Info Catalog lilypond-learning: The overrideProperty command lilypond-learning: Tweaking methods

lilypond-learning: The tweak command

 
 The ‘\tweak’ command
 ....................
 
 The final tweaking command which is available is ‘\tweak’.  This should
 be used when several objects occur at the same musical moment, but you
 only want to change the properties of selected ones, such as a single
 note within a chord.  Using ‘\override’ would affect all the notes
 within a chord, whereas ‘\tweak’ affects just the following item in the
 input stream.
 
    Here’s an example.  Suppose we wish to change the size of the middle
 note head (the E) in a C major chord.  Let’s first see what ‘\once
 \override’ would do:
 
      <c e g>4
      \once \override NoteHead.font-size = #-3
      <c e g>4
      <c e g>4
      [image src="" alt="[image of music]" text="image of music"]
 
    We see the override affects _all_ the note heads in the chord.  This
 is because all the notes of a chord occur at the same _musical moment_,
 and the action of ‘\once’ is to apply the override to all layout objects
 of the type specified which occur at the same musical moment as the
 ‘\override’ command itself.
 
    The ‘\tweak’ command operates in a different way.  It acts on the
 immediately following item in the input stream.  In its simplest form,
 it is effective only on objects which are created directly from the
 following item, essentially note heads and articulations.
 
    So to return to our example, the size of the middle note of a chord
 would be changed in this way:
 
      <c e g>4
      <c \tweak font-size #-3 e g>4
      [image src="" alt="[image of music]" text="image of music"]
 
    Note that the syntax of ‘\tweak’ is different from that of the
 ‘\override’ command.  The context should not be specified; in fact, it
 would generate an error to do so.  Both context and layout object are
 implied by the following item in the input stream.  Note also that an
 equals sign should not be present.  So the simple form of the ‘\tweak’
 command is
 
      \tweak LAYOUT-PROPERTY #VALUE
 
    A ‘\tweak’ command can also be used to modify just one in a series of
 articulations, as shown here:
 
      a4^"Black"
        -\tweak color #red ^"Red"
        -\tweak color #green _"Green"
      [image src="" alt="[image of music]" text="image of music"]
 
 Note that the ‘\tweak’ command must be preceded by an articulation mark
 since the tweaked expression needs to be applied as an articulation
 itself.  In case of multiple direction overrides (‘^’ or ‘_’), the
 leftmost override wins since it is applied last.
 
    Objects such as stems and accidentals are created later, and not
 directly from the following event.  It is still possible to use ‘\tweak’
 on such indirectly created objects by explicitly naming the layout
 object, provided that LilyPond can trace its origin back to the original
 event:
 
      <\tweak Accidental.color #red   cis4
       \tweak Accidental.color #green es
       g>
      [image src="" alt="[image of music]" text="image of music"]
 
    This long form of the ‘\tweak’ command can be described as
 
      \tweak LAYOUT-OBJECT.LAYOUT-PROPERTY VALUE
 
    The ‘\tweak’ command must also be used to change the appearance of
 one of a set of nested tuplets which begin at the same musical moment.
 In the following example, the long tuplet bracket and the first of the
 three short brackets begin at the same musical moment, so any
 ‘\override’ command would apply to both of them.  In the example,
 ‘\tweak’ is used to distinguish between them.  The first ‘\tweak’
 command specifies that the long tuplet bracket is to be placed above the
 notes and the second one specifies that the tuplet number is to be
 printed in red on the first short tuplet bracket.
 
      \tweak direction #up
      \tuplet 3/4 {
        \tweak color #red
        \tuplet 3/2 { c8[ c c] }
        \tuplet 3/2 { c8[ c c] }
        \tuplet 3/2 { c8[ c c] }
      }
      [image src="" alt="[image of music]" text="image of music"]
 
    If nested tuplets do not begin at the same moment, their appearance
 may be modified in the usual way with ‘\override’ commands:
 
      \tuplet 3/2 { c8[ c c] }
      \once \override TupletNumber.text = #tuplet-number::calc-fraction-text
      \tuplet 3/2 {
        c8[ c]
        c8[ c]
        \once \override TupletNumber.transparent = ##t
        \tuplet 3/2 { c8[ c c] }
        \tuplet 3/2 { c8[ c c] }
      }
      [image src="" alt="[image of music]" text="image of music"]
 
 
 See also
 ........
 
    Notation Reference: (lilypond-notation)The tweak command.
 

Info Catalog lilypond-learning: The overrideProperty command lilypond-learning: Tweaking methods