Re: Pedal gradual release

[Aaron Hill]

On 2019-01-20 3:04 am, Andrew Bernard wrote:
> I use a wedge type symbol to indicate gradual release of a piano
> pedal. Since this is not built in to lilypond, I developed code like
> the following to do the job, using PostScript. I don't mind using
> PostScript as I am fluent in it, but objectively, this is terribly
> special case code. Is there anybody willing to generalise this and
> make it more user friendly for other people who don't necessarily want
> to fiddle with PostScript and Reverse Polish Notation when we are just
> trying to write piano music.
>
> [ . . . ]

One option would be to exploit a Hairpin:

%%%%
sustainGradualRelease =
  -\tweak shorten-pair #'(0 . 1.35)
  -\tweak height #1
  -\tweak style #'dashed-line
  -\tweak self-alignment-Y #DOWN
  -\tweak to-barline ##f
  -\tweak stencil #(elbowed-hairpin '((0 . 0) (1 . 1)) #f)
  \<

sustainPedal = {
  s4\sustainOn s s\sustainGradualRelease s s s\!\sustainOff
}
%%%%

This is far from ideal, as a hairpin by default will attempt to align to 
the right extent of the musical column (unless the column has a rest, 
and then it aligns to the left).  The piano bracket aligns to the left, 
so setting shorten-pair is needed to have the hairpin meet the piano 
bracket.

You would need to adjust the edge-height of the piano bracket if you 
want the triangular section to be taller.

-- Aaron Hill