2 @node Changing defaults
3 @chapter Changing defaults
6 The purpose of LilyPond's design is to provide the finest output
7 quality as a default. Nevertheless, it may happen that you need to
8 change this default layout. The layout is controlled through a large
9 number of proverbial ``knobs and switches.'' This chapter does not
10 list each and every knob. Rather, it outlines what groups of controls
11 are available and explains how to lookup which knob to use for a
14 The controls available for tuning are described in a separate
15 document, the @internalsref{Program reference} manual. This manual
16 lists all different variables, functions and options available in
17 LilyPond. It is written as a HTML document, which is available
18 @uref{http://lilypond.org/doc/Documentation/user/out-www/lilypond-internals/,on-line},
19 but is also included with the LilyPond documentation package.
21 There are three areas where the default settings may be changed:
24 @item Output: changing the appearance of individual
25 objects. For example, changing stem directions, or the location of
28 @item Context: changing aspects of the translation from music events to
29 notation. For example, giving each staff a separate time signature.
31 @item Global layout: changing the appearance of the spacing, line
32 breaks and page dimensions.
35 Then, there are separate systems for typesetting text (like
36 @emph{ritardando}) and selecting different fonts. This chapter also
39 Internally, LilyPond uses Scheme (a LISP dialect) to provide
40 infrastructure. Overriding layout decisions in effect accesses the
41 program internals, so it is necessary to learn a (very small) subset
42 of Scheme. That is why this chapter starts with a short tutorial on
43 entering numbers, lists, strings and symbols in Scheme.
49 * Interpretation contexts::
57 @section Scheme tutorial
61 @cindex Scheme, in-line code
62 @cindex accessing Scheme
63 @cindex evaluating Scheme
66 LilyPond uses the Scheme programming language, both as part of the
67 input syntax, and as internal mechanism to glue together modules of
68 the program. This section is a very brief overview of entering data in
69 Scheme.@footnote{If you want to know more about Scheme, see
70 @uref{http://www.schemers.org}.}
72 The most basic thing of a language is data: numbers, character
73 strings, lists, etc. Here is a list of data types that are relevant to
78 Boolean values are True or False. The Scheme for True is @code{#t}
79 and False is @code{#f}.
81 Numbers are entered in the standard fashion,
82 @code{1} is the (integer) number one, while @code{-1.5} is a
83 floating point number (a non-integer number).
85 Strings are enclosed in double quotes,
90 Strings may span several lines
97 Quotation marks and newlines can also be added with so-called escape
98 sequences. The string @code{a said "b"} is entered as
103 Newlines and backslashes are escaped with @code{\n} and @code{\\}
108 In a music file, snippets of Scheme code are introduced with the hash
109 mark @code{#}. So, the previous examples translated in LilyPond are
120 For the rest of this section, we will assume that the data is entered
121 in a music file, so we add @code{#}s everywhere.
123 Scheme can be used to do calculations. It uses @emph{prefix}
124 syntax. Adding 1 and 2 is written as @code{(+ 1 2)} rather than the
132 The arrow @result{} shows that the result of evaluating @code{(+ 1 2)}
133 is @code{3}. Calculations may be nested; the result of a function may
134 be used for another calculation.
142 These calculations are examples of evaluations; an expression like
143 @code{(* 3 4)} is replaced by its value @code{12}. A similar thing
144 happens with variables. After defining a variable
150 variables can also be used in expressions, here
153 twentyFour = #(* 2 twelve)
156 the number 24 is stored in the variable @code{twentyFour}.
158 The @emph{name} of a variable is also an expression, similar to a
159 number or a string. It is entered as
165 The quote mark @code{'} prevents Scheme interpreter from substituting
166 @code{24} for the @code{twentyFour}. Instead, we get the name
169 This syntax will be used very frequently, since many of the layout
170 tweaks involve assigning (Scheme) values to internal variables, for
174 \override Stem #'thickness = #2.6
177 This instruction adjusts the appearance of stems. The value @code{2.6}
178 is put into a the @code{thickness} variable of a @code{Stem}
179 object. This makes stems almost twice as thick as their normal size.
180 To distinguish between variables defined in input files (like
181 @code{twentyFour} in the example above), and internal variables, we
182 will call the latter ``properties.'' So, the stem object has a
183 @code{thickness} property.
185 Two-dimensional offsets (X and Y coordinates) as well as object sizes
186 (intervals with a left and right point) are entered as @code{pairs}. A
187 pair@footnote{In Scheme terminology, the pair is called @code{cons},
188 and its two elements are called car and cdr respectively.} is entered
189 as @code{(first . second)} and, like symbols, they must be quoted,
192 \override TextScript #'extra-offset = #'(1 . 2)
195 This assigns the pair (1, 2) to @code{extra-offset} variable of the
196 TextScript object. This moves the object 1 staff space to the right,
199 The two elements of a pair may be arbitrary values, for example
204 #'("blah-blah" . 3.14159265)
207 A list is entered by enclosing its elements in parentheses, and adding
208 a quote. For example,
214 We have been using lists all along. A calculation, like @code{(+ 1
215 2)} is also a list (containing the symbol @code{+} and the numbers 1
216 and 2). Normally lists are interpreted as calculations, and the Scheme
217 interpreter substitutes the outcome of the calculation. To enter a
218 list, we stop evaluation. This is done by quoting the list with a
219 quote @code{'} symbol. For calculations, do not use a quote.
221 Inside a quoted list or pair, there is no need to quote anymore. The
222 following is a pair of symbols, a list of symbols and a list of lists
227 #'(staff clef key-signature)
232 @section File structure
234 The following items may be present in a file at toplevel
237 @item An output definition, such as @code{\bookpaper}, @code{\midi}
238 and @code{\paper}. Such a definition at toplevel changes the default
239 settings for the block entered.
241 @item An @code{\header} block. This sets the global header block. This
242 is the block containing the definitions for book-wide settings, like
243 composer, title, etc.
245 @item An @code{\addquote} statement. See @ref{Quoting other voices}
246 for more information.
248 @item A @code{\score} block. This score will be formatted as a book
249 containing a single movement.
251 This behavior can be changed by setting the variable
252 @code{toplevel-score-handler} at toplevel. The default handler is
253 defined in the init file @file{scm/lily.scm}.
256 @item A @code{\book} block formats the block
258 This behavior can be changed by setting the variable
259 @code{toplevel-book-handler} at toplevel. The default handler is
260 defined in the init file @file{scm/lily.scm}.
263 @item A compound music expression, such as
268 This will format the piece as a book with a single movement.
271 This behavior can be changed by setting the variable
272 @code{toplevel-music-handler} at toplevel. The default handler is
273 defined in the init file @file{scm/lily.scm}.
277 The following example shows three things which may be entered at
281 % movements are non-justified by default
293 At any point in a file, any of the following lexical instructions can
297 @item @code{\version}
298 @item @code{\include}
299 @item @code{\encoding}
300 @item @code{\renameinput}
305 @node Interpretation contexts
306 @section Interpretation contexts
308 When music is printed, a lot of notation elements must be added to the
309 input, which is often bare bones. For example, compare the input and
310 output of the following example:
312 @lilypond[verbatim,relative=2]
316 The input is rather sparse, but in the output, bar lines, accidentals,
317 clef, and time signature are added. LilyPond @emph{interprets} the
318 input. During this step, the musical information is inspected in time
319 order, similar to reading a score from left to right. While reading,
320 the program remembers where measure boundaries are, and what pitches
321 need explicit accidentals. This information can be presented on
322 several levels. For example, the effect of an accidental is limited
323 to a single stave, while a bar line must be synchronized across the
326 Within LilyPond, these rules and bits of information are grouped in
327 so-called Contexts. Examples of context are @context{Voice},
328 @context{Staff}, and @context{Score}. They are hierarchical, for
329 example, a @context{Staff} can contain many @context{Voice}s, and a
330 @context{Score} can contain many @context{Staff} contexts.
332 Each context has the responsibility for enforcing some notation rules,
333 creating some notation objects and maintaining the associated
334 properties. So, the synchronization of bar lines is handled at
335 @context{Score} context. The @context{Voice} may introduce an
336 accidentals and then the @context{Staff} context maintains the rule to
337 show or suppress the accidental for the remainder of the measure.
339 For simple scores, contexts are created implicitly, and you need not
340 be aware of them. For larger pieces, such as piano music, they must be
341 created explicitly to make sure that you get as many staves as you
342 need, and that they are in the correct order. For typesetting pieces
343 with specialized notation, it can be useful to modify existing or
347 Full description of all available contexts is in the program
350 @internalsref{Contexts}.
353 Translation @arrow{} Context.
356 @c [TODO: describe propagation]
360 * Creating contexts::
361 * Changing context properties on the fly::
362 * Modifying context plug-ins::
363 * Layout tunings within contexts::
364 * Changing context default settings::
365 * Defining new contexts::
366 * Which properties to change::
369 @node Creating contexts
370 @subsection Creating contexts
372 For scores with only one voice and one staff, correct contexts are
373 created automatically. For more complex scores, it is necessary to
374 create them by hand. There are three commands which do this.
376 The easiest command is @code{\new}, and it also the quickest to type.
377 It is prepended to a music expression, for example
381 @cindex Context, creating
384 \new @var{type} @var{music expression}
388 where @var{type} is a context name (like @code{Staff} or
389 @code{Voice}). This command creates a new context, and starts
390 interpreting @var{music expression} with that.
392 A practical application of @code{\new} is a score with many
393 staves. Each part that should be on its own staff, is preceded with
396 @lilypond[verbatim,relative=2,raggedright]
397 << \new Staff { c4 c }
402 @cindex @code{\context}
404 Like @code{\new}, the @code{\context} command also directs a music
405 expression to a context object, but gives the context an extra name. The
409 \context @var{type} = @var{id} @var{music}
412 This form will search for an existing context of type @var{type}
413 called @var{id}. If that context does not exist yet, it is created.
414 This is useful if the context is referred to later on. For example, when
415 setting lyrics the melody is in a named context
418 \context Voice = "@b{tenor}" @var{music}
422 so the texts can be properly aligned to its notes,
425 \new Lyrics \lyricsto "@b{tenor}" @var{lyrics}
430 Another possibility is funneling two different music expressions into
431 one context. In the following example, articulations and notes are
435 music = \notes { c4 c4 }
436 arts = \notes { s4-. s4-> }
439 They are combined by sending both to the same @context{Voice} context,
442 << \new Staff \context Voice = "A" \music
443 \context Voice = "A" \arts
446 @lilypond[raggedright]
447 music = \notes { c4 c4 }
448 arts = \notes { s4-. s4-> }
450 \notes \relative c'' << \new Staff \context Voice = "A" \music
451 \context Voice = "A" \arts
456 @cindex @code{\context}
457 @cindex creating contexts
459 The third command for creating contexts is
461 \context @var{type} @var{music}
466 This is similar to @code{\context} with @code{= @var{id}}, but matches
467 any context of type @var{type}, regardless of its given name.
469 This variant is used with music expressions that can be interpreted at
470 several levels. For example, the @code{\applyoutput} command (see
471 @ref{Running a function on all layout objects}). Without an explicit
472 @code{\context}, it is usually is applied to @context{Voice}
475 \applyoutput #@var{function} % apply to Voice
478 To have it interpreted at the @context{Score} or @context{Staff} level use
482 \context Score \applyoutput #@var{function}
483 \context Staff \applyoutput #@var{function}
487 @node Changing context properties on the fly
488 @subsection Changing context properties on the fly
492 @cindex changing properties
494 Each context can have different @emph{properties}, variables contained
495 in that context. They can be changed during the interpretation step.
496 This is achieved by inserting the @code{\set} command in the music,
499 @code{\set } @var{context}@code{.}@var{prop}@code{ = #}@var{value}
503 @lilypond[verbatim,relative=2]
505 \set Score.skipBars = ##t
509 This command skips measures that have no notes. The result is that
510 multi rests are condensed. The value assigned is a Scheme object. In
511 this case, it is @code{#t}, the boolean True value.
513 If the @var{context} argument is left out, then the current bottom-most
514 context (typically @context{ChordNames}, @context{Voice}, or
515 @context{Lyrics}) is used. In this example,
517 @lilypond[verbatim,relative=2]
519 \set autoBeaming = ##f
524 the @var{context} argument to @code{\set} is left out, and the current
525 @internalsref{Voice} is used.
527 Contexts are hierarchical, so if a bigger context was specified, for
528 example @context{Staff}, then the change would also apply to all
529 @context{Voice}s in the current stave. The change is applied
530 `on-the-fly', during the music, so that the setting only affects the
531 second group of eighth notes.
533 @cindex @code{\unset}
535 There is also an @code{\unset} command,
537 @code{\set }@var{context}@code{.}@var{prop}
541 which removes the definition of @var{prop}. This command removes
542 the definition only if it is set in @var{context}. In
545 \set Staff.autoBeaming = ##f
546 \unset Voice.autoBeaming
550 the current @context{Voice} does not have the property, and the
551 definition at @context{Staff} level remains intact. Like @code{\set},
552 the @var{context} argument does not have to be specified for a bottom
555 Settings that should only apply to a single time-step can be entered
556 easily with @code{\once}, for example in
558 @lilypond[verbatim,relative=2]
560 \once \set fontSize = #4.7
565 the property @code{fontSize} is unset automatically after the second
568 A full description of all available context properties is in the
569 program reference, see
571 @internalsref{Tunable-context-properties}.
574 Translation @arrow{} Tunable context properties.
578 @node Modifying context plug-ins
579 @subsection Modifying context plug-ins
581 Notation contexts (like Score and Staff) not only store properties,
582 they also contain plug-ins, called ``engravers'' that create notation
583 elements. For example, the Voice context contains a
584 @code{Note_head_engraver} and the Staff context contains a
585 @code{Key_signature_engraver}.
587 For a full a description of each plug-in, see
589 @internalsref{Engravers}.
592 Program reference @arrow Translation @arrow{} Engravers.
594 Every context described in
596 @internalsref{Contexts}
599 Program reference @arrow Translation @arrow{} Context.
601 lists the engravers used for that context.
604 It can be useful to shuffle around these plug-ins. This is done by
605 starting a new context, with @code{\new} or @code{\context}, and
606 modifying it like this,
609 \new @var{context} \with @{
619 where the @dots{} should be the name of an engraver. Here is a simple
620 example which removes @code{Time_signature_engraver} and
621 @code{Clef_engraver} from a @code{Staff} context,
623 @lilypond[relative=1, verbatim]
628 \remove "Time_signature_engraver"
629 \remove "Clef_engraver"
636 In the second stave there are no time signature or clef symbols. This
637 is a rather crude method of making objects disappear since it will affect
638 the entire staff. The spacing will be adversely influenced too. A more
639 sophisticated methods of blanking objects is shown in @ref{Common
642 The next example shows a practical application. Bar lines and time
643 signatures are normally synchronized across the score. This is done
644 by the @code{Timing_engraver}. This plug-in keeps an administration of
645 time signature, location within the measure, etc. By moving the
646 @code{Timing_engraver} engraver from Score to Staff context, we can
647 have a score where each staff has its own time signature.
649 @cindex polymetric scores
652 @lilypond[relative=1,raggedright,verbatim]
654 \remove "Timing_engraver"
657 \consists "Timing_engraver"
663 \consists "Timing_engraver"
672 @node Layout tunings within contexts
673 @subsection Layout tunings within contexts
675 Each context is responsible for creating certain types of graphical
676 objects. The settings used for printing these objects are also stored by
677 context. By changing these settings, the appearance of objects can be
680 The syntax for this is
683 \override @var{context}.@var{name}@code{ #'}@var{property} = #@var{value}
686 Here @var{name} is the name of a graphical object, like @code{Stem} or
687 @code{NoteHead}, and @var{property} is an internal variable of the
688 formatting system (`grob property' or `layout property'). The latter is a
689 symbol, so it must be quoted. The subsection @ref{Constructing a
690 tweak} explains what to fill in for @var{name}, @var{property}, and
691 @var{value}. Here we only discuss functionality of this command.
696 \override Staff.Stem #'thickness = #4.0
700 makes stems thicker (the default is 1.3, with staff line thickness as a
701 unit). Since the command specifies @context{Staff} as context, it only
702 applies to the current staff. Other staves will keep their normal
703 appearance. Here we see the command in action:
705 @lilypond[verbatim,relative=2]
707 \override Staff.Stem #'thickness = #4.0
713 The @code{\override} command is executed during the interpreting phase,
714 and changes the definition of the @code{Stem} within
715 @context{Staff}. After the command all stems are thickened.
717 Analogous to @code{\set}, the @var{context} argument may be left out,
718 causing it to default to @context{Voice}, and adding @code{\once} applies
719 the change during one timestep only
721 @lilypond[verbatim,relative=2]
723 \once \override Stem #'thickness = #4.0
728 The @code{\override} must be done before the object is
729 started. Therefore, when altering @emph{Spanner} objects, like slurs or
730 beams, the @code{\override} command must be executed at the moment when
731 the object is created. In this example,
734 @lilypond[verbatim,relative=2]
735 \override Slur #'thickness = #3.0
737 \override Beam #'thickness = #0.6
742 the slur is fatter and the beam is not. This is because the command for
743 @code{Beam} comes after the Beam is started. Therefore it has no effect.
745 Analogous to @code{\unset}, the @code{\revert} command for a context
746 undoes a @code{\override} command; like with @code{\unset}, it only
747 affects settings that were made in the same context. In other words, the
748 @code{\revert} in the next example does not do anything.
751 \override Voice.Stem #'thickness = #4.0
752 \revert Staff.Stem #'thickness
760 Internals: @internalsref{OverrideProperty}, @internalsref{RevertProperty},
761 @internalsref{PropertySet}, @internalsref{All-backend-properties}, and
762 @internalsref{All-layout-objects}.
767 The back-end is not very strict in type-checking object properties.
768 Cyclic references in Scheme values for properties can cause hangs
772 @node Changing context default settings
773 @subsection Changing context default settings
775 The adjustments of the previous chapters can also be entered separate
776 from the music, in the @code{\paper} block,
785 \override Stem #'thickness
786 \remove "Time_signature_engraver"
797 takes the existing definition @context{Staff} from the identifier
798 @code{Staff}. This works analogously to other contexts.
803 \override Stem #'thickness
804 \remove "Time_signature_engraver"
808 affect all staves in the score.
810 The @code{\set} keyword is optional within the @code{\paper} block, so
823 It is not possible to collect changes in a variable, and apply them to
824 one @code{\context} definition by referring to that variable.
827 @node Defining new contexts
828 @subsection Defining new contexts
830 Specific contexts, like @context{Staff} and @code{Voice}, are made of
831 simple building blocks, and it is possible to compose engraver
832 plug-ins in different combinations, thereby creating new types of
835 The next example shows how to build a different type of
836 @context{Voice} context from scratch. It will be similar to
837 @code{Voice}, but print centered slash noteheads only. It can be used
838 to indicate improvisation in Jazz pieces,
840 @lilypond[raggedright]
843 \type "Engraver_group_engraver"
844 \consists "Note_heads_engraver"
845 \consists "Text_engraver"
846 \consists Pitch_squash_engraver
847 squashedPosition = #0
848 \override NoteHead #'style = #'slash
849 \override Stem #'transparent = ##t
853 \accepts "ImproVoice"
855 \score { \notes \relative c'' {
856 a4 d8 bes8 \new ImproVoice { c4^"ad lib" c
857 c4 c^"undress" c_"while playing :)" c }
863 These settings are again done within a @code{\context} block inside a
874 In the following discussion, the example input shown should go on the
875 @dots{} in the previous fragment.
877 First, name the context gets a name. Instead of @context{Voice} it
878 will be called @context{ImproVoice},
884 Since it is similar to the @context{Voice}, we want commands that work
885 on (existing) @context{Voice}s to remain working. This is achieved by
886 giving the new context an alias @context{Voice},
892 The context will print notes, and instructive texts
895 \consists Note_heads_engraver
896 \consists Text_engraver
899 but only on the center line,
902 \consists Pitch_squash_engraver
903 squashedPosition = #0
906 The @internalsref{Pitch_squash_engraver} modifies note heads (created
907 by @internalsref{Note_heads_engraver}) and sets their vertical
908 position to the value of @code{squashedPosition}, in this case
909 @code{0}, the center line.
911 The notes look like a slash, without a stem,
914 \override NoteHead #'style = #'slash
915 \override Stem #'transparent = ##t
919 All these plug-ins have to cooperate, and this is achieved with a
920 special plug-in, which must be marked with the keyword @code{\type}.
921 This should always be @internalsref{Engraver_group_engraver},
924 \type "Engraver_group_engraver"
927 Putting together, we get
932 \type "Engraver_group_engraver"
933 \consists "Note_heads_engraver"
934 \consists "Text_script_engraver"
935 \consists Pitch_squash_engraver
936 squashedPosition = #0
937 \override NoteHead #'style = #'slash
938 \override Stem #'transparent = ##t
943 Contexts form hierarchies. We want to hang the @context{ImproVoice}
944 under @context{Staff}, just like normal @code{Voice}s. Therefore, we
945 modify the @code{Staff} definition with the @code{\accepts}
946 command,@footnote{The opposite of @code{\accepts} is @code{\denies},
947 which is sometimes when reusing existing context definitions. }
958 Putting both into a @code{\paper} block, like
968 \accepts "ImproVoice"
973 Then the output at the start of this subsection can be entered as
977 \notes \relative c'' {
982 c c_"while playing :)"
991 @node Which properties to change
992 @subsection Which properties to change
995 There are many different properties. Not all of them are listed in
996 this manual. However, the program reference lists them all in the
997 section @internalsref{Tunable-context-properties}, and most properties
998 are demonstrated in one of the
1000 @uref{../../../../input/test/out-www/collated-files.html,tips-and-tricks}
1009 @section Tuning output
1011 In the previous section, we have already touched on a command that
1012 changes layout details, the @code{\override} command. In this section,
1013 we will look at in more detail how to use the command in practice.
1014 First, we will give a a few versatile commands, which are sufficient
1015 for many situations. The next section will discuss general use of
1019 There are situations where default layout decisions are not
1020 sufficient. In this section we discuss ways to override these
1023 Formatting is internally done by manipulating so called objects
1024 (graphic objects). Each object carries with it a set of properties
1025 (object or layout properties) specific to the object. For example, a
1026 stem object has properties that specify its direction, length, and
1029 The most direct way of tuning the output is to alter the values of
1030 these properties. There are two ways of doing that: First, you can
1031 temporarily change the definition of one type of object, thus
1032 affecting a whole set of objects. Second, you can select one specific
1033 object, and set a layout property in that object.
1035 Do not confuse layout properties with translation
1036 properties. Translation properties always use a mixed caps style
1037 naming, and are manipulated using @code{\set} and @code{\unset}:
1039 \set Context.propertyName = @var{value}
1042 Layout properties are use Scheme style variable naming, i.e. lower
1043 case words separated with dashes. They are symbols, and should always
1044 be quoted using @code{#'}. For example, this could be an imaginary
1045 layout property name:
1047 #'layout-property-name
1054 * Constructing a tweak::
1055 * Navigating the program reference::
1056 * Layout interfaces::
1057 * Determining the grob property::
1063 @subsection Common tweaks
1065 Some overrides are so common that predefined commands are provided as
1066 a short-cut, for example, @code{\slurUp} and @code{\stemDown}. These
1067 commands are described in
1071 @ref{Notation manual}, under the sections for slurs and stems
1074 The exact tuning possibilities for each type of layout object are
1075 documented in the program reference of the respective
1076 object. However, many layout objects share properties, which can be
1077 used to apply generic tweaks. We mention a few of these:
1080 @item The @code{extra-offset} property, which
1081 @cindex @code{extra-offset}
1082 has a pair of numbers as value, moves around objects in the printout.
1083 The first number controls left-right movement; a positive number will
1084 move the object to the right. The second number controls up-down
1085 movement; a positive number will move it higher. The units of these
1086 offsets are staff-spaces. The @code{extra-offset} property is a
1087 low-level feature: the formatting engine is completely oblivious to
1090 In the following example, the second fingering is moved a little to
1091 the left, and 1.8 staff space downwards:
1093 @cindex setting object properties
1095 @lilypond[relative=1,verbatim]
1098 \once \override Fingering
1099 #'extra-offset = #'(-0.3 . -1.8)
1104 Setting the @code{transparent} property will cause an object to be printed
1105 in `invisible ink': the object is not printed, but all its other
1106 behavior is retained. The object still takes up space, it takes part in
1107 collisions, and slurs, and ties and beams can be attached to it.
1109 @cindex transparent objects
1110 @cindex removing objects
1111 @cindex hiding objects
1112 @cindex invisible objects
1113 The following example demonstrates how to connect different voices
1114 using ties. Normally, ties only connect two notes in the same
1115 voice. By introducing a tie in a different voice,
1117 @lilypond[fragment,relative=2]
1126 and blanking a stem in that voice, the tie appears to cross voices:
1128 @lilypond[fragment,relative=2,verbatim]
1130 \once \override Stem #'transparent = ##t
1138 The @code{padding} property for objects with
1139 @cindex @code{padding}
1140 @code{side-position-interface} can be set to increase distance between
1141 symbols that are printed above or below notes. We only give an
1142 example; a more elaborate explanation is in @ref{Constructing a
1145 @lilypond[relative=1,verbatim]
1147 \override Script #'padding = #3
1153 More specific overrides are also possible. The next section
1154 discusses in depth how to figure out these statements for yourself.
1157 @node Constructing a tweak
1158 @subsection Constructing a tweak
1160 The general procedure of changing output, that is, entering
1164 \override Voice.Stem #'thickness = #3.0
1168 means that we have to determine these bits of information:
1171 @item the context: here @context{Voice}.
1172 @item the layout object: here @code{Stem}.
1173 @item the layout property: here @code{thickness}
1174 @item a sensible value: here @code{3.0}
1178 @cindex internal documentation
1179 @cindex finding graphical objects
1180 @cindex graphical object descriptions
1182 @cindex @code{\override}
1184 @cindex internal documentation
1186 We demonstrate how to glean this information from the notation manual
1187 and the program reference.
1189 The program reference is a set of HTML pages, which is part of the
1190 documentation package. On Unix systems, it is typically in
1191 @file{/usr/share/doc/lilypond}. If you have them, it is best to
1192 bookmark them in your webbrowser, because you will need them. They
1193 are also available on the web: go to the
1194 @uref{http://lilypond.org,LilyPond website}, click ``Documentation'',
1195 select the correct version, and then click ``Program reference.''
1197 If you have them, use the local HTML files. They will load faster,
1198 and they are exactly matched to LilyPond version installed.
1201 @node Navigating the program reference
1202 @subsection Navigating the program reference
1204 Suppose we want to move the fingering indication in the fragment
1207 @lilypond[relative=2,verbatim]
1213 If you visit the documentation of @code{Fingering} (in @ref{Fingering
1214 instructions}), you will notice that there is written:
1219 Program reference: @internalsref{FingerEvent} and @internalsref{Fingering}.
1223 This fragments points to two parts of the program reference: a page
1224 on @code{FingerEvent} and on @code{Fingering}.
1226 The page on @code{FingerEvent} describes the properties of the music
1227 expression for the input @code{-2}. The page contains many links
1228 forward. For example, it says
1231 Accepted by: @internalsref{Fingering_engraver},
1235 That link brings us to the documentation for the Engraver, the
1239 This engraver creates the following layout objects: @internalsref{Fingering}.
1242 In other words, once the @code{FingerEvent}s are interpreted, the
1243 @code{Fingering_engraver} plug-in will process them.
1244 The @code{Fingering_engraver} is also listed to create
1245 @internalsref{Fingering} objects,
1248 Lo and behold, that is also the
1249 second bit of information listed under @b{See also} in the Notation
1250 manual. By clicking around in the program reference, we can follow the
1251 flow of information within the program, either forward (like we did
1252 here), or backwards, following links like this:
1256 @item @internalsref{Fingering}:
1257 @internalsref{Fingering} objects are created by:
1258 @b{@internalsref{Fingering_engraver}}
1260 @item @internalsref{Fingering_engraver}:
1261 Music types accepted: @b{@internalsref{fingering-event}}
1262 @item @internalsref{fingering-event}:
1263 Music event type @code{fingering-event} is in Music objects of type
1264 @b{@internalsref{FingerEvent}}
1267 This path goes against the flow of information in the program: it
1268 starts from the output, and ends at the input event.
1270 The program reference can also be browsed like a normal document. It
1271 contains a chapter on
1273 @internalsref{Music-definitions},
1278 on @internalsref{Translation}, and the @internalsref{Backend}. Every
1279 chapter lists all the definitions used, and all properties that may be
1283 @node Layout interfaces
1284 @subsection Layout interfaces
1286 @internalsref{Fingering} is a layout object. Such an object is a
1287 symbol within the score. It has properties, which store numbers (like
1288 thicknesses and directions), but also pointers to related objects.
1289 A layout object is also called @emph{grob},
1291 which is short for Graphical Object.
1294 The page for @code{Fingering} lists the definitions for the
1295 @code{Fingering} object. For example, the page says
1298 @code{padding} (dimension, in staff space):
1303 which means that the number will be kept at a distance of at least 0.6
1307 Each layout object may have several functions as a notational or
1308 typographical element. For example, the Fingering object
1309 has the following aspects
1312 @item Its size is independent of the horizontal spacing, unlike slurs or beams
1314 @item It is a piece of text. Granted, it's usually a very short text.
1316 @item That piece of text is typeset with a font, unlike slurs or beams.
1317 @item Horizontally, the center of the symbol should be aligned to the
1318 center of the notehead
1319 @item Vertically, the symbol is placed next to the note and the staff.
1322 vertical position is also coordinated with other super and subscript
1326 Each of these aspects is captured in a so-called @emph{interface},
1327 which are listed on the @internalsref{Fingering} page at the bottom
1330 This object supports the following interfaces:
1331 @internalsref{item-interface},
1332 @internalsref{self-alignment-interface},
1333 @internalsref{side-position-interface}, @internalsref{text-interface},
1334 @internalsref{text-script-interface}, @internalsref{font-interface},
1335 @internalsref{finger-interface}, and @internalsref{grob-interface}.
1338 Clicking any of the links will take you to the page of the respective
1339 object interface. Each interface has a number of properties. Some of
1340 them are not user-serviceable (``Internal properties''), but others
1343 We have been talking of `the' @code{Fingering} object, but actually it
1344 does not amount to much. The initialization file
1345 @file{scm/define-grobs.scm} shows the soul of the `object',
1350 (print-function . ,Text_item::print)
1352 (staff-padding . 0.6)
1353 (self-alignment-X . 0)
1354 (self-alignment-Y . 0)
1355 (script-priority . 100)
1356 (font-encoding . number)
1358 (meta . ((interfaces . (finger-interface font-interface
1359 text-script-interface text-interface
1360 side-position-interface self-alignment-interface
1365 as you can see, @code{Fingering} is nothing more than a bunch of
1366 variable settings, and the webpage is directly generated from this
1369 @node Determining the grob property
1370 @subsection Determining the grob property
1373 Recall that we wanted to change the position of the @b{2} in
1375 @lilypond[relative=2,verbatim]
1381 Since the @b{2} is vertically positioned next to its note, we have to
1382 meddle with the interface associated with this positioning. This is
1383 done using @code{side-position-interface}. The page for this interface
1387 @code{side-position-interface}
1389 Position a victim object (this one) next to other objects (the
1390 support). The property @code{direction} signifies where to put the
1391 victim object relative to the support (left or right, up or down?)
1396 below this description, the variable @code{padding} is described as
1400 (dimension, in staff space)
1402 add this much extra space between objects that are next to each
1407 By increasing the value of @code{padding}, we can move away the
1408 fingering. The following command inserts 3 staff spaces of white
1409 between the note and the fingering:
1411 \once \override Fingering #'padding = #3
1414 Inserting this command before the Fingering object is created,
1415 i.e. before @code{c2}, yields the following result:
1417 @lilypond[relative=2,fragment,verbatim]
1418 \once \override Fingering
1426 In this case, the context for this tweak is @context{Voice}, which
1427 does not have to be specified for @code{\override}. This fact can
1428 also be deduced from the program reference, for the page for the
1429 @internalsref{Fingering_engraver} plug-in says
1432 Fingering_engraver is part of contexts: @dots{} @b{@internalsref{Voice}}
1440 * Selecting font sizes::
1446 @node Selecting font sizes
1447 @subsection Selecting font sizes
1449 The most common thing to change about the appearance of fonts is their
1450 size. The font size of any context can be easily changed by setting
1451 the @code{fontSize} property for that context. Its value is a number:
1452 negative numbers make the font smaller, positive numbers larger. An
1453 example is given below:
1455 @lilypond[fragment,relative=1,verbatim]
1456 c4 c4 \set fontSize = #-3
1459 This command will set @code{font-size} (see below) in all layout
1460 objects in the current context. It does not change the size of
1461 variable symbols, such as beams or slurs.
1463 The font size is set by modifying the @code{font-size} property. Its
1464 value is a number indicating the size relative to the standard size.
1465 Each step up is an increase of approximately 12% of the font size. Six
1466 steps is exactly a factor two. The Scheme function @code{magstep}
1467 converts a @code{font-size} number to a scaling factor.
1469 LilyPond has fonts in different design sizes: the music fonts for
1470 smaller sizes are chubbier, while the text fonts are relatively wider.
1471 Font size changes are achieved by scaling the design size that is
1472 closest to the desired size.
1474 The @code{font-size} mechanism does not work for fonts selected
1475 through @code{font-name}. These may be scaled with
1476 @code{font-magnification}.
1479 One of the uses of @code{fontSize} is to get smaller symbols for cue
1480 notes. An elaborate example of those is in
1481 @inputfileref{input/test,cue-notes.ly}.
1484 @cindex @code{font-style}
1488 The following commands set @code{fontSize} for the current voice:
1490 @cindex @code{\tiny}
1492 @cindex @code{\small}
1494 @cindex @code{\normalsize}
1499 @cindex magnification
1503 @node Font selection
1504 @subsection Font selection
1506 Font selection for the standard fonts, @TeX{}'s Computer Modern fonts,
1507 can also be adjusted with a more fine-grained mechanism. By setting
1508 the object properties described below, you can select a different font;
1509 all three mechanisms work for every object that supports
1510 @code{font-interface}:
1514 @item @code{font-encoding}
1515 is a symbol that sets layout of the glyphs. Choices include
1516 @code{text} for normal text, @code{braces} (for piano staff braces),
1517 @code{music} (the standard music font, including ancient glyphs),
1518 @code{dynamic} (for dynamic signs) and @code{number} for the number
1522 @item @code{font-family}
1523 is a symbol indicating the general class of the typeface. Supported are
1524 @code{roman} (Computer Modern), @code{sans}, and @code{typewriter}.
1526 @item @code{font-shape}
1527 is a symbol indicating the shape of the font, there are typically
1528 several font shapes available for each font family. Choices are
1529 @code{italic}, @code{caps}, and @code{upright}.
1531 @item @code{font-series}
1532 is a symbol indicating the series of the font. There are typically several
1533 font series for each font family and shape. Choices are @code{medium}
1538 Fonts selected in the way sketched above come from a predefined style
1541 The font used for printing a object can be selected by setting
1542 @code{font-name}, e.g.
1544 \override Staff.TimeSignature
1545 #'font-name = #"cmr17"
1549 Any font can be used, as long as it is available to @TeX{}. Possible
1550 fonts include foreign fonts or fonts that do not belong to the
1551 Computer Modern font family. The size of fonts selected in this way
1552 can be changed with the @code{font-magnification} property. For
1553 example, @code{2.0} blows up all letters by a factor 2 in both
1557 @cindex font magnification
1563 Init files: @file{ly/declarations-init.ly} contains hints how new
1564 fonts may be added to LilyPond.
1568 No style sheet is provided for other fonts besides the @TeX{}
1569 Computer Modern family.
1571 @cindex font selection
1572 @cindex font magnification
1573 @cindex @code{font-interface}
1577 @section Text markup
1582 @cindex typeset text
1584 LilyPond has an internal mechanism to typeset texts. You can access it
1585 with the keyword @code{\markup}. Within markup mode, you can enter texts
1586 similar to lyrics: simply enter them, surrounded by spaces:
1589 @lilypond[verbatim,fragment,relative=1]
1590 c1^\markup { hello }
1591 c1_\markup { hi there }
1592 c1^\markup { hi \bold there, is \italic anyone home? }
1595 @cindex font switching
1597 The markup in the example demonstrates font switching commands. The
1598 command @code{\bold} and @code{\italic} apply to the first following
1599 word only; enclose a set of texts with braces to apply a command
1602 \markup @{ \bold @{ hi there @} @}
1606 For clarity, you can also do this for single arguments, e.g.
1609 \markup { is \italic { anyone } home }
1612 @cindex font size, texts
1615 In markup mode you can compose expressions, similar to mathematical
1616 expressions, XML documents, and music expressions. The braces group
1617 notes into horizontal lines. Other types of lists also exist: you can
1618 stack expressions grouped with @code{<} and @code{>} vertically with
1619 the command @code{\column}. Similarly, @code{\center-align} aligns
1620 texts by their center lines:
1622 @lilypond[verbatim,fragment,relative=1]
1623 c1^\markup { \column < a bbbb c > }
1624 c1^\markup { \center-align < a bbbb c > }
1625 c1^\markup { \line < a b c > }
1629 Markups can be stored in variables, and these variables
1630 may be attached to notes, like
1632 allegro = \markup { \bold \large { Allegro } }
1633 \notes { a^\allegro b c d }
1637 Some objects have alignment procedures of their own, which cancel out
1638 any effects of alignments applied to their markup arguments as a
1639 whole. For example, the @internalsref{RehearsalMark} is horizontally
1640 centered, so using @code{\mark \markup @{ \left-align .. @}} has no
1643 Similarly, for moving whole texts over notes with
1644 @code{\raise}, use the following trick:
1646 "" \raise #0.5 raised
1649 The text @code{raised} is now raised relative to the empty string
1650 @code{""} which is not visible. Alternatively, complete objects can
1651 be moved with layout properties such as @code{padding} and
1652 @code{extra-offset}.
1658 Init files: @file{scm/new-markup.scm}.
1663 Text layout is ultimately done by @TeX{}, which does kerning of
1664 letters. LilyPond does not account for kerning, so texts will be
1665 spaced slightly too wide.
1667 Syntax errors for markup mode are confusing.
1669 Markup texts cannot be used in the titling of the @code{\header}
1670 field. Titles are made by La@TeX{}, so La@TeX{} commands should be used
1676 * Overview of text markup commands::
1679 @node Overview of text markup commands
1680 @subsection Overview of text markup commands
1682 @include markup-commands.tely
1686 @section Global layout
1688 The global layout determined by three factors: the page layout, the
1689 line breaks, and the spacing. These all influence each other. The
1690 choice of spacing determines how densely each system of music is set,
1691 which influences where line breaks are chosen, and thus
1692 ultimately how many pages a piece of music takes. This section
1693 explains how to tune the algorithm for spacing.
1695 Globally spoken, this procedure happens in three steps: first,
1696 flexible distances (``springs'') are chosen, based on durations. All
1697 possible line breaking combination are tried, and the one with the
1698 best results --- a layout that has uniform density and requires as
1699 little stretching or cramping as possible --- is chosen.
1701 After spacing and linebreaking, the systems are distributed across
1702 pages, taking into account the size of the page, and the size of the
1708 * Setting global staff size::
1709 * Vertical spacing::
1710 * Horizontal spacing::
1712 * Line length and line breaking::
1720 @node Setting global staff size
1721 @subsection Setting global staff size
1723 @cindex font size, setting
1724 @cindex staff size, setting
1725 @cindex @code{paper} file
1727 The Feta font provides musical symbols at eight different
1728 sizes. Each font is tuned for a different staff size: at a smaller size
1729 the font becomes heavier, to match the relatively heavier staff lines.
1730 The recommended font sizes are listed in the following table:
1732 @multitable @columnfractions .25 .25 .25 .25
1735 @tab @b{staff height (pt)}
1736 @tab @b{staff height (mm)}
1778 @c modern rental material ?
1782 These fonts are available in any sizes. The context property
1783 @code{fontSize} and the layout property @code{staff-space} (in
1784 @internalsref{StaffSymbol}) can be used to tune size for individual
1785 staves. The size of individual staves are relative to the global size,
1786 which can be set in the following manner:
1789 #(set-global-staff-size 14)
1792 This sets the global default size to 14pt staff height, and scales all
1797 This manual: @ref{Selecting font sizes}.
1802 * Vertical spacing::
1803 * Horizontal spacing::
1808 @node Vertical spacing
1809 @subsection Vertical spacing
1811 @cindex vertical spacing
1812 @cindex distance between staves
1813 @cindex staff distance
1814 @cindex between staves, distance
1815 @cindex staves per page
1816 @cindex space between staves
1818 The height of each system is determined automatically by LilyPond, to
1819 keep systems from bumping into each other, some minimum distances are
1820 set. By changing these, you can put staves closer together, and thus
1821 put more systems onto one page.
1823 Normally staves are stacked vertically. To make
1824 staves maintain a distance, their vertical size is padded. This is
1825 done with the property @code{minimumVerticalExtent}. It takes a pair
1826 of numbers, so if you want to make it smaller from its, then you could
1829 \set Staff.minimumVerticalExtent = #'(-4 . 4)
1831 This sets the vertical size of the current staff to 4 staff spaces on
1832 either side of the center staff line. The argument of
1833 @code{minimumVerticalExtent} is interpreted as an interval, where the
1834 center line is the 0, so the first number is generally negative. The
1835 staff can be made larger at the bottom by setting it to @code{(-6
1838 The piano staves are handled a little differently: to make cross-staff
1839 beaming work correctly, it is necessary that the distance between staves
1840 is fixed beforehand. This is also done with a
1841 @internalsref{VerticalAlignment} object, created in
1842 @internalsref{PianoStaff}. In this object the distance between the
1843 staves is fixed by setting @code{forced-distance}. If you want to
1844 override this, use a @code{\context} block as follows:
1849 \override VerticalAlignment #'forced-distance = #9
1854 This would bring the staves together at a distance of 9 staff spaces,
1855 measured from the center line of each staff.
1859 Internals: Vertical alignment of staves is handled by the
1860 @internalsref{VerticalAlignment} object.
1865 @node Horizontal spacing
1866 @subsection Horizontal Spacing
1868 The spacing engine translates differences in durations into
1869 stretchable distances (``springs'') of differing lengths. Longer
1870 durations get more space, shorter durations get less. The shortest
1871 durations get a fixed amount of space (which is controlled by
1872 @code{shortest-duration-space} in the @internalsref{SpacingSpanner} object).
1873 The longer the duration, the more space it gets: doubling a
1874 duration adds a fixed amount (this amount is controlled by
1875 @code{spacing-increment}) of space to the note.
1877 For example, the following piece contains lots of half, quarter, and
1878 8th notes, the eighth note is followed by 1 note head width (NHW).
1879 The quarter note is followed by 2 NHW, the half by 3 NHW, etc.
1880 @lilypond[fragment,verbatim,relative=1] c2 c4. c8 c4. c8 c4. c8 c8
1884 Normally, @code{shortest-duration-space} is set to 1.2, which is the
1885 width of a note head, and @code{shortest-duration-space} is set to
1886 2.0, meaning that the shortest note gets 2 NHW (i.e. 2 times
1887 @code{shortest-duration-space}) of space. For normal notes, this space
1888 is always counted from the left edge of the symbol, so the shortest
1889 notes are generally followed by one NHW of space.
1891 If one would follow the above procedure exactly, then adding a single
1892 32th note to a score that uses 8th and 16th notes, would widen up the
1893 entire score a lot. The shortest note is no longer a 16th, but a 32nd,
1894 thus adding 1 NHW to every note. To prevent this, the
1895 shortest duration for spacing is not the shortest note in the score,
1896 but the most commonly found shortest note. Notes that are even
1897 shorter this are followed by a space that is proportional to their
1898 duration relative to the common shortest note. So if we were to add
1899 only a few 16th notes to the example above, they would be followed by
1902 @lilypond[fragment,verbatim,relative=2]
1903 c2 c4. c8 c4. c16[ c] c4. c8 c8 c8 c4 c4 c4
1906 The most common shortest duration is determined as follows: in every
1907 measure, the shortest duration is determined. The most common short
1908 duration, is taken as the basis for the spacing, with the stipulation
1909 that this shortest duration should always be equal to or shorter than
1910 1/8th note. The shortest duration is printed when you run lilypond
1911 with @code{--verbose}. These durations may also be customized. If you
1912 set the @code{common-shortest-duration} in
1913 @internalsref{SpacingSpanner}, then this sets the base duration for
1914 spacing. The maximum duration for this base (normally 1/8th), is set
1915 through @code{base-shortest-duration}.
1917 @cindex @code{common-shortest-duration}
1918 @cindex @code{base-shortest-duration}
1919 @cindex @code{stem-spacing-correction}
1920 @cindex @code{spacing}
1922 In the Introduction it was explained that stem directions influence
1923 spacing. This is controlled with @code{stem-spacing-correction}
1924 property in @internalsref{NoteSpacing}, which are generated for every
1925 @internalsref{Voice} context. The @code{StaffSpacing} object
1926 (generated at @internalsref{Staff} context) contains the same property
1927 for controlling the stem/bar line spacing. The following example
1928 shows these corrections, once with default settings, and once with
1929 exaggerated corrections:
1935 \override Staff.NoteSpacing #'stem-spacing-correction = #1.5
1936 \override Staff.StaffSpacing #'stem-spacing-correction = #1.5
1940 \paper { raggedright = ##t } }
1943 @cindex SpacingSpanner, overriding properties
1945 Properties of the @internalsref{SpacingSpanner} must be overridden
1946 from the @code{\paper} block, since the @internalsref{SpacingSpanner} is
1947 created before any property commands are interpreted.
1949 \paper @{ \context @{
1951 \override SpacingSpanner #'spacing-increment = #3.0
1958 Internals: @internalsref{SpacingSpanner}, @internalsref{NoteSpacing},
1959 @internalsref{StaffSpacing}, @internalsref{SeparationItem}, and
1960 @internalsref{SeparatingGroupSpanner}.
1964 Spacing is determined on a score wide basis. If you have a score that
1965 changes its character (measured in durations) halfway during the
1966 score, the part containing the longer durations will be spaced too
1969 There is no convenient mechanism to manually override spacing. The
1970 following work-around may be used to insert extra space into a score.
1972 \once \override Score.SeparationItem #'padding = #1
1975 No work-around exists for decreasing the amount of space.
1984 @subsection Line breaking
1987 @cindex breaking lines
1989 Line breaks are normally computed automatically. They are chosen such
1990 that lines look neither cramped nor loose, and that consecutive lines
1991 have similar density.
1993 Occasionally you might want to override the automatic breaks; you can
1994 do this by specifying @code{\break}. This will force a line break at
1995 this point. Line breaks can only occur at places where there are bar
1996 lines. If you want to have a line break where there is no bar line,
1997 you can force an invisible bar line by entering @code{\bar
1998 ""}. Similarly, @code{\noBreak} forbids a line break at a
2002 @cindex regular line breaks
2003 @cindex four bar music.
2005 For line breaks at regular intervals use @code{\break} separated by
2006 skips and repeated with @code{\repeat}:
2008 << \repeat unfold 7 @{
2009 s1 \noBreak s1 \noBreak
2010 s1 \noBreak s1 \break @}
2011 @emph{the real music}
2016 This makes the following 28 measures (assuming 4/4 time) be broken every
2017 4 measures, and only there.
2021 @code{\break}, and @code{\noBreak}.
2022 @cindex @code{\break}
2023 @cindex @code{\noBreak}
2027 Internals: @internalsref{BreakEvent}.
2029 @node Line length and line breaking
2030 @subsection Line length and line breaking
2033 @cindex breaking pages
2035 @cindex @code{indent}
2036 @cindex @code{linewidth}
2038 The most basic settings influencing the spacing are @code{indent} and
2039 @code{linewidth}. They are set in the @code{\paper} block. They
2040 control the indentation of the first line of music, and the lengths of
2043 If @code{raggedright} is set to true in the @code{\paper}
2044 block, then the lines are justified at their natural length. This
2045 useful for short fragments, and for checking how tight the natural
2049 @cindex vertical spacing
2051 The option @code{raggedlast} is similar to @code{raggedright}, but
2052 only affects the last line of the piece. No restrictions are put on
2053 that line. The result is similar to formatting paragraphs. In a
2054 paragraph, the last line simply takes its natural length.
2060 Titles are created for each @code{\score} block, and over a
2063 The contents of the titles are taken from the @code{\header} blocks.
2064 The header block for a book supports the following
2067 The title of the music. Centered on top of the first page.
2069 Subtitle, centered below the title.
2071 Name of the poet, left flushed below the subtitle.
2073 Name of the composer, right flushed below the subtitle.
2075 Meter string, left flushed below the poet.
2077 Name of the opus, right flushed below the composer.
2079 Name of the arranger, right flushed below the opus.
2081 Name of the instrument, centered below the arranger.
2083 To whom the piece is dedicated.
2085 Name of the piece, left flushed below the instrument.
2088 This is a demonstration of the fields available,
2094 subtitle = "(and (the) subtitle)"
2095 subsubtitle = "Sub sub title"
2097 composer = "Composer"
2098 texttranslator = "Text Translator"
2100 arranger = "Arranger"
2101 instrument = "Instrument"
2114 Different fonts may be selected for each element, by using a
2115 @code{\markup}, e.g.
2119 title = \markup { \italic { The italic title } }
2123 A more advanced option is to change the Scheme functions
2124 @code{make-book-title} and @code{make-score-title} functions, defined
2125 in the @code{\bookpaper} of the @code{\book} block. These functions
2126 create a block of titling, given the information in the
2127 @code{\header}. The init file @file{ly/titling.scm} shows how the
2128 default format is created, and it may be used as a template for
2142 @subsection Page breaking
2144 The default page breaking may be overriden by inserting
2145 @code{\pageBreak} or @code{\noPageBreak} commands. These commands are
2146 analogous to @code{\break} and @code{\noBreak}. They should be
2147 inserted with a bar line. These commands force and forbid a page-break
2150 Page breaks are computed by the @code{page-breaking} function in the
2151 @code{\bookpaper} block.
2155 @cindex @code{\pageBreak}
2157 @cindex @code{\noPageBreak}
2161 @subsection Paper size
2165 @cindex @code{papersize}
2167 To change the paper size, there are two commands,
2169 #(set-default-paper-size "a4")
2171 #(set-paper-size "a4")
2174 The second one sets the size of the @code{\paper} block that it is in.
2178 @subsection Page layout
2182 @cindex header, page
2183 @cindex footer, page
2185 LilyPond will do page layout, setting margins and adding headers and
2186 footers to each page.
2188 The default layout responds to the following settings in the
2189 @code{\bookpaper} block
2193 The width of the page
2195 The height of the page
2197 Margin between header and top of the page
2199 Margin between footer and bottom of the page
2201 Distance between top-most music system and the page header
2203 Distance between bottom-most music system and the page footer
2206 The default page header puts the page number and the @code{instrument}
2207 field from the @code{\header} block on a line.
2212 The default footer is empty, except for the first page, where it the
2213 @code{copyright} field from @code{\header} is inserted, and the last
2214 page, where @code{tagline} from @code{\header} is added (the default
2215 tagline is ``Engraved by LilyPond (@var{version})''.
2217 The header and footer are created by the functions @code{make-footer}
2218 and @code{make-header}, defined in @code{\bookpaper}. The default
2219 implementations are in @file{scm/page-layout.scm}.
2221 The page layout itself is done by two functions:
2222 @code{page-music-height} and @code{page-make-stencil}. The former
2223 tells the line-breaking algorithm how much space can be spent on a
2224 page, the latter creates the actual page given the system to put on it.