How to achieve the equivalent of the MS Word "1.15" Line Spacing option with the LaTeX 'book' document class?

Question

I want to set 1.15 line spacing (as there is option in microsoft word) for the entire content in book class. I referred to some question on this site. I found the following.

\linespread{1.667} sets double space (2.0 line spacing as in microsoft word).

\linespread{1.25} sets one and half space (1.5 line spacing as in microsoft word).

How to set line spacing 1.15 as required in microsoft word? Would the command \linespread{0.958} set 1.15 line spacing as in microsoft word?

I also have another query. If in a class file it is set as \AtBeginDocument{\linespread{0.958}} will it affect the entire content in book? Should I use it before or after \LoadClass{book}?

Answer 1

Don't modify the low-level parameter \linespread directly, as doing so will also affect how material in footnotes and tables is spaced. (Of course, if your document has neither footnotes nor tables, you don't have to worry about this point, do you?) Instead, I suggest you load the setspace package and issue various \setstretch{xx} directives, where "xx" is a stretch or shrinkage factor; a value of 1.0 is the default.

I've performed a number of side by side tests with MS Word and LaTeX to determine which arguments of \setstretch correspond to the 1.15, 1.5, and 2.0 stretch settings of MS Word. All tests use "A4" as the default paper size. The font is Times Roman, the font size is 12pt in LaTeX and 12bp ("big points", aka "Adobe points") in Word. The LaTeX document class is book, and the margin width is 2.5cm on all four sides in both test documents.

The LaTeX test document is as follows:

\documentclass[12pt]{book}
\usepackage[a4paper,margin=2.5cm,showframe]{geometry}
\usepackage{newtxtext,newtxmath} % Times Roman
\usepackage{setspace}

\input blob

\begin{document}
\raggedright

\setstretch{1.0}   % no stretching or shrinking 
\blob

\cleardoublepage
\setstretch{1.2}  % corresponds to Word's "1.15" setting
\blob

\cleardoublepage
\setstretch{1.5}   % corresponds to Word's "1.5" setting
\blob

\cleardoublepage
\setstretch{2.0}   % corresponds to Word's "Double" setting
\blob

\end{document}

The file blob.tex has the following contents:

\newcommand{\blob}{\noindent
aöfjasdlökfjasöl dsjfasölkjfa sdajfasölk asdljfaölk aöfjasdlökfjasöl dsjfasölkjfa sdajfasölk asdljfaölk aöfjasdlökfjasöl dsjfasölkjfa sdajfasölk asdljfaölk aöfjasdlökfjasöl dsjfasölkjfa sdajfasölk asdljfaölk aöfjasdlökfjasöl dsjfasölkjfa sdajfasölk asdljfaölk aöfjasdlökfjasöl dsjfasölkjfa sdajfasölk asdljfaölk aöfjasdlökfjasöl dsjfasölkjfa sdajfasölk asdljfaölk1
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}

If you have both a LaTeX and an MS Word installation at hand, you may verify for yourself that the MS Word line spacing options "Single", "1.5 Lines", "Double", and "Multiple - 1.15" correspond to \setstretch{1.0}, \setstretch{1.5}, \setstretch{2.0}, and \setstretch{1.2}. Yes, that's 1.2, not 1.15, in the argument of the final \setstretch directive.

In case you're curious, the 1.0, 1.2, 1.5, and 2.0 stretch factors serve to place 48, 40, 32, and 24 lines of text per page in the test document defined above. (The stretch factor 1.15 would place 34, not 32, lines on the first page.)

Interestingly, the stretch factors of 1.5 and 2.0 do not correspond to the onehalfspacing and doublespacing options of the setspace package; the latter two options actually correspond to stretch factors of 1.241 and 1.655 if the main document font size is 12pt. Somewhat reassuringly, though, the singlespacing package option does correspond to a stretch factor of 1.0.

Finally, a couple of screenshots, for (a) MS Word with line spacing option 1.15 and (b) LaTeX with \setstretch{1.2}.

Observe that both documents have 32 lines of text on the left and 8 lines of text on the right.

Answer 2

This is general information, rather than an answer to the question. But it is definitely worth knowing, for anyone who is writing a book (in any document class) and is familiar with a word processor.

Most word processors assume that the glyph metrics (size and space of the character drawings) obey this limitation: The distance from lowest point on any glyph, to the highest point on any other glyph, does not exceed 1.2 times the font size. This includes modifiers such as diacriticals.

For example, suppose that the lowest point is the bottom of lowercase "y", and the highest point is the top of uppercase "Aacute" or "Aring". This is typical for Western language fonts. If the font size is F (measured in pt or bp or anything else), then the distance from bottom to top should not exceed 1.2F.

That allows the word processor (or TeX) to use a minimum line skip of 1.2F, confident that there will be no clash between low and high points of the characters.

Most fonts are designed with this limitation in mind. A few are not.

For English writers, or anyone not using such things as accented uppercase letters, it is possible to have line skip lower than 1.2F. Even with accented uppercase, there is a low chance that such a letter will happen to be directly underneath a character with greatest descender, so it is sometimes possible to use less than 1.2F. But for languages with stacked diacritical marks, 1.2F is not enough.

If not enough line skip is provided, then some lines will move apart. This may look unsightly.

I am not certain whether to original question referred to line skip of 1.15F, or to 1.15x1.2F, or something else.

Books intended for causal reading (fiction) often use more than the minimum line skip.