Re: Gets rid of length in the docs. (issue 4965053)

[Dmytro O. Redchuk]

On Tue 30 Aug 2011, 16:08 Mike Solomon wrote:
> Currently, the stem stencil function is doable in Scheme, which means that
> the result from 2.15.8 can be achieved via :
Thank you for your work! I've "bookmarked" this hint/thread, of course.

I am still wondering, is stem the single grob so far, which 'Y-extent property
"overrides" its appearance? Or other grobs will be (or already are) changed,
too?

Sorry for dumb questions, if any. Thank you for bearing with me.)


> #(define (my-stem grob)
>   (let*
>     ((dir (ly:grob-property grob 'direction))
>      (half-space (* 0.5 (ly:staff-symbol-staff-space grob)))
>      (y1 (* half-space (ly:stem::calc-stem-begin-position grob)))
>      (y2 (* half-space (ly:stem::calc-stem-end-position grob)))
>      (half-thick (* (* (ly:grob-property grob 'thickness)
>                        (ly:staff-symbol-line-thickness grob))
>                     0.5))
>      (beam (ly:grob-object grob 'beam))
>      (y2 (+ y2 (if (null? beam)
>                    0.0
>                    (* dir (* (ly:grob-property beam
>                                                'beam-thickness)
>                              half-space)))))
>      (my-down (if (< y2 y1) y2 y1))
>      (my-up (if (< y2 y1) y1 y2))
>      (blot (ly:paper-get-number (ly:grob-layout grob) 'blot-diameter)))
>    (ly:make-stencil `(round-filled-box ,half-thick
>                                        ,half-thick
>                                        ,(- my-down)
>                                        ,my-up
>                                        ,blot)
>                     (cons (- half-thick) half-thick)
>                     (cons my-down my-up))))
> 
> {
>  c''_\fermata
>  \override Stem #'Y-extent = #'(-10 . 0)
>  \override Stem #'stencil = #my-stem
>  c''_\fermata
> }
> 
> I'm not sure of a good way to deal with this from a UI perspective, but at
> least the function above allows you to achieve the result you're talking
> about with only one extra override

-- 
  Dmytro O. Redchuk                        "Easy to use" is easy to say.
  Bug Squad                                             -- Jeff Garbers