Would there be another way to do that? (which would span to the right note, and accept "dal niente" circle, for example?)
%%code
\relative c' {
\once \override Hairpin #'stencil = #ly:text-interface::print
\once \override Hairpin #'text = \markup{
\path #0.1
#'((moveto 0 0)
(lineto 6 0.25)
(rcurveto 0 0 0.2 0 0.25 0.3)
(moveto 0 0)
(lineto 6 -0.25)
(rcurveto 0 0 0.2 0 0.25 -0.3)
)}
c2.\< ~
c8 d8 e4\!
}
%%end
PS: I remember that Mike Solomon was working with experimental eps/ps spanners... is this in any case integrated into LilyPond?