1 @c -*- coding: utf-8; mode: texinfo; -*-
2 @c This file is part of lilypond.tely
4 Translation of GIT committish: FILL-IN-HEAD-COMMITTISH
6 When revising a translation, copy the HEAD committish of the
7 version that you are working on. See TRANSLATION for details.
12 @node Changing defaults
13 @chapter Changing defaults
15 @strong{N.B. This Chapter is under heavy development at present.}
17 The purpose of LilyPond's design is to provide the finest output
18 quality as a default. Nevertheless, it may happen that you need to
19 change this default layout. The layout is controlled through a large
20 number of proverbial @q{knobs and switches.} This chapter does not
21 list each and every knob. Rather, it outlines what groups of controls
22 are available and explains how to lookup which knob to use for a
26 @cindex Internals Reference
28 The controls available for tuning are described in a separate
31 Internals Reference manual.
34 @ref{Top,Internals Reference,,lilypond-internals}.
37 lists all different variables, functions and options available in
38 LilyPond. It is written as a HTML document, which is available
39 @c leave the @uref as one long line.
40 @uref{http://@/lilypond@/.org/@/doc/@/stable/@/Documentation/@/user/@/lilypond@/-internals/,on@/-line},
41 but is also included with the LilyPond documentation package.
43 There are four areas where the default settings may be changed:
47 Automatic notation: changing the automatic creation of notation
48 elements. For example, changing the beaming rules.
51 Output: changing the appearance of individual
52 objects. For example, changing stem directions or the location of
56 Context: changing aspects of the translation from music events to
57 notation. For example, giving each staff a separate time signature.
60 Page layout: changing the appearance of the spacing, line
61 breaks, and page dimensions. These modifications are discussed
62 @c in @ref{notation}, and @ref{Spacing issues}.
65 Internally, LilyPond uses Scheme (a LISP dialect) to provide
66 infrastructure. Overriding layout decisions in effect accesses the
67 program internals, which requires Scheme input. Scheme elements are
68 introduced in a @code{.ly} file with the hash mark
69 @code{#}.@footnote{@rlearning{Scheme tutorial}, contains a short tutorial
70 on entering numbers, lists, strings, and symbols in Scheme.}
74 * Interpretation contexts::
75 * Explaining the Internals Reference::
76 * Modifying properties::
77 * Useful concepts and properties::
80 * Discussion of specific tweaks::
84 @node Interpretation contexts
85 @section Interpretation contexts
87 This section describes what contexts are, and how to modify them.
90 * Contexts explained::
92 * Modifying context plug-ins::
93 * Changing context default settings::
94 * Defining new contexts::
99 @node Contexts explained
100 @subsection Contexts explained
103 @c TODO Rethink and rewrite
105 >> > > - list of contexts: my *danger unmaintainable*
106 >> > > alarm just went off. I'm
108 I knew it would... And leaving out some of them is perfectly fine
110 I do think that a list like this, with the main contexts and a
112 description of what they do (perhaps also with a note about what
114 behavior is associated with each of them, but this may be
116 should be there, and then we could simply list the remaining ones
118 further explanation and with links to the IR.
121 @c TODO Improve layout, order and consistency of wording -td
123 @c TODO Add introduction which explains contexts in generality -td
125 Contexts are arranged heirarchically:
128 * Score - the master of all contexts::
129 * Top-level contexts - staff containers::
130 * Intermediate-level contexts - staves::
131 * Bottom-level contexts - voices::
134 @node Score - the master of all contexts
135 @unnumberedsubsubsec Score - the master of all contexts
137 This is the top level notation context. No other context can
138 contain a Score context. By default the Score context handles
139 the administration of time signatures and makes sure that items
140 such as clefs, time signatures, and key-signatures are aligned
143 A Score context is instantiated implicitly when a
144 @code{\score @{@dots{}@}} or @code{\layout @{@dots{}@}} block is
145 processed, or explicitly when a @code{\new Score} command is
148 @node Top-level contexts - staff containers
149 @unnumberedsubsubsec Top-level contexts - staff containers
151 @strong{@emph{StaffGroup}}
153 Groups staves while adding a bracket on the left side, grouping
154 the staves together. The bar lines of the contained staves are
155 connected vertically. StaffGroup only consists of a collection
156 of staves, with a bracket in front and spanning bar lines.
158 @strong{@emph{ChoirStaff}}
160 Identical to StaffGroup except that the bar lines of the contained
161 staves are not connected vertically.
163 @strong{@emph{GrandStaff}}
165 A group of staves, with a brace on the left side, grouping
166 the staves together. The bar lines of the contained staves are
167 connected vertically.
169 @strong{@emph{PianoStaff}}
171 TODO No longer correct? Check. -td
173 Just like GrandStaff but with a forced distance between the
174 staves, so cross staff beaming and slurring can be used.
176 @strong{@emph{InnerStaffGroup}}
180 @strong{@emph{InnerChoirStaff}}
184 @node Intermediate-level contexts - staves
185 @unnumberedsubsubsec Intermediate-level contexts - staves
187 @strong{@emph{Staff}}
189 Handles clefs, bar lines, keys, accidentals. It can contain
192 @strong{@emph{RhythmicStaff}}
194 Like Staff but for printing rhythms. Pitches are ignored;
195 the notes are printed on one line.
197 @strong{@emph{TabStaff}}
199 Context for generating tablature. By default lays the music
200 expression out as a guitar tablature, printed on six lines.
202 @strong{@emph{DrumStaff}}
204 Handles typesetting for percussion. Can contain DrumVoice
206 @strong{@emph{VaticanaStaff}}
208 Same as Staff, except that it is designed for typesetting
209 a piece in gregorian style.
211 @strong{@emph{MensuralStaff}}
213 Same as Staff, except that it is designed for typesetting
214 a piece in mensural style.
216 @node Bottom-level contexts - voices
217 @unnumberedsubsubsec Bottom-level contexts - voices
219 Voice-level contexts initialise certain properties and start
220 appropriate engravers. Being bottom-level contexts, they cannot
221 contain other contexts.
223 @strong{@emph{Voice}}
225 Corresponds to a voice on a staff. This context handles the
226 conversion of dynamic signs, stems, beams, super- and sub-scripts,
227 slurs, ties, and rests. You have to instantiate this explicitly
228 if you require multiple voices on the same staff.
230 @strong{@emph{VaticanaVoice}}
232 Same as Voice, except that it is designed for typesetting a piece
235 @strong{@emph{MensuralVoice}}
237 Same as Voice, with modifications for typesetting a piece in
240 @strong{@emph{Lyrics}}
242 Corresponds to a voice with lyrics. Handles the printing of a
243 single line of lyrics.
245 @strong{@emph{DrumVoice}}
247 The voice context used in a percussion staff.
249 @strong{@emph{FiguredBass}}
251 The context in which BassFigure objects are created from
252 input entered in @code{\figuremode} mode.
254 @strong{@emph{TabVoice}}
256 The voice context used within a TabStaff context. Usually left to
257 be created implicitly.
259 @strong{@emph{ChordNames}}
261 Typesets chord names.
263 ------------------------------
267 Then the following, which I don't know what to do with:
269 * GregorianTranscriptionVoice
270 * GregorianTranscriptionStaff
273 Engraves fretboards from chords. Not easy... Not
275 There is now some documentation on FretBoards in the NR, under
276 instrument-specific notation -- cds.
280 * CueVoice Not documented
282 Hard coded entry point for LilyPond. Cannot be tuned.
284 Silently discards all musical information given to this
288 @node Creating contexts
289 @subsection Creating contexts
291 @c TODO \new Score and \score
292 @c TODO more complete descriptions rather than learning style
294 For scores with only one voice and one staff, contexts are
295 created automatically. For more complex scores, it is necessary to
296 create them by hand. There are three commands that do this.
301 The easiest command is @code{\new}, and it also the quickest to type.
302 It is prepended to a music expression, for example
306 @cindex Context, creating
309 \new @var{type} @var{music expression}
313 where @var{type} is a context name (like @code{Staff} or
314 @code{Voice}). This command creates a new context, and starts
315 interpreting the @var{music expression} with that.
317 A practical application of @code{\new} is a score with many
318 staves. Each part that should be on its own staff, is preceded with
321 @lilypond[quote,verbatim,relative=2,ragged-right,fragment]
328 The @code{\new} command may also give a name to the context,
331 \new @var{type} = @var{id} @var{music}
333 However, this user specified name is only used if there is no other
334 context already earlier with the same name.
340 Like @code{\new}, the @code{\context} command also directs a music
341 expression to a context object, but gives the context an explicit name. The
345 \context @var{type} = @var{id} @var{music}
348 This form will search for an existing context of type @var{type}
349 called @var{id}. If that context does not exist yet, a new
350 context with the specified name is created. This is useful if
351 the context is referred to later on. For example, when
352 setting lyrics the melody is in a named context
355 \context Voice = "@b{tenor}" @var{music}
359 so the texts can be properly aligned to its notes,
362 \new Lyrics \lyricsto "@b{tenor}" @var{lyrics}
367 Another possible use of named contexts is funneling two different
368 music expressions into one context. In the following example,
369 articulations and notes are entered separately,
373 arts = @{ s4-. s4-> @}
376 They are combined by sending both to the same @code{Voice} context,
380 \new Staff \context Voice = "A" \music
381 \context Voice = "A" \arts
384 @lilypond[quote,ragged-right]
388 \new Staff \context Voice = "A" \music
389 \context Voice = "A" \arts
393 With this mechanism, it is possible to define an Urtext (original
394 edition), with the option to put several distinct articulations on the
397 @cindex creating contexts
400 The third command for creating contexts is
402 \context @var{type} @var{music}
407 This is similar to @code{\context} with @code{= @var{id}}, but matches
408 any context of type @var{type}, regardless of its given name.
410 This variant is used with music expressions that can be interpreted at
411 several levels. For example, the @code{\applyOutput} command (see
412 @ref{Running a function on all layout objects}). Without an explicit
413 @code{\context}, it is usually applied to @code{Voice}
416 \applyOutput #'@var{context} #@var{function} % apply to Voice
419 To have it interpreted at the @code{Score} or @code{Staff} level use
423 \applyOutput #'Score #@var{function}
424 \applyOutput #'Staff #@var{function}
430 @node Modifying context plug-ins
431 @subsection Modifying context plug-ins
433 @c TODO Should this be Modifying engravers or Modifying contexts?
435 Notation contexts (like @code{Score} and @code{Staff}) not only
437 they also contain plug-ins called @q{engravers} that create notation
438 elements. For example, the @code{Voice} context contains a
439 @code{Note_head_engraver} and the @code{Staff} context contains a
440 @code{Key_signature_engraver}.
442 For a full a description of each plug-in, see
444 @rinternals{Engravers and Performers}.
447 Internals Reference @expansion{} Translation @expansion{} Engravers.
449 Every context described in
451 @rinternals{Contexts}
454 Internals Reference @expansion{} Translation @expansion{} Context.
456 lists the engravers used for that context.
459 It can be useful to shuffle around these plug-ins. This is done by
460 starting a new context with @code{\new} or @code{\context}, and
466 \new @var{context} \with @{
479 where the @dots{} should be the name of an engraver. Here is a simple
480 example which removes @code{Time_signature_engraver} and
481 @code{Clef_engraver} from a @code{Staff} context,
483 @lilypond[quote,relative=1,verbatim,fragment]
489 \remove "Time_signature_engraver"
490 \remove "Clef_engraver"
497 In the second staff there are no time signature or clef symbols. This
498 is a rather crude method of making objects disappear since it will affect
499 the entire staff. This method also influences the spacing, which may or
500 may not be desirable. More sophisticated methods of blanking objects
501 are shown in @rlearning{Visibility and color of objects}.
503 The next example shows a practical application. Bar lines and time
504 signatures are normally synchronized across the score. This is done
505 by the @code{Timing_translator} and @code{Default_bar_line_engraver}.
506 This plug-in keeps an administration of time signature, location
507 within the measure, etc. By moving these engraver from @code{Score} to
508 @code{Staff} context, we can have a score where each staff has its own
511 @cindex polymetric scores
512 @cindex Time signatures, multiple
514 @lilypond[quote,relative=1,ragged-right,verbatim,fragment]
516 \remove "Timing_translator"
517 \remove "Default_bar_line_engraver"
520 \consists "Timing_translator"
521 \consists "Default_bar_line_engraver"
527 \consists "Timing_translator"
528 \consists "Default_bar_line_engraver"
537 @node Changing context default settings
538 @subsection Changing context default settings
540 The adjustments of the previous subsections (
541 @ref{The \set command}, @ref{Modifying context plug-ins}, and
542 @ref{Overview of modifying properties}) can also be entered
543 separately from the music in the @code{\layout} block,
552 \override Stem #'thickness = #4.0
553 \remove "Time_signature_engraver"
558 The @code{\Staff} command brings in the existing definition of the
559 staff context so that it can be modified.
564 \override Stem #'thickness = #4.0
565 \remove "Time_signature_engraver"
569 affect all staves in the score. Other contexts can be modified
572 The @code{\set} keyword is optional within the @code{\layout} block, so
588 It is not possible to collect context changes in a variable and apply
589 them to a @code{\context} definition by referring to that variable.
591 The @code{\RemoveEmptyStaffContext} will overwrite your current
592 @code{\Staff} settings. If you wish to change the defaults for a
593 staff which uses @code{\RemoveEmptyStaffContext}, you must do so
594 after calling @code{\RemoveEmptyStaffContext}, ie
599 \RemoveEmptyStaffContext
601 \override Stem #'thickness = #4.0
606 TODO: add \with in here.
610 @node Defining new contexts
611 @subsection Defining new contexts
613 Specific contexts, like @code{Staff} and @code{Voice}, are made of
614 simple building blocks. It is possible to create new types of
615 contexts with different combinations of engraver plug-ins.
617 The next example shows how to build a different type of
618 @code{Voice} context from scratch. It will be similar to
619 @code{Voice}, but only prints centered slash note heads. It can be used
620 to indicate improvisation in jazz pieces,
622 @lilypond[quote,ragged-right]
625 \type "Engraver_group"
626 \consists "Note_heads_engraver"
627 \consists "Text_engraver"
628 \consists Pitch_squash_engraver
629 squashedPosition = #0
630 \override NoteHead #'style = #'slash
631 \override Stem #'transparent = ##t
635 \accepts "ImproVoice"
639 a4 d8 bes8 \new ImproVoice { c4^"ad lib" c
640 c4 c^"undress" c_"while playing :)" c }
646 These settings are defined within a @code{\context} block inside a
647 @code{\layout} block,
657 In the following discussion, the example input shown should go in place
658 of the @dots{} in the previous fragment.
660 First it is necessary to define a name for the new context:
666 Since it is similar to the @code{Voice}, we want commands that work
667 on (existing) @code{Voice}s to remain working. This is achieved by
668 giving the new context an alias @code{Voice},
674 The context will print notes and instructive texts, so we need to add
675 the engravers which provide this functionality,
678 \consists Note_heads_engraver
679 \consists Text_engraver
682 but we only need this on the center line,
685 \consists Pitch_squash_engraver
686 squashedPosition = #0
689 The @rinternals{Pitch_squash_engraver} modifies note heads (created
690 by @rinternals{Note_heads_engraver}) and sets their vertical
691 position to the value of @code{squashedPosition}, in this case@tie{}@code{0},
694 The notes look like a slash, and have no stem,
697 \override NoteHead #'style = #'slash
698 \override Stem #'transparent = ##t
701 All these plug-ins have to cooperate, and this is achieved with a
702 special plug-in, which must be marked with the keyword @code{\type}.
703 This should always be @rinternals{Engraver_group},
706 \type "Engraver_group"
714 \type "Engraver_group"
715 \consists "Note_heads_engraver"
716 \consists "Text_engraver"
717 \consists Pitch_squash_engraver
718 squashedPosition = #0
719 \override NoteHead #'style = #'slash
720 \override Stem #'transparent = ##t
726 Contexts form hierarchies. We want to hang the @code{ImproVoice}
727 under @code{Staff}, just like normal @code{Voice}s. Therefore, we
728 modify the @code{Staff} definition with the @code{\accepts}
739 The opposite of @code{\accepts} is @code{\denies},
740 which is sometimes needed when reusing existing context definitions.
742 Putting both into a @code{\layout} block, like
752 \accepts "ImproVoice"
757 Then the output at the start of this subsection can be entered as
765 c c_"while playing :)"
772 @node Aligning contexts
773 @subsection Aligning contexts
775 New contexts may be aligned above or below existing contexts. This
776 could be useful in setting up a vocal staff (@rlearning{Vocal ensembles}) and
779 @c TODO Better example needed. Ref LM, and expand on it.
782 @findex alignAboveContext
783 @findex alignBelowContext
785 @lilypond[quote,ragged-right]
788 \relative c' \new Staff = "main" {
791 \new Staff \with {alignAboveContext=main} \ossia
799 @node Explaining the Internals Reference
800 @section Explaining the Internals Reference
804 * Navigating the program reference::
805 * Layout interfaces::
806 * Determining the grob property::
807 * Naming conventions::
810 @node Navigating the program reference
811 @subsection Navigating the program reference
813 @c TODO remove this (it's in the LM)
814 @c Replace with more factual directions
816 Suppose we want to move the fingering indication in the fragment
819 @lilypond[quote,fragment,relative=2,verbatim]
825 If you visit the documentation on fingering instructions (in
826 @ref{Fingering instructions}), you will notice:
831 Internals Reference: @rinternals{Fingering}.
836 @c outdated info; probably will delete.
838 This fragment points to two parts of the program reference: a page
839 on @code{FingerEvent} and one on @code{Fingering}.
841 The page on @code{FingerEvent} describes the properties of the music
842 expression for the input @code{-2}. The page contains many links
843 forward. For example, it says
846 Accepted by: @rinternals{Fingering_engraver},
850 That link brings us to the documentation for the Engraver, the
854 This engraver creates the following layout objects: @rinternals{Fingering}.
857 In other words, once the @code{FingerEvent}s are interpreted, the
858 @code{Fingering_engraver} plug-in will process them.
862 @c I can't figure out what this is supposed to mean. -gp
864 The @code{Fingering_engraver} is also listed to create
865 @rinternals{Fingering} objects,
867 @c old info? it doesn't make any sense to me with our current docs.
869 second bit of information listed under @b{See also} in the Notation
874 The programmer's reference is available as an HTML document. It is
875 highly recommended that you read it in HTML form, either online or
876 by downloading the HTML documentation. This section will be much more
877 difficult to understand if you are using the
881 Follow the link to @rinternals{Fingering}. At the top of the
885 Fingering objects are created by: @rinternals{Fingering_engraver} and
886 @rinternals{New_fingering_engraver}.
889 By following related links inside the program reference, we can follow the
890 flow of information within the program:
894 @item @rinternals{Fingering}:
895 @rinternals{Fingering} objects are created by:
896 @rinternals{Fingering_engraver}
898 @item @rinternals{Fingering_engraver}:
899 Music types accepted: @rinternals{fingering-event}
901 @item @rinternals{fingering-event}:
902 Music event type @code{fingering-event} is in Music expressions named
903 @rinternals{FingerEvent}
906 This path goes against the flow of information in the program: it
907 starts from the output, and ends at the input event. You could
908 also start at an input event, and read with the flow of
909 information, eventually ending up at the output object(s).
911 The program reference can also be browsed like a normal document. It
914 @rinternals{Music definitions},
917 @code{Music definitions}
919 on @rinternals{Translation}, and the @rinternals{Backend}. Every
920 chapter lists all the definitions used and all properties that may be
924 @node Layout interfaces
925 @subsection Layout interfaces
927 @cindex interface, layout
928 @cindex layout interface
931 The HTML page that we found in the previous section describes the
932 layout object called @rinternals{Fingering}. Such an object is a
933 symbol within the score. It has properties that store numbers (like
934 thicknesses and directions), but also pointers to related objects. A
935 layout object is also called a @emph{Grob}, which is short for Graphical
936 Object. For more details about Grobs, see @rinternals{grob-interface}.
938 The page for @code{Fingering} lists the definitions for the
939 @code{Fingering} object. For example, the page says
942 @code{padding} (dimension, in staff space):
948 which means that the number will be kept at a distance of at least 0.5
952 Each layout object may have several functions as a notational or
953 typographical element. For example, the Fingering object
954 has the following aspects
958 Its size is independent of the horizontal spacing, unlike slurs or beams.
961 It is a piece of text. Granted, it is usually a very short text.
964 That piece of text is typeset with a font, unlike slurs or beams.
967 Horizontally, the center of the symbol should be aligned to the
968 center of the note head.
971 Vertically, the symbol is placed next to the note and the staff.
974 The vertical position is also coordinated with other superscript
975 and subscript symbols.
978 Each of these aspects is captured in so-called @emph{interface}s,
979 which are listed on the @rinternals{Fingering} page at the bottom
982 This object supports the following interfaces:
983 @rinternals{item-interface},
984 @rinternals{self-alignment-interface},
985 @rinternals{side-position-interface}, @rinternals{text-interface},
986 @rinternals{text-script-interface}, @rinternals{font-interface},
987 @rinternals{finger-interface}, and @rinternals{grob-interface}.
990 Clicking any of the links will take you to the page of the respective
991 object interface. Each interface has a number of properties. Some of
992 them are not user-serviceable (@q{Internal properties}), but others
995 We have been talking of @emph{the} @code{Fingering} object, but actually it
996 does not amount to much. The initialization file (see
997 @rlearning{Other sources of information})
998 @file{scm/@/define@/-grobs@/.scm} shows the soul of the @q{object},
1003 (avoid-slur . around)
1004 (slur-padding . 0.2)
1005 (staff-padding . 0.5)
1006 (self-alignment-X . 0)
1007 (self-alignment-Y . 0)
1008 (script-priority . 100)
1009 (stencil . ,ly:text-interface::print)
1010 (direction . ,ly:script-interface::calc-direction)
1011 (font-encoding . fetaNumber)
1012 (font-size . -5) ; don't overlap when next to heads.
1013 (meta . ((class . Item)
1014 (interfaces . (finger-interface
1016 text-script-interface
1018 side-position-interface
1019 self-alignment-interface
1020 item-interface))))))
1024 As you can see, the @code{Fingering} object is nothing more than a
1025 bunch of variable settings, and the webpage in the Internals Reference
1026 is directly generated from this definition.
1029 @node Determining the grob property
1030 @subsection Determining the grob property
1032 @c TODO remove this (it's in the LM)
1033 @c Replace with more factual directions
1035 Recall that we wanted to change the position of the @b{2} in
1037 @lilypond[quote,fragment,relative=2,verbatim]
1043 Since the @b{2} is vertically positioned next to its note, we have to
1044 meddle with the interface associated with this positioning. This is
1045 done using @code{side-position-interface}. The page for this interface
1049 @code{side-position-interface}
1051 Position a victim object (this one) next to other objects (the
1052 support). The property @code{direction} signifies where to put the
1053 victim object relative to the support (left or right, up or down?)
1058 Below this description, the variable @code{padding} is described as
1063 (dimension, in staff space)
1065 Add this much extra space between objects that are next to each other.
1069 By increasing the value of @code{padding}, we can move the
1070 fingering away from the note head. The following command inserts
1071 3 staff spaces of white
1072 between the note and the fingering:
1074 \once \override Voice.Fingering #'padding = #3
1077 Inserting this command before the Fingering object is created,
1078 i.e., before @code{c2}, yields the following result:
1080 @lilypond[quote,relative=2,fragment,verbatim]
1081 \once \override Voice.Fingering #'padding = #3
1088 In this case, the context for this tweak is @code{Voice}. This
1089 fact can also be deduced from the program reference, for the page for
1090 the @rinternals{Fingering_engraver} plug-in says
1093 Fingering_engraver is part of contexts: @dots{} @rinternals{Voice}
1097 @node Naming conventions
1098 @subsection Naming conventions
1100 Another thing that is needed, is an overview of the various naming
1103 scheme functions: lowercase-with-hyphens (incl. one-word
1105 scheme functions: ly:plus-scheme-style
1106 music events, music classes and music properties:
1108 Grob interfaces: scheme-style
1109 backend properties: scheme-style (but X and Y!)
1110 contexts (and MusicExpressions and grobs): Capitalized or
1112 context properties: lowercaseFollowedByCamelCase
1114 Capitalized_followed_by_lowercase_and_with_underscores
1116 Which of these are conventions and which are rules?
1117 Which are rules of the underlying language, and which are
1121 @node Modifying properties
1122 @section Modifying properties
1125 * Overview of modifying properties::
1126 * The \set command::
1127 * The \override command::
1128 * \set versus \override::
1129 * Objects connected to the input::
1133 @node Overview of modifying properties
1134 @subsection Overview of modifying properties
1136 Each context is responsible for creating certain types of graphical
1137 objects. The settings used for printing these objects are also stored by
1138 context. By changing these settings, the appearance of objects can be
1141 The syntax for this is
1144 \override @var{context}.@var{name} #'@var{property} = #@var{value}
1147 Here @var{name} is the name of a graphical object, like
1148 @code{Stem} or @code{NoteHead}, and @var{property} is an internal
1149 variable of the formatting system (@q{grob property} or @q{layout
1150 property}). The latter is a symbol, so it must be quoted. The
1151 subsection @ref{Modifying properties}, explains what to fill in
1152 for @var{name}, @var{property}, and @var{value}. Here we only
1153 discuss the functionality of this command.
1158 \override Staff.Stem #'thickness = #4.0
1162 makes stems thicker (the default is 1.3, with staff line thickness as a
1163 unit). Since the command specifies @code{Staff} as context, it only
1164 applies to the current staff. Other staves will keep their normal
1165 appearance. Here we see the command in action:
1167 @lilypond[quote,verbatim,relative=2,fragment]
1169 \override Staff.Stem #'thickness = #4.0
1175 The @code{\override} command changes the definition of the @code{Stem}
1176 within the current @code{Staff}. After the command is interpreted
1177 all stems are thickened.
1179 Analogous to @code{\set}, the @var{context} argument may be left out,
1180 causing the default context @code{Voice} to be used. Adding
1181 @code{\once} applies the change during one timestep only.
1183 @lilypond[quote,fragment,verbatim,relative=2]
1185 \once \override Stem #'thickness = #4.0
1190 The @code{\override} must be done before the object is
1191 started. Therefore, when altering @emph{Spanner} objects such as slurs
1192 or beams, the @code{\override} command must be executed at the moment
1193 when the object is created. In this example,
1195 @lilypond[quote,fragment,verbatim,relative=2]
1196 \override Slur #'thickness = #3.0
1198 \override Beam #'thickness = #0.6
1203 the slur is fatter but the beam is not. This is because the command for
1204 @code{Beam} comes after the Beam is started, so it has no effect.
1206 Analogous to @code{\unset}, the @code{\revert} command for a context
1207 undoes an @code{\override} command; like with @code{\unset}, it only
1208 affects settings that were made in the same context. In other words, the
1209 @code{\revert} in the next example does not do anything.
1212 \override Voice.Stem #'thickness = #4.0
1213 \revert Staff.Stem #'thickness
1216 Some tweakable options are called @q{subproperties} and reside inside
1217 properties. To tweak those, use commands of the form
1219 @c leave this as a long long
1221 \override @var{context}.@var{name} #'@var{property} #'@var{subproperty} = #@var{value}
1228 \override Stem #'details #'beamed-lengths = #'(4 4 3)
1234 Internals: @rinternals{OverrideProperty}, @rinternals{RevertProperty},
1235 @rinternals{PropertySet}, @rinternals{Backend}, and
1236 @rinternals{All layout objects}.
1241 The back-end is not very strict in type-checking object properties.
1242 Cyclic references in Scheme values for properties can cause hangs
1243 or crashes, or both.
1247 @node The \set command
1248 @subsection The @code{\set} command
1252 @cindex changing properties
1254 Each context can have different @emph{properties}, variables contained
1255 in that context. They can be changed during the interpretation step.
1256 This is achieved by inserting the @code{\set} command in the music,
1259 \set @var{context}.@var{prop} = #@var{value}
1263 @lilypond[quote,verbatim,relative=2,fragment]
1265 \set Score.skipBars = ##t
1269 This command skips measures that have no notes. The result is that
1270 multi-rests are condensed. The value assigned is a Scheme object. In
1271 this case, it is @code{#t}, the boolean True value.
1273 If the @var{context} argument is left out, then the current bottom-most
1274 context (typically @code{ChordNames}, @code{Voice}, or
1275 @code{Lyrics}) is used. In this example,
1277 @lilypond[quote,verbatim,relative=2,fragment]
1279 \set autoBeaming = ##f
1284 the @var{context} argument to @code{\set} is left out, so automatic
1285 beaming is switched off in the current @rinternals{Voice}. Note that
1286 the bottom-most context does not always contain the property that you
1287 wish to change -- for example, attempting to set the @code{skipBars}
1288 property (of the bottom-most context, in this case @code{Voice}) will
1291 @lilypond[quote,verbatim,relative=2,fragment]
1297 Contexts are hierarchical, so if a bigger context was specified, for
1298 example @code{Staff}, then the change would also apply to all
1299 @code{Voice}s in the current stave. The change is applied
1300 @q{on-the-fly}, during the music, so that the setting only affects the
1301 second group of eighth notes.
1305 There is also an @code{\unset} command,
1307 \unset @var{context}.@var{prop}
1311 which removes the definition of @var{prop}. This command removes
1312 the definition only if it is set in @var{context}, so
1315 \set Staff.autoBeaming = ##f
1319 introduces a property setting at @code{Staff} level. The setting also
1320 applies to the current @code{Voice}. However,
1323 \unset Voice.autoBeaming
1327 does not have any effect. To cancel this setting, the @code{\unset}
1328 must be specified on the same level as the original @code{\set}. In
1329 other words, undoing the effect of @code{Staff.autoBeaming = ##f}
1332 \unset Staff.autoBeaming
1335 Like @code{\set}, the @var{context} argument does not have to be
1336 specified for a bottom context, so the two statements
1339 \set Voice.autoBeaming = ##t
1340 \set autoBeaming = ##t
1348 Settings that should only apply to a single time-step can be entered
1349 with @code{\once}, for example in
1351 @lilypond[quote,verbatim,relative=2,fragment]
1353 \once \set fontSize = #4.7
1358 the property @code{fontSize} is unset automatically after the second
1361 A full description of all available context properties is in the
1362 program reference, see
1364 @rinternals{Tunable context properties}.
1367 Translation @expansion{} Tunable context properties.
1372 @node The \override command
1373 @subsection The @code{\override} command
1375 Commands which change output generally look like
1378 \override Voice.Stem #'thickness = #3.0
1382 To construct this tweak we must determine these bits of information:
1385 @item the context: here @code{Voice}.
1386 @item the layout object: here @code{Stem}.
1387 @item the layout property: here @code{thickness}.
1388 @item a sensible value: here @code{3.0}.
1391 Some tweakable options are called @q{subproperties} and reside inside
1392 properties. To tweak those, use commands in the form
1395 \override Stem #'details #'beamed-lengths = #'(4 4 3)
1398 @cindex internal documentation
1399 @cindex finding graphical objects
1400 @cindex graphical object descriptions
1403 @cindex internal documentation
1405 For many properties, regardless of the data type of the property, setting the
1406 property to false ( @code{##f} ) will result in turning it off, causing
1407 LilyPond to ignore that property entirely. This is particularly useful for
1408 turning off grob properties which may otherwise be causing problems.
1410 We demonstrate how to glean this information from the notation manual
1411 and the program reference.
1414 @node \set versus \override
1415 @subsection @code{\set} vs. @code{\override}
1417 We have seen two methods of changing properties: @code{\set} and
1418 @code{\override}. There are actually two different kinds of
1421 Contexts can have properties, which are usually named in
1422 @code{studlyCaps}. They mostly control the translation from
1423 music to notation, eg. @code{localKeySignature} (for determining
1424 whether to print accidentals), @code{measurePosition} (for
1425 determining when to print a bar line). Context properties can
1426 change value over time while interpreting a piece of music;
1427 @code{measurePosition} is an obvious example of
1428 this. Context properties are modified with @code{\set}.
1430 There is a special type of context property: the element
1431 description. These properties are named in @code{StudlyCaps}
1432 (starting with capital letters). They contain the
1433 @q{default settings} for said graphical object as an
1434 association list. See @file{scm/@/define@/-grobs@/.scm}
1435 to see what kind of settings there are. Element descriptions
1436 may be modified with @code{\override}.
1438 @code{\override} is actually a shorthand;
1441 \override @var{context}.@var{name} #'@var{property} = #@var{value}
1445 is more or less equivalent to
1447 @c leave this long line -gp
1449 \set @var{context}.@var{name} #'@var{property} = #(cons (cons '@var{property} @var{value}) <previous value of @var{context})
1452 The value of @code{context} (the alist) is used to initialize
1453 the properties of individual grobs. Grobs also have
1454 properties, named in Scheme style, with
1455 @code{dashed-words}. The values of grob properties change
1456 during the formatting process: formatting basically amounts
1457 to computing properties using callback functions.
1459 @code{fontSize} is a special property: it is equivalent to
1460 entering @code{\override ... #'font-size} for all pertinent
1461 objects. Since this is a common change, the special
1462 property (modified with @code{\set}) was created.
1465 @node Objects connected to the input
1466 @subsection Objects connected to the input
1468 TODO: can't use \tweak in a variable
1472 In some cases, it is possible to take a short-cut for tuning graphical
1473 objects. For objects that result directly from a piece of the input,
1474 you can use the @code{\tweak} function, for example
1476 @lilypond[relative=2,fragment,verbatim,ragged-right]
1479 \tweak #'color #red d
1481 \tweak #'duration-log #1 a
1482 >4-\tweak #'padding #10 -.
1485 As you can see, properties are set in the objects directly,
1486 without mentioning the grob name or context where this should be
1489 This technique only works for objects that are directly connected to
1490 an @rinternals{Event} from the input, for example
1493 @item note heads, caused by chord-pitch (i.e., notes inside a chord)
1494 @item articulation signs, caused by articulation instructions
1497 It notably does not work for stems and accidentals (these are caused
1498 by note heads, not by music events) or clefs (these are not caused by
1499 music inputs, but rather by the change of a property value).
1501 There are very few objects which are @emph{directly} connected to
1502 output. A normal note (like @code{c4}) is not directly connected
1506 \tweak #'color #red c4
1510 does not change color. See @ref{Displaying music expressions}, for
1514 @node Useful concepts and properties
1515 @section Useful concepts and properties
1520 * Direction and placement::
1521 * Distances and measurements::
1526 @subsection Input modes
1528 The way in which the notation contained within an input file is
1529 interpreted is determined by the current input mode.
1533 This is activated with the @code{\chordmode} command, and causes
1534 input to be interpreted with the syntax of chord notation, see
1535 @ref{Chord notation}. Chords are rendered as notes on a staff.
1537 Chord mode is also activated with the @code{\chords} command.
1538 This also creates a new @code{ChordNames} context and
1539 causes the following input to be interpreted with the syntax of
1540 chord notation and rendered as chord names in the @code{ChordNames}
1541 context, see @ref{Printing chord names}.
1545 This is activated with the @code{\drummode} command, and causes
1546 input to be interpreted with the syntax of drum notation, see
1547 @ref{Basic percussion notation}.
1549 Drum mode is also activated with the @code{\drums} command.
1550 This also creates a new @code{DrumStaff} context and causes the
1551 following input to be interpreted with the syntax of drum notation
1552 and rendered as drum symbols on a drum staff, see @ref{Basic
1553 percussion notation}.
1555 @strong{Figure mode}
1557 This is activated with the @code{\figuremode} command, and causes
1558 input to be interpreted with the syntax of figured bass, see
1559 @ref{Entering figured bass}.
1561 Figure mode is also activated with the @code{\figures} command.
1562 This also creates a new @code{FiguredBass} context and causes the
1563 following input to be interpreted with the figured bass syntax
1564 and rendered as figured bass symbols in the @code{FiguredBass}
1565 context, see @ref{Introduction to figured bass}.
1567 @strong{Fret and tab modes}
1569 There are no special input modes for entering fret and tab symbols.
1571 To create tab diagrams, enter notes or chords in note mode and
1572 render them in a @code{TabStaff} context, see
1573 @ref{Default tablatures}.
1575 To create fret diagrams above a staff, you have two choices.
1576 You can either use the @code{FretBoards} context (see
1577 @ref{Automatic fret diagrams} or you can enter them as a markup
1578 above the notes using the @code{\fret-diagram} command (see
1579 @ref{Fret diagram markups}).
1581 @strong{Lyrics mode}
1583 This is activated with the @code{\lyricmode} command, and causes
1584 input to be interpreted as lyric syllables with optional durations
1585 and associated lyric modifiers, see @ref{Vocal music}.
1587 Lyric mode is also activated with the @code{\addlyrics} command.
1588 This also creates a new @code{Lyrics} context and an implicit
1589 @code{\lyricsto} command which associates the following lyrics
1590 with the preceding music.
1592 @strong{Markup mode}
1594 This is activated with the @code{\markup} command, and causes
1595 input to be interpreted with the syntax of markup, see
1596 @ref{Text markup commands}.
1598 @c silly work-around for texinfo broken-ness
1599 @c (@strong{Note...} causes a spurious cross-reference in Info)
1602 This is the default mode or it may be activated with the
1603 @code{\notemode} command. Input is interpreted as pitches,
1604 durations, markup, etc and typeset as musical notation on a staff.
1606 It is not normally necessary to specify note mode explicitly, but
1607 it may be useful to do so in certain situations, for example if you
1608 are in lyric mode, chord mode or any other mode and want to insert
1609 something that only can be done with note mode syntax.
1611 For example, to indicate dynamic markings for the verses of a
1612 choral pieces it is necessary to enter note mode to interpret
1615 @lilypond[verbatim,relative=2,quote]
1618 \notemode{\set stanza = \markup{ \dynamic f 1. } }
1622 \notemode{\set stanza = \markup{ \dynamic p 2. } }
1629 @node Direction and placement
1630 @subsection Direction and placement
1632 In typesetting music the direction and placement of many items is
1633 a matter of choice. For example, the stems of notes can
1634 be directed up or down; lyrics, dynamics, and other expressive
1635 marks may be placed above or below the staff; text may be aligned
1636 left, right or center; etc. Most of these choices may be left to
1637 be determined automatically by LilyPond, but in some cases it may
1638 be desirable to force a particular direction or placement.
1640 @strong{Default actions}
1642 By default some directions are always up or always down (e.g.
1643 dynamics or fermata), while other things can alternate between
1644 up or down based on the stem direction (like slurs or accents).
1646 @c TODO Add table showing these
1648 @strong{Context layout}
1650 Contexts are positioned in a system from top to bottom in the
1651 order in which they are encountered. Note, however, that a
1652 context will be created implicitly if a command is encountered
1653 when there is no suitable context available to contain it.
1655 @c TODO Add example ?
1657 The default order in which contexts are laid out can be changed,
1658 see @ref{Aligning contexts}
1660 @strong{Articulation direction indicators}
1662 When adding articulations to notes the direction indicator,
1663 @code{^} (meaning @qq{up}), @code{_} (meaning @qq{down}) or
1664 @code{-} (meaning @qq{use default direction}), can usually be
1665 omitted, in which case @code{-} is assumed. But a direction
1666 indicator is @strong{always} required before
1669 @item @code{\tweak} commands
1670 @item @code{\markup} commands
1671 @item @code{\tag} commands
1672 @item string markups, e.g. -"string"
1673 @item fingering instructions, e.g. @code{-1}
1674 @item articulation shortcuts, e.g. @code{-.}, @code{->}, @code{--}
1677 @strong{The direction property}
1679 The position or direction of many layout objects is controlled
1680 by the @code{direction} property.
1682 The value of the @code{direction} property may be
1683 set to @code{1}, meaning @qq{up} or @qq{above}, or to @code{-1},
1684 meaning @qq{down} or @qq{below}. The symbols @code{UP} and
1685 @code{DOWN} may be used instead of @code{1} and @code{-1}
1686 respectively. The default direction may be specified by setting
1687 @code{direction} to @code{0} or @code{CENTER}. Alternatively,
1688 in many cases predefined commands
1689 exist to specify the direction. These are all of the form
1692 @code{\xxxUp}, @code{xxxDown}, @code{xxxNeutral}
1695 where @code{xxxNeutral} means @qq{use the default direction}.
1696 See @rlearning{Within-staff objects}.
1698 In a few cases, arpeggio being the only common example, the value
1699 of the @code{direction} property specifies whether the object
1700 is to be placed to the right or left of the parent object. In
1701 this case @code{-1} or @code{LEFT} means @qq{to the left} and
1702 @code{1} or @code{RIGHT} means @qq{to the right}. @code{0}
1703 or @code{CENTER} means @qq{use the default} direction, as before.
1706 These all have side-axis set to #X
1707 AmbitusAccidental - direction has no effect
1709 StanzaNumber - not tried
1710 TrillPitchAccidental - not tried
1711 TrillPitchGroup - not tried
1716 @node Distances and measurements
1717 @subsection Distances and measurements
1719 DISCUSS after working on other sections.
1721 TODO: staff spaces. Maybe move into tweaks?
1725 @subsection Spanners
1727 Many objects of musical notation extend over several notes or even
1728 several bars. Examples are crescendi, trills, tuplet brackets, and
1729 volta repeat brackets. Such objects are called @qq{spanners}, and
1730 have special properties to control their appearance and behaviour.
1731 Some of these properties are common to all spanners; others are
1732 restricted to a sub-set of the spanners.
1734 @node Common properties
1735 @section Common properties
1738 * Controlling visibility of objects::
1740 * Rotating objects::
1741 * Aligning objects::
1744 @c TODO Add new subsection Shapes of objects
1745 @c which would include Slur shapes
1746 @c with a Known issue: can't modify shapes with 'control-points if there are
1747 @c more than one at the same musical moment
1749 @node Controlling visibility of objects
1750 @subsection Controlling visibility of objects
1752 @cindex objects, visibility of
1753 @cindex grobs, visibility of
1754 @cindex visibility of objects
1756 There are four main ways in which the visibility of layout objects
1757 can be controlled: their stencil can be removed, they can be made
1758 transparent, they can be colored white, or their
1759 @code{break-visibility} property can be overridden. The first
1760 three apply to all layout objects; the last to just a few -- the
1761 @emph{breakable} objects. The Learning Manual introduces these
1762 four techniques, see @rlearning{Visibility and color of objects}.
1764 There are also a few other techniques which are specific to
1765 certain layout objects. These are covered under Special
1769 * Removing the stencil::
1770 * Making objects transparent::
1771 * Painting objects white::
1772 * Using break-visibility::
1773 * Special considerations::
1777 @node Removing the stencil
1778 @unnumberedsubsubsec Removing the stencil
1780 @cindex stencil, removing
1782 Every layout object has a stencil property. By default this is set
1783 to the specific function which draws that object. If this property
1784 is overridden to @code{#f} no function will be called and the object
1785 will not be drawn. The default action can be recovered with
1788 @lilypond[quote,verbatim,relative=1]
1790 \override Score.BarLine #'stencil = ##f
1792 \revert Score.BarLine #'stencil
1796 @node Making objects transparent
1797 @unnumberedsubsubsec Making objects transparent
1799 @cindex transparent, making objects
1801 Every layout object has a transparent property which by default is
1802 set to @code{#f}. If set to @code{#t} the object still occupies
1803 space but is made invisible.
1805 @lilypond[quote,verbatim,relative=2]
1807 \once \override NoteHead #'transparent = ##t
1811 @node Painting objects white
1812 @unnumberedsubsubsec Painting objects white
1814 @cindex objects, coloring
1815 @cindex coloring objects
1817 @cindex printing order
1818 @cindex overwriting objects
1819 @cindex objects, overwriting
1820 @cindex grobs, overwriting
1822 Every layout object has a color property which by default is set
1823 to @code{black}. If this is overridden to @code{white} the object
1824 will be indistinguishable from the white background. However,
1825 if the object crosses other objects the color of the crossing
1826 points will be determined by the order in which they are drawn,
1827 and this may leave a ghostly image of the white object, as shown
1830 @lilypond[quote,verbatim,relative=2]
1831 \override Staff.Clef #'color = #white
1835 This may be avoided by changing the order of printing the objects.
1836 All layout objects have a @code{layer} property which takes a real
1837 number. Objects with the lowest value of @code{layer} are drawn
1838 first, then objects with progressively higher values are drawn, so
1839 objects with higher values overwrite objects with lower values.
1840 By default most objects are assigned a @code{layer} value of
1841 @code{1}, although a few objects, including @code{StaffSymbol} and
1842 @code{BarLine}, are assigned a value of @code{0}. The order of
1843 printing objects with the same nominal value of @code{layer} is
1846 In the example above the white clef, with a default @code{layer}
1847 value of @code{1}, is drawn after the staff lines (default
1848 @code{layer} value @code{0}), so overwriting them. To change this,
1849 the @code{Clef} object must be given in a lower value of
1850 @code{layer}, say @code{-1}, so that it is drawn earlier:
1852 @lilypond[quote,verbatim,relative=2]
1853 \override Staff.Clef #'color = #white
1854 \override Staff.Clef #'layer = #-1
1858 @node Using break-visibility
1859 @unnumberedsubsubsec Using break-visibility
1861 @cindex break-visibility
1863 Most layout objects are printed only once, but some like
1864 bar lines, clefs, time signatures and key signatures, may need
1865 to be printed twice when a line break occurs -- once at the end
1866 of the line and again at the start of the next line. Such
1867 objects are called @emph{breakable}, and have a property, the
1868 @code{break-visibility} property to control their visibility
1869 at the three positions in which they may appear -- at the
1870 start of a line, within a line if they are changed, and at the
1871 end of a line if a change takes place there.
1873 For example, the time signature
1874 by default will be printed at the start of the first line, but
1875 nowhere else unless it changes, when it will be printed at the
1876 point at which the change occurs. If this change occurs at the
1877 end of a line the new time signature will be printed at the start
1878 of the next line and a cautionary time signature will be printed
1879 at the end of the previous line as well.
1881 This behaviour is controlled by the @code{break-visibility}
1882 property, which is explained in @rlearning{Visibility and color of
1883 objects}. This property takes a vector of three booleans which,
1884 in order, determine whether the object is printed at the end of,
1885 within the body of, or at the beginning of a line. Or to be more
1886 precise, before a line break, where there is no line break, or
1889 Alternatively, seven of the eight combinations may be specified
1890 by pre-defined functions, defined in @file{scm/output-lib.scm},
1891 where the last three columns indicate whether the layout objects
1892 will be visible in the positions shown at the head of the columns:
1894 @multitable @columnfractions .40 .15 .15 .15 .15
1895 @c TODO check these more carefully
1896 @headitem Function @tab Vector @tab Before @tab At no @tab After
1897 @headitem form @tab form @tab break @tab break @tab break
1899 @item @code{all-invisible} @tab @code{'#(#f #f #f)} @ @ @tab no @tab no @tab no
1900 @item @code{begin-of-line-visible} @tab @code{'#(#f #f #t)} @tab no @tab no @tab yes
1901 @item @code{end-of-line-visible} @tab @code{'#(#t #f #f)} @tab yes @tab no @tab no
1902 @item @code{all-visible} @tab @code{'#(#t #t #t)} @tab yes @tab yes @tab yes
1903 @c The center-visible function is not defined
1904 @c @item @code{center-visible} @tab @code{'#(#f #t #f)} @tab no @tab yes @tab no
1905 @item @code{begin-of-line-invisible} @tab @code{'#(#t #t #f)} @tab yes @tab yes @tab no
1906 @item @code{end-of-line-invisible} @tab @code{'#(#f #t #t)} @tab no @tab yes @tab yes
1907 @item @code{center-invisible} @tab @code{'#(#t #f #t)} @tab yes @tab no @tab yes
1910 The @code{center-visible} function is not pre-defined.
1912 The default settings of @code{break-visibility} depend on the
1913 layout object. The following table shows all the layout objects
1914 of interest which are affected by @code{break-visibility} and the
1915 default setting of this property:
1917 @multitable @columnfractions .3 .3 .4
1919 @headitem Layout object @tab Usual context @tab Default setting
1921 @c omit Ambitus as it appears not to be affected by break-visibility -td
1922 @c @item @code{Ambitus} @tab as specified @tab @code{begin-of-line-visible}
1923 @item @code{BarLine} @tab @code{Score} @tab calculated
1924 @item @code{BarNumber} @tab @code{Score} @tab @code{begin-of-line-visible}
1925 @c omit the following item until it can be explained -td
1926 @c @item @code{BreakAlignGroup} @tab @code{Score} @tab calculated
1927 @item @code{BreathingSign} @tab @code{Voice} @tab @code{begin-of-line-invisible}
1928 @item @code{Clef} @tab @code{Staff} @tab @code{begin-of-line-visible}
1929 @item @code{Custos} @tab @code{Staff} @tab @code{end-of-line-visible}
1930 @item @code{DoublePercentRepeat} @tab @code{Voice} @tab @code{begin-of-line-invisible}
1931 @c omit KeyCancellation until it can be explained -td
1932 @c @item @code{KeyCancellation} @tab ?? @tab @code{begin-of-line-invisible}
1933 @item @code{KeySignature} @tab @code{Staff} @tab @code{begin-of-line-visible}
1934 @c omit LeftEdge until it can be explained -td
1935 @c @item @code{LeftEdge} @tab @code{Score} @tab @code{center-invisible}
1936 @item @code{OctavateEight} @tab @code{Staff} @tab @code{begin-of-line-visible}
1937 @item @code{RehearsalMark} @tab @code{Score} @tab @code{end-of-line-invisible}
1938 @item @code{TimeSignature} @tab @code{Staff} @tab @code{all-visible}
1942 The example below shows the use of the vector form to control the
1943 visibility of barlines:
1945 @lilypond[quote,verbatim,relative=1,ragged-right]
1948 % Remove bar line at the end of the current line
1949 \once \override Score.BarLine #'break-visibility = #'#(#f #t #t)
1955 Although all three components of the vector used to override
1956 @code{break-visibility} must be present, not all of them are
1957 effective with every layout object, and some combinations may
1958 even give errors. The following limitations apply:
1961 @item Bar lines cannot be printed at start of line.
1962 @item A bar number cannot be printed at the start of the first
1963 line unless it is set to be different from 1.
1964 @item Clef -- see below
1965 @item Double percent repeats are either all printed or all
1966 suppressed. Use begin-of line-invisible to print and
1967 all-invisible to suppress.
1968 @item Key signature -- see below
1969 @item OctavateEight -- see below
1972 @node Special considerations
1973 @unnumberedsubsubsec Special considerations
1975 @strong{@emph{Visibility following explicit changes}}
1977 @cindex key signature, visibility following explicit change
1978 @cindex explicitKeySignatureVisibility
1979 @cindex clef, visibility following explicit change
1980 @cindex explicitClefVisibility
1982 The @code{break-visibility} property controls the visibility of
1983 key signatures and changes of clef only at the start of lines,
1984 i.e. after a break. It has no effect on the visibility of the
1985 key signature or clef following an explicit key change or an
1986 explicit clef change within or at the end of a line. In the
1987 following example the key signature following the explicit change
1988 to B-flat major is still visible, even though @code{all-invisible}
1991 @lilypond[quote,verbatim,relative=1,ragged-right]
1994 % Try to remove all key signatures
1995 \override Staff.KeySignature #'break-visibility = #all-invisible
2003 The visibility of such explicit key signature and clef changes is
2004 controlled by the @code{explicitKeySignatureVisibility} and
2005 @code{explicitClefVisibility} properties. These are the equivalent
2006 of the @code{break-visibility} property and both take a vector of
2007 three booleans or the predefined functions listed above, exactly like
2008 @code{break-visibility}. Both are properties of the Staff context,
2009 not the layout objects themselves, and so they are set using the
2010 @code{\set} command. Both are set by default to @code{all-visible}.
2011 These properties control only the visibility of key signatures and
2012 clefs resulting from explicit changes and do not affect key
2013 signatures and clefs at the beginning of lines;
2014 @code{break-visibility} must still be overridden in the appropriate
2015 object to remove these.
2017 @lilypond[quote,verbatim,relative=1,ragged-right]
2020 \set Staff.explicitKeySignatureVisibility = #all-invisible
2021 \override Staff.KeySignature #'break-visibility = #all-invisible
2028 @strong{@emph{Visibility of cautionary accidentals}}
2030 To remove the cautionary accidentals printed at an explicit key
2031 change, set the Staff context property @code{printKeyCancellation}
2034 @lilypond[quote,verbatim,relative=1,ragged-right]
2037 \set Staff.explicitKeySignatureVisibility = #all-invisible
2038 \set Staff.printKeyCancellation = ##f
2039 \override Staff.KeySignature #'break-visibility = #all-invisible
2046 With these overrides only the accidentals before the notes remain
2047 to indicate the change of key.
2049 @c TODO Add visibility of cautionary accidentals before notes
2051 @strong{@emph{Automatic bars}}
2053 @cindex automaticBars
2054 @cindex bar lines, suppressing
2056 As a special case, the printing of bar lines can also be turned off
2057 by setting the @code{automaticBars} property in the Score context.
2058 If set to @code{#f}, bar lines will not be printed automatically;
2059 they must be explicitly created with a @code{\bar} command. Unlike
2060 the @code{\cadenzaOn} predefined command, measures are still counted.
2061 Bar generation will resume according to that count if this property
2062 is later set to @code{#t}. When set to @code{#f}, line breaks can
2063 occur only at explicit @code{\bar} commands.
2067 @strong{@emph{Octavated clefs}}
2069 @cindex octavated clefs, visibility of
2070 @cindex visibility of octavated clefs
2071 @cindex clefs, visibility of octavation
2073 The small octavation symbol on octavated clefs is produced by the
2074 @code{OctavateEight} layout object. Its visibility is controlled
2075 independently from that of the @code{Clef} object, so it is
2076 necessary to apply any required @code{break-visibility} overrides
2077 to both the @code{Clef} and the @code{OctavateEight} layout objects
2078 to fully suppress such clef symbols at the start of each line.
2080 For explicit clef changes, the @code{explicitClefVisibility}
2081 property controls both the clef symbol and any octavation symbol
2087 @rlearning{Visibility and color of objects}
2091 @subsection Line styles
2093 @c TODO: split the following explanations between expressive marks and
2094 @c text-related stuff. Perhaps create a new subsection named
2095 @c "Spanner limits", "Spanner boundaries"? -vv
2097 Some performance indications, e.g., @i{rallentando} and
2098 @i{accelerando} and @i{trills} are written as text and are
2099 extended over many measures with lines, sometimes dotted or wavy.
2101 These all use the same routines as the glissando for drawing the
2102 texts and the lines, and tuning their behavior is therefore also
2103 done in the same way. It is done with a spanner, and the routine
2104 responsible for drawing the spanners is
2105 @code{ly:line-interface::print}. This routine determines the
2106 exact location of the two @i{span points} and draws a line in
2107 between, in the style requested.
2109 Here is an example of the different line styles available, and how
2112 @lilypond[relative=2,ragged-right,verbatim,fragment]
2114 \once \override Glissando #'style = #'dashed-line
2116 \override Glissando #'style = #'dotted-line
2118 \override Glissando #'style = #'zigzag
2120 \override Glissando #'style = #'trill
2124 The information that determines the end-points is computed
2125 on-the-fly for every graphic object, but it is possible to
2128 @lilypond[relative=2,ragged-right,verbatim,fragment]
2130 \once \override Glissando #'bound-details #'right #'Y = #-2
2134 The @code{Glissando} object, like any other using the
2135 @code{ly:line-interface::print} routine, carries a nested
2136 association list. In the above statement, the value for @code{Y}
2137 is set to @code{-2} for the association list corresponding to the
2138 right end point. Of course, it is also possible to adjust the
2139 left side with @code{left} instead of @code{right}.
2141 If @code{Y} is not set, the value is computed from the vertical
2142 position of right attachment point of the spanner.
2144 In case of a line break, the values for the span-points are
2145 extended with contents of the @code{left-broken} and
2146 @code{right-broken} sublists, for example
2148 @lilypond[relative=2,ragged-right,verbatim,fragment]
2149 \override Glissando #'breakable = ##T
2150 \override Glissando #'bound-details #'right-broken #'Y = #-3
2151 c1 \glissando \break
2155 The following properties can be used for the
2159 This sets the Y-coordinate of the end point, in staff space. By
2160 default, it is the center of the bound object, so for a glissando
2161 it points to the vertical center of the note head.
2163 For horizontal spanners, such as text spanner and trill spanners,
2164 it is hardcoded to 0.
2167 This determines where the line starts and ends in X-direction,
2168 relative to the bound object. So, a value of @code{-1} (or
2169 @code{LEFT}) makes the line start/end at the left side of the note
2170 head it is attached to.
2173 This is the absolute coordinate of the end point. It is usually
2174 computed on the fly, and there is little use in overriding it.
2177 Line spanners may have symbols at the beginning or end, which is
2178 contained in this sub-property. This is for internal use, it is
2179 recommended to use @code{text}.
2182 This is a markup that is evaluated to yield stencil. It is used
2183 to put @i{cresc.} and @i{tr} on horizontal spanners.
2185 @lilypond[quote,ragged-right,fragment,relative=2,verbatim]
2186 \override TextSpanner #'bound-details #'left #'text
2187 = \markup { \small \bold Slower }
2188 c2\startTextSpan b c a\stopTextSpan
2191 @item stencil-align-dir-y
2192 @item stencil-offset
2193 Without setting this, the stencil is simply put there at the
2194 end-point, as defined by the @code{X} and @code{Y} sub properties.
2195 Setting either @code{stencil-align-dir-y} or @code{stencil-offset}
2196 will move the symbol at the edge relative to the end point of the
2199 @lilypond[relative=1,fragment,verbatim]
2200 \override TextSpanner #'bound-details
2201 #'left #'stencil-align-dir-y = #DOWN
2202 \override TextSpanner #'bound-details
2203 #'right #'stencil-align-dir-y = #UP
2205 \override TextSpanner #'bound-details
2206 #'left #'text = #"gggg"
2207 \override TextSpanner #'bound-details
2208 #'right #'text = #"hhhh"
2209 c4^\startTextSpan c c c \stopTextSpan
2213 Setting this sub property to @code{#t} produce an arrowhead at the
2217 This sub property controls the space between the specified
2218 end-point of the line and the actual end. Without padding, a
2219 glissando would start and end in the center of each note head.
2223 @c TODO: Move to 5.4.4
2225 The music function \endSpanners terminates spanners and hairpins
2226 after exactly one note.
2228 @lilypond[verbatim,quote,ragged-right,relative=2,fragment]
2230 c2 \startTextSpan c2
2234 When using \endSpanners it is not necessary to close
2235 \startTextSpan with \stopTextSpan, nor is it necessary to close
2242 Internals Reference: @rinternals{TextSpanner},
2243 @rinternals{Glissando}, @rinternals{VoiceFollower},
2244 @rinternals{TrillSpanner},
2245 @rinternals{line-spanner-interface}.
2248 @node Rotating objects
2249 @subsection Rotating objects
2251 @c FIXME Write this section
2253 @node Aligning objects
2254 @subsection Aligning objects
2256 @c FIXME Write this section
2259 @node Advanced tweaks
2260 @section Advanced tweaks
2263 * Vertical grouping of grobs::
2264 * Modifying ends of spanners::
2265 * Modifying stencils::
2266 * Modifying shapes::
2272 @node Vertical grouping of grobs
2273 @subsection Vertical grouping of grobs
2275 @c FIXME Expand this section
2277 The VerticalAlignment and VerticalAxisGroup grobs work together.
2278 VerticalAxisGroup groups together different grobs like Staff, Lyrics,
2279 etc. VerticalAlignment then vertically aligns the different grobs
2280 grouped together by VerticalAxisGroup. There is usually only one
2281 VerticalAlignment per score but every Staff, Lyrics, etc. has its own
2285 @node Modifying ends of spanners
2286 @subsection Modifying ends of spanners
2288 @c FIXME Write this section
2290 @node Modifying stencils
2291 @subsection Modifying stencils
2293 @c FIXME Write this section
2295 @node Modifying shapes
2296 @subsection Modifying shapes
2298 @c FIXME Write this section
2299 @c Discussion of Bezier curves and the control-points property
2301 @node Discussion of specific tweaks
2302 @section Discussion of specific tweaks
2305 * old Contexts explained::
2309 @node old Contexts explained
2310 @subsection old Contexts explained
2312 @c FIXME Delete this section? It is in LM
2313 @c Or leave heading and go on from LM?
2315 When music is printed, a lot of notational elements must be added to the
2316 output. For example, compare the input and output of the following example:
2318 @lilypond[quote,verbatim,relative=2,fragment]
2322 The input is rather sparse, but in the output, bar lines, accidentals,
2323 clef, and time signature are added. LilyPond @emph{interprets} the
2324 input. During this step, the musical information is inspected in time
2325 order, similar to reading a score from left to right. While reading
2326 the input, the program remembers where measure boundaries are, and which
2327 pitches require explicit accidentals. This information can be presented on
2328 several levels. For example, the effect of an accidental is limited
2329 to a single staff, while a bar line must be synchronized across the
2332 Within LilyPond, these rules and bits of information are grouped in
2333 @emph{Contexts}. Some examples of contexts are @code{Voice},
2334 @code{Staff}, and @code{Score}. They are hierarchical, for
2335 example: a @code{Staff} can contain many @code{Voice}s, and a
2336 @code{Score} can contain many @code{Staff} contexts.
2339 @sourceimage{context-example,5cm,,}
2342 Each context has the responsibility for enforcing some notation rules,
2343 creating some notation objects and maintaining the associated
2344 properties. For example, the @code{Voice} context may introduce an
2345 accidental and then the @code{Staff} context maintains the rule to
2346 show or suppress the accidental for the remainder of the measure. The
2347 synchronization of bar lines is handled at @code{Score} context.
2349 However, in some music we may not want the bar lines to be
2350 synchronized -- consider a polymetric score in 4/4 and 3/4 time. In
2351 such cases, we must modify the default settings of the @code{Score}
2352 and @code{Staff} contexts.
2354 For very simple scores, contexts are created implicitly, and you need
2355 not be aware of them. For larger pieces, such as anything with more
2356 than one staff, they must be
2357 created explicitly to make sure that you get as many staves as you
2358 need, and that they are in the correct order. For typesetting pieces
2359 with specialized notation, it can be useful to modify existing or
2360 to define new contexts.
2363 A complete description of all available contexts is in the program
2366 @rinternals{Contexts}.
2369 Translation @expansion{} Context.
2372 @c [TODO: describe propagation]