Has piano pedal brackets end on the right of a note column.

Has piano pedal brackets end on the right of a note column.

[Keith, 2011-08-19 03:01:03]

A swing and a miss, I'm afraid.

See input/regression/pedal-bracket for what the original alignment goals were. 
(You could expand that reg-test to cover issue 723)

I think the correct fix is merely to ignore suspended heads, which could be
implemented as aligning to the stem for down-stems.  I find good evidence to
back that up I'll post on the bug tracker.

[mikesol_ufl.edu, 2011-08-19 06:33:35]

On Aug 19, 2011, at 5:01 AM, k-ohara5a5a@oco.net wrote:

> A swing and a miss, I'm afraid.
> 
> See input/regression/pedal-bracket for what the original alignment goals
> were.  (You could expand that reg-test to cover issue 723)
> 
> I think the correct fix is merely to ignore suspended heads, which could
> be implemented as aligning to the stem for down-stems.  I find good
> evidence to back that up I'll post on the bug tracker.
> 

If this is the fix, my recent work on 620 could be tweaked a bit to be used in
this situation as well.  Currently, bound-interfaces is a property that resides
in the grobs being aligned to (note columns, paper columns).  If instead bound
interfaces resides in the grobs that are being aligned (hairpins, line spanners,
piano pedals), then the same note column could be aligned to different ways for
different grobs.  The more I think about it, the more it makes sense.  Let me
know if you think this'd be a good option.

Cheers,
MS

[Keith, 2011-08-19 07:51:27]

On Thu, 18 Aug 2011 23:25:40 -0700, Mike Solomon <mikesol@ufl.edu> wrote:

> On Aug 19, 2011, at 5:01 AM, k-ohara5a5a@oco.net wrote:
>> I think the correct fix is merely to ignore suspended heads, which could
>> be implemented as aligning to the stem for down-stems.  I find good
>> evidence to back that up I'll post on the bug tracker.
>>
>
> If this is the fix,

I don't know until next time I look at Ted Ross' book in the library.  I have
lots of piano music, but pedaling is very rarely written explicitly.

I would have thought piano pedal brackets would work just like hairpins, but
input/regression/pedal-bracket.ly says they end a bit earlier, at the /left/ of
the main note column.

> my recent work on 620 could be tweaked a bit to be used in this situation as
well.  Currently, bound-interfaces is a property that resides in the grobs being
aligned to (note columns, paper columns).  If instead bound interfaces resides
in the grobs that are being aligned (hairpins, line spanners, piano pedals),
then the same note column could be aligned to different ways for different
grobs.  The more I think about it, the more it makes sense.  Let me know if you
think this'd be a good option.
>

You mean your new 'bound-alignment-interfaces.  I didn't follow issue 620, but
looking now I don't see how it helps.  We would want to find the left extent of
the note-heads in the main note column, excluding suspended note-heads. 
(Actually, I think that is the x-reference point for the NoteColumn)

[mikesol_ufl.edu, 2011-08-19 08:14:33]

On Aug 19, 2011, at 9:51 AM, Keith OHara wrote:

> 
> You mean your new 'bound-alignment-interfaces.  I didn't follow issue 620, but
looking now I don't see how it helps.  We would want to find the left extent of
the note-heads in the main note column, excluding suspended note-heads. 
(Actually, I think that is the x-reference point for the NoteColumn)
> 
> 

Imagine that bound interfaces were not a list but rather a lazy alist of
interfaces and callbacks.  For example:

`((clef-interface . ,my-clef-interface-callback) (key-signature-interface .
,(ly:simple-closure ,my-key-signature-callback-that-needs-an-extra-argument 1))
bar-line-interface)

Lazy alist because it can also contain non-pairs, in which case a default extent
callback along a given axis is used as the callback.

The axis group interface recurses through this list, applying the callback to
grobs that contain interfaces in the alist to get the extent of that grob
according to the callback.

So, now, say that you want to align to a note column a particular way for
piano-pedal-brackets.  The bound-alignment-interfaces alist would look like:

`((note-column-interface .
,my-note-column-callback-specific-to-piano-pedal-brackets))

And my-note-column-callback would be something to the effect of:

#(define (my-note-column-callback-specific-to-piano-pedal-brackets grob)
exclude-all-left-noteheads-from-extent)

This seems swiss-army-knife tweakable: it generalizes the problem of finding
different extents for the same grob depending on the grob that needs to be
aligned by rolling all extent-finding callbacks into an alist (not unlike the
concept of grob properties in the first place).

Cheers,
MS

[mail_philholmes.net, 2011-08-19 08:34:02]

----- Original Message ----- 
From: "Keith OHara" <k-ohara5a5a@oco.net>
To: <mtsolo@gmail.com>; <lilypond-devel@gnu.org>; 
<reply@codereview.appspotmail.com>; "Mike Solomon" <mikesol@ufl.edu>
Sent: Friday, August 19, 2011 8:51 AM
Subject: Re: Has piano pedal brackets end on the right of a note 
column.(issue 4899050)


> On Thu, 18 Aug 2011 23:25:40 -0700, Mike Solomon <mikesol@ufl.edu> wrote:
>
>> On Aug 19, 2011, at 5:01 AM, k-ohara5a5a@oco.net wrote:
>>> I think the correct fix is merely to ignore suspended heads, which could
>>> be implemented as aligning to the stem for down-stems.  I find good
>>> evidence to back that up I'll post on the bug tracker.
>>>
>>
>> If this is the fix,
>
> I don't know until next time I look at Ted Ross' book in the library.  I 
> have lots of piano music, but pedaling is very rarely written explicitly.


I've got a PDF of Ross - could let you have a copy of the bit on pedals, if 
you want.  Not sure it's explicit enough, but you're welcome.Elaine Gould 
has 6 pages on pedalling, which could be scanned if required.

--
Phil Holmes