Re: Issue 3330: redo much of the stencil stacking/spacing/empty-check (issue 8869044)

[k-ohara5a5a]

I worry a little about making the extent of markup different from the
union of its components.  Someone may have used  c4^\markup{\hspace #-3
"text"}  and the left side of the "text" is now vulnerable to
collisions.

The alternative is to use a variable to remember the cursor position in
a loop that assembles a line of markup.

In patch-set "yet another typo" the extent of the markup
assembled-so-far is used to record that cursor position, but in \markup
{"_pple" \hspace#-6.5 "A"} the you really don't want the markup extent
to end the cursor position, after the "A", because the "pple" extends
farther right.

On 2013/04/28 22:38:16, dak wrote:
> On 2013/04/28 22:16:14, Keith wrote:

https://codereview.appspot.com/8869044/diff/9001/scm/define-markup-commands.scm#newcode3765
> > scm/define-markup-commands.scm:3765: * \\translate #'(2 . 3)
translate
> > Probably this example should place the translated markup relative to
music,
> > rather than in a line of \markup; otherwise, someone might
experiment with
> > this and conclude that \translate cannot move things to the left.

> Well, the example works, and I'd like to avoid meddling with it right
now

The example might not work after your patch.
\translate #(x . y) moves the stencil relative to its reference point,
but the extents go with the stencil.  If you space a line of markup
based on extents (not reference points) then these examples with
\translate #(x . y) in a line of markup will show no visible effect of
the x.


https://codereview.appspot.com/8869044/diff/27001/lily/stencil.cc
File lily/stencil.cc (right):

https://codereview.appspot.com/8869044/diff/27001/lily/stencil.cc#newcode257
lily/stencil.cc:257: bool separate = !is_empty (other_axis (a)) &&
!s.is_empty (other_axis (a));
suggest  separate =>  !special_spacing

https://codereview.appspot.com/8869044/diff/27001/lily/stencil.cc#newcode266
lily/stencil.cc:266: // determined by their respective stencils to allow
for spacing
This is where the magic happens, so good to have some search-words in
the comment.

// If either stencil has special spacing, such as \hspace#3,
// use the individual stencil extents for the corresponding
// limit of the resulting extent, to allow \hspace#-3 to backspace

https://codereview.appspot.com/8869044/diff/27001/scm/define-markup-commands.scm
File scm/define-markup-commands.scm (right):

https://codereview.appspot.com/8869044/diff/27001/scm/define-markup-commands.scm#newcode3765
scm/define-markup-commands.scm:3765: * \\translate #'(2 . 3) translate
might fail

https://codereview.appspot.com/8869044/diff/27001/scm/define-markup-commands.scm#newcode3767
scm/define-markup-commands.scm:3767: * \\translate-scaled #'(2 . 3)
translate-scaled
might fail

https://codereview.appspot.com/8869044/diff/27001/scm/define-markup-commands.scm#newcode3898
scm/define-markup-commands.scm:3898: Translate @var{arg} relative to its
surroundings.  @var{offset}
might become "... relative to its alignment point."

https://codereview.appspot.com/8869044/diff/27001/scm/define-markup-commands.scm#newcode3904
scm/define-markup-commands.scm:3904: \\translate #'(2 . 3)
might fail

https://codereview.appspot.com/8869044/diff/27001/scm/markup.scm
File scm/markup.scm (right):

https://codereview.appspot.com/8869044/diff/27001/scm/markup.scm#newcode69
scm/markup.scm:69: @var{space} before them and don't avoid overlapping
other stencils."
The last sentence of this comment should go with its implementation in
stencil.cc

https://codereview.appspot.com/8869044/