-@c -*-texinfo-*-
+@c -*- coding: utf-8; mode: texinfo; -*-
+@c This file is part of lilypond.tely
+@ignore
+ Translation of GIT committish: FILL-IN-HEAD-COMMITTISH
+
+ When revising a translation, copy the HEAD committish of the
+ version that you are working on. See TRANSLATION for details.
+@end ignore
+
@node Changing defaults
@chapter Changing defaults
The purpose of LilyPond's design is to provide the finest output
-quality as a default. Nevertheless, it may happen that you need to
+quality as a default. Nevertheless, it may happen that you need to
change this default layout. The layout is controlled through a large
-number of proverbial ``knobs and switches.'' This chapter does not
-list each and every knob. Rather, it outlines what groups of controls
+number of proverbial @q{knobs and switches.} This chapter does not
+list each and every knob. Rather, it outlines what groups of controls
are available and explains how to lookup which knob to use for a
-certain effect.
+particular effect.
+
+
+@cindex Internals Reference
The controls available for tuning are described in a separate
-document, the @internalsref{Program reference} manual. That manual
+document, the
+@iftex
+Internals Reference manual.
+@end iftex
+@ifnottex
+@ref{Top,Internals Reference,,lilypond-internals}.
+@end ifnottex
+That manual
lists all different variables, functions and options available in
-LilyPond. It is written as a HTML document, which is available
-@uref{http://lilypond.org/doc/Documentation/user/out-www/lilypond-internals/,on-line},
+LilyPond. It is written as a HTML document, which is available
+@c leave the @uref as one long line.
+@uref{http://@/lilypond@/.org/@/doc/@/stable/@/Documentation/@/user/@/lilypond@/-internals/,on@/-line},
but is also included with the LilyPond documentation package.
-There are three areas where the default settings may be changed:
-
-@itemize @bullet
-@item Output: changing the appearance of individual
- objects. For example, changing stem directions, or the location of
- subscripts.
-
-@item Context: changing aspects of the translation from music events to
- notation. For example, giving each staff a separate time signature.
-
-@item Global layout: changing the appearance of the spacing, line
- breaks and page dimensions.
-@end itemize
+There are four areas where the default settings may be changed:
+
+@itemize
+@item
+Automatic notation: changing the automatic creation of notation
+elements. For example, changing the beaming rules.
+
+@item
+Output: changing the appearance of individual
+objects. For example, changing stem directions or the location of
+subscripts.
-Then, there are separate systems for typesetting text (like
-@emph{ritardando}) and selecting different fonts. This chapter also
-discusses these.
+@item
+Context: changing aspects of the translation from music events to
+notation. For example, giving each staff a separate time signature.
+
+@item
+Page layout: changing the appearance of the spacing, line
+breaks, and page dimensions. These modifications are discussed
+in @ref{Non-musical notation}, and @ref{Spacing issues}.
+@end itemize
Internally, LilyPond uses Scheme (a LISP dialect) to provide
infrastructure. Overriding layout decisions in effect accesses the
-program internals, so it is necessary to learn a (very small) subset
-of Scheme. That is why this chapter starts with a short tutorial on
-entering numbers, lists, strings and symbols in Scheme.
+program internals, which requires Scheme input. Scheme elements are
+introduced in a @code{.ly} file with the hash mark
+@code{#}.@footnote{@rlearning{Scheme tutorial}, contains a short tutorial
+on entering numbers, lists, strings, and symbols in Scheme.}
@menu
-* Scheme tutorial::
-* File structure::
* Interpretation contexts::
-* Tuning output::
-* Fonts::
-* Text markup::
-* Global layout::
+* The \override command::
@end menu
-@node Scheme tutorial
-@section Scheme tutorial
-
-@cindex Scheme
-@cindex GUILE
-@cindex Scheme, in-line code
-@cindex accessing Scheme
-@cindex evaluating Scheme
-@cindex LISP
-
-LilyPond uses the Scheme programming language, both as part of the
-input syntax, and as internal mechanism to glue together modules of
-the program. This section is a very brief overview of entering data in
-Scheme.@footnote{If you want to know more about Scheme, see
-@uref{http://www.schemers.org}.}
-
-The most basic thing of a language is data: numbers, character
-strings, lists, etc. Here is a list of data types that are relevant to
-LilyPond input.
-
-@table @asis
-@item Booleans
- Boolean values are True or False. The Scheme for True is @code{#t}
- and False is @code{#f}.
-@item Numbers
- Numbers are entered in the standard fashion,
- @code{1} is the (integer) number one, while @code{-1.5} is a
- floating point number (a non-integer number).
-@item Strings
- Strings are enclosed in double quotes,
- @example
- "this is a string"
- @end example
-
- Strings may span several lines
- @example
- "this
- is
- a string"
- @end example
-
- Quotation marks and newlines can also be added with so-called escape
- sequences. The string @code{a said "b"} is entered as
- @example
- "a said \"b\""
- @end example
-
- Newlines and backslashes are escaped with @code{\n} and @code{\\}
-respectively.
-@end table
-
-
-In a music file, snippets of Scheme code are introduced with the hash
-mark @code{#}. So, the previous examples translated in LilyPond are
-
-@example
- ##t ##f
- #1 #-1.5
- #"this is a string"
- #"this
- is
- a string"
-@end example
-
-For the rest of this section, we will assume that the data is entered
-in a music file, so we add @code{#}s everywhere.
-
-Scheme can be used to do calculations. It uses @emph{prefix}
-syntax. Adding 1 and 2 is written as @code{(+ 1 2)} rather than the
-traditional 1+2.
-
-@lisp
- #(+ 1 2)
- @result{} #3
-@end lisp
-
-The arrow @result{} shows that the result of evaluating @code{(+ 1 2)}
-is @code{3}. Calculations may be nested; the result of a function may
-be used for another calculation.
-
-@lisp
- #(+ 1 (* 3 4))
- @result{} #(+ 1 12)
- @result{} #13
-@end lisp
-
-These calculations are examples of evaluations; an expression like
-@code{(* 3 4)} is replaced by its value @code{12}. A similar thing
-happens with variables. After defining a variable
-
-@example
- twelve = #12
-@end example
-
-variables can also be used in expressions, here
-
-@example
- twentyFour = #(* 2 twelve)
-@end example
-
-the number 24 is stored in the variable @code{twentyFour}.
-
-The @emph{name} of a variable is also an expression, similar to a
-number or a string. It is entered as
-
-@example
- #'twentyFour
-@end example
-
-The quote mark @code{'} prevents Scheme interpreter from substituting
-@code{24} for the @code{twentyFour}. Instead, we get the name
-@code{twentyFour}.
-
-This syntax will be used very frequently, since many of the layout
-tweaks involve assigning (Scheme) values to internal variables, for
-example
-
-@example
- \override Stem #'thickness = #2.6
-@end example
-
-This instruction adjusts the appearance of stems. The value @code{2.6}
-is put into a the @code{thickness} variable of a @code{Stem}
-object. This makes stems almost twice as thick as their normal size.
-To distinguish between variables defined in input files (like
-@code{twentyFour} in the example above), and internal variables, we
-will call the latter ``properties.'' So, the stem object has a
-@code{thickness} property.
-
-Two-dimensional offsets (X and Y coordinates) as well as object sizes
-(intervals with a left and right point) are entered as @code{pairs}. A
-pair@footnote{In Scheme terminology, the pair is called @code{cons},
-and its two elements are called car and cdr respectively.} is entered
-as @code{(first . second)} and, like symbols, they must be quoted,
-
-@example
- \override TextScript #'extra-offset = #'(1 . 2)
-@end example
-
-This assigns the pair (1, 2) to @code{extra-offset} variable of the
-TextScript object. This moves the object 1 staff space to the right,
-and 2 spaces up.
-
-The two elements of a pair may be arbitrary values, for example
-
-@example
- #'(1 . 2)
- #'(#t . #f)
- #'("blah-blah" . 3.14159265)
-@end example
-
-A list is entered by enclosing its elements in parentheses, and adding
-a quote. For example,
-@example
- #'(1 2 3)
- #'(1 2 "string" #f)
-@end example
-
-We have been using lists all along. A calculation, like @code{(+ 1
-2)} is also a list (containing the symbol @code{+} and the numbers 1
-and 2). Normally lists are interpreted as calculations, and the Scheme
-interpreter substitutes the outcome of the calculation. To enter a
-list, we stop evaluation. This is done by quoting the list with a
-quote @code{'} symbol. For calculations, do not use a quote.
-
-Inside a quoted list or pair, there is no need to quote anymore. The
-following is a pair of symbols, a list of symbols and a list of lists
-respectively,
-
-@example
- #'(stem . head)
- #'(staff clef key-signature)
- #'((1) (2))
-@end example
-
-@node File structure
-@section File structure
-
-The following items may be present in a @file{.ly} file at toplevel
-
-@itemize @bullet
-@item An output definition, such as @code{\bookpaper}, @code{\midi}
-and @code{\paper}. Such a definition at toplevel changes the default
-settings for the block entered.
-
-@item An @code{\header} block. This sets the global header block. This
-is the block containing the definitions for book-wide settings, like
-composer, title, etc.
-
-@item An @code{\addquote} statement. See @ref{Quoting other voices}
-for more information.
-
-@item A @code{\score} block. This score will be collected with other
-toplevel scores, and combined as a single @code{\book}.
-
-This behavior can be changed by setting the variable
-@code{toplevel-score-handler} at toplevel. The default handler is
-defined in the init file @file{scm/lily.scm}.
-
-@item A @code{\book} block formats the block
-
-This behavior can be changed by setting the variable
-@code{toplevel-book-handler} at toplevel. The default handler is
-defined in the init file @file{scm/lily.scm}.
-
-
-@item A compound music expression, such as
-@example
- @{ c'4 d' e'2 @}
-@end example
-
-This will add the piece in a @code{\score}, and formats it into a
-single book together with all other toplevel @code{\score}s and music
-expressions.
-
-This behavior can be changed by setting the variable
-@code{toplevel-music-handler} at toplevel. The default handler is
-defined in the init file @file{scm/lily.scm}.
-
-@end itemize
-
-The following example shows three things which may be entered at
-toplevel
-@verbatim
- \paper {
- % movements are non-justified by default
- raggedright = ##t
- }
-
- \header {
- title = "Do-re-mi"
- }
-
- { c'4 d' e2 }
-@end verbatim
+@node Interpretation contexts
+@section Interpretation contexts
-At any point in a file, any of the following lexical instructions can
-be entered:
+This section describes what contexts are, and how to modify them.
-@itemize @bullet
-@item @code{\version}
-@item @code{\include}
-@item @code{\encoding}
-@item @code{\renameinput}
-@end itemize
+@menu
+* Contexts explained::
+* Creating contexts::
+* Changing context properties on the fly::
+* Modifying context plug-ins::
+* Layout tunings within contexts::
+* Changing context default settings::
+* Defining new contexts::
+* Aligning contexts::
+* Vertical grouping of grobs::
+@end menu
-
-@node Interpretation contexts
-@section Interpretation contexts
+@node Contexts explained
+@subsection Contexts explained
-When music is printed, a lot of notation elements must be added to the
-input, which is often bare bones. For example, compare the input and
-output of the following example:
+When music is printed, a lot of notational elements must be added to the
+output. For example, compare the input and output of the following example:
-@lilypond[verbatim,relative=2,fragment]
- cis4 cis2. g4
+@lilypond[quote,verbatim,relative=2,fragment]
+cis4 cis2. g4
@end lilypond
The input is rather sparse, but in the output, bar lines, accidentals,
-clef, and time signature are added. LilyPond @emph{interprets} the
-input. During this step, the musical information is inspected in time
-order, similar to reading a score from left to right. While reading,
-the program remembers where measure boundaries are, and what pitches
-need explicit accidentals. This information can be presented on
+clef, and time signature are added. LilyPond @emph{interprets} the
+input. During this step, the musical information is inspected in time
+order, similar to reading a score from left to right. While reading
+the input, the program remembers where measure boundaries are, and which
+pitches require explicit accidentals. This information can be presented on
several levels. For example, the effect of an accidental is limited
-to a single stave, while a bar line must be synchronized across the
+to a single staff, while a bar line must be synchronized across the
entire score.
Within LilyPond, these rules and bits of information are grouped in
-so-called Contexts. Examples of context are @context{Voice},
-@context{Staff}, and @context{Score}. They are hierarchical, for
-example, a @context{Staff} can contain many @context{Voice}s, and a
-@context{Score} can contain many @context{Staff} contexts.
+@emph{Contexts}. Some examples of contexts are @code{Voice},
+@code{Staff}, and @code{Score}. They are hierarchical, for
+example: a @code{Staff} can contain many @code{Voice}s, and a
+@code{Score} can contain many @code{Staff} contexts.
+
+@quotation
+@sourceimage{context-example,5cm,,}
+@end quotation
Each context has the responsibility for enforcing some notation rules,
creating some notation objects and maintaining the associated
-properties. So, the synchronization of bar lines is handled at
-@context{Score} context. The @context{Voice} may introduce an
-accidentals and then the @context{Staff} context maintains the rule to
-show or suppress the accidental for the remainder of the measure.
-
-For simple scores, contexts are created implicitly, and you need not
-be aware of them. For larger pieces, such as piano music, they must be
+properties. For example, the @code{Voice} context may introduce an
+accidental and then the @code{Staff} context maintains the rule to
+show or suppress the accidental for the remainder of the measure. The
+synchronization of bar lines is handled at @code{Score} context.
+
+However, in some music we may not want the bar lines to be
+synchronized -- consider a polymetric score in 4/4 and 3/4 time. In
+such cases, we must modify the default settings of the @code{Score}
+and @code{Staff} contexts.
+
+For very simple scores, contexts are created implicitly, and you need
+not be aware of them. For larger pieces, such as anything with more
+than one staff, they must be
created explicitly to make sure that you get as many staves as you
need, and that they are in the correct order. For typesetting pieces
with specialized notation, it can be useful to modify existing or
-define new contexts.
+to define new contexts.
-Full description of all available contexts is in the program
+A complete description of all available contexts is in the program
reference, see
@ifhtml
@internalsref{Contexts}.
@end ifhtml
-@ifnothtml
-Translation @arrow{} Context.
+@ifnothtml
+Translation @expansion{} Context.
@end ifnothtml
@c [TODO: describe propagation]
-@menu
-* Creating contexts::
-* Changing context properties on the fly::
-* Modifying context plug-ins::
-* Layout tunings within contexts::
-* Changing context default settings::
-* Defining new contexts::
-* Which properties to change::
-@end menu
-
@node Creating contexts
@subsection Creating contexts
-For scores with only one voice and one staff, correct contexts are
-created automatically. For more complex scores, it is necessary to
-create them by hand. There are three commands which do this.
+For scores with only one voice and one staff, contexts are
+created automatically. For more complex scores, it is necessary to
+create them by hand. There are three commands that do this.
+
+@itemize
+@item
The easiest command is @code{\new}, and it also the quickest to type.
It is prepended to a music expression, for example
-@cindex @code{\new}
+@funindex \new
@cindex new contexts
@cindex Context, creating
@example
- \new @var{type} @var{music expression}
+\new @var{type} @var{music expression}
@end example
@noindent
where @var{type} is a context name (like @code{Staff} or
@code{Voice}). This command creates a new context, and starts
-interpreting @var{music expression} with that.
+interpreting the @var{music expression} with that.
A practical application of @code{\new} is a score with many
-staves. Each part that should be on its own staff, is preceded with
+staves. Each part that should be on its own staff, is preceded with
@code{\new Staff}.
-@lilypond[verbatim,relative=2,raggedright,fragment]
- << \new Staff { c4 c }
- \new Staff { d4 d }
- >>
+@lilypond[quote,verbatim,relative=2,ragged-right,fragment]
+<<
+ \new Staff { c4 c }
+ \new Staff { d4 d }
+>>
@end lilypond
-@cindex @code{\context}
+The @code{\new} command may also give a name to the context,
+
+@example
+\new @var{type} = @var{id} @var{music}
+@end example
+However, this user specified name is only used if there is no other
+context already earlier with the same name.
+
+@funindex \context
+
+@item
Like @code{\new}, the @code{\context} command also directs a music
-expression to a context object, but gives the context an extra name. The
+expression to a context object, but gives the context an explicit name. The
syntax is
@example
- \context @var{type} = @var{id} @var{music}
+\context @var{type} = @var{id} @var{music}
@end example
This form will search for an existing context of type @var{type}
-called @var{id}. If that context does not exist yet, it is created.
-This is useful if the context is referred to later on. For example, when
+called @var{id}. If that context does not exist yet, a new
+context with the specified name is created. This is useful if
+the context is referred to later on. For example, when
setting lyrics the melody is in a named context
@example
- \context Voice = "@b{tenor}" @var{music}
+\context Voice = "@b{tenor}" @var{music}
@end example
@noindent
so the texts can be properly aligned to its notes,
@example
-\new Lyrics \lyricsto "@b{tenor}" @var{lyrics}
+\new Lyrics \lyricsto "@b{tenor}" @var{lyrics}
@end example
@noindent
-Another possibility is funneling two different music expressions into
-one context. In the following example, articulations and notes are
-entered separately,
+Another possible use of named contexts is funneling two different
+music expressions into one context. In the following example,
+articulations and notes are entered separately,
-@verbatim
-music = \notes { c4 c4 }
-arts = \notes { s4-. s4-> }
-@end verbatim
+@example
+music = @{ c4 c4 @}
+arts = @{ s4-. s4-> @}
+@end example
-They are combined by sending both to the same @context{Voice} context,
+They are combined by sending both to the same @code{Voice} context,
-@verbatim
- << \new Staff \context Voice = "A" \music
- \context Voice = "A" \arts
- >>
-@end verbatim
-@lilypond[raggedright]
-music = \notes { c4 c4 }
-arts = \notes { s4-. s4-> }
-\score {
- \notes \relative c'' << \new Staff \context Voice = "A" \music
- \context Voice = "A" \arts
- >>
-}
+@example
+<<
+ \new Staff \context Voice = "A" \music
+ \context Voice = "A" \arts
+>>
+@end example
+@lilypond[quote,ragged-right]
+music = { c4 c4 }
+arts = { s4-. s4-> }
+\relative c'' <<
+ \new Staff \context Voice = "A" \music
+ \context Voice = "A" \arts
+>>
@end lilypond
-@cindex @code{\context}
+With this mechanism, it is possible to define an Urtext (original
+edition), with the option to put several distinct articulations on the
+same notes.
+
@cindex creating contexts
+@item
The third command for creating contexts is
@example
- \context @var{type} @var{music}
+\context @var{type} @var{music}
@end example
any context of type @var{type}, regardless of its given name.
This variant is used with music expressions that can be interpreted at
-several levels. For example, the @code{\applyoutput} command (see
-@ref{Running a function on all layout objects}). Without an explicit
-@code{\context}, it is usually is applied to @context{Voice}
+several levels. For example, the @code{\applyOutput} command (see
+@ref{Running a function on all layout objects}). Without an explicit
+@code{\context}, it is usually applied to @code{Voice}
@example
- \applyoutput #@var{function} % apply to Voice
+\applyOutput #'@var{context} #@var{function} % apply to Voice
@end example
-To have it interpreted at the @context{Score} or @context{Staff} level use
+To have it interpreted at the @code{Score} or @code{Staff} level use
these forms
@example
- \context Score \applyoutput #@var{function}
- \context Staff \applyoutput #@var{function}
+\applyOutput #'Score #@var{function}
+\applyOutput #'Staff #@var{function}
@end example
+@end itemize
+
@node Changing context properties on the fly
@subsection Changing context properties on the fly
@cindex properties
-@cindex @code{\set}
+@funindex \set
@cindex changing properties
Each context can have different @emph{properties}, variables contained
-in that context. They can be changed during the interpretation step.
+in that context. They can be changed during the interpretation step.
This is achieved by inserting the @code{\set} command in the music,
-@quotation
- @code{\set } @var{context}@code{.}@var{prop}@code{ = #}@var{value}
-@end quotation
+@example
+\set @var{context}.@var{prop} = #@var{value}
+@end example
For example,
-@lilypond[verbatim,relative=2,fragment]
- R1*2
- \set Score.skipBars = ##t
- R1*2
+@lilypond[quote,verbatim,relative=2,fragment]
+R1*2
+\set Score.skipBars = ##t
+R1*2
@end lilypond
-This command skips measures that have no notes. The result is that
-multi rests are condensed. The value assigned is a Scheme object. In
+This command skips measures that have no notes. The result is that
+multi-rests are condensed. The value assigned is a Scheme object. In
this case, it is @code{#t}, the boolean True value.
If the @var{context} argument is left out, then the current bottom-most
-context (typically @context{ChordNames}, @context{Voice}, or
-@context{Lyrics}) is used. In this example,
+context (typically @code{ChordNames}, @code{Voice}, or
+@code{Lyrics}) is used. In this example,
-@lilypond[verbatim,relative=2,fragment]
- c8 c c c
- \set autoBeaming = ##f
- c8 c c c
+@lilypond[quote,verbatim,relative=2,fragment]
+c8 c c c
+\set autoBeaming = ##f
+c8 c c c
@end lilypond
@noindent
-the @var{context} argument to @code{\set} is left out, and the current
-@internalsref{Voice} is used.
+the @var{context} argument to @code{\set} is left out, so automatic
+beaming is switched off in the current @internalsref{Voice}. Note that
+the bottom-most context does not always contain the property that you
+wish to change -- for example, attempting to set the @code{skipBars}
+property (of the bottom-most context, in this case @code{Voice}) will
+have no effect.
+
+@lilypond[quote,verbatim,relative=2,fragment]
+R1*2
+\set skipBars = ##t
+R1*2
+@end lilypond
Contexts are hierarchical, so if a bigger context was specified, for
-example @context{Staff}, then the change would also apply to all
-@context{Voice}s in the current stave. The change is applied
-`on-the-fly', during the music, so that the setting only affects the
+example @code{Staff}, then the change would also apply to all
+@code{Voice}s in the current stave. The change is applied
+@q{on-the-fly}, during the music, so that the setting only affects the
second group of eighth notes.
-@cindex @code{\unset}
+@funindex \unset
There is also an @code{\unset} command,
-@quotation
- @code{\set }@var{context}@code{.}@var{prop}
-@end quotation
+@example
+\unset @var{context}.@var{prop}
+@end example
+
+@noindent
+which removes the definition of @var{prop}. This command removes
+the definition only if it is set in @var{context}, so
+
+@example
+\set Staff.autoBeaming = ##f
+@end example
@noindent
-which removes the definition of @var{prop}. This command removes
-the definition only if it is set in @var{context}. In
+introduces a property setting at @code{Staff} level. The setting also
+applies to the current @code{Voice}. However,
@example
- \set Staff.autoBeaming = ##f
- \unset Voice.autoBeaming
+\unset Voice.autoBeaming
@end example
@noindent
-the current @context{Voice} does not have the property, and the
-definition at @context{Staff} level remains intact. Like @code{\set},
-the @var{context} argument does not have to be specified for a bottom
-context.
+does not have any effect. To cancel this setting, the @code{\unset}
+must be specified on the same level as the original @code{\set}. In
+other words, undoing the effect of @code{Staff.autoBeaming = ##f}
+requires
+@example
+\unset Staff.autoBeaming
+@end example
+
+Like @code{\set}, the @var{context} argument does not have to be
+specified for a bottom context, so the two statements
+
+@example
+\set Voice.autoBeaming = ##t
+\set autoBeaming = ##t
+@end example
+
+@noindent
+are equivalent.
+
+@cindex \once
Settings that should only apply to a single time-step can be entered
-easily with @code{\once}, for example in
+with @code{\once}, for example in
-@lilypond[verbatim,relative=2,fragment]
- c4
- \once \set fontSize = #4.7
- c4
- c4
+@lilypond[quote,verbatim,relative=2,fragment]
+c4
+\once \set fontSize = #4.7
+c4
+c4
@end lilypond
the property @code{fontSize} is unset automatically after the second
A full description of all available context properties is in the
program reference, see
@ifhtml
-@internalsref{Tunable-context-properties}.
+@internalsref{Tunable context properties}.
@end ifhtml
@ifnothtml
-Translation @arrow{} Tunable context properties.
+Translation @expansion{} Tunable context properties.
@end ifnothtml
@node Modifying context plug-ins
@subsection Modifying context plug-ins
-Notation contexts (like Score and Staff) not only store properties,
-they also contain plug-ins, called ``engravers'' that create notation
-elements. For example, the Voice context contains a
-@code{Note_head_engraver} and the Staff context contains a
+Notation contexts (like @code{Score} and @code{Staff}) not only
+store properties,
+they also contain plug-ins called @q{engravers} that create notation
+elements. For example, the @code{Voice} context contains a
+@code{Note_head_engraver} and the @code{Staff} context contains a
@code{Key_signature_engraver}.
-For a full a description of each plug-in, see
+For a full a description of each plug-in, see
@ifhtml
@internalsref{Engravers}.
@end ifhtml
@ifnothtml
-Program reference @arrow Translation @arrow{} Engravers.
+Internals Reference @expansion{} Translation @expansion{} Engravers.
@end ifnothtml
Every context described in
@ifhtml
@internalsref{Contexts}
@end ifhtml
-@ifnothtml
-Program reference @arrow Translation @arrow{} Context.
+@ifnothtml
+Internals Reference @expansion{} Translation @expansion{} Context.
@end ifnothtml
lists the engravers used for that context.
-It can be useful to shuffle around these plug-ins. This is done by
-starting a new context, with @code{\new} or @code{\context}, and
-modifying it like this,
+It can be useful to shuffle around these plug-ins. This is done by
+starting a new context with @code{\new} or @code{\context}, and
+modifying it,
+
+@funindex \with
@example
- \new @var{context} \with @{
- \consists @dots{}
- \consists @dots{}
- \remove @dots{}
- \remove @dots{}
- @emph{etc.}
- @}
- @var{..music..}
+\new @var{context} \with @{
+ \consists @dots{}
+ \consists @dots{}
+ \remove @dots{}
+ \remove @dots{}
+ @emph{etc.}
+@}
+@{
+ @emph{..music..}
+@}
@end example
-where the @dots{} should be the name of an engraver. Here is a simple
+@noindent
+where the @dots{} should be the name of an engraver. Here is a simple
example which removes @code{Time_signature_engraver} and
@code{Clef_engraver} from a @code{Staff} context,
-@lilypond[relative=1, verbatim,fragment]
-<< \new Staff {
+@lilypond[quote,relative=1,verbatim,fragment]
+<<
+ \new Staff {
f2 g
}
\new Staff \with {
>>
@end lilypond
-In the second stave there are no time signature or clef symbols. This
+In the second staff there are no time signature or clef symbols. This
is a rather crude method of making objects disappear since it will affect
-the entire staff. The spacing will be adversely influenced too. A more
-sophisticated methods of blanking objects is shown in @ref{Common
-tweaks}.
+the entire staff. This method also influences the spacing, which may or
+may not be desirable. A more
+sophisticated method of blanking objects is shown in @rlearning{Common tweaks}.
The next example shows a practical application. Bar lines and time
signatures are normally synchronized across the score. This is done
-by the @code{Timing_engraver}. This plug-in keeps an administration of
-time signature, location within the measure, etc. By moving the
-@code{Timing_engraver} engraver from Score to Staff context, we can
-have a score where each staff has its own time signature.
+by the @code{Timing_translator} and @code{Default_bar_line_engraver}.
+This plug-in keeps an administration of time signature, location
+within the measure, etc. By moving thes engraver from @code{Score} to
+@code{Staff} context, we can have a score where each staff has its own
+time signature.
@cindex polymetric scores
+@cindex Time signatures, multiple
-
-@lilypond[relative=1,raggedright,verbatim,fragment]
+@lilypond[quote,relative=1,ragged-right,verbatim,fragment]
\new Score \with {
- \remove "Timing_engraver"
+ \remove "Timing_translator"
+ \remove "Default_bar_line_engraver"
} <<
\new Staff \with {
- \consists "Timing_engraver"
+ \consists "Timing_translator"
+ \consists "Default_bar_line_engraver"
} {
\time 3/4
c4 c c c c c
}
\new Staff \with {
- \consists "Timing_engraver"
+ \consists "Timing_translator"
+ \consists "Default_bar_line_engraver"
} {
\time 2/4
c4 c c c c c
@subsection Layout tunings within contexts
Each context is responsible for creating certain types of graphical
-objects. The settings used for printing these objects are also stored by
-context. By changing these settings, the appearance of objects can be
+objects. The settings used for printing these objects are also stored by
+context. By changing these settings, the appearance of objects can be
altered.
-
+
The syntax for this is
@example
- \override @var{context}.@var{name}@code{ #'}@var{property} = #@var{value}
+\override @var{context}.@var{name} #'@var{property} = #@var{value}
@end example
Here @var{name} is the name of a graphical object, like @code{Stem} or
@code{NoteHead}, and @var{property} is an internal variable of the
-formatting system (`grob property' or `layout property'). The latter is a
-symbol, so it must be quoted. The subsection @ref{Constructing a
-tweak} explains what to fill in for @var{name}, @var{property}, and
-@var{value}. Here we only discuss functionality of this command.
+formatting system (@q{grob property} or @q{layout property}). The latter is a
+symbol, so it must be quoted. The subsection @ref{Constructing a
+tweak}, explains what to fill in for @var{name}, @var{property}, and
+@var{value}. Here we only discuss the functionality of this command.
The command
@verbatim
- \override Staff.Stem #'thickness = #4.0
+\override Staff.Stem #'thickness = #4.0
@end verbatim
@noindent
makes stems thicker (the default is 1.3, with staff line thickness as a
-unit). Since the command specifies @context{Staff} as context, it only
-applies to the current staff. Other staves will keep their normal
+unit). Since the command specifies @code{Staff} as context, it only
+applies to the current staff. Other staves will keep their normal
appearance. Here we see the command in action:
-@lilypond[verbatim,relative=2,fragment]
- c4
- \override Staff.Stem #'thickness = #4.0
- c4
- c4
- c4
+@lilypond[quote,verbatim,relative=2,fragment]
+c4
+\override Staff.Stem #'thickness = #4.0
+c4
+c4
+c4
@end lilypond
-The @code{\override} command is executed during the interpreting phase,
-and changes the definition of the @code{Stem} within
-@context{Staff}. After the command all stems are thickened.
+The @code{\override} command changes the definition of the @code{Stem}
+within the current @code{Staff}. After the command is interpreted
+all stems are thickened.
Analogous to @code{\set}, the @var{context} argument may be left out,
-causing it to default to @context{Voice}, and adding @code{\once} applies
-the change during one timestep only
-
-@lilypond[fragment,verbatim,relative=2]
- c4
- \once \override Stem #'thickness = #4.0
- c4
- c4
+causing the default context @code{Voice} to be used. Adding
+@code{\once} applies the change during one timestep only.
+
+@lilypond[quote,fragment,verbatim,relative=2]
+c4
+\once \override Stem #'thickness = #4.0
+c4
+c4
@end lilypond
The @code{\override} must be done before the object is
-started. Therefore, when altering @emph{Spanner} objects, like slurs or
-beams, the @code{\override} command must be executed at the moment when
-the object is created. In this example,
-
-
-@lilypond[fragment,verbatim,relative=2]
- \override Slur #'thickness = #3.0
- c8[( c
- \override Beam #'thickness = #0.6
- c8 c])
+started. Therefore, when altering @emph{Spanner} objects such as slurs
+or beams, the @code{\override} command must be executed at the moment
+when the object is created. In this example,
+
+@lilypond[quote,fragment,verbatim,relative=2]
+\override Slur #'thickness = #3.0
+c8[( c
+\override Beam #'thickness = #0.6
+c8 c])
@end lilypond
@noindent
-the slur is fatter and the beam is not. This is because the command for
-@code{Beam} comes after the Beam is started. Therefore it has no effect.
+the slur is fatter but the beam is not. This is because the command for
+@code{Beam} comes after the Beam is started, so it has no effect.
Analogous to @code{\unset}, the @code{\revert} command for a context
-undoes a @code{\override} command; like with @code{\unset}, it only
-affects settings that were made in the same context. In other words, the
+undoes an @code{\override} command; like with @code{\unset}, it only
+affects settings that were made in the same context. In other words, the
@code{\revert} in the next example does not do anything.
-@verbatim
- \override Voice.Stem #'thickness = #4.0
- \revert Staff.Stem #'thickness
-@end verbatim
+@example
+\override Voice.Stem #'thickness = #4.0
+\revert Staff.Stem #'thickness
+@end example
+
+Some tweakable options are called @q{subproperties} and reside inside
+properties. To tweak those, use commands of the form
+@c leave this as a long long
+@example
+\override @var{context}.@var{name} #'@var{property} #'@var{subproperty} = #@var{value}
+@end example
+
+@noindent
+such as
+@example
+\override Stem #'details #'beamed-lengths = #'(4 4 3)
+@end example
@seealso
Internals: @internalsref{OverrideProperty}, @internalsref{RevertProperty},
-@internalsref{PropertySet}, @internalsref{All-backend-properties}, and
-@internalsref{All-layout-objects}.
+@internalsref{PropertySet}, @internalsref{Backend}, and
+@internalsref{All layout objects}.
@refbugs
@node Changing context default settings
@subsection Changing context default settings
-The adjustments of the previous chapters can also be entered separate
-from the music, in the @code{\paper} block,
+The adjustments of the previous subsections (@ref{Changing context
+properties on the fly}, @ref{Modifying context plug-ins}, and
+@ref{Layout tunings within contexts}) can also be entered separately
+from the music in the @code{\layout} block,
@example
- \paper @{
- @dots{}
- \context @{
- \Staff
-
- \set fontSize = #-2
- \override Stem #'thickness
- \remove "Time_signature_engraver"
- @}
- @}
-@end example
+\layout @{
+ @dots{}
+ \context @{
+ \Staff
-Here
-@example
- \Staff
+ \set fontSize = #-2
+ \override Stem #'thickness = #4.0
+ \remove "Time_signature_engraver"
+ @}
+@}
@end example
-@noindent
-takes the existing definition @context{Staff} from the identifier
-@code{Staff}. This works analogously to other contexts.
+The @code{\Staff} command brings in the existing definition of the
+staff context so that it can be modified.
The statements
@example
- \set fontSize = #-2
- \override Stem #'thickness
- \remove "Time_signature_engraver"
+\set fontSize = #-2
+\override Stem #'thickness = #4.0
+\remove "Time_signature_engraver"
@end example
@noindent
-affect all staves in the score.
+affect all staves in the score. Other contexts can be modified
+analogously.
-The @code{\set} keyword is optional within the @code{\paper} block, so
+The @code{\set} keyword is optional within the @code{\layout} block, so
@example
+\context @{
+ @dots{}
fontSize = #-2
+@}
@end example
@noindent
@refbugs
-It is not possible to collect changes in a variable, and apply them to
-one @code{\context} definition by referring to that variable.
+It is not possible to collect context changes in a variable and apply
+them to a @code{\context} definition by referring to that variable.
+
+The @code{\RemoveEmptyStaffContext} will overwrite your current
+@code{\Staff} settings. If you wish to change the defaults for a
+staff which uses @code{\RemoveEmptyStaffContext}, you must do so
+after calling @code{\RemoveEmptyStaffContext}, ie
+@example
+\layout @{
+ \context @{
+ \RemoveEmptyStaffContext
+
+ \override Stem #'thickness = #4.0
+ @}
+@}
+@end example
-@node Defining new contexts
-@subsection Defining new contexts
-Specific contexts, like @context{Staff} and @code{Voice}, are made of
-simple building blocks, and it is possible to compose engraver
-plug-ins in different combinations, thereby creating new types of
-contexts.
+@node Defining new contexts
+@subsection Defining new contexts
+
+Specific contexts, like @code{Staff} and @code{Voice}, are made of
+simple building blocks. It is possible to create new types of
+contexts with different combinations of engraver plug-ins.
The next example shows how to build a different type of
-@context{Voice} context from scratch. It will be similar to
-@code{Voice}, but print centered slash noteheads only. It can be used
-to indicate improvisation in Jazz pieces,
+@code{Voice} context from scratch. It will be similar to
+@code{Voice}, but only prints centered slash note heads. It can be used
+to indicate improvisation in jazz pieces,
-@lilypond[raggedright]
- \paper { \context {
- \name ImproVoice
- \type "Engraver_group_engraver"
- \consists "Note_heads_engraver"
- \consists "Text_engraver"
- \consists Pitch_squash_engraver
- squashedPosition = #0
- \override NoteHead #'style = #'slash
- \override Stem #'transparent = ##t
- \alias Voice
- }
- \context { \Staff
- \accepts "ImproVoice"
- }}
- \score { \notes \relative c'' {
- a4 d8 bes8 \new ImproVoice { c4^"ad lib" c
- c4 c^"undress" c_"while playing :)" c }
- a1
- }}
+@lilypond[quote,ragged-right]
+\layout { \context {
+ \name ImproVoice
+ \type "Engraver_group"
+ \consists "Note_heads_engraver"
+ \consists "Text_engraver"
+ \consists Pitch_squash_engraver
+ squashedPosition = #0
+ \override NoteHead #'style = #'slash
+ \override Stem #'transparent = ##t
+ \alias Voice
+}
+\context { \Staff
+ \accepts "ImproVoice"
+}}
+
+\relative c'' {
+ a4 d8 bes8 \new ImproVoice { c4^"ad lib" c
+ c4 c^"undress" c_"while playing :)" c }
+ a1
+}
@end lilypond
-These settings are again done within a @code{\context} block inside a
-@code{\paper} block,
+These settings are defined within a @code{\context} block inside a
+@code{\layout} block,
@example
- \paper @{
- \context @{
- @dots{}
- @}
+\layout @{
+ \context @{
+ @dots{}
@}
+@}
@end example
-In the following discussion, the example input shown should go on the
-@dots{} in the previous fragment.
+In the following discussion, the example input shown should go in place
+of the @dots{} in the previous fragment.
-First, name the context gets a name. Instead of @context{Voice} it
-will be called @context{ImproVoice},
+First it is necessary to define a name for the new context:
-@verbatim
- \name ImproVoice
-@end verbatim
+@example
+\name ImproVoice
+@end example
-Since it is similar to the @context{Voice}, we want commands that work
-on (existing) @context{Voice}s to remain working. This is achieved by
-giving the new context an alias @context{Voice},
+Since it is similar to the @code{Voice}, we want commands that work
+on (existing) @code{Voice}s to remain working. This is achieved by
+giving the new context an alias @code{Voice},
-@verbatim
- \alias Voice
-@end verbatim
+@example
+\alias Voice
+@end example
-The context will print notes, and instructive texts
+The context will print notes and instructive texts, so we need to add
+the engravers which provide this functionality,
-@verbatim
- \consists Note_heads_engraver
- \consists Text_engraver
-@end verbatim
+@example
+\consists Note_heads_engraver
+\consists Text_engraver
+@end example
-but only on the center line,
+but we only need this on the center line,
-@verbatim
- \consists Pitch_squash_engraver
- squashedPosition = #0
-@end verbatim
+@example
+\consists Pitch_squash_engraver
+squashedPosition = #0
+@end example
The @internalsref{Pitch_squash_engraver} modifies note heads (created
by @internalsref{Note_heads_engraver}) and sets their vertical
-position to the value of @code{squashedPosition}, in this case
-@code{0}, the center line.
-
-The notes look like a slash, without a stem,
+position to the value of @code{squashedPosition}, in this case@tie{}@code{0},
+the center line.
-@verbatim
- \override NoteHead #'style = #'slash
- \override Stem #'transparent = ##t
-@end verbatim
+The notes look like a slash, and have no stem,
+@example
+\override NoteHead #'style = #'slash
+\override Stem #'transparent = ##t
+@end example
All these plug-ins have to cooperate, and this is achieved with a
special plug-in, which must be marked with the keyword @code{\type}.
-This should always be @internalsref{Engraver_group_engraver},
+This should always be @internalsref{Engraver_group},
@example
- \type "Engraver_group_engraver"
+\type "Engraver_group"
@end example
-Putting together, we get
+Put together, we get
-@verbatim
- \context {
- \name ImproVoice
- \type "Engraver_group_engraver"
- \consists "Note_heads_engraver"
- \consists "Text_script_engraver"
- \consists Pitch_squash_engraver
- squashedPosition = #0
- \override NoteHead #'style = #'slash
- \override Stem #'transparent = ##t
- \alias Voice
- }
-@end verbatim
+@example
+\context @{
+ \name ImproVoice
+ \type "Engraver_group"
+ \consists "Note_heads_engraver"
+ \consists "Text_engraver"
+ \consists Pitch_squash_engraver
+ squashedPosition = #0
+ \override NoteHead #'style = #'slash
+ \override Stem #'transparent = ##t
+ \alias Voice
+@}
+@end example
-Contexts form hierarchies. We want to hang the @context{ImproVoice}
-under @context{Staff}, just like normal @code{Voice}s. Therefore, we
+@funindex \accepts
+Contexts form hierarchies. We want to hang the @code{ImproVoice}
+under @code{Staff}, just like normal @code{Voice}s. Therefore, we
modify the @code{Staff} definition with the @code{\accepts}
-command,@footnote{The opposite of @code{\accepts} is @code{\denies},
-which is sometimes when reusing existing context definitions. }
-
+command,
+@example
+\context @{
+ \Staff
+ \accepts ImproVoice
+@}
+@end example
-@verbatim
- \context {
- \Staff
- \accepts ImproVoice
- }
-@end verbatim
+@funindex \denies
+The opposite of @code{\accepts} is @code{\denies},
+which is sometimes needed when reusing existing context definitions.
-Putting both into a @code{\paper} block, like
+Putting both into a @code{\layout} block, like
@example
- \paper @{
- \context @{
- \name ImproVoice
- @dots{}
- @}
+\layout @{
+ \context @{
+ \name ImproVoice
+ @dots{}
+ @}
\context @{
\Staff
\accepts "ImproVoice"
Then the output at the start of this subsection can be entered as
-@verbatim
-\score {
- \notes \relative c'' {
- a4 d8 bes8
- \new ImproVoice {
- c4^"ad lib" c
- c4 c^"undress"
- c c_"while playing :)"
- }
- a1
- }
-}
-@end verbatim
-
-
-
-@node Which properties to change
-@subsection Which properties to change
+@example
+\relative c'' @{
+ a4 d8 bes8
+ \new ImproVoice @{
+ c4^"ad lib" c
+ c4 c^"undress"
+ c c_"while playing :)"
+ @}
+ a1
+@}
+@end example
-There are many different properties. Not all of them are listed in
-this manual. However, the program reference lists them all in the
-section @internalsref{Tunable-context-properties}, and most properties
-are demonstrated in one of the
-@ifhtml
-@uref{../../../../input/test/out-www/collated-files.html,tips-and-tricks}
-@end ifhtml
-@ifnothtml
-tips-and-tricks
-@end ifnothtml
-examples.
+@node Aligning contexts
+@subsection Aligning contexts
+New contexts may be aligned above or below exisiting contexts. This
+could be useful in setting up a vocal staff (@rlearning{Vocal ensembles}) and
+in ossia,
-@node Tuning output
-@section Tuning output
+FIXME: this section doens't work in pdf. (?)
-In the previous section, we have already touched on a command that
-changes layout details, the @code{\override} command. In this section,
-we will look at in more detail how to use the command in practice.
-First, we will give a a few versatile commands, which are sufficient
-for many situations. The next section will discuss general use of
-@code{\override}.
+@cindex ossia
+@findex alignAboveContext
+@findex alignBelowContext
-@ignore
-There are situations where default layout decisions are not
-sufficient. In this section we discuss ways to override these
-defaults.
-
-Formatting is internally done by manipulating so called objects
-(graphic objects). Each object carries with it a set of properties
-(object or layout properties) specific to the object. For example, a
-stem object has properties that specify its direction, length, and
-thickness.
-
-The most direct way of tuning the output is to alter the values of
-these properties. There are two ways of doing that: First, you can
-temporarily change the definition of one type of object, thus
-affecting a whole set of objects. Second, you can select one specific
-object, and set a layout property in that object.
-
-Do not confuse layout properties with translation
-properties. Translation properties always use a mixed caps style
-naming, and are manipulated using @code{\set} and @code{\unset}:
-@example
- \set Context.propertyName = @var{value}
-@end example
+@lilypond[quote,ragged-right]
+ossia = { f4 f f f }
+\score{
+ \relative c' \new Staff = "main" {
+ c4 c c c
+ <<
+ \new Staff \with {alignAboveContext=main} \ossia
+ { d8 f d f d f d f }
+ >>
+ }
+}
+@end lilypond
+
+
+@node Vertical grouping of grobs
+@subsection Vertical grouping of grobs
+
+The VerticalAlignment and VerticalAxisGroup grobs work together.
+VerticalAxisGroup groups together different grobs like Staff, Lyrics,
+etc. VerticalAlignment then vertically aligns the different grobs
+grouped together by VerticalAxisGroup. There is usually only one
+VerticalAlignment per score but every Staff, Lyrics, etc. has its own
+VerticalAxisGroup.
+
+
+@node The \override command
+@section The @code{\override} command
+
+In the previous section, we have already touched on a command that
+changes layout details: the @code{\override} command. In this section,
+we will look in more detail at how to use the command in practice. The
+general syntax of this command is:
-Layout properties are use Scheme style variable naming, i.e. lower
-case words separated with dashes. They are symbols, and should always
-be quoted using @code{#'}. For example, this could be an imaginary
-layout property name:
@example
- #'layout-property-name
+\override @var{context}.@var{layout_object} #'@var{layout_property} = #@var{value}
@end example
-@end ignore
+This will set the @var{layout_property} of the specified @var{layout_object},
+which is a member of the @var{context}, to the @var{value}.
@menu
-* Common tweaks::
* Constructing a tweak::
* Navigating the program reference::
* Layout interfaces::
* Determining the grob property::
+* Objects connected to the input::
+* Using Scheme code instead of \tweak::
+* \set versus \override::
+* Difficult tweaks::
@end menu
-@node Common tweaks
-@subsection Common tweaks
-
-Some overrides are so common that predefined commands are provided as
-a short-cut, for example, @code{\slurUp} and @code{\stemDown}. These
-commands are described in
-@ifhtml
-the
-@end ifhtml
-@ref{Notation manual}, under the sections for slurs and stems
-respectively.
-
-The exact tuning possibilities for each type of layout object are
-documented in the program reference of the respective
-object. However, many layout objects share properties, which can be
-used to apply generic tweaks. We mention a few of these:
-
-@itemize @bullet
-@item The @code{extra-offset} property, which
-@cindex @code{extra-offset}
-has a pair of numbers as value, moves around objects in the printout.
-The first number controls left-right movement; a positive number will
-move the object to the right. The second number controls up-down
-movement; a positive number will move it higher. The units of these
-offsets are staff-spaces. The @code{extra-offset} property is a
-low-level feature: the formatting engine is completely oblivious to
-these offsets.
-
-In the following example, the second fingering is moved a little to
-the left, and 1.8 staff space downwards:
-
-@cindex setting object properties
-
-@lilypond[fragment,relative=1,verbatim]
-\stemUp
-f-5
-\once \override Fingering
- #'extra-offset = #'(-0.3 . -1.8)
-f-5
-@end lilypond
-
-@item
-Setting the @code{transparent} property will cause an object to be printed
-in `invisible ink': the object is not printed, but all its other
-behavior is retained. The object still takes up space, it takes part in
-collisions, and slurs, and ties and beams can be attached to it.
-
-@cindex transparent objects
-@cindex removing objects
-@cindex hiding objects
-@cindex invisible objects
-The following example demonstrates how to connect different voices
-using ties. Normally, ties only connect two notes in the same
-voice. By introducing a tie in a different voice,
-
-@lilypond[fragment,relative=2]
- << {
- b8~ b8\noBeam
- } \\ {
- b[ g8]
- } >>
-@end lilypond
-
-@noindent
-and blanking a stem in that voice, the tie appears to cross voices:
-
-@lilypond[fragment,relative=2,verbatim]
- << {
- \once \override Stem #'transparent = ##t
- b8~ b8\noBeam
- } \\ {
- b[ g8]
- } >>
-@end lilypond
-
-@item
-The @code{padding} property for objects with
-@cindex @code{padding}
-@code{side-position-interface} can be set to increase distance between
-symbols that are printed above or below notes. We only give an
-example; a more elaborate explanation is in @ref{Constructing a
-tweak}:
-
-@lilypond[fragment,relative=1,verbatim]
- c2\fermata
- \override Script #'padding = #3
- b2\fermata
-@end lilypond
-
-@end itemize
-
-More specific overrides are also possible. The next section
-discusses in depth how to figure out these statements for yourself.
-
-
@node Constructing a tweak
@subsection Constructing a tweak
-The general procedure of changing output, that is, entering
-a command like
+Commands which change output generally look like
@example
- \override Voice.Stem #'thickness = #3.0
+\override Voice.Stem #'thickness = #3.0
@end example
@noindent
-means that we have to determine these bits of information:
+To construct this tweak we must determine these bits of information:
@itemize
-@item the context: here @context{Voice}.
+@item the context: here @code{Voice}.
@item the layout object: here @code{Stem}.
-@item the layout property: here @code{thickness}
-@item a sensible value: here @code{3.0}
-@end itemize
+@item the layout property: here @code{thickness}.
+@item a sensible value: here @code{3.0}.
+@end itemize
+
+Some tweakable options are called @q{subproperties} and reside inside
+properties. To tweak those, use commands in the form
+@example
+\override Stem #'details #'beamed-lengths = #'(4 4 3)
+@end example
@cindex internal documentation
@cindex finding graphical objects
-@cindex graphical object descriptions
+@cindex graphical object descriptions
@cindex tweaking
-@cindex @code{\override}
-@cindex @code{\set}
+@funindex \override
@cindex internal documentation
+For many properties, regardless of the data type of the property, setting the
+property to false ( @code{##f} ) will result in turning it off, causing
+Lilypond to ignore that property entirely. This is particularly useful for
+turning off grob properties which may otherwise be causing problems.
+
We demonstrate how to glean this information from the notation manual
and the program reference.
-The program reference is a set of HTML pages, which is part of the
-documentation package. On Unix systems, it is typically in
-@file{/usr/share/doc/lilypond}. If you have them, it is best to
-bookmark them in your webbrowser, because you will need them. They
-are also available on the web: go to the
-@uref{http://lilypond.org,LilyPond website}, click ``Documentation'',
-select the correct version, and then click ``Program reference.''
-If you have them, use the local HTML files. They will load faster,
-and they are exactly matched to LilyPond version installed.
-
+
@node Navigating the program reference
@subsection Navigating the program reference
Suppose we want to move the fingering indication in the fragment
below:
-@lilypond[fragment,relative=2,verbatim]
+@lilypond[quote,fragment,relative=2,verbatim]
c-2
\stemUp
f
@end lilypond
-If you visit the documentation of @code{Fingering} (in @ref{Fingering
-instructions}), you will notice that there is written:
+If you visit the documentation on fingering instructions (in
+@ref{Fingering instructions}), you will notice:
@quotation
@seealso
-Program reference: @internalsref{FingerEvent} and @internalsref{Fingering}.
+Internals Reference: @internalsref{Fingering}.
@end quotation
-This fragments points to two parts of the program reference: a page
-on @code{FingerEvent} and on @code{Fingering}.
-The page on @code{FingerEvent} describes the properties of the music
-expression for the input @code{-2}. The page contains many links
+@c outdated info; probably will delete.
+@ignore
+This fragment points to two parts of the program reference: a page
+on @code{FingerEvent} and one on @code{Fingering}.
+
+The page on @code{FingerEvent} describes the properties of the music
+expression for the input @code{-2}. The page contains many links
forward. For example, it says
@quotation
- Accepted by: @internalsref{Fingering_engraver},
-@end quotation
+Accepted by: @internalsref{Fingering_engraver},
+@end quotation
@noindent
That link brings us to the documentation for the Engraver, the
plug-in, which says
@quotation
- This engraver creates the following layout objects: @internalsref{Fingering}.
+This engraver creates the following layout objects: @internalsref{Fingering}.
@end quotation
In other words, once the @code{FingerEvent}s are interpreted, the
@code{Fingering_engraver} plug-in will process them.
+@end ignore
+
+@ignore
+@c I can't figure out what this is supposed to mean. -gp
+
The @code{Fingering_engraver} is also listed to create
@internalsref{Fingering} objects,
-
- Lo and behold, that is also the
+@c old info? it doesn't make any sense to me with our current docs.
+This is also the
second bit of information listed under @b{See also} in the Notation
-manual. By clicking around in the program reference, we can follow the
-flow of information within the program, either forward (like we did
-here), or backwards, following links like this:
+manual.
+@end ignore
-@itemize @bullet
+@ifnothtml
+The programmer's reference is available as an HTML document. It is
+highly recommended that you read it in HTML form, either online or
+by downloading the HTML documentation. This section will be much more
+difficult to understand if you are using the
+PDF manual.
+@end ifnothtml
+
+Follow the link to @internalsref{Fingering}. At the top of the
+page, you will see
+
+@quotation
+Fingering objects are created by: @internalsref{Fingering_engraver} and
+@internalsref{New_fingering_engraver}.
+@end quotation
+
+By following related links inside the program reference, we can follow the
+flow of information within the program:
+
+@itemize
@item @internalsref{Fingering}:
- @internalsref{Fingering} objects are created by:
- @b{@internalsref{Fingering_engraver}}
+@internalsref{Fingering} objects are created by:
+@internalsref{Fingering_engraver}
@item @internalsref{Fingering_engraver}:
-Music types accepted: @b{@internalsref{fingering-event}}
+Music types accepted: @internalsref{fingering-event}
+
@item @internalsref{fingering-event}:
-Music event type @code{fingering-event} is in Music objects of type
-@b{@internalsref{FingerEvent}}
+Music event type @code{fingering-event} is in Music expressions named
+@internalsref{FingerEvent}
@end itemize
This path goes against the flow of information in the program: it
-starts from the output, and ends at the input event.
+starts from the output, and ends at the input event. You could
+also start at an input event, and read with the flow of
+information, eventually ending up at the output object(s).
The program reference can also be browsed like a normal document. It
-contains a chapter on
+contains chapters on
@ifhtml
-@internalsref{Music-definitions},
+@internalsref{Music definitions},
@end ifhtml
@ifnothtml
-Music definitions
+@code{Music definitions}
@end ifnothtml
-on @internalsref{Translation}, and the @internalsref{Backend}. Every
-chapter lists all the definitions used, and all properties that may be
+on @internalsref{Translation}, and the @internalsref{Backend}. Every
+chapter lists all the definitions used and all properties that may be
tuned.
-
+
@node Layout interfaces
@subsection Layout interfaces
-@internalsref{Fingering} is a layout object. Such an object is a
-symbol within the score. It has properties, which store numbers (like
-thicknesses and directions), but also pointers to related objects.
-A layout object is also called @emph{grob},
+@cindex interface, layout
+@cindex layout interface
@cindex grob
-which is short for Graphical Object.
+The HTML page that we found in the previous section describes the
+layout object called @internalsref{Fingering}. Such an object is a
+symbol within the score. It has properties that store numbers (like
+thicknesses and directions), but also pointers to related objects. A
+layout object is also called a @emph{Grob}, which is short for Graphical
+Object. For more details about Grobs, see @internalsref{grob-interface}.
The page for @code{Fingering} lists the definitions for the
-@code{Fingering} object. For example, the page says
+@code{Fingering} object. For example, the page says
@quotation
- @code{padding} (dimension, in staff space):
-
- @code{0.6}
+@code{padding} (dimension, in staff space):
+
+@code{0.5}
@end quotation
-which means that the number will be kept at a distance of at least 0.6
+@noindent
+which means that the number will be kept at a distance of at least 0.5
of the note head.
Each layout object may have several functions as a notational or
-typographical element. For example, the Fingering object
+typographical element. For example, the Fingering object
has the following aspects
-@itemize @bullet
-@item Its size is independent of the horizontal spacing, unlike slurs or beams
+@itemize
+@item
+Its size is independent of the horizontal spacing, unlike slurs or beams.
-@item It is a piece of text. Granted, it's usually a very short text.
+@item
+It is a piece of text. Granted, it is usually a very short text.
+
+@item
+That piece of text is typeset with a font, unlike slurs or beams.
-@item That piece of text is typeset with a font, unlike slurs or beams.
-@item Horizontally, the center of the symbol should be aligned to the
-center of the notehead
-@item Vertically, the symbol is placed next to the note and the staff.
+@item
+Horizontally, the center of the symbol should be aligned to the
+center of the note head.
-@item The
- vertical position is also coordinated with other super and subscript
-symbols
+@item
+Vertically, the symbol is placed next to the note and the staff.
+
+@item
+The vertical position is also coordinated with other superscript
+and subscript symbols.
@end itemize
-Each of these aspects is captured in a so-called @emph{interface},
+Each of these aspects is captured in so-called @emph{interface}s,
which are listed on the @internalsref{Fingering} page at the bottom
@quotation
Clicking any of the links will take you to the page of the respective
object interface. Each interface has a number of properties. Some of
-them are not user-serviceable (``Internal properties''), but others
-are.
+them are not user-serviceable (@q{Internal properties}), but others
+can be modified.
-We have been talking of `the' @code{Fingering} object, but actually it
-does not amount to much. The initialization file
-@file{scm/define-grobs.scm} shows the soul of the `object',
+We have been talking of @emph{the} @code{Fingering} object, but actually it
+does not amount to much. The initialization file (see
+@rlearning{Default files})
+@file{scm/@/define@/-grobs@/.scm} shows the soul of the @q{object},
-@verbatim
- (Fingering
- . (
- (print-function . ,Text_item::print)
- (padding . 0.6)
- (staff-padding . 0.6)
- (self-alignment-X . 0)
- (self-alignment-Y . 0)
- (script-priority . 100)
- (font-encoding . number)
- (font-size . -5)
- (meta . ((interfaces . (finger-interface font-interface
- text-script-interface text-interface
- side-position-interface self-alignment-interface
- item-interface))))
- ))
-@end verbatim
+@example
+(Fingering
+ . ((padding . 0.5)
+ (avoid-slur . around)
+ (slur-padding . 0.2)
+ (staff-padding . 0.5)
+ (self-alignment-X . 0)
+ (self-alignment-Y . 0)
+ (script-priority . 100)
+ (stencil . ,ly:text-interface::print)
+ (direction . ,ly:script-interface::calc-direction)
+ (font-encoding . fetaNumber)
+ (font-size . -5) ; don't overlap when next to heads.
+ (meta . ((class . Item)
+ (interfaces . (finger-interface
+ font-interface
+ text-script-interface
+ text-interface
+ side-position-interface
+ self-alignment-interface
+ item-interface))))))
+@end example
+
+@noindent
+As you can see, the @code{Fingering} object is nothing more than a
+bunch of variable settings, and the webpage in the Internals Reference
+is directly generated from this definition.
-as you can see, @code{Fingering} is nothing more than a bunch of
-variable settings, and the webpage is directly generated from this
-definition.
@node Determining the grob property
@subsection Determining the grob property
+Recall that we wanted to change the position of the @b{2} in
-Recall that we wanted to change the position of the @b{2} in
-
-@lilypond[fragment,relative=2,verbatim]
+@lilypond[quote,fragment,relative=2,verbatim]
c-2
\stemUp
f
@end lilypond
Since the @b{2} is vertically positioned next to its note, we have to
-meddle with the interface associated with this positioning. This is
-done using @code{side-position-interface}. The page for this interface
+meddle with the interface associated with this positioning. This is
+done using @code{side-position-interface}. The page for this interface
says
@quotation
@code{side-position-interface}
- Position a victim object (this one) next to other objects (the
- support). The property @code{direction} signifies where to put the
- victim object relative to the support (left or right, up or down?)
+Position a victim object (this one) next to other objects (the
+support). The property @code{direction} signifies where to put the
+victim object relative to the support (left or right, up or down?)
@end quotation
@cindex padding
@noindent
-below this description, the variable @code{padding} is described as
+Below this description, the variable @code{padding} is described as
+
@quotation
@table @code
@item padding
- (dimension, in staff space)
+(dimension, in staff space)
- add this much extra space between objects that are next to each
- other.
+Add this much extra space between objects that are next to each other.
@end table
@end quotation
-By increasing the value of @code{padding}, we can move away the
-fingering. The following command inserts 3 staff spaces of white
+By increasing the value of @code{padding}, we can move the
+fingering away from the note head. The following command inserts
+3 staff spaces of white
between the note and the fingering:
@example
-\once \override Fingering #'padding = #3
+\once \override Voice.Fingering #'padding = #3
@end example
Inserting this command before the Fingering object is created,
-i.e. before @code{c2}, yields the following result:
+i.e., before @code{c2}, yields the following result:
-@lilypond[relative=2,fragment,verbatim]
-\once \override Fingering
- #'padding = #3
+@lilypond[quote,relative=2,fragment,verbatim]
+\once \override Voice.Fingering #'padding = #3
c-2
\stemUp
f
@end lilypond
-In this case, the context for this tweak is @context{Voice}, which
-does not have to be specified for @code{\override}. This fact can
-also be deduced from the program reference, for the page for the
-@internalsref{Fingering_engraver} plug-in says
+In this case, the context for this tweak is @code{Voice}. This
+fact can also be deduced from the program reference, for the page for
+the @internalsref{Fingering_engraver} plug-in says
@quotation
- Fingering_engraver is part of contexts: @dots{} @b{@internalsref{Voice}}
+Fingering_engraver is part of contexts: @dots{} @internalsref{Voice}
@end quotation
-@node Fonts
-@section Fonts
-
-@menu
-* Selecting font sizes::
-* Font selection::
-@end menu
-
+@node Objects connected to the input
+@subsection Objects connected to the input
+@funindex \tweak
-@node Selecting font sizes
-@subsection Selecting font sizes
+In some cases, it is possible to take a short-cut for tuning graphical
+objects. For objects that result directly from a piece of the input,
+you can use the @code{\tweak} function, for example
-The most common thing to change about the appearance of fonts is their
-size. The font size of any context can be easily changed by setting
-the @code{fontSize} property for that context. Its value is a number:
-negative numbers make the font smaller, positive numbers larger. An
-example is given below:
-@c
-@lilypond[fragment,relative=1,verbatim]
- c4 c4 \set fontSize = #-3
- f4 g4
+@lilypond[relative=2,fragment,verbatim,ragged-right]
+<
+ c
+ \tweak #'color #red d
+ g
+ \tweak #'duration-log #1 a
+>4-\tweak #'padding #10 -.
@end lilypond
-This command will set @code{font-size} (see below) in all layout
-objects in the current context. It does not change the size of
-variable symbols, such as beams or slurs.
-
-The font size is set by modifying the @code{font-size} property. Its
-value is a number indicating the size relative to the standard size.
-Each step up is an increase of approximately 12% of the font size. Six
-steps is exactly a factor two. The Scheme function @code{magstep}
-converts a @code{font-size} number to a scaling factor.
-
-LilyPond has fonts in different design sizes: the music fonts for
-smaller sizes are chubbier, while the text fonts are relatively wider.
-Font size changes are achieved by scaling the design size that is
-closest to the desired size.
-
-The @code{font-size} mechanism does not work for fonts selected
-through @code{font-name}. These may be scaled with
-@code{font-magnification}.
-
-
-One of the uses of @code{fontSize} is to get smaller symbols for cue
-notes. An elaborate example of those is in
-@inputfileref{input/test,cue-notes.ly}.
-@cindex cue notes
-@cindex @code{font-style}
+As you can see, properties are set in the objects directly,
+without mentioning the grob name or context where this should be
+applied.
-@refcommands
-
-The following commands set @code{fontSize} for the current voice:
-
-@cindex @code{\tiny}
-@code{\tiny},
-@cindex @code{\small}
-@code{\small},
-@cindex @code{\normalsize}
-@code{\normalsize}.
-
-
-
-@cindex magnification
-@cindex cue notes
-
-
-@node Font selection
-@subsection Font selection
-
-Font selection for the standard fonts, @TeX{}'s Computer Modern fonts,
-can also be adjusted with a more fine-grained mechanism. By setting
-the object properties described below, you can select a different font;
-all three mechanisms work for every object that supports
-@code{font-interface}:
-
-
-@itemize @bullet
-@item @code{font-encoding}
-is a symbol that sets layout of the glyphs. Choices include
-@code{text} for normal text, @code{braces} (for piano staff braces),
-@code{music} (the standard music font, including ancient glyphs),
-@code{dynamic} (for dynamic signs) and @code{number} for the number
-font.
-
-
-@item @code{font-family}
- is a symbol indicating the general class of the typeface. Supported are
-@code{roman} (Computer Modern), @code{sans}, and @code{typewriter}.
-
-@item @code{font-shape}
- is a symbol indicating the shape of the font, there are typically
-several font shapes available for each font family. Choices are
-@code{italic}, @code{caps}, and @code{upright}.
-
-@item @code{font-series}
-is a symbol indicating the series of the font. There are typically several
-font series for each font family and shape. Choices are @code{medium}
-and @code{bold}.
+This technique only works for objects that are directly connected to
+an @internalsref{Event} from the input, for example
+@itemize
+@item note heads, caused by chord-pitch (i.e., notes inside a chord)
+@item articulation signs, caused by articulation instructions
@end itemize
-Fonts selected in the way sketched above come from a predefined style
-sheet.
-
- The font used for printing a object can be selected by setting
-@code{font-name}, e.g.
-@example
- \override Staff.TimeSignature
- #'font-name = #"cmr17"
-@end example
-
-@noindent
-Any font can be used, as long as it is available to @TeX{}. Possible
-fonts include foreign fonts or fonts that do not belong to the
-Computer Modern font family. The size of fonts selected in this way
-can be changed with the @code{font-magnification} property. For
-example, @code{2.0} blows up all letters by a factor 2 in both
-directions.
+It notably does not work for stems and accidentals (these are caused
+by note heads, not by music events) or clefs (these are not caused by
+music inputs, but rather by the change of a property value).
-@cindex font size
-@cindex font magnification
+There are very few objects which are @emph{directly} connected to
+output. A normal note (like @code{c4}) is not directly connected
+to output, so
-
-
-@seealso
-
-Init files: @file{ly/declarations-init.ly} contains hints how new
-fonts may be added to LilyPond.
-
-@refbugs
-
-No style sheet is provided for other fonts besides the @TeX{}
-Computer Modern family.
-
-@cindex font selection
-@cindex font magnification
-@cindex @code{font-interface}
-
-
-@node Text markup
-@section Text markup
-@cindex text markup
-@cindex markup text
-
-
-@cindex typeset text
-
-LilyPond has an internal mechanism to typeset texts. You can access it
-with the keyword @code{\markup}. Within markup mode, you can enter texts
-similar to lyrics: simply enter them, surrounded by spaces:
-@cindex markup
-
-@lilypond[verbatim,fragment,relative=1]
- c1^\markup { hello }
- c1_\markup { hi there }
- c1^\markup { hi \bold there, is \italic anyone home? }
-@end lilypond
-
-@cindex font switching
-
-The markup in the example demonstrates font switching commands. The
-command @code{\bold} and @code{\italic} apply to the first following
-word only; enclose a set of texts with braces to apply a command
-to more words:
@example
- \markup @{ \bold @{ hi there @} @}
+\tweak #'color #red c4
@end example
@noindent
-For clarity, you can also do this for single arguments, e.g.
-
-@verbatim
- \markup { is \italic { anyone } home }
-@end verbatim
-
-@cindex font size, texts
-
-
-In markup mode you can compose expressions, similar to mathematical
-expressions, XML documents, and music expressions. The braces group
-notes into horizontal lines. Other types of lists also exist: you can
-stack expressions grouped with @code{<} and @code{>} vertically with
-the command @code{\column}. Similarly, @code{\center-align} aligns
-texts by their center lines:
-
-@lilypond[verbatim,fragment,relative=1]
- c1^\markup { \column < a bbbb c > }
- c1^\markup { \center-align < a bbbb c > }
- c1^\markup { \line < a b c > }
-@end lilypond
+does not change color. See @ref{Displaying music expressions}, for
+details.
-Markups can be stored in variables, and these variables
-may be attached to notes, like
-@verbatim
-allegro = \markup { \bold \large { Allegro } }
-\notes { a^\allegro b c d }
-@end verbatim
+@node Using Scheme code instead of \tweak
+@subsection Using Scheme code instead of @code{\tweak}
+The main disadvantage of @code{\tweak} is its syntactical
+inflexibility. For example, the following produces a syntax error.
-Some objects have alignment procedures of their own, which cancel out
-any effects of alignments applied to their markup arguments as a
-whole. For example, the @internalsref{RehearsalMark} is horizontally
-centered, so using @code{\mark \markup @{ \left-align .. @}} has no
-effect.
-
-Similarly, for moving whole texts over notes with
-@code{\raise}, use the following trick:
@example
- "" \raise #0.5 raised
-@end example
-
-The text @code{raised} is now raised relative to the empty string
-@code{""} which is not visible. Alternatively, complete objects can
-be moved with layout properties such as @code{padding} and
-@code{extra-offset}.
-
-
-
-@seealso
-
-Init files: @file{scm/new-markup.scm}.
-
-
-@refbugs
+F = \tweak #'font-size #-3 -\flageolet
-Text layout is ultimately done by @TeX{}, which does kerning of
-letters. LilyPond does not account for kerning, so texts will be
-spaced slightly too wide.
-
-Syntax errors for markup mode are confusing.
-
-Markup texts cannot be used in the titling of the @code{\header}
-field. Titles are made by La@TeX{}, so La@TeX{} commands should be used
-for formatting.
-
-
-
-@menu
-* Overview of text markup commands::
-@end menu
-
-@node Overview of text markup commands
-@subsection Overview of text markup commands
-
-@include markup-commands.tely
-
-
-@node Global layout
-@section Global layout
-
-The global layout determined by three factors: the page layout, the
-line breaks, and the spacing. These all influence each other. The
-choice of spacing determines how densely each system of music is set,
-which influences where line breaks are chosen, and thus
-ultimately how many pages a piece of music takes. This section
-explains how to tune the algorithm for spacing.
-
-Globally spoken, this procedure happens in three steps: first,
-flexible distances (``springs'') are chosen, based on durations. All
-possible line breaking combination are tried, and the one with the
-best results --- a layout that has uniform density and requires as
-little stretching or cramping as possible --- is chosen.
-
-After spacing and linebreaking, the systems are distributed across
-pages, taking into account the size of the page, and the size of the
-titles.
-
-
-
-@menu
-* Setting global staff size::
-* Vertical spacing::
-* Horizontal spacing::
-* Line breaking::
-* Line length and line breaking::
-* Titling::
-* Page breaking::
-* Paper size::
-* Page layout::
-@end menu
-
-
-@node Setting global staff size
-@subsection Setting global staff size
-
-@cindex font size, setting
-@cindex staff size, setting
-@cindex @code{paper} file
-
-The Feta font provides musical symbols at eight different
-sizes. Each font is tuned for a different staff size: at a smaller size
-the font becomes heavier, to match the relatively heavier staff lines.
-The recommended font sizes are listed in the following table:
-
-@multitable @columnfractions .25 .25 .25 .25
-
-@item @b{font name}
-@tab @b{staff height (pt)}
-@tab @b{staff height (mm)}
-@tab @b{use}
-
-@item feta11
-@tab 11.22
-@tab 3.9
-@tab pocket scores
-
-@item feta13
-@tab 12.60
-@tab 4.4
-@tab
-
-@item feta14
-@tab 14.14
-@tab 5.0
-@tab
-
-@item feta16
-@tab 15.87
-@tab 5.6
-@tab
-
-@item feta18
-@tab 17.82
-@tab 6.3
-@tab song books
-
-@item feta20
-@tab 17.82
-@tab 7.0
-@tab standard parts
-
-@item feta23
-@tab 22.45
-@tab 7.9
-@tab
-
-@item feta26
-@tab 25.2
-@tab 8.9
-@tab
-@c modern rental material ?
-
-@end multitable
-
-These fonts are available in any sizes. The context property
-@code{fontSize} and the layout property @code{staff-space} (in
-@internalsref{StaffSymbol}) can be used to tune size for individual
-staves. The size of individual staves are relative to the global size,
-which can be set in the following manner:
-
-@example
- #(set-global-staff-size 14)
+\relative c'' @{
+ c4^\F c4_\F
+@}
@end example
-This sets the global default size to 14pt staff height, and scales all
-fonts accordingly.
-
-@seealso
-
-This manual: @ref{Selecting font sizes}.
-
-
+@noindent
+With other words, @code{\tweak} doesn't behave like an articulation
+regarding the syntax; in particular, it can't be attached with
+@code{^} and @code{_}.
-@menu
-* Vertical spacing::
-* Horizontal spacing::
-* Line breaking::
-* Page layout::
-@end menu
+Using Scheme, this problem can be circumvented. The route to the
+result is given in @ref{Adding articulation to notes (example)},
+especially how to use @code{\displayMusic} as a helping guide.
-@node Vertical spacing
-@subsection Vertical spacing
-
-@cindex vertical spacing
-@cindex distance between staves
-@cindex staff distance
-@cindex between staves, distance
-@cindex staves per page
-@cindex space between staves
-
-The height of each system is determined automatically by LilyPond, to
-keep systems from bumping into each other, some minimum distances are
-set. By changing these, you can put staves closer together, and thus
-put more systems onto one page.
-
-Normally staves are stacked vertically. To make
-staves maintain a distance, their vertical size is padded. This is
-done with the property @code{minimumVerticalExtent}. It takes a pair
-of numbers, so if you want to make it smaller from its, then you could
-set
@example
- \set Staff.minimumVerticalExtent = #'(-4 . 4)
-@end example
-This sets the vertical size of the current staff to 4 staff spaces on
-either side of the center staff line. The argument of
-@code{minimumVerticalExtent} is interpreted as an interval, where the
-center line is the 0, so the first number is generally negative. The
-staff can be made larger at the bottom by setting it to @code{(-6
-. 4)}.
-
-The piano staves are handled a little differently: to make cross-staff
-beaming work correctly, it is necessary that the distance between staves
-is fixed beforehand. This is also done with a
-@internalsref{VerticalAlignment} object, created in
-@internalsref{PianoStaff}. In this object the distance between the
-staves is fixed by setting @code{forced-distance}. If you want to
-override this, use a @code{\context} block as follows:
-@example
- \paper @{
- \context @{
- \PianoStaff
- \override VerticalAlignment #'forced-distance = #9
- @}
- @dots{}
- @}
+F = #(let ((m (make-music 'ArticulationEvent
+ 'articulation-type "flageolet")))
+ (set! (ly:music-property m 'tweaks)
+ (acons 'font-size -3
+ (ly:music-property m 'tweaks)))
+ m)
+
+\relative c'' @{
+ c4^\F c4_\F
+@}
@end example
-This would bring the staves together at a distance of 9 staff spaces,
-measured from the center line of each staff.
-
-@seealso
-
-Internals: Vertical alignment of staves is handled by the
-@internalsref{VerticalAlignment} object.
-
-
-
-
-@node Horizontal spacing
-@subsection Horizontal Spacing
-The spacing engine translates differences in durations into
-stretchable distances (``springs'') of differing lengths. Longer
-durations get more space, shorter durations get less. The shortest
-durations get a fixed amount of space (which is controlled by
-@code{shortest-duration-space} in the @internalsref{SpacingSpanner} object).
-The longer the duration, the more space it gets: doubling a
-duration adds a fixed amount (this amount is controlled by
-@code{spacing-increment}) of space to the note.
-
-For example, the following piece contains lots of half, quarter, and
-8th notes, the eighth note is followed by 1 note head width (NHW).
-The quarter note is followed by 2 NHW, the half by 3 NHW, etc.
-@lilypond[fragment,verbatim,relative=1] c2 c4. c8 c4. c8 c4. c8 c8
-c8 c4 c4 c4
-@end lilypond
-
-Normally, @code{shortest-duration-space} is set to 1.2, which is the
-width of a note head, and @code{shortest-duration-space} is set to
-2.0, meaning that the shortest note gets 2 NHW (i.e. 2 times
-@code{shortest-duration-space}) of space. For normal notes, this space
-is always counted from the left edge of the symbol, so the shortest
-notes are generally followed by one NHW of space.
-
-If one would follow the above procedure exactly, then adding a single
-32th note to a score that uses 8th and 16th notes, would widen up the
-entire score a lot. The shortest note is no longer a 16th, but a 32nd,
-thus adding 1 NHW to every note. To prevent this, the
-shortest duration for spacing is not the shortest note in the score,
-but the most commonly found shortest note. Notes that are even
-shorter this are followed by a space that is proportional to their
-duration relative to the common shortest note. So if we were to add
-only a few 16th notes to the example above, they would be followed by
-half a NHW:
-
-@lilypond[fragment,verbatim,relative=2]
- c2 c4. c8 c4. c16[ c] c4. c8 c8 c8 c4 c4 c4
-@end lilypond
-
-The most common shortest duration is determined as follows: in every
-measure, the shortest duration is determined. The most common short
-duration, is taken as the basis for the spacing, with the stipulation
-that this shortest duration should always be equal to or shorter than
-1/8th note. The shortest duration is printed when you run lilypond
-with @code{--verbose}. These durations may also be customized. If you
-set the @code{common-shortest-duration} in
-@internalsref{SpacingSpanner}, then this sets the base duration for
-spacing. The maximum duration for this base (normally 1/8th), is set
-through @code{base-shortest-duration}.
-
-@cindex @code{common-shortest-duration}
-@cindex @code{base-shortest-duration}
-@cindex @code{stem-spacing-correction}
-@cindex @code{spacing}
-
-In the Introduction it was explained that stem directions influence
-spacing. This is controlled with @code{stem-spacing-correction}
-property in @internalsref{NoteSpacing}, which are generated for every
-@internalsref{Voice} context. The @code{StaffSpacing} object
-(generated at @internalsref{Staff} context) contains the same property
-for controlling the stem/bar line spacing. The following example
-shows these corrections, once with default settings, and once with
-exaggerated corrections:
-
-@lilypond
- \score { \notes {
- c'4 e''4 e'4 b'4 |
- b'4 e''4 b'4 e''4|
- \override Staff.NoteSpacing #'stem-spacing-correction = #1.5
- \override Staff.StaffSpacing #'stem-spacing-correction = #1.5
- c'4 e''4 e'4 b'4 |
- b'4 e''4 b'4 e''4|
- }
- \paper { raggedright = ##t } }
-@end lilypond
-
-@cindex SpacingSpanner, overriding properties
+@noindent
+Here, the @code{tweaks} properties of the flageolet object
+@code{m} (created with @code{make-music}) are extracted with
+@code{ly:music-property}, a new key-value pair to change the
+font size is prepended to the property list with the
+@code{acons} Scheme function, and the result is finally
+written back with @code{set!}. The last element of the
+@code{let} block is the return value, @code{m} itself.
+
+
+@node \set versus \override
+@subsection @code{\set} vs. @code{\override}
+
+We have seen two methods of changing properties: @code{\set} and
+@code{\override}. There are actually two different kinds of
+properties.
+
+Contexts can have properties, which are usually named in
+@code{studlyCaps}. They mostly control the translation from
+music to notatino, eg. @code{localKeySignature} (for determining
+whether to print accidentals), @code{measurePosition} (for
+determining when to print a bar line). Context properties can
+change value over time while interpreting a piece of music;
+@code{measurePosition} is an obvious example of
+this. Context properties are modified with @code{\set}.
+
+There is a special type of context property: the element
+description. These properties are named in @code{StudlyCaps}
+(starting with capital letters). They contain the
+@q{default settings} for said graphical object as an
+association list. See @file{scm/@/define@/-grobs@/.scm}
+to see what kind of settings there are. Element descriptions
+may be modified with @code{\override}.
+
+@code{\override} is actually a shorthand;
-Properties of the @internalsref{SpacingSpanner} must be overridden
-from the @code{\paper} block, since the @internalsref{SpacingSpanner} is
-created before any property commands are interpreted.
@example
-\paper @{ \context @{
- \Score
- \override SpacingSpanner #'spacing-increment = #3.0
-@} @}
+\override @var{context}.@var{name} #'@var{property} = #@var{value}
@end example
+@noindent
+is more or less equivalent to
-@seealso
-
-Internals: @internalsref{SpacingSpanner}, @internalsref{NoteSpacing},
-@internalsref{StaffSpacing}, @internalsref{SeparationItem}, and
-@internalsref{SeparatingGroupSpanner}.
-
-@refbugs
-
-Spacing is determined on a score wide basis. If you have a score that
-changes its character (measured in durations) halfway during the
-score, the part containing the longer durations will be spaced too
-widely.
-
-There is no convenient mechanism to manually override spacing. The
-following work-around may be used to insert extra space into a score.
+@c leave this long line -gp
@example
- \once \override Score.SeparationItem #'padding = #1
+\set @var{context}.@var{name} #'@var{property} = #(cons (cons '@var{property} @var{value}) <previous value of @var{context})
@end example
-No work-around exists for decreasing the amount of space.
-
-
-@menu
-* Line breaking::
-* Page layout::
-@end menu
+The value of @code{context} (the alist) is used to initalize
+the properties of individual grobs. Grobs also have
+properties, named in Scheme style, with
+@code{dashed-words}. The values of grob properties change
+during the formatting process: formatting basically amounts
+to computing properties using callback functions.
-@node Line breaking
-@subsection Line breaking
+@code{fontSize} is a special property: it is equivalent to
+entering @code{\override ... #'font-size} for all pertinent
+objects. Since this is a common change, the special
+property (modified with @code{\set}) was created.
-@cindex line breaks
-@cindex breaking lines
-Line breaks are normally computed automatically. They are chosen such
-that lines look neither cramped nor loose, and that consecutive lines
-have similar density.
+@node Difficult tweaks
+@subsection Difficult tweaks
-Occasionally you might want to override the automatic breaks; you can
-do this by specifying @code{\break}. This will force a line break at
-this point. Line breaks can only occur at places where there are bar
-lines. If you want to have a line break where there is no bar line,
-you can force an invisible bar line by entering @code{\bar
-""}. Similarly, @code{\noBreak} forbids a line break at a
-point.
+There are a few classes of difficult adjustments.
+@itemize
-@cindex regular line breaks
-@cindex four bar music.
-
-For line breaks at regular intervals use @code{\break} separated by
-skips and repeated with @code{\repeat}:
-@example
-<< \repeat unfold 7 @{
- s1 \noBreak s1 \noBreak
- s1 \noBreak s1 \break @}
- @emph{the real music}
->>
-@end example
-
-@noindent
-This makes the following 28 measures (assuming 4/4 time) be broken every
-4 measures, and only there.
-
-@refcommands
-
-@code{\break}, and @code{\noBreak}.
-@cindex @code{\break}
-@cindex @code{\noBreak}
-
-@seealso
-
-Internals: @internalsref{BreakEvent}.
-
-@node Line length and line breaking
-@subsection Line length and line breaking
-@cindex page breaks
-@cindex breaking pages
+@item
+One type of difficult adjustment is the appearance of spanner objects,
+such as slur and tie. Initially, only one of these objects is created,
+and they can be adjusted with the normal mechanism. However, in some
+cases the spanners cross line breaks. If this happens, these objects
+are cloned. A separate object is created for every system that it is
+in. These are clones of the original object and inherit all
+properties, including @code{\override}s.
-@cindex @code{indent}
-@cindex @code{linewidth}
-The most basic settings influencing the spacing are @code{indent} and
-@code{linewidth}. They are set in the @code{\paper} block. They
-control the indentation of the first line of music, and the lengths of
-the lines.
+In other words, an @code{\override} always affects all pieces of a
+broken spanner. To change only one part of a spanner at a line break,
+it is necessary to hook into the formatting process. The
+@code{after-line-breaking} callback contains the Scheme procedure that
+is called after the line breaks have been determined, and layout
+objects have been split over different systems.
-If @code{raggedright} is set to true in the @code{\paper}
-block, then the lines are justified at their natural length. This
-useful for short fragments, and for checking how tight the natural
-spacing is.
+In the following example, we define a procedure
+@code{my-callback}. This procedure
-@cindex page layout
-@cindex vertical spacing
+@itemize
+@item
+determines if we have been split across line breaks
+@item
+if yes, retrieves all the split objects
+@item
+checks if we are the last of the split objects
+@item
+if yes, it sets @code{extra-offset}.
+@end itemize
-The option @code{raggedlast} is similar to @code{raggedright}, but
-only affects the last line of the piece. No restrictions are put on
-that line. The result is similar to formatting paragraphs. In a
-paragraph, the last line simply takes its natural length.
+This procedure is installed into @internalsref{Tie}, so the last part
+of the broken tie is translated up.
+@lilypond[quote,verbatim,ragged-right]
+#(define (my-callback grob)
+ (let* (
+ ; have we been split?
+ (orig (ly:grob-original grob))
-@node Titling
-@subsection Titling
+ ; if yes, get the split pieces (our siblings)
+ (siblings (if (ly:grob? orig)
+ (ly:spanner-broken-into orig) '() )))
-Titles are created for each @code{\score} block, and over a
-@code{\book}.
+ (if (and (>= (length siblings) 2)
+ (eq? (car (last-pair siblings)) grob))
+ (ly:grob-set-property! grob 'extra-offset '(-2 . 5)))))
-The contents of the titles are taken from the @code{\header} blocks.
-The header block for a book supports the following
-@table @code
-@item title
- The title of the music. Centered on top of the first page.
-@item subtitle
- Subtitle, centered below the title.
-@item poet
- Name of the poet, left flushed below the subtitle.
-@item composer
- Name of the composer, right flushed below the subtitle.
-@item meter
- Meter string, left flushed below the poet.
-@item opus
- Name of the opus, right flushed below the composer.
-@item arranger
- Name of the arranger, right flushed below the opus.
-@item instrument
- Name of the instrument, centered below the arranger.
-@item dedication
- To whom the piece is dedicated.
-@item piece
- Name of the piece, left flushed below the instrument.
-@end table
-
-This is a demonstration of the fields available,
-
-@lilypond[verbatim]
-\book {
- \header {
- title = "Title"
- subtitle = "(and (the) subtitle)"
- subsubtitle = "Sub sub title"
- poet = "Poet"
- composer = "Composer"
- texttranslator = "Text Translator"
- meter = "Meter"
- arranger = "Arranger"
- instrument = "Instrument"
- piece = "Piece"
- }
-
- \score {
- \header {
- piece = "piece1"
- opus = "opus1"
- }
- { c'1 }
- }
- \score {
- \header {
- piece = "piece2"
- opus = "opus2"
- }
- { c'1 }
- }
+\relative c'' {
+ \override Tie #'after-line-breaking =
+ #my-callback
+ c1 ~ \break c2 ~ c
}
@end lilypond
-Different fonts may be selected for each element, by using a
-@code{\markup}, e.g.
-
-@verbatim
- \header {
- title = \markup { \italic { The italic title } }
- }
-@end verbatim
-
-A more advanced option is to change the Scheme functions
-@code{make-book-title} and @code{make-score-title} functions, defined
-in the @code{\bookpaper} of the @code{\book} block. These functions
-create a block of titling, given the information in the
-@code{\header}. The init file @file{ly/titling.scm} shows how the
-default format is created, and it may be used as a template for
-different styles.
-
-
-@cindex \bookpaper
-@cindex header
-@cindex footer
-@cindex page layout
-@cindex titles
-
-
-
-
-@node Page breaking
-@subsection Page breaking
-
-The default page breaking may be overriden by inserting
-@code{\pageBreak} or @code{\noPageBreak} commands. These commands are
-analogous to @code{\break} and @code{\noBreak}. They should be
-inserted with a bar line. These commands force and forbid a page-break
-from happening.
-
-Page breaks are computed by the @code{page-breaking} function in the
-@code{\bookpaper} block.
-
-@refcommands
-
-@cindex @code{\pageBreak}
-@code{\pageBreak}
-@cindex @code{\noPageBreak}
-@code{\noPageBreak}
-
-@node Paper size
-@subsection Paper size
-
-@cindex paper size
-@cindex page size
-@cindex @code{papersize}
-
-To change the paper size, there are two commands,
-@example
- #(set-default-paper-size "a4")
- \paper@{
- #(set-paper-size "a4")
- @}
-@end example
-The second one sets the size of the @code{\paper} block that it is in.
-
-
-@node Page layout
-@subsection Page layout
-
-@cindex page layout
-@cindex margins
-@cindex header, page
-@cindex footer, page
-
-LilyPond will do page layout, setting margins and adding headers and
-footers to each page.
+@noindent
+When applying this trick, the new @code{after-line-breaking} callback
+should also call the old one @code{after-line-breaking}, if there is
+one. For example, if using this with @code{Hairpin},
+@code{ly:hairpin::after-line-breaking} should also be called.
-The default layout responds to the following settings in the
-@code{\bookpaper} block
-@cindex \bookpaper
-@table @code
-@item hsize
- The width of the page
-@item vsize
- The height of the page
-@item topmargin (top-margin)
- Margin between header and top of the page
-@item bottommargin (bottom-margin)
- Margin between footer and bottom of the page
-@item headsep (head-sep)
- Distance between top-most music system and the page header
-@item footsep (foot-sep)
- Distance between bottom-most music system and the page footer
-@item raggedbottom
- If set to true, systems will not be spread across the page.
-@item raggedlastbottom
- If set to true, systems will not be spread to fill the last page.
-@end table
+@item Some objects cannot be changed with @code{\override} for
+technical reasons. Examples of those are @code{NonMusicalPaperColumn}
+and @code{PaperColumn}. They can be changed with the
+@code{\overrideProperty} function, which works similar to @code{\once
+\override}, but uses a different syntax.
@example
- \bookpaper@{
- hsize = 2\cm
- topmargin = 3\cm
- bottommargin = 3\cm
- raggedlastbottom = ##t
- @}
+\overrideProperty
+#"Score.NonMusicalPaperColumn" % Grob name
+#'line-break-system-details % Property name
+#'((next-padding . 20)) % Value
@end example
-You can also define these values in scheme. Please note that the scheme
-expressions may have a dash, like @code{foot-sep}, but not LilyPond
-expressions, like @code{footsep}.
-
-@example
- \bookpaper@{
- #(define bottom-margin (* 2 cm))
- @}
-@end example
-
-@c is this explanations really necessary?
-In that case @code{mm}, @code{in}, @code{pt} and @code{cm} are variables
-defined in @file{book-paper-defaults.ly} with values in
-millimeters. That's why the value has to be multiplied in the example
-above.
-
-The default page header puts the page number and the @code{instrument}
-field from the @code{\header} block on a line.
-
-
-
-
-@cindex copyright
-@cindex tagline
-
-The default footer is empty, except for the first page, where it the
-@code{copyright} field from @code{\header} is inserted, and the last
-page, where @code{tagline} from @code{\header} is added. The default
-tagline is ``Engraved by LilyPond (@var{version})''.
-
-The header and footer are created by the functions @code{make-footer}
-and @code{make-header}, defined in @code{\bookpaper}. The default
-implementations are in @file{scm/page-layout.scm}.
-
-The following settings influence the header and footer layout.
-
-@table @code
-@item printpagenumber
- this boolean controls whether a pagenumber is printed.
-@end table
-
-
-
-The page layout itself is done by two functions:
-@code{page-music-height} and @code{page-make-stencil}. The former
-tells the line-breaking algorithm how much space can be spent on a
-page, the latter creates the actual page given the system to put on it.
-
-
-@seealso
-
-Examples: @inputfileref{input/test/,page-breaks.ly}
-
-
+Note, however, that @code{\override}, applied to
+@code{NoteMusicalPaperColumn} and @code{PaperColumn}, still works as
+expected within @code{\context} blocks.
+@end itemize
projects / lilypond.git / blobdiff