3.2.12 beam-interface

A beam.

The thickness property is the weight of beams, measured in staffspace. The direction property is not user-serviceable. Use the direction property of Stem instead.

User settable properties:

annotation (string)

Annotate a grob for debug purposes.

auto-knee-gap (dimension, in staff space)

If a gap is found between note heads where a horizontal beam fits that is larger than this number, make a kneed beam.

beamed-stem-shorten (list)

How much to shorten beamed stems, when their direction is forced. It is a list, since the value is different depending on the number of flags and beams.

beaming (pair)

Pair of number lists. Each number list specifies which beams to make. 0 is the central beam, 1 is the next beam toward the note, etc. This information is used to determine how to connect the beaming patterns from stem to stem inside a beam.

break-overshoot (pair of numbers)

How much does a broken spanner stick out of its bounds?

clip-edges (boolean)

Allow outward pointing beamlets at the edges of beams?

concaveness (number)

A beam is concave if its inner stems are closer to the beam than the two outside stems. This number is a measure of the closeness of the inner stems. It is used for damping the slope of the beam.

damping (number)

Amount of beam slope damping.

direction (direction)

If side-axis is 0 (or #X), then this property determines whether the object is placed #LEFT, #CENTER or #RIGHT with respect to the other object. Otherwise, it determines whether the object is placed #UP, #CENTER or #DOWN. Numerical values may also be used: #UP=1, #DOWN=-1, #LEFT=-1, #RIGHT=1, #CENTER=0.

gap (dimension, in staff space)

Size of a gap in a variable symbol.

gap-count (integer)

Number of gapped beams for tremolo.

grow-direction (direction)

Crescendo or decrescendo?

inspect-quants (pair of numbers)

If debugging is set, set beam and slur quants to this position, and print the respective scores.

knee (boolean)

Is this beam kneed?

length-fraction (number)

Multiplier for lengths. Used for determining ledger lines and stem lengths.

neutral-direction (direction)

Which direction to take in the center of the staff.

positions (pair of numbers)

Pair of staff coordinates (left . right), where both left and right are in staff-space units of the current staff. For slurs, this value selects which slur candidate to use; if extreme positions are requested, the closest one is taken.

thickness (number)

Line thickness, generally measured in line-thickness.

Internal properties:

details (list)

Alist of parameters for detailed grob behavior.

More information on the allowed parameters can be found by inspecting ‘lily/slur-scoring.cc’, ‘lily/beam-quanting.cc’, and ‘lily/tie-formatting-problem.cc’. Setting debug-tie-scoring, debug-beam-scoring or debug-slur-scoring also provides useful clues.

least-squares-dy (number)

The ideal beam slope, without damping.

normal-stems (unknown)

An array of visible stems.

quant-score (string)

The beam quanting score; stored for debugging.

quantized-positions (pair of numbers)

The beam positions after quanting.

shorten (dimension, in staff space)

The amount of space that a stem is shortened. Internally used to distribute beam shortening over stems.

stems (unknown)

A list of stem objects, corresponding to the notes that the arpeggio has to be before.

This grob interface is used in the following graphical object(s): Beam.

Internals Reference