Use \normalsize with \SetWatermarkFontSize

Question

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?

Answer 1

\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}