debugging FreeType fonts

freetype2-demos provides tools for debugging FreeType font configuration. ftview is a GUI in which you can tweak font rendering settings with a live preview. For example:

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