New for specialist notation

• For consistency with other ancient clefs, five new mensural clefs are available: "mensural-f2", "mensural-f3", "mensural-f4" (same as "mensural-f"), "mensural-f5", "mensural-g1", "mensural-g2" (same as "mensural-g").
• The default time signature and accidental style in a PetrucciStaff context is now the same as in MensuralStaff.
• White mensural ligatures now support some rare ligatures (semibreves alone or in the middle), and allow tweaks to show some non-necessary stems.

  \score {
    \relative {
      \set Score.timing = ##f
      \set Score.measureBarType = #'()
      \override NoteHead.style = #'petrucci
      \override Staff.TimeSignature.style = #'mensural
      \clef "petrucci-c4"
      \[ a1 g f e \]
      \[ a1 g\longa \]
      \[ \tweak left-down-stem ##t a\breve b
         \tweak right-down-stem ##t g\longa \]
      \[ \tweak right-down-stem ##t b\maxima
         \tweak right-up-stem ##t g\longa \]
    }
    \layout {
      \context {
        \Voice
        \remove Ligature_bracket_engraver
        \consists Mensural_ligature_engraver
      }
    }
  }
  

  

• The use of the file gregorian.ly is deprecated. While still distributed for backward compatibility, it should be replaced with a VaticanaScore context together with some manual \layout changes (if necessary): code like

  \include "gregorian.ly"
  
  \score {
    \new VaticanaStaff { ... }
  }
  

  should become

  \new VaticanaScore {
    \new VaticanaStaff { ... }
  }
  
  \layout {
    indent = 0
    ragged-last = ##t
  }
  

• LilyPond’s ‘arabic’ note name language is deprecated. While still working for backward compatibility (if you load hel-arabic.ly), it is recommended to use ‘english’, ‘italiano’, or your preferred note name language instead.
• Defaults for fret labels in fret diagrams have changed.
  • − The default value for fret-label-vertical-offset is set to -0.5, which centers the label in the fret space.
  • − The default number format is now 'custom, with a format string of "~dfr" (resulting in ‘3fr’, for example), instead of 'roman-lower.
• Two new options are available for fret-diagram-details:
  • − string-overhang allows to define the extension of string lines beyond the last fret line, in multiples of fret-distance. Default value 1.
  • − barre-thickness defines the thickness of the barre line, in multiples of dot-radius. Only defined for barre-type=straight. Default value 1.
• The command \autoBeamOff now stops auto-beaming immediately. Previously, its effect was delayed if a beam generated by the auto-beamer engraver was still active.
• It is no longer necessary to switch off auto-beaming while using \crossStaff.
• The \upbow and \downbow signs are now properly inverted if used below a staff. As a consequence, the glyphs scripts.upbow and scripts.downbow have been renamed to scripts.uupbow and scripts.udownbow, respectively, and the new inverted glyphs are named scripts.dupbow and scripts.ddownbow.

  \relative c' {
    f4^\downbow f^\upbow f_\downbow f_\upbow
  }
  

  

• In lyrics aligned to a melody, extender lines can now be added automatically for words ending in a melisma.

  \relative {
    d'4 e f4 g8( f
    e4 d c2)
  }
  \addlyrics {
    \set autoExtenders = ##t
    A me -- lis -- ma.
  }
  

  

• By default, chord names are now always shown with English pitch names, no longer dependent on \language. Similarly, commands like \germanChords are no longer dependent on \language either.

  This change might cause differences in displayed chord names.

• A new command \englishChords is now available, making it possible to switch back to English chord names.
• Some Scheme functions related to chord names have been renamed.

  old	new
  note-name->string	pitch->name
  alteration->text-accidental-markup	accidental->text-markup
  note-name->markup	chord-name:markup
  chord-name->german-markup	chord-name:german-markup
  note-name->german-markup	chord-name:german-lowercase-name-markup
  chord-name->italian-markup	chord-name:italian-markup

  convert-ly handles this automatically.

• Two new Scheme functions related to chord names are now available: pitch->alteration returns the accidental for a given pitch and language; chord-name:name-markup returns note name markup for a given pitch and language.
• LilyPond now follows the Ignatzek chord name scheme more closely. This reverts changes introduced in version 2.15.21 (in 2011), which are now considered as incorrect and/or ambiguous.

  oldException = { <c e g b fis'>-\markup \super "lyd" }
  chExceptions = #(append (sequential-music-to-chord-exceptions
                           oldException #t)
                          ignatzekExceptions)
  
  music = { <c e g d'>1 | <c es g f'> | <c e g b fis'> }
  
  \new StaffGroup \with { instrumentName = "old:" }
  <<
    \new ChordNames \with {
      chordNameExceptions = #chExceptions
      additionalPitchPrefix = ""
    } \music
    \new Voice \transpose c c' \music
  >>
  
  \new StaffGroup \with { instrumentName = "new:" }
  <<
    \new ChordNames \music
    \new Voice \transpose c c' \music
  >>
  
  \layout {
    indent = 1\cm
    line-width = 9\cm
    ragged-right = ##f
  }