Re: Determine if a stem is present

[Thomas Morley]

2017-03-27 11:38 GMT+02:00 Urs Liska <address@hidden>:
> Hi all,
>
> I want to know if a given notehead has a stem attached. Obviously even
> whole notes do have a stem object, but with zero extent.
>
> I've found the following calculation to be reliable, but I can't imagine
> it has to be so complicated:
>
>     (if (or (= +inf.0 (car stem-y-extent))
>             (= -inf.0 (car stem-y-extent))
>             (= +inf.0 (cdr stem-y-extent))
>             (= -inf.0 (cdr stem-y-extent)))
>
> (with stem-y-extent being the Y-extent property of the stem object).
>
> I think there should be some property I can ask directly about this? But
> I didn't find any suspicious entry for Stem or stem-interface.
>
> Any suggestions?
> Urs

interval-sane?

exp.:

(interval-sane? (ly:stencil-extent empty-stencil X))
--> #f

Maybe grob::is-live? may help as well, didn't test that.


HTH,
  Harm