#4621 `\markup \rotate` sometimes rotates entire output (PS backend)

[Simon Albrecht]

:::TeX
\version "2.19.27"

rotated = \markup \rotate #90 "sixteencharactrs"

\rotated
\rotated
\rotated
\rotated

Iff
– the markup string has more than fifteen(!) characters
– and is called more than three times,
the entire output file will be rotated. It happens with all integer multiples of 90 degrees and it’s only the PS backend which is concerned.

[David Kastrup]

I presume that something (ps2pdf or the PDF viewer) counts the number of characters in a straight direction and then guesses the orientation based on a majority decision. In this particular case, it would seem that your "sixteencharactrs" string is competing against the tagline. So try with

\header { tagline = "short" }

for comparison (I'd guess that then fewer characters suffice) and also attach the intermediate PS file so that one can see what kind of orientation information is in there. Hopefully we can figure out how to address that problem, whether by making the orientation more explicit in the PostScript file or by reporting a bug to Ghostscript.

[Simon Albrecht]

New experiments indicate that it needs two more rotated characters than upright:

:::TeX
\version "2.19.27"
\paper { #(set-paper-size "a10") }
\header { tagline = "bi" }
\markup \rotate #90 "four"

Resulting in the following: