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
29 document: @rinternalsnamed{Top,the Internals Reference}. That manual
30 lists all different variables, functions and options available in
31 LilyPond. It is written as a HTML document, which is available
32 @c leave the @uref as one long line.
33 @uref{http://@/lilypond@/.org/@/doc/@/stable/@/Documentation/@/user/@/lilypond@/-internals/,on@/-line},
34 but is also included with the LilyPond documentation package.
36 @c TODO The following is at variance to what actually follows. Fix -td
38 There are four areas where the default settings may be changed:
42 Automatic notation: changing the automatic creation of notation
43 elements. For example, changing the beaming rules.
46 Output: changing the appearance of individual
47 objects. For example, changing stem directions or the location of
51 Context: changing aspects of the translation from music events to
52 notation. For example, giving each staff a separate time signature.
55 Page layout: changing the appearance of the spacing, line
56 breaks, and page dimensions. These modifications are discussed
57 @c in @ref{notation}, and @ref{Spacing issues}.
60 Internally, LilyPond uses Scheme (a LISP dialect) to provide
61 infrastructure. Overriding layout decisions in effect accesses the
62 program internals, which requires Scheme input. Scheme elements are
63 introduced in a @code{.ly} file with the hash mark
64 @code{#}.@footnote{@rlearning{Scheme tutorial}, contains a short tutorial
65 on entering numbers, lists, strings, and symbols in Scheme.}
69 * Interpretation contexts::
70 * Explaining the Internals Reference::
71 * Modifying properties::
72 * Useful concepts and properties::
75 * Discussion of specific tweaks::
79 @node Interpretation contexts
80 @section Interpretation contexts
82 This section describes what contexts are, and how to modify them.
85 * Contexts explained::
87 * Modifying context plug-ins::
88 * Changing context default settings::
89 * Defining new contexts::
94 @node Contexts explained
95 @subsection Contexts explained
98 @c TODO Rethink and rewrite
100 >> > > - list of contexts: my *danger unmaintainable*
101 >> > > alarm just went off. I'm
103 I knew it would... And leaving out some of them is perfectly fine
105 I do think that a list like this, with the main contexts and a
107 description of what they do (perhaps also with a note about what
109 behavior is associated with each of them, but this may be
111 should be there, and then we could simply list the remaining ones
113 further explanation and with links to the IR.
116 @c TODO Improve layout, order and consistency of wording -td
118 @c TODO Add introduction which explains contexts in generality -td
120 Contexts are arranged heirarchically:
123 * Score - the master of all contexts::
124 * Top-level contexts - staff containers::
125 * Intermediate-level contexts - staves::
126 * Bottom-level contexts - voices::
129 @node Score - the master of all contexts
130 @unnumberedsubsubsec Score - the master of all contexts
132 This is the top level notation context. No other context can
133 contain a Score context. By default the Score context handles
134 the administration of time signatures and makes sure that items
135 such as clefs, time signatures, and key-signatures are aligned
138 A Score context is instantiated implicitly when a
139 @code{\score @{@dots{}@}} or @code{\layout @{@dots{}@}} block is
140 processed, or explicitly when a @code{\new Score} command is
143 @node Top-level contexts - staff containers
144 @unnumberedsubsubsec Top-level contexts - staff containers
146 @strong{@emph{StaffGroup}}
148 Groups staves while adding a bracket on the left side, grouping
149 the staves together. The bar lines of the contained staves are
150 connected vertically. StaffGroup only consists of a collection
151 of staves, with a bracket in front and spanning bar lines.
153 @strong{@emph{ChoirStaff}}
155 Identical to StaffGroup except that the bar lines of the contained
156 staves are not connected vertically.
158 @strong{@emph{GrandStaff}}
160 A group of staves, with a brace on the left side, grouping
161 the staves together. The bar lines of the contained staves are
162 connected vertically.
164 @strong{@emph{PianoStaff}}
166 TODO No longer correct? Check. -td
168 Just like GrandStaff but with a forced distance between the
169 staves, so cross staff beaming and slurring can be used.
171 @strong{@emph{InnerStaffGroup}}
175 @strong{@emph{InnerChoirStaff}}
179 @node Intermediate-level contexts - staves
180 @unnumberedsubsubsec Intermediate-level contexts - staves
182 @strong{@emph{Staff}}
184 Handles clefs, bar lines, keys, accidentals. It can contain
187 @strong{@emph{RhythmicStaff}}
189 Like Staff but for printing rhythms. Pitches are ignored;
190 the notes are printed on one line.
192 @strong{@emph{TabStaff}}
194 Context for generating tablature. By default lays the music
195 expression out as a guitar tablature, printed on six lines.
197 @strong{@emph{DrumStaff}}
199 Handles typesetting for percussion. Can contain DrumVoice
201 @strong{@emph{VaticanaStaff}}
203 Same as Staff, except that it is designed for typesetting
204 a piece in gregorian style.
206 @strong{@emph{MensuralStaff}}
208 Same as Staff, except that it is designed for typesetting
209 a piece in mensural style.
211 @node Bottom-level contexts - voices
212 @unnumberedsubsubsec Bottom-level contexts - voices
214 Voice-level contexts initialise certain properties and start
215 appropriate engravers. Being bottom-level contexts, they cannot
216 contain other contexts.
218 @strong{@emph{Voice}}
220 Corresponds to a voice on a staff. This context handles the
221 conversion of dynamic signs, stems, beams, super- and sub-scripts,
222 slurs, ties, and rests. You have to instantiate this explicitly
223 if you require multiple voices on the same staff.
225 @strong{@emph{VaticanaVoice}}
227 Same as Voice, except that it is designed for typesetting a piece
230 @strong{@emph{MensuralVoice}}
232 Same as Voice, with modifications for typesetting a piece in
235 @strong{@emph{Lyrics}}
237 Corresponds to a voice with lyrics. Handles the printing of a
238 single line of lyrics.
240 @strong{@emph{DrumVoice}}
242 The voice context used in a percussion staff.
244 @strong{@emph{FiguredBass}}
246 The context in which BassFigure objects are created from
247 input entered in @code{\figuremode} mode.
249 @strong{@emph{TabVoice}}
251 The voice context used within a TabStaff context. Usually left to
252 be created implicitly.
254 @strong{@emph{ChordNames}}
256 Typesets chord names.
258 ------------------------------
262 Then the following, which I don't know what to do with:
264 * GregorianTranscriptionVoice
265 * GregorianTranscriptionStaff
268 Engraves fretboards from chords. Not easy... Not
270 There is now some documentation on FretBoards in the NR, under
271 instrument-specific notation -- cds.
275 * CueVoice Not documented
277 Hard coded entry point for LilyPond. Cannot be tuned.
279 Silently discards all musical information given to this
283 @node Creating contexts
284 @subsection Creating contexts
286 @c TODO \new Score and \score
287 @c TODO more complete descriptions rather than learning style
289 For scores with only one voice and one staff, contexts are
290 created automatically. For more complex scores, it is necessary to
291 create them by hand. There are three commands that do this.
296 The easiest command is @code{\new}, and it also the quickest to type.
297 It is prepended to a music expression, for example
301 @cindex Context, creating
304 \new @var{type} @var{music expression}
308 where @var{type} is a context name (like @code{Staff} or
309 @code{Voice}). This command creates a new context, and starts
310 interpreting the @var{music expression} with that.
312 A practical application of @code{\new} is a score with many
313 staves. Each part that should be on its own staff, is preceded with
316 @lilypond[quote,verbatim,relative=2,ragged-right,fragment]
323 The @code{\new} command may also give a name to the context,
326 \new @var{type} = @var{id} @var{music}
328 However, this user specified name is only used if there is no other
329 context already earlier with the same name.
335 Like @code{\new}, the @code{\context} command also directs a music
336 expression to a context object, but gives the context an explicit name. The
340 \context @var{type} = @var{id} @var{music}
343 This form will search for an existing context of type @var{type}
344 called @var{id}. If that context does not exist yet, a new
345 context with the specified name is created. This is useful if
346 the context is referred to later on. For example, when
347 setting lyrics the melody is in a named context
350 \context Voice = "@b{tenor}" @var{music}
354 so the texts can be properly aligned to its notes,
357 \new Lyrics \lyricsto "@b{tenor}" @var{lyrics}
362 Another possible use of named contexts is funneling two different
363 music expressions into one context. In the following example,
364 articulations and notes are entered separately,
368 arts = @{ s4-. s4-> @}
371 They are combined by sending both to the same @code{Voice} context,
375 \new Staff \context Voice = "A" \music
376 \context Voice = "A" \arts
379 @lilypond[quote,ragged-right]
383 \new Staff \context Voice = "A" \music
384 \context Voice = "A" \arts
388 With this mechanism, it is possible to define an Urtext (original
389 edition), with the option to put several distinct articulations on the
392 @cindex creating contexts
395 The third command for creating contexts is
397 \context @var{type} @var{music}
402 This is similar to @code{\context} with @code{= @var{id}}, but matches
403 any context of type @var{type}, regardless of its given name.
405 This variant is used with music expressions that can be interpreted at
406 several levels. For example, the @code{\applyOutput} command (see
407 @ref{Running a function on all layout objects}). Without an explicit
408 @code{\context}, it is usually applied to @code{Voice}
411 \applyOutput #'@var{context} #@var{function} % apply to Voice
414 To have it interpreted at the @code{Score} or @code{Staff} level use
418 \applyOutput #'Score #@var{function}
419 \applyOutput #'Staff #@var{function}
425 @node Modifying context plug-ins
426 @subsection Modifying context plug-ins
428 @c TODO Should this be Modifying engravers or Modifying contexts?
430 Notation contexts (like @code{Score} and @code{Staff}) not only
432 they also contain plug-ins called @q{engravers} that create notation
433 elements. For example, the @code{Voice} context contains a
434 @code{Note_head_engraver} and the @code{Staff} context contains a
435 @code{Key_signature_engraver}.
437 For a full a description of each plug-in, see
439 @rinternals{Engravers and Performers}.
442 Internals Reference @expansion{} Translation @expansion{} Engravers.
444 Every context described in
446 @rinternals{Contexts}
449 Internals Reference @expansion{} Translation @expansion{} Context.
451 lists the engravers used for that context.
454 It can be useful to shuffle around these plug-ins. This is done by
455 starting a new context with @code{\new} or @code{\context}, and
461 \new @var{context} \with @{
474 where the @dots{} should be the name of an engraver. Here is a simple
475 example which removes @code{Time_signature_engraver} and
476 @code{Clef_engraver} from a @code{Staff} context,
478 @lilypond[quote,relative=1,verbatim,fragment]
484 \remove "Time_signature_engraver"
485 \remove "Clef_engraver"
492 In the second staff there are no time signature or clef symbols. This
493 is a rather crude method of making objects disappear since it will affect
494 the entire staff. This method also influences the spacing, which may or
495 may not be desirable. More sophisticated methods of blanking objects
496 are shown in @rlearning{Visibility and color of objects}.
498 The next example shows a practical application. Bar lines and time
499 signatures are normally synchronized across the score. This is done
500 by the @code{Timing_translator} and @code{Default_bar_line_engraver}.
501 This plug-in keeps an administration of time signature, location
502 within the measure, etc. By moving these engraver from @code{Score} to
503 @code{Staff} context, we can have a score where each staff has its own
506 @cindex polymetric scores
507 @cindex Time signatures, multiple
509 @lilypond[quote,relative=1,ragged-right,verbatim,fragment]
511 \remove "Timing_translator"
512 \remove "Default_bar_line_engraver"
515 \consists "Timing_translator"
516 \consists "Default_bar_line_engraver"
522 \consists "Timing_translator"
523 \consists "Default_bar_line_engraver"
532 @node Changing context default settings
533 @subsection Changing context default settings
535 The adjustments of the previous subsections (
536 @ref{The set command}, @ref{Modifying context plug-ins}, and
537 @ref{Overview of modifying properties}) can also be entered
538 separately from the music in the @code{\layout} block,
547 \override Stem #'thickness = #4.0
548 \remove "Time_signature_engraver"
553 The @code{\Staff} command brings in the existing definition of the
554 staff context so that it can be modified.
559 \override Stem #'thickness = #4.0
560 \remove "Time_signature_engraver"
564 affect all staves in the score. Other contexts can be modified
567 The @code{\set} keyword is optional within the @code{\layout} block, so
583 It is not possible to collect context changes in a variable and apply
584 them to a @code{\context} definition by referring to that variable.
586 The @code{\RemoveEmptyStaffContext} will overwrite your current
587 @code{\Staff} settings. If you wish to change the defaults for a
588 staff which uses @code{\RemoveEmptyStaffContext}, you must do so
589 after calling @code{\RemoveEmptyStaffContext}, ie
594 \RemoveEmptyStaffContext
596 \override Stem #'thickness = #4.0
601 TODO: add \with in here.
605 @node Defining new contexts
606 @subsection Defining new contexts
608 Specific contexts, like @code{Staff} and @code{Voice}, are made of
609 simple building blocks. It is possible to create new types of
610 contexts with different combinations of engraver plug-ins.
612 The next example shows how to build a different type of
613 @code{Voice} context from scratch. It will be similar to
614 @code{Voice}, but only prints centered slash note heads. It can be used
615 to indicate improvisation in jazz pieces,
617 @lilypond[quote,ragged-right]
620 \type "Engraver_group"
621 \consists "Note_heads_engraver"
622 \consists "Text_engraver"
623 \consists Pitch_squash_engraver
624 squashedPosition = #0
625 \override NoteHead #'style = #'slash
626 \override Stem #'transparent = ##t
630 \accepts "ImproVoice"
634 a4 d8 bes8 \new ImproVoice { c4^"ad lib" c
635 c4 c^"undress" c_"while playing :)" c }
641 These settings are defined within a @code{\context} block inside a
642 @code{\layout} block,
652 In the following discussion, the example input shown should go in place
653 of the @dots{} in the previous fragment.
655 First it is necessary to define a name for the new context:
661 Since it is similar to the @code{Voice}, we want commands that work
662 on (existing) @code{Voice}s to remain working. This is achieved by
663 giving the new context an alias @code{Voice},
669 The context will print notes and instructive texts, so we need to add
670 the engravers which provide this functionality,
673 \consists Note_heads_engraver
674 \consists Text_engraver
677 but we only need this on the center line,
680 \consists Pitch_squash_engraver
681 squashedPosition = #0
684 The @rinternals{Pitch_squash_engraver} modifies note heads (created
685 by @rinternals{Note_heads_engraver}) and sets their vertical
686 position to the value of @code{squashedPosition}, in this case@tie{}@code{0},
689 The notes look like a slash, and have no stem,
692 \override NoteHead #'style = #'slash
693 \override Stem #'transparent = ##t
696 All these plug-ins have to cooperate, and this is achieved with a
697 special plug-in, which must be marked with the keyword @code{\type}.
698 This should always be @code{Engraver_group}.
701 \type "Engraver_group"
709 \type "Engraver_group"
710 \consists "Note_heads_engraver"
711 \consists "Text_engraver"
712 \consists Pitch_squash_engraver
713 squashedPosition = #0
714 \override NoteHead #'style = #'slash
715 \override Stem #'transparent = ##t
721 Contexts form hierarchies. We want to hang the @code{ImproVoice}
722 under @code{Staff}, just like normal @code{Voice}s. Therefore, we
723 modify the @code{Staff} definition with the @code{\accepts}
734 The opposite of @code{\accepts} is @code{\denies},
735 which is sometimes needed when reusing existing context definitions.
737 Putting both into a @code{\layout} block, like
747 \accepts "ImproVoice"
752 Then the output at the start of this subsection can be entered as
760 c c_"while playing :)"
767 @node Aligning contexts
768 @subsection Aligning contexts
770 New contexts may be aligned above or below existing contexts. This
771 could be useful in setting up a vocal staff (@rlearning{Vocal ensembles}) and
774 @c TODO Better example needed. Ref LM, and expand on it.
777 @findex alignAboveContext
778 @findex alignBelowContext
780 @lilypond[quote,ragged-right]
783 \relative c' \new Staff = "main" {
786 \new Staff \with {alignAboveContext=main} \ossia
794 @node Explaining the Internals Reference
795 @section Explaining the Internals Reference
799 * Navigating the program reference::
800 * Layout interfaces::
801 * Determining the grob property::
802 * Naming conventions::
805 @node Navigating the program reference
806 @subsection Navigating the program reference
808 @c TODO remove this (it's in the LM)
809 @c Replace with more factual directions
811 Suppose we want to move the fingering indication in the fragment
814 @lilypond[quote,fragment,relative=2,verbatim]
820 If you visit the documentation on fingering instructions (in
821 @ref{Fingering instructions}), you will notice:
826 Internals Reference: @rinternals{Fingering}.
831 @c outdated info; probably will delete.
833 This fragment points to two parts of the program reference: a page
834 on @code{FingeringEvent} and one on @code{Fingering}.
836 The page on @code{FingeringEvent} describes the properties of the music
837 expression for the input @code{-2}. The page contains many links
838 forward. For example, it says
841 Accepted by: @rinternals{Fingering_engraver},
845 That link brings us to the documentation for the Engraver, the
849 This engraver creates the following layout objects: @rinternals{Fingering}.
852 In other words, once the @code{FingeringEvent}s are interpreted, the
853 @code{Fingering_engraver} plug-in will process them.
857 @c I can't figure out what this is supposed to mean. -gp
859 The @code{Fingering_engraver} is also listed to create
860 @rinternals{Fingering} objects,
862 @c old info? it doesn't make any sense to me with our current docs.
864 second bit of information listed under @b{See also} in the Notation
869 The programmer's reference is available as an HTML document. It is
870 highly recommended that you read it in HTML form, either online or
871 by downloading the HTML documentation. This section will be much more
872 difficult to understand if you are using the
876 Follow the link to @rinternals{Fingering}. At the top of the
880 Fingering objects are created by: @rinternals{Fingering_engraver} and
881 @rinternals{New_fingering_engraver}.
884 By following related links inside the program reference, we can follow the
885 flow of information within the program:
889 @item @rinternals{Fingering}:
890 @rinternals{Fingering} objects are created by:
891 @rinternals{Fingering_engraver}
893 @item @rinternals{Fingering_engraver}:
894 Music types accepted: @rinternals{fingering-event}
896 @item @rinternals{fingering-event}:
897 Music event type @code{fingering-event} is in Music expressions named
898 @rinternals{FingeringEvent}
901 This path goes against the flow of information in the program: it
902 starts from the output, and ends at the input event. You could
903 also start at an input event, and read with the flow of
904 information, eventually ending up at the output object(s).
906 The program reference can also be browsed like a normal document. It
909 @rinternals{Music definitions},
912 @code{Music definitions}
914 on @rinternals{Translation}, and the @rinternals{Backend}. Every
915 chapter lists all the definitions used and all properties that may be
919 @node Layout interfaces
920 @subsection Layout interfaces
922 @cindex interface, layout
923 @cindex layout interface
926 The HTML page that we found in the previous section describes the
927 layout object called @rinternals{Fingering}. Such an object is a
928 symbol within the score. It has properties that store numbers (like
929 thicknesses and directions), but also pointers to related objects. A
930 layout object is also called a @emph{Grob}, which is short for Graphical
931 Object. For more details about Grobs, see @rinternals{grob-interface}.
933 The page for @code{Fingering} lists the definitions for the
934 @code{Fingering} object. For example, the page says
937 @code{padding} (dimension, in staff space):
943 which means that the number will be kept at a distance of at least 0.5
947 Each layout object may have several functions as a notational or
948 typographical element. For example, the Fingering object
949 has the following aspects
953 Its size is independent of the horizontal spacing, unlike slurs or beams.
956 It is a piece of text. Granted, it is usually a very short text.
959 That piece of text is typeset with a font, unlike slurs or beams.
962 Horizontally, the center of the symbol should be aligned to the
963 center of the note head.
966 Vertically, the symbol is placed next to the note and the staff.
969 The vertical position is also coordinated with other superscript
970 and subscript symbols.
973 Each of these aspects is captured in so-called @emph{interface}s,
974 which are listed on the @rinternals{Fingering} page at the bottom
977 This object supports the following interfaces:
978 @rinternals{item-interface},
979 @rinternals{self-alignment-interface},
980 @rinternals{side-position-interface}, @rinternals{text-interface},
981 @rinternals{text-script-interface}, @rinternals{font-interface},
982 @rinternals{finger-interface}, and @rinternals{grob-interface}.
985 Clicking any of the links will take you to the page of the respective
986 object interface. Each interface has a number of properties. Some of
987 them are not user-serviceable (@q{Internal properties}), but others
990 We have been talking of @emph{the} @code{Fingering} object, but actually it
991 does not amount to much. The initialization file (see
992 @rlearning{Other sources of information})
993 @file{scm/@/define@/-grobs@/.scm} shows the soul of the @q{object},
998 (avoid-slur . around)
1000 (staff-padding . 0.5)
1001 (self-alignment-X . 0)
1002 (self-alignment-Y . 0)
1003 (script-priority . 100)
1004 (stencil . ,ly:text-interface::print)
1005 (direction . ,ly:script-interface::calc-direction)
1006 (font-encoding . fetaNumber)
1007 (font-size . -5) ; don't overlap when next to heads.
1008 (meta . ((class . Item)
1009 (interfaces . (finger-interface
1011 text-script-interface
1013 side-position-interface
1014 self-alignment-interface
1015 item-interface))))))
1019 As you can see, the @code{Fingering} object is nothing more than a
1020 bunch of variable settings, and the webpage in the Internals Reference
1021 is directly generated from this definition.
1024 @node Determining the grob property
1025 @subsection Determining the grob property
1027 @c TODO remove this (it's in the LM)
1028 @c Replace with more factual directions
1030 Recall that we wanted to change the position of the @b{2} in
1032 @lilypond[quote,fragment,relative=2,verbatim]
1038 Since the @b{2} is vertically positioned next to its note, we have to
1039 meddle with the interface associated with this positioning. This is
1040 done using @code{side-position-interface}. The page for this interface
1044 @code{side-position-interface}
1046 Position a victim object (this one) next to other objects (the
1047 support). The property @code{direction} signifies where to put the
1048 victim object relative to the support (left or right, up or down?)
1053 Below this description, the variable @code{padding} is described as
1058 (dimension, in staff space)
1060 Add this much extra space between objects that are next to each other.
1064 By increasing the value of @code{padding}, we can move the
1065 fingering away from the note head. The following command inserts
1066 3 staff spaces of white
1067 between the note and the fingering:
1069 \once \override Voice.Fingering #'padding = #3
1072 Inserting this command before the Fingering object is created,
1073 i.e., before @code{c2}, yields the following result:
1075 @lilypond[quote,relative=2,fragment,verbatim]
1076 \once \override Voice.Fingering #'padding = #3
1083 In this case, the context for this tweak is @code{Voice}. This
1084 fact can also be deduced from the program reference, for the page for
1085 the @rinternals{Fingering_engraver} plug-in says
1088 Fingering_engraver is part of contexts: @dots{} @rinternals{Voice}
1092 @node Naming conventions
1093 @subsection Naming conventions
1095 Another thing that is needed, is an overview of the various naming
1098 scheme functions: lowercase-with-hyphens (incl. one-word
1100 scheme functions: ly:plus-scheme-style
1101 music events, music classes and music properties:
1103 Grob interfaces: scheme-style
1104 backend properties: scheme-style (but X and Y!)
1105 contexts (and MusicExpressions and grobs): Capitalized or
1107 context properties: lowercaseFollowedByCamelCase
1109 Capitalized_followed_by_lowercase_and_with_underscores
1111 Which of these are conventions and which are rules?
1112 Which are rules of the underlying language, and which are
1116 @node Modifying properties
1117 @section Modifying properties
1120 * Overview of modifying properties::
1122 * The override command::
1123 * set versus override::
1124 * The tweak command::
1128 @node Overview of modifying properties
1129 @subsection Overview of modifying properties
1131 Each context is responsible for creating certain types of graphical
1132 objects. The settings used for printing these objects are also stored by
1133 context. By changing these settings, the appearance of objects can be
1136 The syntax for this is
1139 \override @var{context}.@var{name} #'@var{property} = #@var{value}
1142 Here @var{name} is the name of a graphical object, like
1143 @code{Stem} or @code{NoteHead}, and @var{property} is an internal
1144 variable of the formatting system (@q{grob property} or @q{layout
1145 property}). The latter is a symbol, so it must be quoted. The
1146 subsection @ref{Modifying properties}, explains what to fill in
1147 for @var{name}, @var{property}, and @var{value}. Here we only
1148 discuss the functionality of this command.
1153 \override Staff.Stem #'thickness = #4.0
1157 makes stems thicker (the default is 1.3, with staff line thickness as a
1158 unit). Since the command specifies @code{Staff} as context, it only
1159 applies to the current staff. Other staves will keep their normal
1160 appearance. Here we see the command in action:
1162 @lilypond[quote,verbatim,relative=2,fragment]
1164 \override Staff.Stem #'thickness = #4.0
1170 The @code{\override} command changes the definition of the @code{Stem}
1171 within the current @code{Staff}. After the command is interpreted
1172 all stems are thickened.
1174 Analogous to @code{\set}, the @var{context} argument may be left out,
1175 causing the default context @code{Voice} to be used. Adding
1176 @code{\once} applies the change during one timestep only.
1178 @lilypond[quote,fragment,verbatim,relative=2]
1180 \once \override Stem #'thickness = #4.0
1185 The @code{\override} must be done before the object is
1186 started. Therefore, when altering @emph{Spanner} objects such as slurs
1187 or beams, the @code{\override} command must be executed at the moment
1188 when the object is created. In this example,
1190 @lilypond[quote,fragment,verbatim,relative=2]
1191 \override Slur #'thickness = #3.0
1193 \override Beam #'thickness = #0.6
1198 the slur is fatter but the beam is not. This is because the command for
1199 @code{Beam} comes after the Beam is started, so it has no effect.
1201 Analogous to @code{\unset}, the @code{\revert} command for a context
1202 undoes an @code{\override} command; like with @code{\unset}, it only
1203 affects settings that were made in the same context. In other words, the
1204 @code{\revert} in the next example does not do anything.
1207 \override Voice.Stem #'thickness = #4.0
1208 \revert Staff.Stem #'thickness
1211 Some tweakable options are called @q{subproperties} and reside inside
1212 properties. To tweak those, use commands of the form
1214 @c leave this as a long long
1216 \override @var{context}.@var{name} #'@var{property} #'@var{subproperty} = #@var{value}
1223 \override Stem #'details #'beamed-lengths = #'(4 4 3)
1229 Internals: @rinternals{OverrideProperty}, @rinternals{RevertProperty},
1230 @rinternals{PropertySet}, @rinternals{Backend}, and
1231 @rinternals{All layout objects}.
1236 The back-end is not very strict in type-checking object properties.
1237 Cyclic references in Scheme values for properties can cause hangs
1238 or crashes, or both.
1242 @node The set command
1243 @subsection The @code{\set} command
1247 @cindex changing properties
1249 Each context can have different @emph{properties}, variables contained
1250 in that context. They can be changed during the interpretation step.
1251 This is achieved by inserting the @code{\set} command in the music,
1254 \set @var{context}.@var{prop} = #@var{value}
1258 @lilypond[quote,verbatim,relative=2,fragment]
1260 \set Score.skipBars = ##t
1264 This command skips measures that have no notes. The result is that
1265 multi-rests are condensed. The value assigned is a Scheme object. In
1266 this case, it is @code{#t}, the boolean True value.
1268 If the @var{context} argument is left out, then the current bottom-most
1269 context (typically @code{ChordNames}, @code{Voice}, or
1270 @code{Lyrics}) is used. In this example,
1272 @lilypond[quote,verbatim,relative=2,fragment]
1274 \set autoBeaming = ##f
1279 the @var{context} argument to @code{\set} is left out, so automatic
1280 beaming is switched off in the current @rinternals{Voice}. Note that
1281 the bottom-most context does not always contain the property that you
1282 wish to change -- for example, attempting to set the @code{skipBars}
1283 property (of the bottom-most context, in this case @code{Voice}) will
1286 @lilypond[quote,verbatim,relative=2,fragment]
1292 Contexts are hierarchical, so if a bigger context was specified, for
1293 example @code{Staff}, then the change would also apply to all
1294 @code{Voice}s in the current stave. The change is applied
1295 @q{on-the-fly}, during the music, so that the setting only affects the
1296 second group of eighth notes.
1300 There is also an @code{\unset} command,
1302 \unset @var{context}.@var{prop}
1306 which removes the definition of @var{prop}. This command removes
1307 the definition only if it is set in @var{context}, so
1310 \set Staff.autoBeaming = ##f
1314 introduces a property setting at @code{Staff} level. The setting also
1315 applies to the current @code{Voice}. However,
1318 \unset Voice.autoBeaming
1322 does not have any effect. To cancel this setting, the @code{\unset}
1323 must be specified on the same level as the original @code{\set}. In
1324 other words, undoing the effect of @code{Staff.autoBeaming = ##f}
1327 \unset Staff.autoBeaming
1330 Like @code{\set}, the @var{context} argument does not have to be
1331 specified for a bottom context, so the two statements
1334 \set Voice.autoBeaming = ##t
1335 \set autoBeaming = ##t
1343 Settings that should only apply to a single time-step can be entered
1344 with @code{\once}, for example in
1346 @lilypond[quote,verbatim,relative=2,fragment]
1348 \once \set fontSize = #4.7
1353 the property @code{fontSize} is unset automatically after the second
1356 A full description of all available context properties is in the
1357 program reference, see
1359 @rinternals{Tunable context properties}.
1362 Translation @expansion{} Tunable context properties.
1367 @node The override command
1368 @subsection The @code{\override} command
1370 Commands which change output generally look like
1373 \override Voice.Stem #'thickness = #3.0
1377 To construct this tweak we must determine these bits of information:
1380 @item the context: here @code{Voice}.
1381 @item the layout object: here @code{Stem}.
1382 @item the layout property: here @code{thickness}.
1383 @item a sensible value: here @code{3.0}.
1386 Some tweakable options are called @q{subproperties} and reside inside
1387 properties. To tweak those, use commands in the form
1390 \override Stem #'details #'beamed-lengths = #'(4 4 3)
1393 @cindex internal documentation
1394 @cindex finding graphical objects
1395 @cindex graphical object descriptions
1398 @cindex internal documentation
1400 For many properties, regardless of the data type of the property, setting the
1401 property to false ( @code{##f} ) will result in turning it off, causing
1402 LilyPond to ignore that property entirely. This is particularly useful for
1403 turning off grob properties which may otherwise be causing problems.
1405 We demonstrate how to glean this information from the notation manual
1406 and the program reference.
1409 @node set versus override
1410 @subsection @code{\set} vs. @code{\override}
1412 We have seen two methods of changing properties: @code{\set} and
1413 @code{\override}. There are actually two different kinds of
1416 Contexts can have properties, which are usually named in
1417 @code{studlyCaps}. They mostly control the translation from
1418 music to notation, eg. @code{localKeySignature} (for determining
1419 whether to print accidentals), @code{measurePosition} (for
1420 determining when to print a bar line). Context properties can
1421 change value over time while interpreting a piece of music;
1422 @code{measurePosition} is an obvious example of
1423 this. Context properties are modified with @code{\set}.
1425 There is a special type of context property: the element
1426 description. These properties are named in @code{StudlyCaps}
1427 (starting with capital letters). They contain the
1428 @q{default settings} for said graphical object as an
1429 association list. See @file{scm/@/define@/-grobs@/.scm}
1430 to see what kind of settings there are. Element descriptions
1431 may be modified with @code{\override}.
1433 @code{\override} is actually a shorthand;
1436 \override @var{context}.@var{name} #'@var{property} = #@var{value}
1440 is more or less equivalent to
1442 @c leave this long line -gp
1444 \set @var{context}.@var{name} #'@var{property} = #(cons (cons '@var{property} @var{value}) <previous value of @var{context})
1447 The value of @code{context} (the alist) is used to initialize
1448 the properties of individual grobs. Grobs also have
1449 properties, named in Scheme style, with
1450 @code{dashed-words}. The values of grob properties change
1451 during the formatting process: formatting basically amounts
1452 to computing properties using callback functions.
1454 @code{fontSize} is a special property: it is equivalent to
1455 entering @code{\override ... #'font-size} for all pertinent
1456 objects. Since this is a common change, the special
1457 property (modified with @code{\set}) was created.
1460 @node The tweak command
1461 @subsection The @code{\tweak} command
1463 TODO: can't use \tweak in a variable
1467 In some cases, it is possible to take a short-cut for tuning graphical
1468 objects. For objects that result directly from a piece of the input,
1469 you can use the @code{\tweak} function, for example
1471 @lilypond[relative=2,fragment,verbatim,ragged-right]
1474 \tweak #'color #red d
1476 \tweak #'duration-log #1 a
1477 >4-\tweak #'padding #10 -.
1480 As you can see, properties are set in the objects directly,
1481 without mentioning the grob name or context where this should be
1484 This technique only works for objects that are directly connected to
1485 an @rinternals{Event} from the input, for example
1488 @item note heads, caused by chord-pitch (i.e., notes inside a chord)
1489 @item articulation signs, caused by articulation instructions
1492 It notably does not work for stems and accidentals (these are caused
1493 by note heads, not by music events) or clefs (these are not caused by
1494 music inputs, but rather by the change of a property value).
1496 There are very few objects which are @emph{directly} connected to
1497 output. A normal note (like @code{c4}) is not directly connected
1501 \tweak #'color #red c4
1505 does not change color. See @ref{Displaying music expressions}, for
1509 @node Useful concepts and properties
1510 @section Useful concepts and properties
1515 * Direction and placement::
1516 * Distances and measurements::
1521 @subsection Input modes
1523 The way in which the notation contained within an input file is
1524 interpreted is determined by the current input mode.
1528 This is activated with the @code{\chordmode} command, and causes
1529 input to be interpreted with the syntax of chord notation, see
1530 @ref{Chord notation}. Chords are rendered as notes on a staff.
1532 Chord mode is also activated with the @code{\chords} command.
1533 This also creates a new @code{ChordNames} context and
1534 causes the following input to be interpreted with the syntax of
1535 chord notation and rendered as chord names in the @code{ChordNames}
1536 context, see @ref{Printing chord names}.
1540 This is activated with the @code{\drummode} command, and causes
1541 input to be interpreted with the syntax of drum notation, see
1542 @ref{Basic percussion notation}.
1544 Drum mode is also activated with the @code{\drums} command.
1545 This also creates a new @code{DrumStaff} context and causes the
1546 following input to be interpreted with the syntax of drum notation
1547 and rendered as drum symbols on a drum staff, see @ref{Basic
1548 percussion notation}.
1550 @strong{Figure mode}
1552 This is activated with the @code{\figuremode} command, and causes
1553 input to be interpreted with the syntax of figured bass, see
1554 @ref{Entering figured bass}.
1556 Figure mode is also activated with the @code{\figures} command.
1557 This also creates a new @code{FiguredBass} context and causes the
1558 following input to be interpreted with the figured bass syntax
1559 and rendered as figured bass symbols in the @code{FiguredBass}
1560 context, see @ref{Introduction to figured bass}.
1562 @strong{Fret and tab modes}
1564 There are no special input modes for entering fret and tab symbols.
1566 To create tab diagrams, enter notes or chords in note mode and
1567 render them in a @code{TabStaff} context, see
1568 @ref{Default tablatures}.
1570 To create fret diagrams above a staff, you have two choices.
1571 You can either use the @code{FretBoards} context (see
1572 @ref{Automatic fret diagrams} or you can enter them as a markup
1573 above the notes using the @code{\fret-diagram} command (see
1574 @ref{Fret diagram markups}).
1576 @strong{Lyrics mode}
1578 This is activated with the @code{\lyricmode} command, and causes
1579 input to be interpreted as lyric syllables with optional durations
1580 and associated lyric modifiers, see @ref{Vocal music}.
1582 Lyric mode is also activated with the @code{\addlyrics} command.
1583 This also creates a new @code{Lyrics} context and an implicit
1584 @code{\lyricsto} command which associates the following lyrics
1585 with the preceding music.
1587 @strong{Markup mode}
1589 This is activated with the @code{\markup} command, and causes
1590 input to be interpreted with the syntax of markup, see
1591 @ref{Text markup commands}.
1593 @c silly work-around for texinfo broken-ness
1594 @c (@strong{Note...} causes a spurious cross-reference in Info)
1597 This is the default mode or it may be activated with the
1598 @code{\notemode} command. Input is interpreted as pitches,
1599 durations, markup, etc and typeset as musical notation on a staff.
1601 It is not normally necessary to specify note mode explicitly, but
1602 it may be useful to do so in certain situations, for example if you
1603 are in lyric mode, chord mode or any other mode and want to insert
1604 something that only can be done with note mode syntax.
1606 For example, to indicate dynamic markings for the verses of a
1607 choral pieces it is necessary to enter note mode to interpret
1610 @lilypond[verbatim,relative=2,quote]
1613 \notemode{\set stanza = \markup{ \dynamic f 1. } }
1617 \notemode{\set stanza = \markup{ \dynamic p 2. } }
1624 @node Direction and placement
1625 @subsection Direction and placement
1627 In typesetting music the direction and placement of many items is
1628 a matter of choice. For example, the stems of notes can
1629 be directed up or down; lyrics, dynamics, and other expressive
1630 marks may be placed above or below the staff; text may be aligned
1631 left, right or center; etc. Most of these choices may be left to
1632 be determined automatically by LilyPond, but in some cases it may
1633 be desirable to force a particular direction or placement.
1635 @strong{Default actions}
1637 By default some directions are always up or always down (e.g.
1638 dynamics or fermata), while other things can alternate between
1639 up or down based on the stem direction (like slurs or accents).
1641 @c TODO Add table showing these
1643 @strong{Context layout}
1645 Contexts are positioned in a system from top to bottom in the
1646 order in which they are encountered. Note, however, that a
1647 context will be created implicitly if a command is encountered
1648 when there is no suitable context available to contain it.
1650 @c TODO Add example ?
1652 The default order in which contexts are laid out can be changed,
1653 see @ref{Aligning contexts}
1655 @strong{Articulation direction indicators}
1657 When adding articulations to notes the direction indicator,
1658 @code{^} (meaning @qq{up}), @code{_} (meaning @qq{down}) or
1659 @code{-} (meaning @qq{use default direction}), can usually be
1660 omitted, in which case @code{-} is assumed. But a direction
1661 indicator is @strong{always} required before
1664 @item @code{\tweak} commands
1665 @item @code{\markup} commands
1666 @item @code{\tag} commands
1667 @item string markups, e.g. -"string"
1668 @item fingering instructions, e.g. @code{-1}
1669 @item articulation shortcuts, e.g. @code{-.}, @code{->}, @code{--}
1672 @strong{The direction property}
1674 The position or direction of many layout objects is controlled
1675 by the @code{direction} property.
1677 The value of the @code{direction} property may be
1678 set to @code{1}, meaning @qq{up} or @qq{above}, or to @code{-1},
1679 meaning @qq{down} or @qq{below}. The symbols @code{UP} and
1680 @code{DOWN} may be used instead of @code{1} and @code{-1}
1681 respectively. The default direction may be specified by setting
1682 @code{direction} to @code{0} or @code{CENTER}. Alternatively,
1683 in many cases predefined commands
1684 exist to specify the direction. These are all of the form
1687 @code{\xxxUp}, @code{xxxDown}, @code{xxxNeutral}
1690 where @code{xxxNeutral} means @qq{use the default direction}.
1691 See @rlearning{Within-staff objects}.
1693 In a few cases, arpeggio being the only common example, the value
1694 of the @code{direction} property specifies whether the object
1695 is to be placed to the right or left of the parent object. In
1696 this case @code{-1} or @code{LEFT} means @qq{to the left} and
1697 @code{1} or @code{RIGHT} means @qq{to the right}. @code{0}
1698 or @code{CENTER} means @qq{use the default} direction, as before.
1701 These all have side-axis set to #X
1702 AmbitusAccidental - direction has no effect
1704 StanzaNumber - not tried
1705 TrillPitchAccidental - not tried
1706 TrillPitchGroup - not tried
1711 @node Distances and measurements
1712 @subsection Distances and measurements
1714 DISCUSS after working on other sections.
1716 TODO: staff spaces. Maybe move into tweaks?
1720 @subsection Spanners
1722 Many objects of musical notation extend over several notes or even
1723 several bars. Examples are crescendi, trills, tuplet brackets, and
1724 volta repeat brackets. Such objects are called @qq{spanners}, and
1725 have special properties to control their appearance and behaviour.
1726 Some of these properties are common to all spanners; others are
1727 restricted to a sub-set of the spanners.
1729 @node Common properties
1730 @section Common properties
1733 * Controlling visibility of objects::
1735 * Rotating objects::
1736 * Aligning objects::
1739 @node Controlling visibility of objects
1740 @subsection Controlling visibility of objects
1742 @cindex objects, visibility of
1743 @cindex grobs, visibility of
1744 @cindex visibility of objects
1746 There are four main ways in which the visibility of layout objects
1747 can be controlled: their stencil can be removed, they can be made
1748 transparent, they can be colored white, or their
1749 @code{break-visibility} property can be overridden. The first
1750 three apply to all layout objects; the last to just a few -- the
1751 @emph{breakable} objects. The Learning Manual introduces these
1752 four techniques, see @rlearning{Visibility and color of objects}.
1754 There are also a few other techniques which are specific to
1755 certain layout objects. These are covered under Special
1759 * Removing the stencil::
1760 * Making objects transparent::
1761 * Painting objects white::
1762 * Using break-visibility::
1763 * Special considerations::
1767 @node Removing the stencil
1768 @unnumberedsubsubsec Removing the stencil
1770 @cindex stencil, removing
1772 Every layout object has a stencil property. By default this is set
1773 to the specific function which draws that object. If this property
1774 is overridden to @code{#f} no function will be called and the object
1775 will not be drawn. The default action can be recovered with
1778 @lilypond[quote,verbatim,relative=1]
1780 \override Score.BarLine #'stencil = ##f
1782 \revert Score.BarLine #'stencil
1786 @node Making objects transparent
1787 @unnumberedsubsubsec Making objects transparent
1789 @cindex transparent, making objects
1791 Every layout object has a transparent property which by default is
1792 set to @code{#f}. If set to @code{#t} the object still occupies
1793 space but is made invisible.
1795 @lilypond[quote,verbatim,relative=2]
1797 \once \override NoteHead #'transparent = ##t
1801 @node Painting objects white
1802 @unnumberedsubsubsec Painting objects white
1804 @cindex objects, coloring
1805 @cindex coloring objects
1807 @cindex printing order
1808 @cindex overwriting objects
1809 @cindex objects, overwriting
1810 @cindex grobs, overwriting
1812 Every layout object has a color property which by default is set
1813 to @code{black}. If this is overridden to @code{white} the object
1814 will be indistinguishable from the white background. However,
1815 if the object crosses other objects the color of the crossing
1816 points will be determined by the order in which they are drawn,
1817 and this may leave a ghostly image of the white object, as shown
1820 @lilypond[quote,verbatim,relative=2]
1821 \override Staff.Clef #'color = #white
1825 This may be avoided by changing the order of printing the objects.
1826 All layout objects have a @code{layer} property which should be set
1827 to an integer. Objects with the lowest value of @code{layer} are
1828 drawn first, then objects with progressively higher values are drawn,
1829 so objects with higher values overwrite objects with lower values.
1830 By default most objects are assigned a @code{layer} value of
1831 @code{1}, although a few objects, including @code{StaffSymbol} and
1832 @code{BarLine}, are assigned a value of @code{0}. The order of
1833 printing objects with the same value of @code{layer} is indeterminate.
1835 In the example above the white clef, with a default @code{layer}
1836 value of @code{1}, is drawn after the staff lines (default
1837 @code{layer} value @code{0}), so overwriting them. To change this,
1838 the @code{Clef} object must be given in a lower value of
1839 @code{layer}, say @code{-1}, so that it is drawn earlier:
1841 @lilypond[quote,verbatim,relative=2]
1842 \override Staff.Clef #'color = #white
1843 \override Staff.Clef #'layer = #-1
1847 @node Using break-visibility
1848 @unnumberedsubsubsec Using break-visibility
1850 @c TODO Add making other objects breakable
1852 @cindex break-visibility
1854 Most layout objects are printed only once, but some like
1855 bar lines, clefs, time signatures and key signatures, may need
1856 to be printed twice when a line break occurs -- once at the end
1857 of the line and again at the start of the next line. Such
1858 objects are called @emph{breakable}, and have a property, the
1859 @code{break-visibility} property to control their visibility
1860 at the three positions in which they may appear -- at the
1861 start of a line, within a line if they are changed, and at the
1862 end of a line if a change takes place there.
1864 For example, the time signature
1865 by default will be printed at the start of the first line, but
1866 nowhere else unless it changes, when it will be printed at the
1867 point at which the change occurs. If this change occurs at the
1868 end of a line the new time signature will be printed at the start
1869 of the next line and a cautionary time signature will be printed
1870 at the end of the previous line as well.
1872 This behaviour is controlled by the @code{break-visibility}
1873 property, which is explained in
1874 @c Leave this ref on a newline - formats incorrectly otherwise -td
1875 @rlearning{Visibility and color of objects}. This property takes
1876 a vector of three booleans which, in order, determine whether the
1877 object is printed at the end of, within the body of, or at the
1878 beginning of a line. Or to be more precise, before a line break,
1879 where there is no line break, or after a line break.
1881 Alternatively, seven of the eight combinations may be specified
1882 by pre-defined functions, defined in @file{scm/output-lib.scm},
1883 where the last three columns indicate whether the layout objects
1884 will be visible in the positions shown at the head of the columns:
1886 @multitable @columnfractions .40 .15 .1 .1 .1
1887 @c TODO check these more carefully
1888 @headitem Function @tab Vector @tab Before @tab At no @tab After
1889 @headitem form @tab form @tab break @tab break @tab break
1891 @item @code{all-invisible} @tab @code{'#(#f #f #f)} @ @ @tab no @tab no @tab no
1892 @item @code{begin-of-line-visible} @tab @code{'#(#f #f #t)} @tab no @tab no @tab yes
1893 @item @code{end-of-line-visible} @tab @code{'#(#t #f #f)} @tab yes @tab no @tab no
1894 @item @code{all-visible} @tab @code{'#(#t #t #t)} @tab yes @tab yes @tab yes
1895 @c The center-visible function is not defined
1896 @c @item @code{center-visible} @tab @code{'#(#f #t #f)} @tab no @tab yes @tab no
1897 @item @code{begin-of-line-invisible} @tab @code{'#(#t #t #f)} @tab yes @tab yes @tab no
1898 @item @code{end-of-line-invisible} @tab @code{'#(#f #t #t)} @tab no @tab yes @tab yes
1899 @item @code{center-invisible} @tab @code{'#(#t #f #t)} @tab yes @tab no @tab yes
1902 The @code{center-visible} function is not pre-defined.
1904 The default settings of @code{break-visibility} depend on the
1905 layout object. The following table shows all the layout objects
1906 of interest which are affected by @code{break-visibility} and the
1907 default setting of this property:
1909 @multitable @columnfractions .3 .3 .4
1911 @headitem Layout object @tab Usual context @tab Default setting
1913 @c omit Ambitus as it appears not to be affected by break-visibility -td
1914 @c @item @code{Ambitus} @tab as specified @tab @code{begin-of-line-visible}
1915 @item @code{BarLine} @tab @code{Score} @tab calculated
1916 @item @code{BarNumber} @tab @code{Score} @tab @code{begin-of-line-visible}
1917 @c omit the following item until it can be explained -td
1918 @c @item @code{BreakAlignGroup} @tab @code{Score} @tab calculated
1919 @item @code{BreathingSign} @tab @code{Voice} @tab @code{begin-of-line-invisible}
1920 @item @code{Clef} @tab @code{Staff} @tab @code{begin-of-line-visible}
1921 @item @code{Custos} @tab @code{Staff} @tab @code{end-of-line-visible}
1922 @item @code{DoublePercentRepeat} @tab @code{Voice} @tab @code{begin-of-line-invisible}
1923 @c omit KeyCancellation until it can be explained -td
1924 @c @item @code{KeyCancellation} @tab ?? @tab @code{begin-of-line-invisible}
1925 @item @code{KeySignature} @tab @code{Staff} @tab @code{begin-of-line-visible}
1926 @c omit LeftEdge until it can be explained -td
1927 @c @item @code{LeftEdge} @tab @code{Score} @tab @code{center-invisible}
1928 @item @code{OctavateEight} @tab @code{Staff} @tab @code{begin-of-line-visible}
1929 @item @code{RehearsalMark} @tab @code{Score} @tab @code{end-of-line-invisible}
1930 @item @code{TimeSignature} @tab @code{Staff} @tab @code{all-visible}
1934 The example below shows the use of the vector form to control the
1935 visibility of barlines:
1937 @lilypond[quote,verbatim,relative=1,ragged-right]
1940 % Remove bar line at the end of the current line
1941 \once \override Score.BarLine #'break-visibility = #'#(#f #t #t)
1947 Although all three components of the vector used to override
1948 @code{break-visibility} must be present, not all of them are
1949 effective with every layout object, and some combinations may
1950 even give errors. The following limitations apply:
1953 @item Bar lines cannot be printed at start of line.
1954 @item A bar number cannot be printed at the start of the first
1955 line unless it is set to be different from 1.
1956 @item Clef -- see below
1957 @item Double percent repeats are either all printed or all
1958 suppressed. Use begin-of line-invisible to print and
1959 all-invisible to suppress.
1960 @item Key signature -- see below
1961 @item OctavateEight -- see below
1964 @node Special considerations
1965 @unnumberedsubsubsec Special considerations
1967 @strong{@emph{Visibility following explicit changes}}
1969 @cindex key signature, visibility following explicit change
1970 @cindex explicitKeySignatureVisibility
1971 @cindex clef, visibility following explicit change
1972 @cindex explicitClefVisibility
1974 The @code{break-visibility} property controls the visibility of
1975 key signatures and changes of clef only at the start of lines,
1976 i.e. after a break. It has no effect on the visibility of the
1977 key signature or clef following an explicit key change or an
1978 explicit clef change within or at the end of a line. In the
1979 following example the key signature following the explicit change
1980 to B-flat major is still visible, even though @code{all-invisible}
1983 @lilypond[quote,verbatim,relative=1,ragged-right]
1986 % Try to remove all key signatures
1987 \override Staff.KeySignature #'break-visibility = #all-invisible
1995 The visibility of such explicit key signature and clef changes is
1996 controlled by the @code{explicitKeySignatureVisibility} and
1997 @code{explicitClefVisibility} properties. These are the equivalent
1998 of the @code{break-visibility} property and both take a vector of
1999 three booleans or the predefined functions listed above, exactly like
2000 @code{break-visibility}. Both are properties of the Staff context,
2001 not the layout objects themselves, and so they are set using the
2002 @code{\set} command. Both are set by default to @code{all-visible}.
2003 These properties control only the visibility of key signatures and
2004 clefs resulting from explicit changes and do not affect key
2005 signatures and clefs at the beginning of lines;
2006 @code{break-visibility} must still be overridden in the appropriate
2007 object to remove these.
2009 @lilypond[quote,verbatim,relative=1,ragged-right]
2012 \set Staff.explicitKeySignatureVisibility = #all-invisible
2013 \override Staff.KeySignature #'break-visibility = #all-invisible
2020 @strong{@emph{Visibility of cautionary accidentals}}
2022 To remove the cautionary accidentals printed at an explicit key
2023 change, set the Staff context property @code{printKeyCancellation}
2026 @lilypond[quote,verbatim,relative=1,ragged-right]
2029 \set Staff.explicitKeySignatureVisibility = #all-invisible
2030 \set Staff.printKeyCancellation = ##f
2031 \override Staff.KeySignature #'break-visibility = #all-invisible
2038 With these overrides only the accidentals before the notes remain
2039 to indicate the change of key.
2041 @c TODO Add visibility of cautionary accidentals before notes
2043 @strong{@emph{Automatic bars}}
2045 @cindex automaticBars
2046 @cindex bar lines, suppressing
2048 As a special case, the printing of bar lines can also be turned off
2049 by setting the @code{automaticBars} property in the Score context.
2050 If set to @code{#f}, bar lines will not be printed automatically;
2051 they must be explicitly created with a @code{\bar} command. Unlike
2052 the @code{\cadenzaOn} predefined command, measures are still counted.
2053 Bar generation will resume according to that count if this property
2054 is later set to @code{#t}. When set to @code{#f}, line breaks can
2055 occur only at explicit @code{\bar} commands.
2059 @strong{@emph{Octavated clefs}}
2061 @cindex octavated clefs, visibility of
2062 @cindex visibility of octavated clefs
2063 @cindex clefs, visibility of octavation
2065 The small octavation symbol on octavated clefs is produced by the
2066 @code{OctavateEight} layout object. Its visibility is controlled
2067 independently from that of the @code{Clef} object, so it is
2068 necessary to apply any required @code{break-visibility} overrides
2069 to both the @code{Clef} and the @code{OctavateEight} layout objects
2070 to fully suppress such clef symbols at the start of each line.
2072 For explicit clef changes, the @code{explicitClefVisibility}
2073 property controls both the clef symbol and any octavation symbol
2079 @rlearning{Visibility and color of objects}
2083 @subsection Line styles
2085 @c TODO: split the following explanations between expressive marks and
2086 @c text-related stuff. Perhaps create a new subsection named
2087 @c "Spanner limits", "Spanner boundaries"? -vv
2089 Some performance indications, e.g., @i{rallentando} and
2090 @i{accelerando} and @i{trills} are written as text and are
2091 extended over many measures with lines, sometimes dotted or wavy.
2093 These all use the same routines as the glissando for drawing the
2094 texts and the lines, and tuning their behavior is therefore also
2095 done in the same way. It is done with a spanner, and the routine
2096 responsible for drawing the spanners is
2097 @code{ly:line-interface::print}. This routine determines the
2098 exact location of the two @i{span points} and draws a line in
2099 between, in the style requested.
2101 Here is an example of the different line styles available, and how
2104 @lilypond[relative=2,ragged-right,verbatim,fragment]
2106 \once \override Glissando #'style = #'dashed-line
2108 \override Glissando #'style = #'dotted-line
2110 \override Glissando #'style = #'zigzag
2112 \override Glissando #'style = #'trill
2116 The information that determines the end-points is computed
2117 on-the-fly for every graphic object, but it is possible to
2120 @lilypond[relative=2,ragged-right,verbatim,fragment]
2122 \once \override Glissando #'bound-details #'right #'Y = #-2
2126 The @code{Glissando} object, like any other using the
2127 @code{ly:line-interface::print} routine, carries a nested
2128 association list. In the above statement, the value for @code{Y}
2129 is set to @code{-2} for the association list corresponding to the
2130 right end point. Of course, it is also possible to adjust the
2131 left side with @code{left} instead of @code{right}.
2133 If @code{Y} is not set, the value is computed from the vertical
2134 position of right attachment point of the spanner.
2136 In case of a line break, the values for the span-points are
2137 extended with contents of the @code{left-broken} and
2138 @code{right-broken} sublists, for example
2140 @lilypond[relative=2,ragged-right,verbatim,fragment]
2141 \override Glissando #'breakable = ##T
2142 \override Glissando #'bound-details #'right-broken #'Y = #-3
2143 c1 \glissando \break
2147 The following properties can be used for the
2151 This sets the Y-coordinate of the end point, in staff space. By
2152 default, it is the center of the bound object, so for a glissando
2153 it points to the vertical center of the note head.
2155 For horizontal spanners, such as text spanner and trill spanners,
2156 it is hardcoded to 0.
2159 This determines where the line starts and ends in X-direction,
2160 relative to the bound object. So, a value of @code{-1} (or
2161 @code{LEFT}) makes the line start/end at the left side of the note
2162 head it is attached to.
2165 This is the absolute coordinate of the end point. It is usually
2166 computed on the fly, and there is little use in overriding it.
2169 Line spanners may have symbols at the beginning or end, which is
2170 contained in this sub-property. This is for internal use, it is
2171 recommended to use @code{text}.
2174 This is a markup that is evaluated to yield stencil. It is used
2175 to put @i{cresc.} and @i{tr} on horizontal spanners.
2177 @lilypond[quote,ragged-right,fragment,relative=2,verbatim]
2178 \override TextSpanner #'bound-details #'left #'text
2179 = \markup { \small \bold Slower }
2180 c2\startTextSpan b c a\stopTextSpan
2183 @item stencil-align-dir-y
2184 @item stencil-offset
2185 Without setting this, the stencil is simply put there at the
2186 end-point, as defined by the @code{X} and @code{Y} sub properties.
2187 Setting either @code{stencil-align-dir-y} or @code{stencil-offset}
2188 will move the symbol at the edge relative to the end point of the
2191 @lilypond[relative=1,fragment,verbatim]
2192 \override TextSpanner #'bound-details
2193 #'left #'stencil-align-dir-y = #DOWN
2194 \override TextSpanner #'bound-details
2195 #'right #'stencil-align-dir-y = #UP
2197 \override TextSpanner #'bound-details
2198 #'left #'text = #"gggg"
2199 \override TextSpanner #'bound-details
2200 #'right #'text = #"hhhh"
2201 c4^\startTextSpan c c c \stopTextSpan
2205 Setting this sub property to @code{#t} produce an arrowhead at the
2209 This sub property controls the space between the specified
2210 end-point of the line and the actual end. Without padding, a
2211 glissando would start and end in the center of each note head.
2215 @c TODO: Move to 5.4.4
2217 The music function \endSpanners terminates spanners and hairpins
2218 after exactly one note.
2220 @lilypond[verbatim,quote,ragged-right,relative=2,fragment]
2222 c2 \startTextSpan c2
2226 When using \endSpanners it is not necessary to close
2227 \startTextSpan with \stopTextSpan, nor is it necessary to close
2234 Internals Reference: @rinternals{TextSpanner},
2235 @rinternals{Glissando}, @rinternals{VoiceFollower},
2236 @rinternals{TrillSpanner},
2237 @rinternals{line-spanner-interface}.
2240 @node Rotating objects
2241 @subsection Rotating objects
2243 Both layout objects and elements of markup text can be rotated by
2244 any angle about any point, but the method of doing so differs.
2247 * Rotating layout objects::
2251 @node Rotating layout objects
2252 @unnumberedsubsubsec Rotating layout objects
2254 @cindex rotating objects
2255 @cindex objects, rotating
2257 All layout objects which support the @code{grob-interface} can be
2258 rotated by setting their @code{rotation} property. This takes a
2259 list of three items: the angle of rotation counter-clockwise,
2260 and the x and y coordinates of the point relative to the object's
2261 reference point about which the rotation is to be performed. The
2262 angle of rotation is specified in degrees and the coordinates in
2265 The angle of rotation and the coordinates of the rotation point must
2266 be determined by trial and error.
2268 @cindex hairpins, angled
2269 @cindex angled hairpins
2271 There are only a few situations where the rotation of layout
2272 objects is useful; the following example shows one situation where
2275 @lilypond[quote,verbatim,relative=1]
2277 \override Hairpin #'rotation = #'(20 -1 0)
2281 @node Rotating markup
2282 @unnumberedsubsubsec Rotating markup
2284 All markup text can be rotated to lie at any angle by prefixing it
2285 with the @code{\rotate} command. The command takes two arguments:
2286 the angle of rotation in degrees counter-clockwise and the text to
2287 be rotated. The extents of the text are not rotated: they take
2288 their values from the extremes of the x and y coordinates of the
2289 rotated text. In the following example the
2290 @code{outside-staff-priority} property for text is set to @code{#f}
2291 to disable the automatic collision avoidance, which would push some
2292 of the text too high.
2294 @lilypond[quote,verbatim,relative=1]
2295 \override TextScript #'outside-staff-priority = ##f
2296 g4^\markup { \rotate #30 "a G" }
2297 b^\markup { \rotate #30 "a B" }
2298 des^\markup { \rotate #30 "a D-Flat" }
2299 fis^\markup { \rotate #30 "an F-Sharp" }
2303 @node Aligning objects
2304 @subsection Aligning objects
2306 @c FIXME Write this section
2309 @node Advanced tweaks
2310 @section Advanced tweaks
2313 * Vertical grouping of grobs::
2314 * Modifying ends of spanners::
2315 * Modifying stencils::
2316 * Modifying shapes::
2322 @node Vertical grouping of grobs
2323 @subsection Vertical grouping of grobs
2325 @c FIXME Expand this section
2327 The VerticalAlignment and VerticalAxisGroup grobs work together.
2328 VerticalAxisGroup groups together different grobs like Staff, Lyrics,
2329 etc. VerticalAlignment then vertically aligns the different grobs
2330 grouped together by VerticalAxisGroup. There is usually only one
2331 VerticalAlignment per score but every Staff, Lyrics, etc. has its own
2335 @node Modifying ends of spanners
2336 @subsection Modifying ends of spanners
2338 @c FIXME Write this section
2339 @c See earlier material in Line styles
2341 @node Modifying stencils
2342 @subsection Modifying stencils
2344 All layout objects have a @code{stencil} property which is part of
2345 the @code{grob-interface}. By default, this property is usually
2346 set to a function specific to the object that is tailor-made to
2347 render the symbol which represents it in the output. For example,
2348 the standard setting for the @code{stencil} property of the
2349 @code{MultiMeasureRest} object is @code{ly:multi-measure-rest::print}.
2351 The standard symbol for any object can be replaced by modifying the
2352 @code{stencil} property to reference a different, specially-written,
2353 procedure. This requires a high level of knowledge of the internal
2354 workings of LilyPond, but there is an easier way which can often
2355 produce adequate results.
2357 This is to set the @code{stencil} property to the procedure which
2358 prints text -- @code{ly:text-interface::print} -- and to add a
2359 @code{text} property to the object which is set to contain the
2360 markup text which produces the required symbol. Due to the
2361 flexibility of markup, much can be achieved -- see in particular
2362 @ref{Graphic notation inside markup}.
2364 The following example demonstrates this by changing the note head
2365 symbol to a cross within a circle.
2367 @lilypond[verbatim,quote]
2369 \once \override NoteHead #'stencil = #ly:text-interface::print
2370 \once \override NoteHead #'text = \markup {
2372 \halign #-0.7 \draw-circle #0.85 #0.2 ##f
2373 \musicglyph #"noteheads.s2cross"
2381 Any of the glyphs in the feta Font can be supplied to the
2382 @code{\musicglyph} markup command -- see @ref{The Feta font}.
2384 @c TODO Add inserting eps files or ref to later
2386 @c TODO Add inserting Postscript or ref to later
2391 @ref{Graphic notation inside markup},
2392 @ref{Formatting text},
2393 @ref{Text markup commands},
2394 @ref{The Feta font}.
2397 @node Modifying shapes
2398 @subsection Modifying shapes
2401 * Modifying ties and slurs::
2404 @node Modifying ties and slurs
2405 @unnumberedsubsubsec Modifying ties and slurs
2407 Ties, slurs and phrasing slurs are drawn as third-order Bézier
2408 curves. If the shape of the tie or slur which is calculated
2409 automatically is not optimum, the shape may be modified manually by
2410 explicitly specifying the four control points required to define
2411 a third-order Bézier curve.
2413 Third-order or cubic Bézier curves are defined by four control
2414 points. The first and fourth control points are precisely the
2415 starting and ending points of the curve. The intermediate two
2416 control points define the shape. Animations showing how the curve
2417 is drawn can be found on the web, but the following description
2418 may be helpful. The curve starts from the first control point
2419 heading directly towards the second, gradually bending over to
2420 head towards the third and continuing to bend over to head towards
2421 the fourth, arriving there travelling directly from the third
2422 control point. The curve is entirely contained in the
2423 quadrilateral defined by the four control points.
2425 Here is an example of a case where the tie is not optimum, and
2426 where @code{\tieDown} would not help.
2428 @lilypond[verbatim,quote,relative=1]
2432 { r4 <g c,> <g c,> <g c,> }
2436 One way of improving this tie is to manually modify its control
2439 The coordinates of the Bézier control points are specified in units
2440 of staff-spaces. The X@tie{}coordinate is relative to the reference
2441 point of the note to which the tie or slur is attached, and the
2442 Y@tie{}coordinate is relative to the staff center line. The
2443 coordinates are entered as a list of four pairs of decimal numbers
2444 (reals). One approach is to estimate the coordinates of the two
2445 end points, and then guess the two intermediate points. The optimum
2446 values are then found by trial and error.
2448 It is useful to remember that a symmetric curve requires symmetric
2449 control points, and that Bézier curves have the useful property that
2450 transformations of the curve such as translation, rotation and
2451 scaling can be achieved by applying the same transformation to the
2452 curve's control points.
2454 For the example above the following override gives a satisfactory
2457 @lilypond[verbatim,quote,relative=1]
2460 #'control-points = #'((1 . -1) (3 . 0.6) (12.5 . 0.6) (14.5 . -1))
2463 { r4 <g c,> <g c,> <g c,>4 }
2469 It is not possible to modify shapes of ties or slurs by changing
2470 the @code{control-points} property if there are more than one at
2471 the same musical moment, not even by using the @code{\tweak}
2476 @node Discussion of specific tweaks
2477 @section Discussion of specific tweaks
2480 * old Contexts explained::
2484 @node old Contexts explained
2485 @subsection old Contexts explained
2487 @c FIXME Delete this section? It is in LM
2488 @c Or leave heading and go on from LM?
2490 When music is printed, a lot of notational elements must be added to the
2491 output. For example, compare the input and output of the following example:
2493 @lilypond[quote,verbatim,relative=2,fragment]
2497 The input is rather sparse, but in the output, bar lines, accidentals,
2498 clef, and time signature are added. LilyPond @emph{interprets} the
2499 input. During this step, the musical information is inspected in time
2500 order, similar to reading a score from left to right. While reading
2501 the input, the program remembers where measure boundaries are, and which
2502 pitches require explicit accidentals. This information can be presented on
2503 several levels. For example, the effect of an accidental is limited
2504 to a single staff, while a bar line must be synchronized across the
2507 Within LilyPond, these rules and bits of information are grouped in
2508 @emph{Contexts}. Some examples of contexts are @code{Voice},
2509 @code{Staff}, and @code{Score}. They are hierarchical, for
2510 example: a @code{Staff} can contain many @code{Voice}s, and a
2511 @code{Score} can contain many @code{Staff} contexts.
2514 @sourceimage{context-example,5cm,,}
2517 Each context has the responsibility for enforcing some notation rules,
2518 creating some notation objects and maintaining the associated
2519 properties. For example, the @code{Voice} context may introduce an
2520 accidental and then the @code{Staff} context maintains the rule to
2521 show or suppress the accidental for the remainder of the measure. The
2522 synchronization of bar lines is handled at @code{Score} context.
2524 However, in some music we may not want the bar lines to be
2525 synchronized -- consider a polymetric score in 4/4 and 3/4 time. In
2526 such cases, we must modify the default settings of the @code{Score}
2527 and @code{Staff} contexts.
2529 For very simple scores, contexts are created implicitly, and you need
2530 not be aware of them. For larger pieces, such as anything with more
2531 than one staff, they must be
2532 created explicitly to make sure that you get as many staves as you
2533 need, and that they are in the correct order. For typesetting pieces
2534 with specialized notation, it can be useful to modify existing or
2535 to define new contexts.
2538 A complete description of all available contexts is in the program
2541 @rinternals{Contexts}.
2544 Translation @expansion{} Context.
2547 @c [TODO: describe propagation]