# fixed line height

My publisher requires me to use a specific font size and line height:

• regular text: font size: 10pt, line height: 12pt
• footnotes: font size: 8pt, line height 10pt

How do I achieve this in LaTeX? I am using the class scrbook in koma script. The font can be specified as a koma script option:

\documentclass[10pt]{scrbook}


• Hope your preamble itself may work fine with your requirement, what's problem you are facing? – MadyYuvi Oct 17 '17 at 11:04
• you need to be aware that complicated in-line math can cause occasional adjacent lines to be spread apart farther than the nominal distance. this is most frequent with complicated sub/superscripts, fractions, and the like. if you encounter such a problem, do come back with an example showing the specific problem and help can be provided. – barbara beeton Oct 17 '17 at 13:16

With font size option 10pt the regular text size is already 10pt with baseline skip 12pt. So nothing needed for this. The footnote size is also already 8pt but with a baseline skip of 8.5pt instead of the wanted 9pt. You can patch it, to change the baseline skip:

\documentclass[fontsize=10pt]{scrbook}

\usepackage{blindtext}

\usepackage{xpatch}
\xpatchcmd{\footnotesize}{{9.5pt}{10pt}}{}{\patchfailed}

\begin{document}
\blindtext\footnote{\blindtext}
\end{document}


But note: Publishers often use 1/72 inch per point while TeX uses 1 pt = 1/72.27 inch (and 1 bp = 1/72 inch). The difference is very small. Nevertheless it is there. So maybe you want to use (but I would not):

\documentclass[fontsize=10bp]{scrbook}

\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{blindtext}

\makeatletter
\renewcommand*{\footnotesize}{%
\@setfontsize\footnotesize{8bp}{10bp}%
\abovedisplayskip 6bp \@plus2bp \@minus4bp
\abovedisplayshortskip \z@ \@plus1bp
\belowdisplayshortskip 3bp \@plus1bp \@minus2bp
\def\@listi{\leftmargin\leftmargini
\topsep 3bp \@plus1bp \@minus1bp
\parsep 2bp \@plus1bp \@minus1bp
\itemsep \parsep}%
\belowdisplayskip \abovedisplayskip
\let \@listi \@listi@footnotesize \protect \add@extra@listi {ftns}%
}
\makeatother

\begin{document}
\blindtext\footnote{\blindtext}
\end{document}


The reason for using lmodern is: You need a scalable font for really getting font size 10bp and 8bp. The default font is not scalable. So you need at least package fix-cm, but I prefer lmodern.

Instead of putting the new font size definition into the document preamble you could copy scrsize10pt.clo and rename it to mysize10bp.clo. Then edit mysize10bp.clo and change all font sizes like you want. To use this mysize10bp.clo instead of scrsize10pt.clo you have to use

\makeatletter
\def\@fontsizefilebase{mysize}
\makeatother
\documentclass[fontsize=10bp]{scrbook}


If the requirements are for the entire document, I don't see why there should be any problem hacking the normal sizes.

\documentclass[10pt]{scrbook}
\usepackage{lipsum}

\makeatletter
\fontsize{8pt}{10pt}\selectfont%
}
\fontsize{10pt}{12pt}\selectfont%
}
\makeatother

\begin{document}

\lipsum*[1]\footnote{\lipsum*[2]}

\lipsum*[3]\footnote{\lipsum*[4]}

\end{document}


Also of interest might be the grid package.