Wow - that looks really useful - it'll take me about 3 days to digest all
that info - but thank you so much for helping me.
I had read the Scheme tutorial but still struggled .
This is great - I love it that there is so much to learn.
Kind regards
Colin
On Sun, 16 Oct 2022 at 21:33, Jean Abou Samra <j...@abou-samra.fr> wrote:
> Le 16/10/2022 à 16:43, Colin Baguley a écrit :
> > Hi there,
> > By reading this mailing list I've recently discovered how to add some
> > text in a box to my music which doesn't
> > affect any other elements of the score. This is an example of what I
> mean.
> >
> > \mark \markup {\with-dimensions-from \null
> > \translate #'(1.0 . -4.0)
> > \override #'(font-name . "Calibra Bold ")
> > \fontsize #3
> > \with-color #(x11-color "Red")
> > \box \whiteout "Some text here" }
> >
> > So, my next challenge was to make this into a function so that I
> > could alter the font, size, colour,
> > position etc on the fly so to speak but I'm struggling with Scheme
> > syntax here.
> > I've managed to work out position and fontsize, but struggling with
> > the rest. Here is how far I've
> > got. Could someone improve on this please [ and also comment on why
> > the 'whiteout' isn't perfect ]
>
>
>
> Like this?
>
> \version "2.22.2"
>
> specialbox =
> #(define-music-function (coord marktext fsize fname color) (pair?
> markup? number? string? color?)
> #{
> \once \override Score.RehearsalMark.layer = 5
> \mark \markup {\with-dimensions-from \null
> \translate #coord
> \override #`(font-name . ,fname)
> \fontsize #fsize
> \with-color #color
> \box \whiteout $marktext }
> #})
> %---------------------------------------------------
> melody = \relative c' {
> \repeat unfold 4 { c8 d e f g f e d } \break
>
> \specialbox #'(0.0 . -4.0 ) #"Testing 123" #3 "Linux Libertine"
> #(x11-color "red")
>
> \repeat unfold 4 { c8 d e f g f e d } \break
> }
> %----------------------------------------------------
> \score {
> \new Staff { \melody }
> \layout { }
> }
> %----------------------------------------------------
>
>
>
>
>
> For the color, there is nothing special, just replace #(x11-color "red"),
> a Scheme expression that always evaluates to the same color, with #color,
> a Scheme expression that evaluates to the 'color' parameter of the
> function. The predicate for colors that you need to put in the signature
> is color? . For font-name, you need to use Scheme quasiquoting syntax,
> with a backtick ` instead of a quote ' . This allows you to use a comma
> to evaluate an expression inside the quoted expression. Quoting and
> quasiquoting can be confusing for Scheme beginners. Perhaps this will
> help a bit, although the part about quasiquoting is admittedly short:
>
> https://tutoriel-scheme.readthedocs.io/en/latest/quoting.html#quasiquotes
>
> You can also search the net for 'Scheme quasiquoting' and find plenty
> of explanations of this concept.
>
> If you don't like (quasi)quoting, you can always use the more verbose
>
> #(cons 'font-name fname)
>
> instead of
>
> #`(font-name . ,fname)
>
> By the way, I don't understand why you use $marktext. The difference
> between # and $ is subtle but in most cases you don't need to know
> about it and you can just use #.
>
> Now, you know how to do this, but actually it is not necessary, and you
> will likely start to find writing all parameters every time inconvenient.
> All the markup transformations you are doing except \box are also available
> in the form of properties, so you can just as well do
>
> \version "2.22.2"
>
> melody = \relative c' {
> \override Score.RehearsalMark.whiteout = ##t
> \override Score.RehearsalMark.X-extent = ##f
> \override Score.RehearsalMark.Y-extent = ##f
> \override Score.RehearsalMark.vertical-skylines = ##f
> \override Score.RehearsalMark.horizontal-skylines = ##f
> \override Score.RehearsalMark.outside-staff-priority = ##f
> \override Score.RehearsalMark.font-size = 3
> %% Change to a font available on your computer
> \override Score.RehearsalMark.font-name = "Linux Libertine"
> \override Score.RehearsalMark.color = #(x11-color "red")
> %% These two lines work around spurious failures that have been fixed
> %% in LilyPond 2.23.x. They occur in LilyPond 2.22 if X-offset and
> %% Y-offset are not overridden/tweaked.
> \override Score.RehearsalMark.X-offset = 0
> \override Score.RehearsalMark.Y-offset = 0
>
> \repeat unfold 4 { c8 d e f g f e d } \break
>
> \tweak X-offset 2 \tweak Y-offset -8 \mark \markup \box "Testing 123"
>
> \repeat unfold 4 { c8 d e f g f e d } \break
> }
> %----------------------------------------------------
> \score {
> \new Staff { \melody }
> \layout { }
> }
> %----------------------------------------------------
>
>
>
> As you can see, you can use overrides and/or tweaks to change the
> properties,
> so when you don't want any change from the default values, you don't have
> to write out the defaults every time.
>
> About the whiteout issue: LilyPond draws each object on a certain layer.
> Most objects are on layer 1. The order in which objects from the same
> layer are drawn is not specified. So you need to move the RehearsalMark
> a few layers up so that it is drawn on top of other objects, by adding
>
> \override Score.RehearsalMark.layer = 5
>
>
> A final note: are you aware of this LSR snippet?
>
> https://lsr.di.unimi.it/LSR/Item?id=1000
>
> Best,
> Jean
>
>
