Is it possible to tell (La)TeX to adjust the kerning of a specific character combination? For example, suppose I want !! to be typeset as !\kern 1.2pt!, just like ff is automatically turned into a ligature, or -- is converted to an en-dash. I know I could create a command for this combination—I am asking for a way to just type !! and have it use my desired kerning.
[Tex/LaTex] way to adjust kerning for a specific character combination
kerning
Related Solutions
The usual negative space commands such as \! (See Large negative spaces )from the math-mode can be put before the exponent to shift it to the left.
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\[
\left(\frac{2\pi}{T}\right)^{\frac{8}{3}}
\]
\[
\left(\frac{2\pi}{T}\right)^{\!\frac{8}{3}}
\]
\[
\left(\frac{2\pi}{T}\right)^{\!\!\frac{8}{3}}
\]
\end{document}
In typophile.com forum, user dudefellow kindly posted the following nice idea which is kind of what I'm trying to get from my question. Hence, I'm posting it as a demonstration of what I'm after.
I would appreciate if we can limit the discussion to such propositions. It's more of a design question rather than the linguistic part as I've tried to clarify in the edit of my question.
More ideas about the ligature (thanks to dudefellow for the Armenian twist):
Best Answer
Adjusting font kerning
If you need to adjust the kerning within a font, the short answers are:
No, not from within TeX.
Yes, if you're willing to create a virtual font.
Yes, if you're able to edit the font with fontforge (OpenType fonts only, for use in XeTeX or LuaTeX).
Yes, if you're using LuaTeX and OpenType fonts; see §11 of the fontspec manual: ‘OpenType font feature files’.
I've only experience in options 1 and 4.
XeTeX's interchartoks
XeTeX offers a feature known as ‘interchartoks’ that allows tokens to be inserted automatically between characters of different ‘class’. This feature was added to facilitate, say, automatic font and language switching between two different scripts (e.g., Japanese to Arabic).
This feature can be used to add kerning between characters, as shown in Philipp's answer. (As well as between
!!, you might also choose to adjust spacing around:for French typography, say.) As an example, if this feature is used then when XeTeX comes across!!in the input, it will interpret it as!\exclamkern!instead. Any kerning that happens there will independent of the current font, which is generally not going to be appropriate for changing the kerning between letters. But for very specific use cases this technique is suitable for minor adjustments.