Re: Combine Text/Lyrics with bass figures

[Urs Liska]

Oops, somehow I managed to read only the top half of Lukas' post and
missed the interesting part :-(

Am Freitag, den 26.06.2020, 15:01 +0200 schrieb Lukas-Fabian Moser:
> Hi Urs, hi Moritz,
> 
> > > thanks for the improvements to my code! (I tend to stop thinking 
> > > about it as soon as it works for my case, which always leaves
> > > lots of 
> > > room for improvement.)
> > > 
> > Seems to be the opposite of my approach. I'm always starting to
> > think 
> > in terms of reusability and "packages" right away - leading to
> > working 
> > code much later than would be good ;-)
> When your default working mode is "I need this worksheet tomorrow by
> 9 
> o'clock", the approach of using the first sort-of viable solution 
> becomes much more tempting ;-).
> 
> > > (2) There might also be cases where you have more that one row of
> > > arabic
> > > numbers to indicate other options. My first intention here would
> > > be to have a
> > > single layer for every key, that is used in the analysis. If
> > > there’s an option
> > > to hide the layer where it is not used.
> > Each layer is a Lyrics or FiguredBass context, [...]
> 
> That's exactly what occurred to me over lunch: Everything we talked 
> about concerning spacing just expresses the fact that scale degrees
> and 
> bass figures should behave as if they were independent contexts (one 
> FiguredBass, one Lyrics).
> 
> So let's scrap the idea of inserting scale degrees artificially into 
> bass figures where they do not belong!
> 
> Hence:
> 
> \version "2.20.0"
> 
> #(define (scale-degree degree)
>        (if (eqv? degree 0)
>            (markup #:null)
>            (markup #:circle #:small #:number (number->string
> degree))))
> 
> #(define (bass-degree? obj)
>     "A bass degree is either a number between 1 and 7 or 0 (eqv. to
> nothing)!"
>     (and (integer? obj) (> 8 obj) (< -1 obj)))
> 
> #(define (event-chord? obj)
>     (and (ly:music? obj) (music-is-of-type? obj 'event-chord)))
> 
> 
> #(define (figure-signature? obj)
>     "A figure signature is either an EventChord music or a duration."
>     (or
>      (event-chord? obj)
>      (ly:duration? obj)))
> 
> duration-from-event-chord =
> #(define-scheme-function (chord) (event-chord?)
>     (let ((els (ly:music-property chord 'elements)))
>       (ly:music-property (first els) 'duration)))
> 
> scaledeg =
> #(define-music-function (num signature) ((bass-degree? 0) figure-
> signature?)
>     (let ((dur (if (ly:duration? signature)
>                     signature
>                     (duration-from-event-chord signature))))
>       #{
>         <<
>         #(if (ly:music? signature)
>              signature
>              #{ s $signature #})
>         \context Lyrics = "scaleDegrees" \lyricmode
>         {
>           \markup { #(scale-degree num) } $dur
>         }
>         >>
>       #}))
> 
> 
> 
> <<
>    \new Staff {
>      \time 3/4
>      \clef bass
>      c4 d e f2 g4 as2^"or g sharp?" a4 b4 c'4 % Morgenlich leuchtend
> ...
>    }
>    \figures \with { \override 
> VerticalAxisGroup.nonstaff-nonstaff-spacing.padding = 1 } {
>      \scaledeg 1 4
>      \scaledeg 2 <4 3>4
>      \scaledeg 3 <6>4
>      \scaledeg 4 <7>4
>      \scaledeg 0 <6>
>      \scaledeg 5 4
>      \scaledeg 6 <6>2
>      \scaledeg 6 <6>4
>      \scaledeg 7 <6 5>4
>      \scaledeg 1 4
>    }
>    \new Lyrics = "scaleDegrees" { \skip 1*8 }
>  >>
> 
> 
> Of course this is just proof-of-concept: 

It looks like this is very extensible, and I'll definitely have a
closer look at it.

> The Lyrics context should be 
> created (and kept alive) automatically ... or, even better: it should
> be 
> user-settable with an interface like:
> 
> \figures {
> 
>    \inject-scaledegrees-into-context "scaleDegrees"
> 
>    ...
> 
> }
> 
> which would enable all sorts of vertical configuration.

This can be done by defining the figures in a variable, say, figs and
then doing something like

makeDegrees = {
  <<
    \new FiguredBass \with {
      \override VerticalAxisGroup.nonstaff-nonstaff-spacing.padding = 1
    } \figs
    \new Lyrics = "scaleDegrees" { #(skip-of-length figs) }
  >>
}

In the score definition we use \makeDegrees instead of explicitly
creating the contexts.

I think I'll really investigate how this can nicely be integrated in an
anlysis.harmony package.

BestUrs

> 
> Best
> Lukas
>