# Font Switching

## Introduction

This is a wikified version of this Tugboat article.

In this article I will discuss how to use the various font styles in ConTeXt. Fonts are one of the most complicated parts of TeX. Fortunately, the macro developers take care of the dirty stuff, and most of the user interface is clean. Nevertheless, understanding the various options of the user interface can be intimidating. As a beginner, one does not want to know all the nitty-gritty details, but just the basic features. We hope to present these in this article.

In ConTeXt there are four ways to switch fonts:

I will briefly explain each of these.

## Font styles

There are three types of font families: serif, sans serif, and teletype. To switch between these families, use \rm for serif, \ss for sans serif, and \tt for teletype.

Each of these families come in different styles: upright, bold, italic, slanted, bold-italic, bold-slanted, and small-capped. To switch to a different style, use \tf for upright, \bf for bold, \it for italic, \sl for slanted, \bi for bold-italic, \bs for bold-slanted, and \sc for small-capped.

You can generally combine font families and font styles, so if you want to switch to bold sans serif, you can use either \bf\ss or \ss\bf.

There is a font switch \em to 'emphasize' text. This is somewhat special: it does automatic italic correction and changes the style depending on the current font style. For example, if the current font style is upright, \em switches to slanted; and if the current font style is slanted, \em switches to upright.

ConTeXt uses the Latin Modern fonts by default; these fonts look similar to the original Computer Modern fonts, but have a much larger character repertoire. As it happens, in the Latin Modern (and Computer Modern) fonts, the slanted font does not stand out from the upright font enough for some tastes; so, many people prefer to use the italic font for emphasis. To do that use

\definebodyfontenvironment[default][em=italic]


A font switch remains valid for the rest of the group. So, if you want to temporarily switch to a different font, use the font style command inside a group. The easiest way to start a group is to enclose the text within braces (also called curly brackets), for example

This is serif text
{\ss This is sans serif}
{\tt and this is typewriter}


which gives (notice the braces in the above lines)

## Font sizes

Occasionally one needs to change the font size. ConTeXt provides two series of commands for that. To increase the font you can use \tfa to scale the font size by a factor of 1.2, \tfb to scale by a factor of (1.2)^2 = 1.44, \tfc to scale by (1.2)^3 = 1.728 and \tfd to scale by (1.2)^4 = 2.074.

To decrease the font size, you can use \tfx to scale the font by a factor of 0.8 and \tfxx to scale by a factor of 0.6. The scale factors can be a function of the current font size and can be changed by \definebodyfontenvironment.

For example, if you want \tfa to be equal to 12pt when you are using 10pt font, and be equal to 14pt when you are using 11pt font, then add

\definebodyfontenvironment [10pt] [a=12pt]
\definebodyfontenvironment [11pt] [a=14pt]


\definebodyfontenvironment is described in detail in the ConTeXt manual and the font-ini.tex source file.

Font size can be combined with font styles. As a shortcut, you can use \bfa to get bold font scaled by 1.2, \bfx to get a bold font scaled by 0.8 and similar commands for other font styles.

These font size switches are meant for changing the font size of a few words: they do not change the interline spacing and math font sizes. So, if you want to change the font size of an entire paragraph, use \switchtobodyfont described below in Complete Font Change. However, it is fine to use them as style directives in setup commands, that is, using them as an option for style=... in any setup command that accepts style option.

## Alternative font styles

While learning a document markup language like ConTeXt, it can be hard to remember all the commands. ConTeXt provides easy to remember alternative font styles. So for bold you can use \bold, for italic you can use \italic, for slanted you can use \slanted, and so on. You can probably guess what the following do:

In addition, the commands \smallbodyfont and \bigbodyfont can be used to change the font size.

These alternative font styles are pretty smart. You can either use them as font style switches inside a group, or as a font changing command that takes an argument. For example,

This is {\bold bold} and so is \bold{this}.


These alternative font styles can also be used for all style=... options, and while using them as style options, you can just give the command name, for example:

\setuphead[section][style=bold]


## Complete font change

If you need to change to a different font size and take care of interline spacing, you can use \switchtobodyfont. For example, to switch to 12pt you can use \switchtobodyfont[12pt].

ConTeXt provides two relative sizes, called 'big' and 'small'. So, to go to a bigger font size use \switchtobodyfont[big] and to use a smaller font size use \switchtobodyfont[small]. The exact size used for big and small can be set using \definebodyfontenvironment.

The \setupbodyfont command accepts all the same arguments as \switchtobodyfont. The difference between the two is that \setupbodyfont also changes the font for headers, footers and other page markings, while \switchtobodyfont does not. So you should use \setupbodyfont for global font definitions to apply to the whole document, and \switchtobodyfont for local font changes. The effect of \switchtobodyfont can be localized within a group as usual.

## Different typefaces

So far we have discussed style and size changes within a given typeface family. If you want to use a different typeface altogether, such as Times or Palatino, the Pragma web site has recipes covering all the commonly available typefaces [1], while a separate manual describes how to write support for new typefaces [2].

The recipes as given work with the standalone ConTeXt distribution, but not with TeX Live et al. [3] explains why CONTEXT uses separate font metrics, and gives some differences between the sets. To use the recipes with other distributions, try adding one of \usetypescript[berry][ec] or \usetypescript[adobekb][ec].

## Conclusion

There are many other ways of choosing font styles in ConTeXt. If these basic styles do not satisfy your needs, have a look at the manual, or ask on the ConTeXt Mailing Lists.