Line arrows
Arrows can be applied to text-spanners and line-spanners (such as the
Glissando).
\relative c'' {
\override TextSpanner.bound-padding = #1.0
\override TextSpanner.style = #'line
\override TextSpanner.bound-details.right.arrow = ##t
\override TextSpanner.bound-details.left.text = #"fof"
\override TextSpanner.bound-details.right.text = #"gag"
\override TextSpanner.bound-details.right.padding = #0.6
\override TextSpanner.bound-details.right.stencil-align-dir-y = #CENTER
\override TextSpanner.bound-details.left.stencil-align-dir-y = #CENTER
\override Glissando.bound-details.right.arrow = ##t
\override Glissando.arrow-length = #0.5
\override Glissando.arrow-width = #0.25
a8\startTextSpan gis a4 b\glissando b,
g'4 c\stopTextSpan c2
}