Dear Peter, Thank you for raising this question.
On Tue, 26 May 2026, Peter Payzant wrote: > how to create the "breve = dotted breve" string (?), and how to position > the result above the staff, centred on the bar line. It is a good one for us to address, as I am sure that at some point I myself will need to engrave a mensuration change in an edition of a Renaissance mass or motet! Below please find my draft solution. I hope that this is helpful. One limitation of my current solution: Ideally, we’d like to set the horizontal alignment point of the custom rehearsal mark to be the centre of the equals sign. That would be more elegant than the current \once \override Score.RehearsalMark.self-alignment-X = #-0.12 (an approximate value that I found through trial and error whilst zooming in). Kieren helped me do something similar for self-alignment-X of lyric syllables for this snippet: https://wiki.lilypond.community/wiki/Aligning_lyrics_based_on_vowels. I haven’t figured out yet how to adapt that snippet’s approach for what we’re discussing here. If anyone reading this email can share a solution for automagically X-aligning the mensuration-change RehearsalMark using the center of the equals sign, I’d be very grateful! I’ll volunteer to make a snippet for the Wiki, demonstrating that solution. Cheers, Gabriel [image: image.png] %%% SNIPPET BEGINS \version "2.27.0" simpleBreve = \markup { \override #'(style . baroque) \note { \breve } #UP % (stem direction) } dottedBreve = \markup { \override #'(style . baroque) \note { \breve. } #UP % (stem direction) } equals = \markup { \char ##x003D % https://en.wikipedia.org/wiki/Mathematical_operators_and_symbols_in_Unicode } myMensurationChange = \markup \vcenter { \simpleBreve % To add some horizontal space (optional): % \null \equals % To add some horizontal space (optional): % \null \dottedBreve } % On \vcenter, see % https://lilypond.org/doc/v2.27/Documentation/notation/text-markup-commands#index-_005cvcenter \fixed c' { d1 | % Manual override to align % the center of the equals sign % to the bar line: \once \override Score.RehearsalMark.self-alignment-X = #-0.12 \mark \myMensurationChange \time 3/2 a1. | } %%% SNIPPET ENDS
