beam.color(optional)Color of beams, including those associated with tuplets.
Value conforms to data.COLOR.
beam.rend(optional)Encodes whether a beam is "feathered" and in which direction.
Allowed values are:
"acc" (Beam lines grow farther apart from left to right.), "rit" (Beam lines grow closer together from left to right.), "norm" (Beam lines are equally-spaced over the entire length of the beam.)
beam.slope(optional)Captures beam slope.
Value is a decimal number.