Re: Banjo tablature stem length for beamed stems?

[Thomas Morley]

2015-03-21 0:24 GMT+01:00 Thomas Morley <address@hidden>:
> 2015-03-20 17:21 GMT+01:00 address@hidden
> <address@hidden>:
>> I’m working on some banjo tablature and I’d like to change the stem length 
>> for beamed stems when 2 non-adjacent strings are played together. I can use 
>> \override-s to lengthen and shift the stems of unbeamed notes. How can I 
>> change the length of beamed stems? It seems like beamed-lengths might hold 
>> the answer, but I haven’t figured out how to apply it or what the numbers 
>> mean. See the minimal example below.
>> Thanks,
>> Holland
>>
>> ************
>>
>> \version "2.18.0"
>>
>> \new TabStaff {
>>         \set TabStaff.instrumentName = "Banjo"
>>         \set TabStaff.tablatureFormat = #fret-number-tablature-format-banjo
>>         \set TabStaff.stringTunings = #banjo-open-g-tuning %gDGBD
>>         \tabFullNotation
>>         \numericTimeSignature
>>         \clef moderntab
>>          \relative c'   {
>> \time 4/4
>>
>> g8   < g'\5 d >8
>> %how can I make this stem longer, like the unbeamed stem after it?
>>                r2.     |
>>
>> g,8
>>
>>  \once \override Stem.length = #12 % make the stem longer
>>   \once     \override Stem.Y-offset = #7 % moves the stem up
>>   \once \override Stem.Y-extent = #'(-7.0 . 0.0)
>> %moves the flag to the end of the moved stem
>>
>>               < g'\5 d >8
>>
>>
>>   } % end of banjo notes
>>   } % end of banjo voice
>>
>>
>> _______________________________________________
>> lilypond-user mailing list
>> address@hidden
>> https://lists.gnu.org/mailman/listinfo/lilypond-user
>
> How about my coding here:
> http://lilypond.1069038.n5.nabble.com/Stem-length-at-a-fixed-height-td172661.html#a172677
>
> Cheers,
>   Harm

More elaborated:

\version "2.19.16"

equal-tab-staff-stems =
#(define-music-function (parser location avoid-intermediate-stems? val)
  ((boolean? #f) number?)
  "
   Prints all Stems ending at the same height.
   \\tabFullNotation has to be set.
   Printing intermediate stems, connecting TabNoteHeads in chords, is optional,
   default is to print them.
  "
  #{

    %% We set 'stem-attachment to '(0 . 0), but widen the extent of the
    %% TabNoteHead in Y-direction
    %% Otherwise the gap between TabNoteHead and Stem is inconsistent
    \override TabNoteHead.stem-attachment = #'(0 . 0)
    \override TabNoteHead.stencil =
    #(lambda (grob)
      (let ((default-stil (tab-note-head::print grob)))
        (ly:make-stencil
          (ly:stencil-expr default-stil)
          (ly:stencil-extent default-stil X)
          (interval-widen (ly:stencil-extent default-stil Y) 0.2))))

    %% Printing intermediate Stems is made optional, default is to print them
    \override Stem.avoid-note-head = #avoid-intermediate-stems?

    %% Lowering Stem.layer to let the TabNoteHead whiteout them
    \override Stem.layer = -100

    \override Stem.direction =
      #(lambda (grob)
        (if (negative? val)
            DOWN
            UP))

    %% Calculate unbeamed Stem.length to let them end according to
    %% @var{val}
    \override Stem.after-line-breaking =
      #(lambda (grob)
        (let* ((stem-begin-pos (ly:grob-property grob 'stem-begin-position)))
        ;; the override for Beam.positions counts from staff-position 0
        ;; thus we need to go there for the (unbeamed) stem-length as well
        ;; beam-thickness is taken from engraver-init.ly:
        (ly:grob-set-property! grob
          'length
          (+ (if (negative? val)
                 stem-begin-pos
                 (- stem-begin-pos))
             (* (abs val) 2)
             ;; beam-thickness:
             0.32))))

    %% Set Beam.positions to @var{val}, resulting in new stem-lengths
    \override Beam.positions = #(cons val val)
  #})

my-banjo-tab-settings =
  \with {
    instrumentName = "Banjo"
    tablatureFormat = #fret-number-tablature-format-banjo
    stringTunings = #banjo-open-g-tuning %gDGBD
    \tabFullNotation
    \equal-tab-staff-stems #5
  }


\new TabStaff \my-banjo-tab-settings
  \relative c' {
    \numericTimeSignature
    \clef moderntab

    g8 < g'\5 d >8 r2. |
    g,8 <g'\5 d, b' d > g\5 d, g \noBeam b d4 |
  } % end of banjo notes


HTH,
  Harm