Re: Stems push things away

[Thomas Morley]

Am Sa., 23. Jan. 2021 um 02:59 Uhr schrieb Brian Bartling
<brian.bartling23@gmail.com>:
>
> Thank you, Jean. That does fix this example. I still suspect the root cause 
> of my problem lies in how the lengths and positions of stems that are 
> attached to beams are calculated. I'm guessing that your idea of removing the 
> Stem_engraver and the Note_spacing_engraver is somehow connected to this 
> comment inside Note_spacing::get_spacing:
>
>       /*
>         Ugh. If Stem is switched off, we don't know what the
>         first note head will be.
>       */
>
> The only problem is, there are still spots where I detect this problem where 
> things outside-staff are being pushed away, even when I remove the 
> Stem_engraver and the Beam_engraver. After experimenting a bit more, I found 
> that I was able to fix my problem completely with these two commands:
>
>    \override Beam.quantized-positions = #'(0 . 0)   (I noticed this actually 
> takes an interval instead of a boolean)
>    \override Stem.length = #0
>
> The default definition of Stem.length is ly:stem::calc-length, and this 
> function throws an error if you change the definition of 
> Beam.quantized-positions. Again, though, it's surprising that all of these 
> functions are still running even though I shut off stems and beams. I'm not 
> really sure why.
>
> Thanks again!
> Brian
>
> On Fri, Jan 22, 2021 at 12:38 PM Jean Abou Samra <jean@abou-samra.fr> wrote:
>>
>> > Hello,
>> >
>> > Sometimes stems push things that are outside-staff further outside,
>> > even with things like TabStaff, which removes the Stem stencil. Take
>> > this, for example:
>> >
>> > \version "2.23.0"
>> >
>> > \new TabStaff \with {
>> >   \revert Stem.stencil
>> >   \revert TextScript.stencil
>> >
>> >   \consists "Timing_translator"
>> > % \override Beam.quantized-positions = ##f
>> > }{
>> >     \time 2/4
>> >     << { a,8^A a'^B } \\ { c''4 r4 } >>
>> > }
>> >
>> > The B is significantly higher than the A, because the calculated stem
>> > sticks outside the staff. This happens even when the stem stencil
>> > isn't reverted, but I reverted it to show what I think is going on. It
>> > happens without the Timing_translator as well, though it's less
>> > pronounced.
>> >
>> > I would like to completely shut off the internal stem calculation in
>> > order to get the A and the B on the same level, but I can't figure out
>> > how. I was able to shut off the calculation for stem lengths by
>> > setting Beam.quantized-positions to false, but this results in
>> > lilypond errors.
>> >
>> > Thanks for the help!
>> > Brian Bartling
>>
>> Hi,
>>
>> Maybe something like this? Don't ask me why it works, I have no idea!
>>
>> \version "2.23.0"
>>
>> \layout {
>>    \context {
>>      \TabVoice
>>      \remove "Stem_engraver"
>>      \remove "Note_spacing_engraver"
>>    }
>>    \context {
>>      \TabStaff
>>      \revert TextScript.stencil
>>    }
>> }
>>
>> \new TabStaff {
>>    \time 2/4
>>    << { a,8^AAAA a'^B } \\ { c''4 r4 } >>
>> }
>>
>> Best,
>> Jean
>>

Hi Brian,

why do you do
  \consists "Timing_translator"

Without it

\new TabStaff \with {
  \revert TextScript.stencil
}{
    \time 2/4
    << { a,8^A a'^B } \\ { c''4 r4 } >>
}

works as expected.

Cheers,
  Harm