Re: add stencil-whiteout-outline function (issue 236480043 by address@hidden)

[paulwmorris]

Thanks for the reviews.

On 2015/05/24 22:56:44, Keith wrote:
> I think whiteout-stencil should simply call this function, with the
defaults
> suggested, so that the existing
> \set Xx.whiteout=##t and \markup\whiteout use this new method.

> We could provide access to the old whiteout method with
> \set Xx.block-whiteout and \markup\block-whiteout
> for the former extent-based whiteout.

Sounds good to me.  In that case... would it make sense to name this new
function "stencil-whiteout" so that it replaces the current function,
and then the current function could be renamed "stencil-box-whiteout" or
similar?  Then we would have:

\set Xx.box-whiteout \markup \box-whiteout

I like "box" rather than "block" since "block" can more easily be
misread as a verb and "box" is shorter.




https://codereview.appspot.com/236480043/diff/1/scm/stencil.scm
File scm/stencil.scm (right):

https://codereview.appspot.com/236480043/diff/1/scm/stencil.scm#newcode700
scm/stencil.scm:700: (angle-increments 12) (radial-increments 3))
On 2015/05/24 22:56:43, Keith wrote:
> I am so far happy testing (angle-increments 16) (radial-increments 1)
with 16
> copies instead of 36.

I tried this out, and found it to work well, even on glyphs with thin
lines like treble clef and time signatures.

https://codereview.appspot.com/236480043/diff/1/scm/stencil.scm#newcode749
scm/stencil.scm:749: (ly:stencil-extent stil Y))))))
On 2015/05/24 22:56:43, Keith wrote:
> The whiteout-stencil still affects the position of objects outside the
staff,
> because LilyPond uses the outlines stencils (not extents) for several
spacing
> tasks.

> There are other situations (\page-ref and \with-dimensions) where we
need one
> stencil for spacing, and another for final printing, so we delay the
formation
> of the final-printing stencil.   That method seems appropriate here as
well:

>           (let ((whiteout-expr
>                  (ly:stencil-expr
>                   (stencil-with-color
>                    (radial-plot offset stil empty-stencil)
>                    color))))
>            (ly:stencil-add
>              (ly:make-stencil
>                `(delay-stencil-evaluation ,(delay whiteout-expr)))
>              stil)))))

Thanks.  I was not aware of this, but glad there's an easy fix.

https://codereview.appspot.com/236480043/diff/1/scm/stencil.scm#newcode749
scm/stencil.scm:749: (ly:stencil-extent stil Y))))))
On 2015/05/25 22:24:01, Keith wrote:
> When I tried making stencil-whitéout' call the new improved function,
I had
> trouble with
>    \override Staff.Clef.whiteout = ##t
>    \override Staff.Clef.color = #red
> the whiteout was also red because the code in grob.cc applies the
color before
> handing the stencil to stencil-whiteout-outline, and in composed
stencils with
> color applied at different levels, the innermost 'color applies.

> I added code to remove any 'color at top-level so I can continue using
this.
> Ideally we would want code to remove any 'color from the stencil
before using it
> as whiteout, but it might be more appropriate to apply 'whiteout
before 'color
> in grob.cc.

I am not that comfortable working in the C++ side of things, so if we go
that route (and that sounds like the better approach) I won't be much
help.

https://codereview.appspot.com/236480043/