On Tue, Oct 5, 2010 at 11:09 AM, Mark Polesky
<address@hidden> wrote:
WRT the flexible vertical spacing dimensions, the upper
attachment points for 'space and 'minimum-distance currently
align with the Y-coordinate of the origin (0,0) of the upper
item. For systems this is the middle line of the nearest
staff, and for markups this is the highest point of the
markup. In the newest docs (NR 4.1.2 as of yesterday),
these are called "reference points".
I think that most of the resulting dimensions are what the
user would naturally expect them to be, except when the
upper item is a title/markup. In these cases, I think the
most natural attachment point would be the *bottom* of the
upper markup.
I would argue that the baseline is more natural then the bottom. Moreover, using the baseline as a reference point will result in more even spacing of multiple consecutive lines of markup.
This applies to 3 of the 8 flexible vertical dimensions:
* after-title-spacing
* between-title-spacing
* bottom-system-spacing
The proposed change to after-title-spacing needs no comment.
For between-title-spacing however, I should mention that if
the upper attachment point (of 'space and 'minimum-distance)
is moved to the bottom of the upper markup, then the
'padding value is basically rendered redundant.
This is not actually true (even if we change the refpoint to the bottom) because minimum-distance measures the distance from the refpoint of the markup to the *refpoint* of the next system, while padding measures the distance to the *top* of the next system.
In that
case, 'padding would only influence the spacing if it were
larger than 'minimum-distance, and making 'padding larger
than 'minimum-distance is generally pointless since that in
turn would render 'minimum-distance redundant. That being
said, I don't think this is a problem; the spacing behavior
would still be more natural IMO. And a simple explanation
for this unique case could be added to the docs.
Of the three, bottom-system-spacing is slightly more
complicated, since it currently controls the spacing below
systems *and* markups, when either is the last on a page.
So the natural attachment point for systems would remain the
same, but would be shifted to the lowest Y-coordinate for
markups (ideally).
Personally, I think we should add a new variable to control
the spacing between a markup and the bottom margin. We
could call it bottom-markup-spacing for now, but see this
post for my proposed variable renaming:
This is easy enough to add (and the naming seems fine to me).
Cheers,
Joe