Notes, Chords, and Rests

Through the Chordrest class, neoscore can automatically draw notes, chords, and rests given pitches and a duration. This will automatically create and lay out noteheads, stems, flags, rhythm dots, accidentals, ledger lines, and rest glyphs as requested, with decent room for customization.

staff = Staff(ORIGIN, None, Mm(100))
Clef(ZERO, staff, 'treble')
Chordrest(staff.unit(2), staff, ["c", "g", "eb'"], (3, 16))

Chordrests are shaped by two main arguments - a list of pitches and a duration.

Pitches

Pitches can be specified using a string shorthand similar to that used by Lilypond. The string shorthand consists of three parts: a pitch letter, an accidental, and octaves marks.

• Pitch letters are the standard c through b letters.

• The accidental may be f or b for flat, s or # for sharp, n for natural, ss or x for double-sharp, and ff or bb for double-flat.

• The octave indication is given by a series of apostrophes (') or commas (,), where each apostrophe increases the pitch by an octave, and each comma decreases it. All octave transformations are relative to the octave starting at middle-C. The absence of an octave indicator means a pitch is within the octave starting at middle-C. (Note that this differs from Lilypond’s notation, which starts at the octave below middle-C.)

Some examples:

• Middle-C: c

• The B directly below that: b,

• The C one octave below middle-C: c,

• The E-flat above middle-C: ef or eb

• The F-sharp above middle-C: fs or f#

• The G-double-sharp above middle-C: fx or fss

• The A-double-flat above the treble staff: aff' or abb'

Note

Key signatures are purely cosmetic, so pitches in chordrests should always be given the written accidentals desired.

Note

There is a known bug with accidental layout in tight chords. See Issue #32 for a workaround.

Durations

Durations are specified with 2-tuples resembling fractions of a whole note. The lower number should be power of 2, while the upper number can be any value so long as it can be represented in a single note without ties.

staff = Staff(ORIGIN, None, Mm(100))
Clef(ZERO, staff, 'bass')
Chordrest(Mm(0), staff, ["c"], (1, 4))
Chordrest(Mm(10), staff, ["c"], (1, 8))
Chordrest(Mm(20), staff, ["c"], (3, 8))
Chordrest(Mm(30), staff, ["c"], (1, 1))
Chordrest(Mm(40), staff, ["c"], (2, 1))
Chordrest(Mm(50), staff, ["c"], (3, 128))

It can be a bit difficult to work out the numerical representations of durations with many dots, so you can also use Duration.from_description to specify durations in terms of their base divisions and dot counts:

# Triple-dotted 16th note
>>> Duration.from_description(16, 3)
Duration(fraction=Fraction(15, 128), ...)
# Double-dotted whole note
>>> Duration.from_description(1, 2)
Duration(fraction=Fraction(7, 4), ...)
# Dotted double-breve (double-breve uses 0 as its base division)
>>> Duration.from_description(0, 1)
Duration(fraction=Fraction(3, 1), ...)

Note

Because durations are given as written, they have no concept of tuplets. Durations in tuplets should be specified in their written forms, then tuplet annotations can then be placed over the relevant note group.

Rests

Rests are just chordrests without any notes.

staff = Staff(ORIGIN, None, Mm(100))
Clef(ZERO, staff, 'treble')
Chordrest(Mm(0), staff, None, (1, 4))
Chordrest(Mm(10), staff, None, (1, 8))
Chordrest(Mm(20), staff, None, (3, 8))

By default rests are placed in the middle of the staff, but you can override their vertical position if needed.

staff = Staff(ORIGIN, None, Mm(100))
Clef(ZERO, staff, 'treble')
Chordrest(Mm(0), staff, None, (1, 4), rest_y=staff.unit(-2))