Re: Augmentation dot positioning

[Chris Yate]

On 15 Sep 2016 22:45, "Carl Sorensen" <address@hidden> wrote:
>
>
> On 9/15/16 10:41 AM, "Chris Yate" <address@hidden> wrote:>
> >
> >I think the trouble with Gould's rules is that they're inconsistent, or
> >could at least be interpreted in such a way.  She says to use dots only
> >on the spaces occupied by the chord, and yet says you MAY need to put a
> >dot a space or more away from the chord.
>
> No, let me summarize Gould's rules.
>
> Rule 1: Every notehead in a chord must take a duration dot.
>
> Rule 2: Move dots away from a note head on a line by moving it either up
> or down (she has some guidelines for how to do this, but I'm skipping them
> right now)
>
> Rule 3: Every dot needs to have a staff space to itself.  This implies
> (although it's not explicitly stated, but it is shown) that you may need
> to move dots farther than one staff space away from the note head.
>
> Rule 4: Center the dots on the chord.  This fixes problems that may show
> up by applying rule 3.
>
> Rule 5: If one of the remaining dots is two or more staff spaces from the
> chord, the dot pattern is bad, so instead of having one dot per note head,
> just have one dot per staff space included in the chord.
>
> Every example she shows is consistent with these rules.  The examples you
> show from Sibelius are not consistent with these rules.  That doesn't make
> them wrong, just inconsistent with Gould.
>
>
> >
> >
> >
> >At the very least, we should be able to decide in our own scores what
> >logic is used for dot placement :-)
>
> Yes.  Perhaps we could make a scheme callback for cleaning up dots.  And
> that could become a property of a DotColumn, and the user would be free to
> implement their own Scheme function for cleaning up the dots.
>
> >
> >
> >Are you editing the code in dot-column.cc. or is there some Scheme code
> >for this too?
>
> Just editing code in dot-column.cc.  No Scheme code anywhere that I can
> see.
>
> So what rules do you use to decide when a dot is necessary below the
> bottom note of a chord, above the top of a chord, or in the middle of a
> chord with an interval larger than a third?
>
> Looking at your statements in Dots.ly, I would infer the following rules:
>
>
> 1. Put dots next to note heads on staff spaces.
> 2. Put dots in the space above note heads on staff lines.  If the space is
> already taken, and the space below the note head is available, place the
> dot in the space below the note head.  If the space is already taken, and
> the space below the note head is taken as well, omit the dot.
>
>
> I think those two rules provide the dots that you have considered to be
> necessary in Dots.ly, without any of the dots you consider unnecessary.

Please note I'm working without her examples,  but I disagree about [Lilypond's interpretation of] Gould's rules, because they appear to be in contradiction with **every piece of published music I've ever seen**.

Given just her text, I think she has possibly not worded things as clearly as possible. And if it is correct to have five dots on a chord spanning a ninth == five spaces, then why is it incorrect to have three dots for a chord spanning three spaces?

The place that her rules stop making sense is this inconsistency:

1. It's ok to have a dot a full two staff positions away from the top or bottom of the chord.

2. BUT... if there's a dot that according to the rules turns up to be two spaces away, don't place ANY notes outside the range of spaces occupied by the chord *.

* spaces occupied by the chord includes the half space occupied by part of a notehead on a line.

I think what she actually meant, and basing this also on guides like the ABRSM theory books, is

- every note needs a dot, where possible
- notes on a line need their dot moving up or down to the nearest space
- sometimes the dot needs to shift away from its parent, and that's ok within the compass of the chord
- dots two or more staff _positions_ (not staff _spaces_ as written) away from the top or bottom of the chord look strange, so exclude those.

Pragmatically though, I strongly believe it's a mistake for Lilypond's defaults to go against the grain of what most readers of music expect and have learnt to expect, even if the holy grail appears to say it's "right".

Thanks, Chris