}
@end lilypond
-Now the bar lines have vanished.
+Now the bar lines have vanished. Setting the @code{stencil}
+property to @code{#f} is such a frequent operation that there is a
+shorthand for it called @code{\omit}:
+@funindex \omit
+
+@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
+{
+ \time 12/16
+ \omit Staff.BarLine
+ c4 b8 c d16 c d8 |
+ g,8 a16 b8 c d4 e16 |
+ e8
+}
+@end lilypond
Note, though, that setting the @code{stencil} property to @code{#f}
will cause errors when the dimensions of the object are required for
These control respectively whether bar lines are printed at the end of
a line, in the middle of lines, and at the beginning of lines. For
our example we want all bar lines to be suppressed, so the value we
-need is @code{'#(#f #f #f)}. Let's try that, remembering to include
+need is @code{#(#f #f #f)} (also available
+under the name @code{all-invisible}). Let's try that, remembering to include
the @code{Staff} context. Note also that in writing this value we
-have @code{#'#} before the opening bracket. The @code{'#} is required
-as part of the value to introduce a vector, and the first@tie{}@code{#} is
+have @code{##} before the opening parenthesis. One @code{#} is required
+as part of vector constant syntax, and the first@tie{}@code{#} is
required, as always, to precede the value itself in the
@code{\override} command.
@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
{
\time 12/16
- \override Staff.BarLine.break-visibility = #'#(#f #f #f)
+ \override Staff.BarLine.break-visibility = ##(#f #f #f)
c4 b8 c d16 c d8 |
g,8 a16 b8 c d4 e16 |
e8
@end lilypond
@noindent
-The time signature is gone, but this command leaves a gap where
+Again, setting the @code{transparent} property is a rather
+frequent operation, so we have a shorthand for it called
+@code{\hide}:
+@funindex \hide
+
+@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
+{
+ \time 12/16
+ \hide Staff.TimeSignature
+ c4 b8 c d16 c d8 |
+ g,8 a16 b8 c d4 e16 |
+ e8
+}
+@end lilypond
+
+@noindent
+In either case, the time signature is gone, but this command
+leaves a gap where
the time signature should be. Maybe this is what is wanted for
an exercise for the student to fill it in, but in other
circumstances a gap might be undesirable. To remove it, the
@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
{
\time 12/16
- \override Staff.TimeSignature.stencil = ##f
+ \omit Staff.TimeSignature
c4 b8 c d16 c d8 |
g,8 a16 b8 c d4 e16 |
e8
@noindent
and the difference is obvious: setting the stencil to @code{#f}
+(possibly via @code{\omit})
removes the object entirely; making the object @code{transparent}
+(which can be done using @code{\hide})
leaves it where it is, but makes it invisible.
@subheading color
@noindent
and again, we see the bar lines are not visible. Note that
@emph{white} is not preceded by an apostrophe -- it is not
-a symbol, but a @emph{function}. When called, it provides
+a symbol, but a @emph{variable}. When evaluated, it provides
the list of internal values required to set the color to
-white. The other colors in the normal list are functions
+white. The other colors in the normal list are variables
too. To convince yourself this is working you might like
-to change the color to one of the other functions in the
+to change the color to one of the other variables in the
list.
@cindex color, X11
The second way of changing the color is to use the list of
X11 color names in the second list in @ruser{List of colors}.
-However, these must be preceded by another function, which
-converts X11 color names into the list of internal values,
-@code{x11-color}, like this:
+However, these are mapped to the actual values by the function
+@code{x11-color} which
+converts X11 color symbols into the list of internal values like this:
@cindex BarLine, example of overriding
@cindex color property, example
@noindent
Note that in this case the function @code{x11-color} takes
a symbol as an argument, so the symbol must be preceded by
-an apostrophe and the two enclosed in brackets.
+an apostrophe to keep it from being evaluated as a variable, and
+the whole function call has to be enclosed in parentheses.
@cindex rgb colors
@cindex color, rgb
@funindex rgb-color
-There is yet a third function, one which converts RGB values into
+There is another function, one which converts RGB values into
internal colors -- the @code{rgb-color} function. This takes
three arguments giving the intensities of the red, green and
blue colors. These take values in the range 0 to 1. So to
@cindex alignAboveContext property, example
@cindex @code{\with}, example
-@cindex stencil property, example
+@funindex \omit
@cindex Clef, example of overriding
@cindex TimeSignature, example of overriding
alignAboveContext = #"main"
}
{
- \override Staff.Clef.stencil = ##f
- \override Staff.TimeSignature.stencil = ##f
+ \omit Staff.Clef
+ \omit Staff.TimeSignature
{ f8 f c }
}
>>
But what is the difference between modifying the staff context by
using @code{\with} and modifying the stencils of the clef and the
-time signature with \override? The main difference is that
+time signature with @code{\override}, or in this case
+@code{\omit}?
+The main difference is that
changes made in a @code{\with} clause are made at the time the
context is created, and remain in force as the @strong{default}
values for the duration of that context, whereas
}
@end lilypond
+It turns out that we can also employ the shorthands @code{\hide}
+and @code{\omit} for setting the @code{transparent} property and
+clearing the @code{stencil} here, leading to the result
+
+@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
+\new Staff ="main" {
+ \relative g' {
+ r4 g8 g c4 c8 d |
+ e4 r8
+ <<
+ { f8 c c }
+ \new Staff \with {
+ alignAboveContext = #"main"
+ % Don't print clefs in this staff
+ \omit Clef
+ % Don't print time signatures in this staff
+ \omit TimeSignature
+ }
+ { f8 f c }
+ >>
+ r4 |
+ }
+}
+@end lilypond
+
Finally we come to changing the size of layout objects.
Some layout objects are created as glyphs selected from a typeface
{ f8 c c }
\new Staff \with {
alignAboveContext = #"main"
- \override Clef.stencil = ##f
- \override TimeSignature.stencil = ##f
+ \omit Clef
+ \omit TimeSignature
% Reduce all font sizes by ~24%
fontSize = #-2
}
{ f8 c c }
\new Staff \with {
alignAboveContext = #"main"
- \override Clef.stencil = ##f
- \override TimeSignature.stencil = ##f
+ \omit Clef
+ \omit TimeSignature
fontSize = #-2
% Reduce stem length and line spacing to match
\override StaffSymbol.staff-space = #(magstep -2)
@tab Tuplets are below/above notes
@end multitable
-Note that these predefined commands may @strong{not} be
+The neutral/normal variants of these commands are implemented
+using @code{\revert} and may @strong{not} be
preceded by @code{\once}. If you wish to limit the
-effect to a single note you must either use the equivalent
-@code{\once \override} command or use the predefined command
-followed after the affected note by the corresponding
-@code{\xxxNeutral} command.
+effect of the other commands (which are implemented using
+@code{\override}) to a single timestep, you can precede them with
+@code{\once} like you would do with explicit overrides.
@unnumberedsubsubsec Fingering
>>
@end lilypond
+@funindex \single
+@cindex tweak, generated from override
+Now for @emph{overriding} the transparency of a graphical object,
+we could have used the shorthand @code{\hide} as explained above.
+Tweaking is a different operation, affecting only properties
+generated from a single music expression. It turns out that we
+can convert overrides into tweaks using @code{\single}, making it
+possible to rewrite the above example as
+
+@lilypond[quote,fragment,relative=2,verbatim]
+<<
+ {
+ \single \hide Stem
+ \single \hide Flag
+ \tweak Stem.length #8
+ b8~ b\noBeam
+ }
+\\
+ { b8[ g] }
+>>
+@end lilypond
+
+In this particular case, the difference to @code{\once \hide} is
+not apparent. It is important when there are several objects at
+the same point in musical time (like noteheads in a chord). In
+that case, @code{\once} will affect all of those objects while
+@code{\single} will only affect a single one, the one generated by
+the immediately following music expression.
+
@subheading Simulating a fermata in MIDI
@cindex stencil property, use of
% Visible tempo marking
\tempo 4=120
a4 a a
- \once \override Score.MetronomeMark.transparent = ##t
+ \once \hide Score.MetronomeMark
% Invisible tempo marking to lengthen fermata in MIDI
\tempo 4=80
a4\fermata |
% Visible tempo marking
\tempo 4=120
a4 a a
- \once \override Score.MetronomeMark.stencil = ##f
+ \once \omit Score.MetronomeMark
% Invisible tempo marking to lengthen fermata in MIDI
\tempo 4=80
a4\fermata |
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