Re: Hairpin endings

[Nathan Ho]

On 2017-04-20 20:42, Andrew Bernard wrote:
> I posted a while ago with a query about hairpins, to which no
> response.
>
> Would there be any way to have hairpins that don't start, or end in
> the other direction, with the lines converging to the same point? I
> have need from time to time of hairpins where the end points are still
> separated, rather than coming to a termination together. Sure this can
> be done with a whiteout box, but that is always fiddly and the
> position tends to move when the score is repaginated etc etc. In the
> same way as the 'height' property allows you to specify the separation
> at the open end, it would be useful to have some property for this
> sort of thing at the pointy end. Yes, definitely not Common Era
> engraving practice, but this keeps coming up in the New Complexity
> scores I work with.

hi andrew,

check it out:

#(define ((open-hairpin left-open right-open) grob)
   (let* ((stencil (ly:hairpin::print grob))
          (X-ext (ly:stencil-extent stencil X))
          (Y-ext (ly:stencil-extent stencil Y))
          (width (interval-length X-ext))
          (height (interval-length Y-ext)))
     (ly:stencil-translate
       (grob-interpret-markup grob
         (markup
           (#:path 0.1
             (list (list 'moveto 0 (* height (- 0.5 (* 0.5 left-open))))
                   (list 'lineto width (* height (- 0.5 (* 0.5 
right-open))))
                   (list 'moveto 0 (* height (+ 0.5 (* 0.5 left-open))))
                   (list 'lineto width (* height (+ 0.5 (* 0.5 
right-open))))))))
       (cons 0 (interval-start Y-ext)))))

{
  c'1\> c'1 c'1\!
  \once \override Hairpin.stencil = #(open-hairpin 1.0 0.5)
  c'1\> c'1 c'1\!
  \once \override Hairpin.stencil = #(open-hairpin 0.5 0.0)
  c'1\> c'1 c'1\!
}

respects height, but not thickness. anyone know how to convert a 
thickness value into staff spaces?


nathan