Re: Tweaking notehead direction in chords

[Paul Morris]

On Dec 20, 2012, at 7:51 PM, Thomas Morley <address@hidden> wrote:

> We should provide a shorter example than my last.
> I used the custom-note-heads only for advanced testings.
> I'd prefer a double-line, though, above the original, below the tweaked 
> version.

Sounds good to me.  I can work on that.


> (2) LilyPond
> So far so good and LilyPond _does_ it quite good.
> Though, the amount of covering the stem-width isn't the same for left
> and right printed noteheads.
> For up-stems a left-printed notehead covers the whole stem-width but a
> right-printed one only about the half (or two-thirds?).
> Not sure about the reasoning.

Looking at your example with the colored note heads, it seems like (1) note 
heads on the default side of the stem will overlap the whole stem width, and 
(2) any notes on the opposite, non-default side will overlap about half of the 
stem width.  So:

  Upwards stem
    Notes on the left (default): overlap full stem width
    Notes on the right: overlap about half the stem width

  Downwards stem
    Notes on the right (default): overlap full stem width 
    Notes on the left: overlap about half the stem width

It seems that we could achieve the same result for manually shifted note heads. 
 We could just adjust how far to shift them based on whether the note was being 
moved in the default direction or non-default direction (left or right) for the 
given stem direction (up or down).  Is that right?


> I think there is no way to align moved noteheads left and right from
> the stem _and_ to keep a correct 'stem-attachment in x-axis-direction
> in all thinkable cases.

If what I wrote above is correct, then it seems that we could achieve both of 
these, at least in most cases, as a default.  But maybe I'm missing something 
about why we can't have both, at least not in all cases?  Sorry if you are 
already a few steps ahead of me here.

I don't have time at the moment to try to put any of this into code, but maybe 
it's better to see what you think first anyway?


> (3) Solution
> Apart from correcting the above mentioned wrong expression, I changed
> \adjustStem.
> It now requiers a pair as argument.
> The car of it adds multiples of the stem-width to the x-default.
> The cdr multiplies with the y-default (as before).

This seems like a good change in any case, allowing for more flexibility.


> Would be very nice if you could have a look again. :)

Sure thing.

Thanks again,
-Paul