Aligning bar numbers
Bar numbers by default are right-aligned to their parent object. This
is usually the left edge of a line or, if numbers are printed within a
line, the left hand side of a bar line. The numbers may also be
positioned directly over the bar line or left-aligned to the bar line.
\relative c' {
\set Score.currentBarNumber = 111
\override Score.BarNumber.break-visibility = #all-visible
% Increase the size of the bar number by 2
\override Score.BarNumber.font-size = 2
% Print a bar number every second measure
\set Score.barNumberVisibility = #(every-nth-bar-number-visible 2)
c1 | c1
% Center-align bar numbers
\override Score.BarNumber.self-alignment-X = #CENTER
c1 | c1
% Left-align bar numbers
\override Score.BarNumber.self-alignment-X = #LEFT
c1 | c1
}