Use \normalsize with \SetWatermarkFontSize

draftwatermarkfontsize

I use a package that generates watermarks, its name is draftwatermark. The package offers options or commands to set its properties. One of the properties is the size of the watermark text in units of length (e.g. 12pt). However, I don't want to set the length with an explicit value (e.g. 12pt), but I want to use the document's \normalsize length instead. I wrote:

\SetWatermarkFontSize{\normalsize}

But it doesn't work. How can I set this value to match the document's \normalsize?

Best Answer

\normalsize is an internal command that sets the font size to either 10pt, 11pt or 12pt (plus a few additional things like \abovedisplayskip) etc.

\SetWatermarkFontSize, on the other hand, expects a value, not a command. If you don't want to use something like 12pt (why not?), you can use a relative value, like 0.25\paperwidth or, if you want to base it on the font size, something like 1em.

\SetWatermarkFontSize{1.15em}

Related Solutions

[Tex/LaTex] Determine height and depth of letters relative to the font size

The "ex height" is a length that has a weak relation to the height of an "x"; for example in cmr10 the two are equal, while in TeX Gyre Pagella they don't: an "x" is 4.42pt high an 1ex is 4.845pt.

It's generally impossible to predict the height of the uppercase letters based on the "type size", as barbara beeton underlines in her comment. One should also remember that TeX know only the "bounding box" of the characters, which often protrude from it: for example the upper vertex of an A can overshoot a bit. But for the problem of adapting a built symbol to the general shape of a font this overshoot is not important.

The value of 1ex is font dependent and resides in "fontdimen 5" and is directly available as \fontdimen5\font:

\dimen0=\fontdimen5\font
\dimen0=1ex

are equivalent assignments (which are immediately translated in points).

With e-TeX it's not necessary to box a character in order to measure it:

\dimen0=\fontcharht\font`B
\dimen2=\fontchardp\font`q

which in LaTeX-speak are

\setlength{\dimen0}{\fontcharht\font`B}
\setlength{\dimen2}{\fontchardp\font`q}

assign to \dimen0 and \dimen2 the height of an uppercase B and the depth of a lowercase q in the current font. There are also \fontcharwd and \fontcharic for retrieving the width and the italic correction. Again, these lengths are those of the bounding box, not necessarily of the character itself.

[Tex/LaTex] How to choose font size given the paper size

The problem is not the font size nor the paper size, but the numbers of characters per line.

As noted in others answers, around the 65 ± 15 characters is considered a reasonable cut-off regardless the document type and even the font size.

When line of text are too long, your eyes will have a hard time focusing on the text. Its difficult find where the next line starts, specially in large paragraphs. Think in a landscape A0 poster with a single column of text ...

If the line
is too short
break the reader
rhythm, since
the eyes will
have to travel
back too often.
This is so
annoying that
dancing eyes
can skip
some words.

You can roughly estimate the Average number of characters in one line. If you find that this number is out of a reasonable range, your options are basically:

Modify the margins. People are often obsessed with layouts that fit in mathematical ratios (golden ratio of 1.618:1, etc), geometrical rules, traditional styles, etc., but IMHO, the best way to judge a layout is your eyes, not any arbitrary type of complex algebra. Here you must consider mainly two factors:

a. Readability. Let these margins take the document in your hands without putting your fingers on the text? Do you see the text beside the inner margins of the book in a true 2D plane or in the border of a black hole? The part of the screen around the PDF is distracting you?

b. Appearance. The margin of a text, like a picture frame, is a ornament that highlight the content. The ornament depend of the text. A luxury book need big margins, but not a shopping list.
Modify the font size. Try to stay in the 10-12pt range as far as possible, but the important point is a comfortable viewing at about one arm's length (or more for a poster). In any case must be still easily readable, i.e, even if the line is less than 50 characters, do not use a 8pt characters for readers over 40 years. People with presbyopia will curse you for it. A very big font is harder to read too.
Use two or more columns. For any bigger pager size than a A4 paper is really a must. Magazines and newspapers always use multiple-column layouts for this reason, never single blocks of text with one inch margin or so. Even for articles in A4 with a 10pt, IMHO is more pleasant two columns with reasonable smaller margins than a single column with the default margins.

Best Answer

Related Solutions

[Tex/LaTex] Determine height and depth of letters relative to the font size

[Tex/LaTex] How to choose font size given the paper size

Related Question