How to place a number by a sustain bracket to indicate variation in lilypond?

Question

I have the following markup which gives the output below:

\version "2.22.2"
\language "english"

global = {
  \key df \major
  \numericTimeSignature
  \time 2/4
}

right = \fixed c'' {
  \global
  <af, c ef af>8. <bf, c ef af>16~ 16 <c ef> bf, <af, c ef af>~ |
  8. <bf, c ef af>16~ 16 <c ef> bf, <c ef> |
}

left = \fixed c {
  \global
  \clef bass
  <ef, ef>16 <gf, gf> <af c' gf'>8 <gf, gf> <af c' gf'> |
  <f, f> <af c' gf'> <ef, ef>16 <df, df> <c, c>8 |
}

pedal = {
  \set Dynamics.pedalSustainStyle = #'bracket
  8\sustainOn 4\sustainOff 16 16\sustainOn | 16 16\sustainOff 8 8\sustainOn 8\sustainOff |
}

\score {
  \new PianoStaff <<
    \new Staff = "right" \right 
    \new Staff = "left" \left
    \new Dynamics \pedal
  >>
}

I'd like to add a number to the left of each sustain bracket to indicate a variation on the 2nd time the passage is palyed:

The closest I got is by using 8^"1."\sustainOn or 8_"1."\sustainOn, however this places the number above/below the bracket rather than directly before it.

Answer 1

Fret not! Lilypond does allow us to take a lot of control of what to print, easily enabling us to do such annotations:

\version "2.24"
\language "english"

% Return a stencil function that annotates the default stencil with some text.
% If text-from-details is false grob.text is used for text, else grob.details.text
% is used. The staff-dir parameter specifies the direction of the grob relative to
% the staff. This is only used to place indications away from the staff, so it can
% also be interpreted in which direction to move the annotation. If set to #f we
% will attempt to use grob.direction and default to UP.
%
% This function will also make use of grob.details.direction for the X-direction placement
% and grob.details.padding for padding between grob and annotation. Also a manual offset
% can be specified using grob.details.offset
#(define (text-annotate-transformer staff-dir text-from-details)
   (grob-transformer 'stencil
                     (lambda (grob orig)
                       (let* ((det (ly:grob-property grob 'details))
                              (staff-dir (or staff-dir (ly:grob-property grob 'direction UP)))
                              (pad (assoc-get 'padding det 0.3))
                              (dir (assoc-get 'direction det LEFT))
                              (offset (assoc-get 'offset det '(0 . 0)))
                              (text (if text-from-details
                                        (assoc-get 'text det #f)
                                        (ly:grob-property grob 'text #f)))
                              (text-c (or text ""))
                              (m (grob-interpret-markup grob text-c))
                              (m (ly:stencil-aligned-to m X (- dir)))
                              (orig-ext-x (ly:stencil-extent orig X))
                              (ndir (/ (+ dir 1) 2))
                              (orig-refpoint (+ (* ndir (cdr orig-ext-x)) (* (- 1 ndir) (car orig-ext-x))))
                              (m (ly:stencil-translate-axis m orig-refpoint X))
                              (orig-ext-y (ly:stencil-extent orig Y))
                              (orig-refpoint-y (if (< (abs dir) 1)
                                                   (if (< staff-dir 0) (car orig-ext-y) (cdr orig-ext-y))
                                                   (interval-center orig-ext-y)))
                              (m (ly:stencil-aligned-to m Y (if (< (abs dir) 1) (- staff-dir) CENTER)))
                              (m (ly:stencil-translate-axis m orig-refpoint-y Y))
                              (m (ly:stencil-translate m offset))
                              (m (if (< (abs dir) 1)
                                     (ly:stencil-translate-axis m (if (< staff-dir 0) (- pad) pad) Y)
                                     (ly:stencil-translate-axis m (if (< dir 0) (- pad) pad) X))))
                         (if text
                             (ly:stencil-add orig m)
                             orig)))))


\layout {
  \context {
    \Dynamics
    \override PianoPedalBracket.stencil = #(text-annotate-transformer DOWN #f)
    pedalSustainStyle = #'bracket
    \override PianoPedalBracket.font-size = #-2
    \override PianoPedalBracket.font-series = #'bold
  }
}

global = {
  \key df \major
  \numericTimeSignature
  \time 2/4
}

right = \fixed c'' {
  \global
  <af, c ef af>8. <bf, c ef af>16~ 16 <c ef> bf, <af, c ef af>~ |
  8. <bf, c ef af>16~ 16 <c ef> bf, <c ef> |
}

left = \fixed c {
  \global
  \clef bass
  <ef, ef>16 <gf, gf> <af c' gf'>8 <gf, gf> <af c' gf'> |
  <f, f> <af c' gf'> <ef, ef>16 <df, df> <c, c>8 |
}

pedal = {
  8\tweak text "2." \sustainOn 4\sustainOff 16 16\tweak text "1." \sustainOn |
  16 16\sustainOff 8 8\tweak text "2." \sustainOn 8\sustainOff |
}

\score {
  \new PianoStaff <<
    \new Staff = "right" \right 
    \new Staff = "left" \left
    \new Dynamics \pedal
  >>
}


%%% demonstrating details.direction and details.padding parameters
\score {
  \new PianoStaff <<
    \new Staff = "right" \right 
    \new Staff = "left" \left
    \new Dynamics { \override PianoPedalBracket.details.direction = #RIGHT \pedal }
  >>
}

\score {
  \new PianoStaff <<
    \new Staff = "right" \right 
    \new Staff = "left" \left
    \new Dynamics { \override PianoPedalBracket.details.direction = #CENTER \pedal }
  >>
}

\score {
  \new PianoStaff <<
    \new Staff = "right" \right 
    \new Staff = "left" \left
    \new Dynamics { \override PianoPedalBracket.details.direction = #0.3 \pedal }
  >>
}

\score {
  \new PianoStaff <<
    \new Staff = "right" \right 
    \new Staff = "left" \left
    \new Dynamics { \override PianoPedalBracket.details.direction = #CENTER
                    \override PianoPedalBracket.details.padding = #1
                    \pedal }
  >>
}


%%% Use with other grobs:
{
  \override Slur.stencil = #(text-annotate-transformer #f #f)
  \override Slur.details.direction = #CENTER
  c'8\tweak text "(a)" _( d' e' g') c'\tweak text "(b)" ^( d' e' g')
  c'8
  \tweak text "(c)"
  \tweak details.direction #LEFT
  \tweak details.padding #1
  \tweak details.offset #'(0 . -1.5) (
  d' e' f' g' a' b' c'')
}

{
  \override TextScript.stencil = #(text-annotate-transformer #f #t)
  \override TextScript.details.direction = #CENTER
  c
  -\tweak details.text \markup\tiny "(annot)"
  ^"some text"
}