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diff --git a/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-overfull.html b/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-overfull.html deleted file mode 100644 index b518a27bc39..00000000000 --- a/Master/texmf-doc/doc/english/FAQ-en/html/FAQ-overfull.html +++ /dev/null @@ -1,133 +0,0 @@ -<head> -<title>UK TeX FAQ -- question label overfull</title> -</head><body> -<h3>(La)TeX makes overfull lines</h3> -<p/>When TeX is building a paragraph, it can make several attempts to -get the line-breaking right; on each attempt it runs the same -algorithm, but gives it different parameters. You can affect the way -TeX’s line breaking works by adjusting the parameters: this answer -deals with the “tolerance” and stretchability parameters. The other -vital ‘parameter’ is the set of hyphenations to be applied: see -“<a href="FAQ-nohyph.html">my words aren’t being hyphenated</a>” -(and the questions it references) for advice. -<p/>If you’re getting an undesired “overfull box”, what has happened is -that TeX has given up: the parameters you gave it don’t allow it to -produce a result that <em>doesn’t</em> overfill. In this circumstance, -Knuth decided the best thing to do was to produce a warning, and to -allow the user to solve the problem. (The alternative, silently to go -beyond the envelope of “good taste” defined for this run of TeX, -would be distasteful to any discerning typographer.) The user can -almost always address the problem by rewriting the text that’s -provoking the problem — but that’s not always possible, and in some -cases it’s impossible to solve the problem without adjusting the -parameters. This answer discusses the approaches one might take to -resolution of the problem, on the assumption that you’ve got the -hyphenation correct. -<p/>The simplest case is where a ‘small’ word fails to break at the end of -a line; pushing the entire word to a new line isn’t going to make much -difference, but it might make things just bad enough that TeX won’t -do it by default. In such a case on can <em>try</em> the LaTeX -<code>\</code><code>linebreak</code> command: it may solve the problem, and if it does, it -will save an awful lot of fiddling. Otherwise, one needs to adjust -parameters: to do that we need to recap the details of TeX’s line -breaking mechanisms. -<p/>TeX’s first attempt at breaking lines is performed without even -trying hyphenation: TeX sets its “tolerance” of line breaking -oddities to the internal value <code>\</code><code>pretolerance</code>, and sees what -happens. If it can’t get an acceptable break, TeX adds the -hyphenation points allowed by the current patterns, and tries again -using the internal <code>\</code><code>tolerance</code> value. If this pass also fails, and -the internal <code>\</code><code>emergencystretch</code> value is positive, TeX will try -a pass that allows <code>\</code><code>emergencystretch</code> worth of extra stretchability -to the spaces in each line. -<p/>In principle, therefore, there are three parameters (other than -hyphenation) that you can change: <code>\</code><code>pretolerance</code>, <code>\</code><code>tolerance</code> -and <code>\</code><code>emergencystretch</code>. Both the <code>tolerance</code> values are -simple numbers, and should be set by TeX primitive count -assignment — for example -<blockquote> -<pre> -\pretolerance=150 -</pre> -</blockquote><p> -For both, an “infinite” tolerance is represented by the value -<code>10</code><code>000</code>, but infinite tolerance is rarely -appropriate, since it can lead to very bad line breaks indeed. -<p/><code>\</code><code>emergencystretch</code> is a TeX-internal ‘dimen’ register, and can -be set as normal for dimens in Plain TeX; in LaTeX, use -<code>\</code><code>setlength</code> — for example: -<blockquote> -<pre> -\setlength{\emergencystretch}{3em} -</pre> -</blockquote><p> -<p/>The choice of method has time implications — each of the -passes takes time, so adding a pass (by changing -<code>\</code><code>emergencystretch</code>) is less desirable than suppressing one (by -changing <code>\</code><code>pretolerance</code>). However, it’s unusual nowadays to find a -computer that’s slow enough that the extra passes are really -troublesome. -<p/>In practice, <code>\</code><code>pretolerance</code> is rarely used other than to manipulate -the use of hyphenation; Plain TeX and LaTeX both set its value -to <code>100</code>. To suppress the first scan of paragraphs, set -<code>\</code><code>pretolerance</code> to <code>-1</code>. -<p/><code>\</code><code>tolerance</code> is often a good method for adjusting spacing; -Plain TeX and LaTeX both set its value to <code>200</code>. LaTeX’s -<code>\</code><code>sloppy</code> command sets it to <code>9999</code>, as does the -<code>sloppypar</code> environment. This value is the largest -available, this side of infinity, and can allow pretty poor-looking -breaks (this author rarely uses <code>\</code><code>sloppy</code> “bare”, though he does -occasionally use <code>sloppypar</code> — that way, the change of -<code>\</code><code>tolerance</code> is confined to the environment). More satisfactory is -to make small changes to <code>\</code><code>tolerance</code>, incrementally, and then to look to -see how the change affects the result; very small increases can often -do what’s necessary. Remember that <code>\</code><code>tolerance</code> is a paragraph -parameter, so you need to ensure it’s actually applied — see -“<a href="FAQ-paraparam.html">ignoring paragraph parameters</a>”. -LaTeX users could use an environment like: -<blockquote> -<pre> -\newenvironment{tolerant}[1]{% - \par\tolerance=#1\relax -}{% - \par -} -</pre> -</blockquote><p> -enclosing entire paragraphs (or set of paragraphs) in it. -<p/>The value of <code>\</code><code>emergencystretch</code> is added to the assumed -stretchability of each line of a paragraph, in a further run of the -paragraph formatter in case that the paragraph can’t be made to look -right any other way. (The extra scan happens if -<code>\</code><code>emergencystretch>0pt</code> — if it’s zero or negative, no gain -could be had from rerunning the paragraph setter.) The example above -set it to <code>3em</code>; the Computer Modern fonts ordinarily fit three -space skips to the <code>em</code>, so the change would allow anything up -to the equivalent of nine extra spaces in each line. In a line with -lots of spaces, this could be reasonable, but with (say) only three -spaces on the line, each could stretch to four times its natural -width. It is therefore clear that <code>\</code><code>emergencystretch</code> needs to be -treated with a degree of caution. -<p/>More subtle (but more tricky to manage) are the microtypographic -extensions provided by PDFTeX. Since PDFTeX is the default -‘engine’ for LaTeX and ConTeXt work in all distributions, -nowadays, the extensions are available to all. There are two -extensions, margin kerning and font expansion; margin kerning only -affects the visual effect of the typeset page, and has little effect -on the ability of the paragraph setter to “get things right”. -Font expansion works like a subtler version of the trick that -<code>\</code><code>emergencystretch</code> plays: PDFTeX ‘knows’ that your current font -may be stretched (or shrunk) to a certain extent, and will do that -“on the fly” to optimise the setting of a paragraph. This is a -powerful tool in the armoury of the typesetter. -<p/>As mentioned above, the microtypographic extensions are tricky beasts -to control; however, the <i>microtype</i> package relieves the user -of the tedious work of specifying how to perform margin adjustments -and how much to scale each font ... for the fonts the package -knows about; it’s a good tool, and users who can take on the -specification of adjustments for yet more fonts are always welcome. -<dl> -<dt><tt><i>microtype.sty</i></tt><dd><a href="ftp://cam.ctan.org/tex-archive/macros/latex/contrib/microtype.zip">macros/latex/contrib/microtype</a> (<a href="ftp://cam.ctan.org/tex-archive/macros/latex/contrib/microtype.tar.gz">gzipped tar</a>, <a href="http://www.tex.ac.uk/tex-archive/macros/latex/contrib/microtype/">browse</a>) -</dl> -<p/><p>This question on the Web: <a href="http://www.tex.ac.uk/cgi-bin/texfaq2html?label=overfull">http://www.tex.ac.uk/cgi-bin/texfaq2html?label=overfull</a> -</body> |