Re: Tight spacing in mensural notation (was: Re: Cadenza Senza Tempo Problem)

[Thomas Morley]

Am Mi., 30. Okt. 2019 um 19:44 Uhr schrieb Graham King
<address@hidden>:

> Harm, I'm afraid I'm struggling with "#(ly:make-moment -3)"
>
> The NR[2] shows four arguments to ly:make-moment, describes two of them, and 
> then speaks a little obtusely of the _second_ argument to ly:make-moment 
> being possibly negative, and I can't find any examples of a negative first 
> (and only) argument online.  Most examples seem to use one argument, a 
> positive rational, which I think I do understand.
>
> Where does this syntax come from and what does it mean?
> And why did you choose -3 ?
>
> TIA
> -- Graham
>
> [2] 
> http://lilypond.org/doc/v2.19/Documentation/notation/scheme-functions#index-ly_003amake_002dmoment
>

I intended to set common-shortest-duration to the length of a maxima,
to get tight spacing, see IR
(Similiar for base-shortest-duration, although this may be superfluous.)
And I confused ly:make-moment and ly:make-duration :(

Though the duration-log of a maxima is -3, it's length is #<Mom 8>

See:
\new MensuralStaff {
  \compressFullBarRests
  \applyMusic
    #(lambda (mus)
      (ly:music-set-property! mus 'duration (ly:make-duration -3))
      (format #t "\n\tLength of music: ~a\n\tDuration of music: ~a"
        (ly:music-length mus)
        (ly:music-property mus 'duration))
      mus)
  b
}

=>

    Length of music: #<Mom 8>
    Duration of music: #<Duration log = -3 >


So you better change in my proposal common-shortest-duration to:
\override SpacingSpanner.common-shortest-duration = #(ly:make-moment 8)

Cheers,
  Harm