circle around stem

[Orm Finnendahl]

Hi,

 trying to define an overwrite to draw a circle around a stem I came
up with the code below. Unfortunately it doesn't automagically work
for all use cases as can be seen in the attached image: The code
doesn't take the number of flags into account. I know that the stem
length can be altered with a tweak, but I'd prefer this to be
corrected without manual intervention. Is there a way within the
damp-stem function to force a minimum stem-length depending on the
number of flags if notes aren't beamed?

--
Orm

8<-----------------------------------------------------------------------
#(define (damp-stem grob)
   (if (ly:stencil? (ly:stem::print grob))
    (let* ((stencil (ly:stem::print grob))
           (X-ext (ly:stencil-extent stencil X))
           (Y-ext (ly:stencil-extent stencil Y))
           (dir (ly:grob-property grob 'direction))
           (width (interval-length X-ext))
           (len (interval-length Y-ext))
           (y-offs (if (= dir 1) 1.29 (- len 1.29))))
     (ly:stencil-translate
      (grob-interpret-markup grob
       (markup
        (#:path width
         (list (list 'moveto -0 0)
          (list 'lineto -0 len)))
        (#:hspace -1.13)
        (#:circle
         (#:path 0.15
          (list 
           (list 'moveto 0 y-offs))))))
      (cons 0 (interval-start Y-ext))))
    #f))

damp = { \once  \override Stem.stencil = #damp-stem }

{\autoBeamOff
 \override Stem.stencil = #damp-stem c'4 c'8 c'16 c'32 c'64 s32 c''4 c''8 c''16 
c''32 c''64 }
8<-----------------------------------------------------------------------

damp.png
Description: PNG image