Re: Enhancement: command line option to transpose N halftones up or down

[David Nalesnik]

Hi Michael,


>
> Am 16.03.2015 um 15:02 schrieb Michael Schuerig:
>
>  I've only been using LilyPond for a rather short time, so far mostly for
>> engraving short snippets transposed into several keys for practicing. Of
>> course, the transpose command works nicely for this.
>>
>> However, it made me think of how transposing could be even nicer and now
>> I'm
>> wishing for a command line option to the lilypond command to transpose the
>> engraved document by N halftones up or down. The particular advantage
>> would
>> be that this way the original document doesn't need to be changed in any
>> way
>> in order to transpose it.
>>
>
If you're simply dealing with numbers of semitones, how would you be able
to control whether the output begins on, say, F# versus Gb?

I can imagine something which specifies that the music begin on
such-and-such a pitch.  For that, you could define a simple music
function--which really isn't saving any effort!

%%%
\version "2.19.16"

beginOn =
#(define-music-function (layout props new mus)
   (ly:pitch? ly:music?)
   #{
     \transpose #(ly:make-pitch 0 0) #new
     #mus
   #})

music = { c' d' e' f' }

{
  \music
  \beginOn es'' \music
  \beginOn g \music
}

%%%
I'd have to investigate what would be possible from the command line.

--David