7.4 Linux Fonts

The most common Linux fonts containing significant math coverage are the DejaVu fonts. The DejaVu font family consists of three typefaces: DejaVu Sans, DejaVu Serif, and DejaVu Mono. Both the DejaVu Sans and DejaVu Serif fonts are encountered on 97 percent of Linux desktops. The accompanying tables (Table 9 and Table 10 respectively) summarize their coverage of mathematical notation.

It is also worth noting that the DejaVu fonts (like the STIX fonts) have bold, italic, and bold italic variants which also provide significant math coverage. For the sake of brevity, we will spare you the details. Suffice it to say, the math coverage in these variants is less extensive than their upright counterparts, and roughly equivalent to their STIX counterparts.

The GNU FreeFont family consists of three typefaces: FreeSans, FreeSerif, and FreeMono. The fonts contain extensive math coverage and are found on approximately 85 percent of Linux desktop installations. Table 11 summarizes the mathematical coverage of one of the fonts, FreeSerif. The other faces have similar coverage. Most of the glyphs used by LaTeX are available in the GNU FreeFonts.

The GNU FreeFonts, like the STIX fonts, have bold, italic, and bold italic variants which also provide significant math coverage. As is typically the case, the math character set of these variants is less extensive than their upright counterparts.

In 2007, Red Hat commissioned the Ascender Corp font foundry to create a set of fonts, dubbed the Liberation fonts – Liberation Sans, Liberation Serif, and Liberation Mono – that are metric equivalents of the common Microsoft fonts: Times New Roman, Arial, and Courier New. Metric equivalence implies that the Liberation fonts have identical horizontal spacing to the Microsoft fonts. When Liberation fonts are substituted for the Microsoft fonts, a line of text is laid out in an identical manner. Red Hat’s motivation for this “act of generosity” was Microsoft’s refusal to license its popular fonts on the Linux platform, which caused inconsistent cross platform display of office documents.

The Liberation fonts have recently (July 2012) received a facelift by the Fedora Project. The revised fonts, dubbed Liberation 2.0, are based on Google’s Chrome OS Croscore fonts (which were, in turn, based on the original Liberation fonts). The main impetus for this change was to resolve issues with the licensing terms of the original Liberation fonts, which impeded “community based” font enhancements.

In any event, both flavors of the Liberation fonts provide poor mathematical symbol coverage. Table 12 summarizes the coverage of the Liberation 2.0 Serif font, which is known as Tinos in the Chrome OS/Crosscore world. Mathematical coverage is equally spotty in the Liberation Sans (Armino) and Liberation Mono (Cousine) typefaces.

For the record, the Liberation fonts (first version) are installed on 89 percent of Linux desktops.

In 2010, the Dalton Maag type foundry delivered new sans serif typefaces to Canonical for use as the signature font for its Ubuntu Linux distribution. These fonts – called simply the Ubuntu Font Family - have limited math symbol coverage. As with most Linux fonts, Ubuntu has significant coverage of Greek characters. In math coverage, these fonts are similar to the Liberation fonts or the Postscript fonts. Table 13 summarizes the coverage of the Ubuntu Regular font.

The Ubuntu fonts are installed on 63 percent of Linux desktops.

When Adobe introduced Postscript in 1984, they defined 35 core fonts (in 10 typefaces) that must be present in all Postscript interpreters. The Ghostscript fonts are commercial quality implementations of the Postscript core fonts that were donated to the Ghostscript project in 1996 by the URW++ Design & Development type foundry of Hamburg. The Tex Gyre fonts are a recent incarnation of the “Ghostscript” fonts that are packaged and extended by the Polish type foundry GUST e-font. They are discussed in Section 7.5.3.

The relationship between the original Postscript core fonts, their Ghostscript counterparts, and their more recent Tex Gyre implementation is described in Table 14.

In general, these fonts alone do not provide adequate coverage for mathematical publication. They were not designed for publishing advanced mathematics and must be augmented by one of the more comprehensive math fonts. However, it should be noted that the Ghostscript “Standard Symbol L” (Table 15) does provide basic math coverage. Furthermore, the recent “Tex Gyre Pagella Math” extension (Table 18) provides comprehensive math support for Tex Gyre’s Paagella (Palatino) font.

The Ghostscript fonts are among the most universal of the Linux fonts. In a recent survey – URW Chancery L, Century Schoolbook L, URW Gothic L, Nimbus Sans L, URW Bookman L, URW Palladio L, Nimbus Mono L, Nimbus Roman No9 L – i.e. the Ghostscript fonts, were installed on more than 98% of the monitored Linux desktops.

The fonts discussed in this section are packaged by virtually all Linux distributions, even if they are not loaded onto the system during a distribution’s default installation procedure. Hence, most Linux users can, and probably should, install these fonts through their distribution’s package management system.

We referenced the upstream source of each font during our discussion. The upstream font publishers package their fonts in an operating system neutral manner. If the proper procedures are followed, fonts obtained from these sources can be installed on any desktop platform.

Various commercial sites also provide access to common Linux fonts packaged in a platform independent manner. One such site, Font Squirrel, provides vendor neutral access to many common free fonts.