1 @c -*- coding: utf-8; mode: texinfo; -*-
2 @c This file is part of lilypond.tely
4 @c A menu is needed before every deeper *section nesting of @node's; run
5 @c M-x texinfo-all-menus-update
6 @c to automatically fill in these menus before saving changes
9 @chapter Spacing issues
11 The global paper layout is determined by three factors: the page layout, the
12 line breaks, and the spacing. These all influence each other. The
13 choice of spacing determines how densely each system of music is set.
14 This influences where line breaks are chosen, and thus ultimately, how
15 many pages a piece of music takes.
17 Globally speaking, this procedure happens in four steps: first,
18 flexible distances (@q{springs}) are chosen, based on durations. All
19 possible line breaking combinations are tried, and a @q{badness} score
20 is calculated for each. Then the height of each possible system is
21 estimated. Finally, a page breaking and line breaking combination is chosen
22 so that neither the horizontal nor the vertical spacing is too cramped
29 * Horizontal spacing::
31 * Displaying spacing::
32 * Vertical collision avoidance::
37 @section Paper and pages
39 This section deals with the boundaries that define the area
40 that music can be printed inside.
49 @subsection Paper size
55 To change the paper size, there are two commands,
57 #(set-default-paper-size "a4")
59 #(set-paper-size "a4")
63 The first command sets the size of all pages. The second command sets the
65 of the pages that the @code{\paper} block applies to -- if the @code{\paper}
66 block is at the top of the file, then it will apply to all pages. If the
67 @code{\paper} block is inside a @code{\book}, then the paper size will only
70 Support for the following paper sizes are included by default,
71 @code{a6}, @code{a5}, @code{a4}, @code{a3}, @code{legal}, @code{letter},
72 @code{11x17} (also known as tabloid).
74 Extra sizes may be added by editing the definition for
75 @code{paper-alist} in the initialization file @file{scm/paper.scm}.
80 If the symbol @code{landscape} is supplied as an argument to
81 @code{set-default-paper-size}, the pages will be rotated by 90 degrees,
82 and wider line widths will be set correspondingly.
85 #(set-default-paper-size "a6" 'landscape)
88 Setting the paper size will adjust a number of @code{\paper} variables
89 (such as margins). To use a particular paper size with altered
90 @code{\paper} variables, set the paper size before setting the variables.
94 @subsection Page formatting
96 @cindex page formatting
101 LilyPond will do page layout, set margins, and add headers and
102 footers to each page.
104 The default layout responds to the following settings in the
111 @funindex first-page-number
112 @item first-page-number
113 The value of the page number of the first page. Default is@tie{}1.
115 @funindex printfirst-page-number
116 @item print-first-page-number
117 If set to true, will print the page number in the first page. Default is
120 @funindex print-page-number
121 @item print-page-number
122 If set to false, page numbers will not be printed. Default is true.
124 @funindex paper-width
126 The width of the page. The default is taken from the current paper size,
127 see @ref{Paper size}.
129 @funindex paper-height
131 The height of the page. The default is taken from the current paper size,
132 see @ref{Paper size}.
136 Margin between header and top of the page. Default is@tie{}5mm.
138 @funindex bottom-margin
140 Margin between footer and bottom of the page. Default is@tie{}6mm.
142 @funindex left-margin
144 Margin between the left side of the page and the beginning of the
145 music. Unset by default, which means that the margins is determined
146 based on the @code{paper-width} and @code{line-width} to center the
151 The length of the systems. Default is @code{paper-width} minus @tie{}20mm.
153 @funindex head-separation
154 @item head-separation
155 Distance between the top-most music system and the page header. Default
158 @funindex foot-separation
159 @item foot-separation
160 Distance between the bottom-most music system and the page
161 footer. Default is@tie{}4mm.
163 @funindex page-top-space
165 Distance from the top of the printable area to the center of the first
166 staff. This only works for staves which are vertically small. Big staves
167 are set with the top of their bounding box aligned to the top of the
168 printable area. Default is@tie{}12mm.
170 @funindex ragged-bottom
172 If set to true, systems will not be spread vertically across the page. This
173 does not affect the last page. Default is false.
175 This should be set to true for pieces that have only two or three
176 systems per page, for example orchestral scores.
178 @funindex ragged-last-bottom
179 @item ragged-last-bottom
180 If set to false, systems will be spread vertically to fill the last
181 page. Default is true.
183 Pieces that amply fill two pages or more should have this set to
186 @funindex system-count
188 This variable, if set, specifies into how many lines a score should be
189 broken. Unset by default.
191 @funindex between-system-space
192 @item between-system-space
193 This dimensions determines the distance between systems. It is the
194 ideal distance between the center of the bottom staff of one system
195 and the center of the top staff of the next system. Default is@tie{}20mm.
197 Increasing this will provide a more even appearance of the page at the
198 cost of using more vertical space.
200 @funindex between-system-padding
201 @item between-system-padding
202 This dimension is the minimum amount of white space that will always
203 be present between the bottom-most symbol of one system, and the
204 top-most of the next system. Default is@tie{}4mm.
206 Increasing this will put systems whose bounding boxes almost touch
210 @funindex horizontal-shift
211 @item horizontal-shift
212 All systems (including titles and system separators) are shifted by
213 this amount to the right. Page markup, such as headers and footers are
214 not affected by this. The purpose of this variable is to make space
215 for instrument names at the left. Default is@tie{}0.
217 @funindex after-title-space
218 @item after-title-space
219 Amount of space between the title and the first system. Default is@tie{}5mm.
221 @funindex before-title-space
222 @item before-title-space
223 Amount of space between the last system of the previous piece and the
224 title of the next. Default is@tie{}10mm.
226 @funindex between-title-space
227 @item between-title-space
228 Amount of space between consecutive titles (e.g., the title of the
229 book and the title of a piece). Default is@tie{}2mm.
231 @funindex printallheaders
232 @item printallheaders
233 Setting this to #t will print all headers for each \score in the
234 output. Normally only the piece and opus \headers are printed.
236 @funindex systemSeparatorMarkup
237 @item systemSeparatorMarkup
238 This contains a markup object, which will be inserted between
239 systems. This is often used for orchestral scores. Unset by default.
241 The markup command @code{\slashSeparator} is provided as a sensible
244 @lilypond[ragged-right]
245 #(set-default-paper-size "a6" 'landscape)
248 \relative { c1 \break c1 }
251 systemSeparatorMarkup = \slashSeparator
256 @funindex blank-page-force
257 @item blank-page-force
258 The penalty for having a blank page in the middle of a
259 score. This is not used by @code{ly:optimal-breaking} since it will
260 never consider blank pages in the middle of a score. Default value
263 @funindex blank-last-page-force
264 @item blank-last-page-force
265 The penalty for ending the score on an odd-numbered page.
268 @funindex page-spacing-weight
269 @item page-spacing-weight
270 The relative importance of page (vertical) spacing and line (horizontal)
271 spacing. High values will make page spacing more important. Default
274 @funindex auto-first-page-number
275 @item auto-first-page-number
276 The page breaking algorithm is affected by the first page number being
277 odd or even. If this variable is set to #t, the page breaking algorithm
278 will decide whether to start with an odd or even number. This will
279 result in the first page number remaining as is or being increased by one.
291 ragged-last-bottom = ##t
295 You can also define these values in Scheme. In that case @code{mm},
296 @code{in}, @code{pt}, and @code{cm} are variables defined in
297 @file{paper-defaults.ly} with values in millimeters. That is why the
298 value must be multiplied in the example
302 #(define bottom-margin (* 2 cm))
306 The header and footer are created by the functions @code{make-footer}
307 and @code{make-header}, defined in @code{\paper}. The default
308 implementations are in @file{ly/@/paper@/-defaults@/.ly} and
309 @file{ly/@/titling@/-init@/.ly}.
311 The page layout itself is done by two functions in the
312 @code{\paper} block, @code{page-music-height} and
313 @code{page-make-stencil}. The former tells the line-breaking algorithm
314 how much space can be spent on a page, the latter creates the actual
315 page given the system to put on it.
320 The option right-margin is defined but doesn't set the right margin
321 yet. The value for the right margin has to be defined adjusting the
322 values of @code{left-margin} and @code{line-width}.
324 The default page header puts the page number and the @code{instrument}
325 field from the @code{\header} block on a line.
327 The titles (from the @code{\header@{@}} section) are treated as a
328 system, so @code{ragged-bottom} and @code{ragged-last-bottom} will
329 add space between the titles and the first system of the score.
333 @section Music layout
336 * Setting the staff size::
341 @node Setting the staff size
342 @subsection Setting the staff size
344 @cindex font size, setting
345 @cindex staff size, setting
346 @funindex layout file
348 To set the staff size globally for all scores in a file (or
349 in a @code{book} block, to be precise), use @code{set-global-staff-size}.
352 #(set-global-staff-size 14)
356 This sets the global default size to 14pt staff height and scales all
359 To set the staff size individually for each score, use
364 #(layout-set-staff-size 15)
369 The Feta font provides musical symbols at eight different
370 sizes. Each font is tuned for a different staff size: at a smaller size
371 the font becomes heavier, to match the relatively heavier staff lines.
372 The recommended font sizes are listed in the following table:
375 @multitable @columnfractions .15 .2 .22 .2
378 @tab @b{staff height (pt)}
379 @tab @b{staff height (mm)}
421 @c modern rental material?
426 These fonts are available in any sizes. The context property
427 @code{fontSize} and the layout property @code{staff-space} (in
428 @internalsref{StaffSymbol}) can be used to tune the size for individual
429 staves. The sizes of individual staves are relative to the global size.
437 This manual: @ref{Selecting notation font size}.
441 @subsection Score layout
445 While @code{\paper} contains settings that relate to the page formatting
446 of the whole document, @code{\layout} contains settings for score-specific
453 \override VerticalAxisGroup #'minimum-Y-extent = #'(-6 . 6)
456 \override TextScript #'padding = #1.0
457 \override Glissando #'thickness = #3
465 This manual: @ref{Changing context default settings}
468 @node Vertical spacing
469 @section Vertical spacing
471 @cindex vertical spacing
472 @cindex spacing, vertical
474 Vertical spacing is controlled by three things: the amount of
475 space available (i.e., paper size and margins), the amount of
476 space between systems, and the amount of space between
477 staves inside a system.
480 * Vertical spacing inside a system::
481 * Vertical spacing of piano staves::
482 * Vertical spacing between systems::
483 * Controlling spacing of individual systems::
484 * Two-pass vertical spacing::
488 @node Vertical spacing inside a system
489 @subsection Vertical spacing inside a system
491 @cindex distance between staves
492 @cindex staff distance
493 @cindex space between staves
494 @cindex space inside systems
496 The height of each system is determined automatically. To prevent
497 staves from bumping into each other, some minimum distances are set.
498 By changing these, you can put staves closer together. This
499 reduces the amount of space each system requires, and may result
500 in having more systems per page.
502 Normally staves are stacked vertically. To make staves maintain a
503 distance, their vertical size is padded. This is done with the
504 property @code{minimum-Y-extent}. When applied to a
505 @internalsref{VerticalAxisGroup}, it controls the size of a horizontal
506 line, such as a staff or a line of lyrics. @code{minimum-Y-extent}
507 takes a pair of numbers, so
508 if you want to make it smaller than its default @code{#'(-4 . 4)}
512 \override Staff.VerticalAxisGroup #'minimum-Y-extent = #'(-3 . 3)
516 This sets the vertical size of the current staff to 3 staff spaces on
517 either side of the center staff line. The value @code{(-3 . 3)} is
518 interpreted as an interval, where the center line is the 0, so the
519 first number is generally negative. The numbers need not match;
520 for example, the staff can be made larger at the bottom by setting
521 it to @code{(-6 . 4)}.
526 Internals: Vertical alignment of staves is handled by the
527 @internalsref{VerticalAlignment} object. The context parameters
528 specifying the vertical extent are described in connection with
529 the @internalsref{Axis_group_engraver}.
531 Example files: @inputfileref{input/regression/,page-spacing.ly},
532 @inputfileref{input/regression/,alignment-vertical-spacing.ly}.
535 @node Vertical spacing of piano staves
536 @subsection Vertical spacing of piano staves
538 The distance between staves of a @internalsref{PianoStaff} cannot be
539 computed during formatting. Rather, to make cross-staff beaming work
540 correctly, that distance has to be fixed beforehand.
542 The distance of staves in a @code{PianoStaff} is set with the
543 @code{forced-distance} property of the
544 @internalsref{VerticalAlignment} object, created in
545 @internalsref{PianoStaff}.
547 It can be adjusted as follows
549 \new PianoStaff \with @{
550 \override VerticalAlignment #'forced-distance = #7
557 This would bring the staves together at a distance of 7 staff spaces,
558 measured from the center line of each staff.
560 The difference is demonstrated in the following example,
561 @lilypond[quote,verbatim]
563 \new PianoStaff \with {
564 \override VerticalAlignment #'forced-distance = #7
579 Example files: @inputfileref{input/regression/,alignment-vertical-spacing.ly}.
582 @node Vertical spacing between systems
583 @subsection Vertical spacing between systems
585 Space between systems are controlled by four @code{\paper} variables,
589 between-system-space = 1.5\cm
590 between-system-padding = #1
592 ragged-last-bottom=##f
597 @node Controlling spacing of individual systems
598 @subsection Controlling spacing of individual systems
600 It is also possible to change the distance between for each system
601 individually. This is done by including the command
605 #"Score.NonMusicalPaperColumn"
606 #'line-break-system-details
607 #'((fixed-alignment-extra-space . 15))
611 at the line break before the system to be changed. The distance
612 @code{15} is distributed over all staves that have a fixed distance
613 alignment. For example,
615 @lilypond[ragged-right, fragment, relative=2, staffsize=13]
621 #"Score.NonMusicalPaperColumn"
622 #'line-break-system-details
623 #'((fixed-alignment-extra-space . 15))
631 The distance for @code{fixed-alignment-extra-space} may also be
635 @node Two-pass vertical spacing
636 @subsection Two-pass vertical spacing
638 In order to automatically stretch systems so that they should fill the
639 space left on a page, a two-pass technique can be used:
642 @item In the first pass, the amount of vertical space used to increase
643 the height of each system is computed and dumped to a file.
644 @item In the second pass, spacing inside the systems are
645 stretched according to the data in the page layout file.
648 The @code{ragged-bottom} property adds space between systems, while
649 the two-pass technique adds space between staffs inside a system.
651 To allow this behaviour, a @code{tweak-key} variable has to be set in
652 each score @code{\layout} block, and the tweaks included in each score
653 music, using the @code{\scoreTweak} music function.
657 %% include the generated page layout file:
658 \includePageLayoutFile
663 %% Include this score tweaks:
665 { \clef french c''1 \break c''1 }
667 \new Staff { \clef soprano g'1 g'1 }
668 \new Staff { \clef mezzosoprano e'1 e'1 }
669 \new Staff { \clef alto g1 g1 }
670 \new Staff { \clef bass c1 c1 }
673 piece = "Score with tweaks"
675 %% Define how to name the tweaks for this score:
676 \layout { #(define tweak-key "scoreA") }
681 For the first pass, the @code{dump-tweaks} option should be set to
682 generate the page layout file.
685 lilypond -b null -d dump-tweaks <file>.ly
689 @node Horizontal spacing
690 @section Horizontal Spacing
692 @cindex horizontal spacing
693 @cindex spacing, horizontal
696 * Horizontal spacing overview::
698 * Changing horizontal spacing::
703 @node Horizontal spacing overview
704 @subsection Horizontal spacing overview
706 The spacing engine translates differences in durations into stretchable
707 distances (@q{springs}) of differring lengths. Longer durations get
708 more space, shorter durations get less. The shortest durations get a
709 fixed amount of space (which is controlled by
710 @code{shortest-duration-space} in the @internalsref{SpacingSpanner}
711 object). The longer the duration, the more space it gets: doubling a
712 duration adds a fixed amount (this amount is controlled by
713 @code{spacing-increment}) of space to the note.
715 For example, the following piece contains lots of half, quarter, and
716 8th notes; the eighth note is followed by 1 note head width (NHW).
717 The quarter note is followed by 2 NHW, the half by 3 NHW, etc.
719 @lilypond[quote,fragment,verbatim,relative=1]
720 c2 c4. c8 c4. c8 c4. c8 c8
724 Normally, @code{spacing-increment} is set to 1.2 staff space, which is
725 approximately the width of a note head, and
726 @code{shortest-duration-space} is set to 2.0, meaning that the
727 shortest note gets 2.4 staff space (2.0 times the
728 @code{spacing-increment}) of horizontal space. This space is counted
729 from the left edge of the symbol, so the shortest notes are generally
730 followed by one NHW of space.
732 If one would follow the above procedure exactly, then adding a single
733 32nd note to a score that uses 8th and 16th notes, would widen up the
734 entire score a lot. The shortest note is no longer a 16th, but a 32nd,
735 thus adding 1 NHW to every note. To prevent this, the shortest
736 duration for spacing is not the shortest note in the score, but rather
737 the one which occurs most frequently.
740 The most common shortest duration is determined as follows: in every
741 measure, the shortest duration is determined. The most common shortest
742 duration is taken as the basis for the spacing, with the stipulation
743 that this shortest duration should always be equal to or shorter than
744 an 8th note. The shortest duration is printed when you run
745 @code{lilypond} with the @code{--verbose} option.
747 These durations may also be customized. If you set the
748 @code{common-shortest-duration} in @internalsref{SpacingSpanner}, then
749 this sets the base duration for spacing. The maximum duration for this
750 base (normally an 8th), is set through @code{base-shortest-duration}.
752 @funindex common-shortest-duration
753 @funindex base-shortest-duration
754 @funindex stem-spacing-correction
757 Notes that are even shorter than the common shortest note are
758 followed by a space that is proportional to their duration relative to
759 the common shortest note. So if we were to add only a few 16th notes
760 to the example above, they would be followed by half a NHW:
762 @lilypond[quote,fragment,verbatim,relative=2]
763 c2 c4. c8 c4. c16[ c] c4. c8 c8 c8 c4 c4 c4
767 In the introduction (see @ref{Engraving}), it was explained that stem
768 directions influence spacing. This is controlled with the
769 @code{stem-spacing-correction} property in the
770 @internalsref{NoteSpacing}, object. These are generated for every
771 @internalsref{Voice} context. The @code{StaffSpacing} object
772 (generated in @internalsref{Staff} context) contains the same property
773 for controlling the stem/bar line spacing. The following example shows
774 these corrections, once with default settings, and once with
775 exaggerated corrections:
777 @lilypond[quote,ragged-right]
781 \override Staff.NoteSpacing #'stem-spacing-correction = #1.5
782 \override Staff.StaffSpacing #'stem-spacing-correction = #1.5
788 Proportional notation is supported; see @ref{Proportional notation}.
793 Internals: @internalsref{SpacingSpanner}, @internalsref{NoteSpacing},
794 @internalsref{StaffSpacing}, @internalsref{SeparationItem}, and
795 @internalsref{SeparatingGroupSpanner}.
800 There is no convenient mechanism to manually override spacing. The
801 following work-around may be used to insert extra space into a score.
803 \once \override Score.SeparationItem #'padding = #1
806 No work-around exists for decreasing the amount of space.
809 @node New spacing area
810 @subsection New spacing area
812 New sections with different spacing parameters can be started with
813 @code{newSpacingSection}. This is useful when there are
814 sections with a different notions of long and short notes.
816 In the following example, the time signature change introduces a new
817 section, and hence the 16ths notes are spaced wider.
819 @lilypond[relative,fragment,verbatim,quote]
822 c8 c c4 c16[ c c8] c4
829 The @code{\newSpacingSection} command creates a new
830 @internalsref{SpacingSpanner} object, and hence new @code{\override}s
831 may be used in that location.
834 @node Changing horizontal spacing
835 @subsection Changing horizontal spacing
837 Horizontal spacing may be altered with the
838 @code{base-shortest-duration} property. Here
839 we compare the same music; once without altering
840 the property, and then altered. Larger values
841 of @code{ly:make-moment} will produce smaller
842 music. Note that @code{ly:make-moment} constructs
843 a duration, so @code{1 4} is a longer duration
846 @lilypond[relative,verbatim,line-width=12\cm]
849 g4 e e2 | f4 d d2 | c4 d e f | g4 g g2 |
850 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
851 d4 d d d | d4 e f2 | e4 e e e | e4 f g2 |
852 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
857 @lilypond[relative,verbatim,line-width=12\cm]
860 g4 e e2 | f4 d d2 | c4 d e f | g4 g g2 |
861 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
862 d4 d d d | d4 e f2 | e4 e e e | e4 f g2 |
863 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
868 \override SpacingSpanner
869 #'base-shortest-duration = #(ly:make-moment 1 16)
878 By default, spacing in tuplets depends on various non-duration
879 factors (such as accidentals, clef changes, etc). To disregard
880 such symbols and force uniform equal-duration spacing, use
881 @code{Score.SpacingSpanner #'uniform-stretching}. This
882 property can only be changed at the beginning of a score,
884 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
886 \override SpacingSpanner #'uniform-stretching = ##t
904 When @code{strict-note-spacing} is set, notes are spaced without
905 regard for clefs, bar lines, and grace notes,
907 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
908 \override Score.SpacingSpanner #'strict-note-spacing = ##t
909 \new Staff { c8[ c \clef alto c \grace { c16[ c] } c8 c c] c32[ c32] }
914 @subsection Line length
917 @cindex breaking pages
921 @funindex ragged-right
922 @funindex ragged-last
924 @c Although line-width can be set in \layout, it should be set in paper
925 @c block, to get page layout right.
926 @c Setting indent in \paper block makes not much sense, but it works.
928 @c Bit verbose and vague, use examples?
929 The most basic settings influencing the spacing are @code{indent} and
930 @code{line-width}. They are set in the @code{\layout} block. They
931 control the indentation of the first line of music, and the lengths of
934 If @code{ragged-right} is set to true in the @code{\layout} block, then
935 systems ends at their natural horizontal length, instead of being spread
936 horizontally to fill the whole line. This is useful for
937 short fragments, and for checking how tight the natural spacing is.
940 @cindex vertical spacing
942 The option @code{ragged-last} is similar to @code{ragged-right}, but
943 only affects the last line of the piece. No restrictions are put on
944 that line. The result is similar to formatting text paragraphs. In a
945 paragraph, the last line simply takes its natural horizontal length.
946 @c Note that for text there are several options for the last line.
947 @c While Knuth TeX uses natural length, lead typesetters use the same
948 @c stretch as the previous line. eTeX uses \lastlinefit to
949 @c interpolate between both these solutions.
966 * Optimal page breaking::
967 * Optimal page turning::
971 @subsection Line breaking
974 @cindex breaking lines
976 Line breaks are normally computed automatically. They are chosen so
977 that lines look neither cramped nor loose, and that consecutive lines
978 have similar density.
980 Occasionally you might want to override the automatic breaks; you can
981 do this by specifying @code{\break}. This will force a line break at
982 this point. Line breaks can only occur at places where there are bar
983 lines. If you want to have a line break where there is no bar line,
984 you can force an invisible bar line by entering @code{\bar
985 ""}. Similarly, @code{\noBreak} forbids a line break at a
989 @cindex regular line breaks
990 @cindex four bar music.
992 For line breaks at regular intervals use @code{\break} separated by
993 skips and repeated with @code{\repeat}:
995 << \repeat unfold 7 @{
996 s1 \noBreak s1 \noBreak
997 s1 \noBreak s1 \break @}
998 @emph{the real music}
1003 This makes the following 28 measures (assuming 4/4 time) be broken every
1004 4 measures, and only there.
1008 @code{\break}, and @code{\noBreak}.
1014 Internals: @internalsref{LineBreakEvent}.
1016 A linebreaking configuration can now be saved as a @code{.ly} file
1017 automatically. This allows vertical alignments to be stretched to
1018 fit pages in a second formatting run. This is fairly new and
1019 complicated; see @inputfileref{input/regression/,page-layout-twopass.ly}
1024 Line breaks can only occur if there is a @q{proper} bar line. A note
1025 which is hanging over a bar line is not proper, such as
1027 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1028 c4 c2 c2 \break % this does nothing
1029 c2 c4 | % a break here would work
1030 c4 c2 c4 ~ \break % as does this break
1034 To allow line breaks on such bar lines, the
1035 @code{Forbid_line_break_engraver} can be removed from @code{Voice}
1039 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1041 \remove "Forbid_line_break_engraver"
1043 c4 c2 c2 \break % now the break is allowed
1051 @subsection Page breaking
1053 The default page breaking may be overriden by inserting
1054 @code{\pageBreak} or @code{\noPageBreak} commands. These commands are
1055 analogous to @code{\break} and @code{\noBreak}. They should be
1056 inserted at a bar line. These commands force and forbid a page-break
1057 from happening. Of course, the @code{\pageBreak} command also forces
1060 Page breaks are computed by the @code{page-breaking} function.
1061 LilyPond provides two algorithms for computing page
1062 breaks, @code{ly:optimal-breaking} and @code{ly:page-turn-breaking}. The
1063 default is @code{ly:optimal-breaking}, but the value can be changed in
1064 the @code{\paper} block:
1068 #(define page-breaking ly:page-turn-breaking)
1072 The old page breaking algorithm is called
1073 @code{optimal-page-breaks}. If you are having trouble with the new page
1074 breakers, you can enable the old one as a workaround.
1078 @funindex \pageBreak
1080 @funindex \noPageBreak
1084 @node Optimal page breaking
1085 @subsection Optimal page breaking
1087 @funindex ly:optimal-breaking
1089 The @code{ly:optimal-breaking} function is LilyPond's default method of
1090 determining page breaks. It attempts to find a page breaking that minimizes
1091 cramping and stretching, both horizontally and vertically. Unlike
1092 @code{ly:page-turn-breaking}, it has no concept of page turns.
1095 @node Optimal page turning
1096 @subsection Optimal page turning
1098 @funindex ly:page-turn-breaking
1100 Often it is necessary to find a page breaking configuration so that there is
1101 a rest at the end of every second page. This way, the musician can turn the
1102 page without having to miss notes. The @code{ly:page-turn-breaking} function
1103 attempts to find a page breaking minimizing cramping and stretching, but with
1104 the additional restriction that it is only allowed to introduce page turns
1105 in specified places.
1107 There are two steps to using this page breaking function. First, you must
1108 enable it in the @code{\paper} block. Then, you must tell the function
1109 where you would like to allow page breaks.
1111 There are two ways to achieve the second step. First, you can specify each
1112 potential page turn manually, by inserting @code{\allowPageTurn} into your
1113 input file at the appropriate places.
1115 If this is too tedious, you can add a @code{Page_turn_engraver} to a Staff or
1116 Voice context. The @code{Page_turn_engraver} will scan the context for
1117 sections without notes (note that it does not scan for rests; it scans for
1118 the absence of notes. This is so that single-staff polyphony with rests in one
1119 of the parts does not throw off the @code{Page_turn_engraver}). When it finds
1120 a sufficiently long section without notes, the @code{Page_turn_engraver} will
1121 insert an @code{\allowPageTurn} at the final barline in that section, unless
1122 there is a @q{special} barline (such as a double bar), in which case the
1123 @code{\allowPageTurn} will be inserted at the final @q{special} barline in
1126 @funindex minimumPageTurnLength
1127 The @code{Page_turn_engraver} reads the context property
1128 @code{minimumPageTurnLength} to determine how long a note-free section must
1129 be before a page turn is considered. The default value for
1130 @code{minimumPageTurnLength} is @code{#(ly:make-moment 1 1)}. If you want
1131 to disable page turns, you can set it to something very large.
1134 \new Staff \with @{ \consists "Page_turn_engraver" @}
1137 R1 | % a page turn will be allowed here
1139 \set Staff.minimumPageTurnLength = #(ly:make-moment 5 2)
1140 R1 | % a page turn will not be allowed here
1142 R1*2 | % a page turn will be allowed here
1147 @funindex minimumRepeatLengthForPageTurn
1148 The @code{Page_turn_engraver} detects volta repeats. It will only allow a page
1149 turn during the repeat if there is enough time at the beginning and end of the
1150 repeat to turn the page back. The @code{Page_turn_engraver} can also disable
1151 page turns if the repeat is very short. If you set the context property
1152 @code{minimumRepeatLengthForPageTurn} then the @code{Page_turn_engraver} will
1153 only allow turns in repeats whose duration is longer than this value.
1157 There should only be one @code{Page_turn_engraver} in a score. If there is more
1158 than one, they will interfere with each other.
1161 @node Displaying spacing
1162 @section Displaying spacing
1164 @funindex annotate-spacing
1165 @cindex Spacing, display of properties
1167 To graphically display the dimensions of vertical properties that may
1168 be altered for page formatting, set @code{annotate-spacing} in the
1169 @code{\paper} block, like this
1173 #(set-default-paper-size "a6" 'landscape)
1177 \paper { annotate-spacing = ##t }
1181 @c need to have \book{} otherwise we get the separate systems. -hwn
1184 @c FIXME: really bad vagueness due to bug in annotate-spacing. -gp
1185 Some unit dimensions are measured in staff spaces, while others
1186 are measured in millimeters.
1188 (@var{a},@var{b}) are intervals, where @var{a} is the lower edge and
1189 @var{b} the upper edge of the interval.
1192 @node Vertical collision avoidance
1193 @section Vertical collision avoidance
1195 @funindex outside-staff-priority
1196 @funindex outside-staff-padding
1197 @funindex outside-staff-horizontal-padding
1199 Intuitively, there are some objects in musical notation that belong
1200 to the staff and there are other objects that should be placed outside
1201 the staff. Objects belonging outside the staff include things such as
1202 rehearsal marks, text and dynamic markings (from now on, these will
1203 be called outside-staff objects). LilyPond's rule for the
1204 vertical placement of outside-staff objects is to place them as close
1205 to the staff as possible but not so close that they collide with
1208 LilyPond uses the @code{outside-staff-priority} property to determine
1209 whether a grob is an outside-staff object: if @code{outside-staff-priority}
1210 is a number, the grob is an outside-staff object. In addition,
1211 @code{outside-staff-priority} tells LilyPond in which order the objects
1214 First, LilyPond places all the objects that do not belong outside
1215 the staff. Then it sorts the outside-staff objects according to their
1216 @code{outside-staff-priority} (in increasing order). One by one, LilyPond
1217 takes the outside-staff objects and places them so that they do
1218 not collide with any objects that have already been placed. That
1219 is, if two outside-staff grobs are competing for the same space, the one
1220 with the lower @code{outside-staff-priority} will be placed closer to
1223 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1226 \once \override TextScript #'outside-staff-priority = #1
1227 c4_"Text"\pp % this time the text will be closer to the staff
1229 % by setting outside-staff-priority to a non-number, we
1230 % disable the automatic collision avoidance
1231 \once \override TextScript #'outside-staff-priority = ##f
1232 \once \override DynamicLineSpanner #'outside-staff-priority = ##f
1233 c4_"Text"\pp % now they will collide
1236 The vertical padding between an outside-staff object and the
1237 previously-positioned grobs can be controlled with
1238 @code{outside-staff-padding}.
1240 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1241 \once \override TextScript #'outside-staff-padding = #0
1242 a'^"This text is placed very close to the note"
1243 \once \override TextScript #'outside-staff-padding = #3
1244 c^"This text is padded away from the previous text"
1245 c^"This text is placed close to the previous text"
1248 By default, outside-staff objects are placed without regard to
1249 their horizontal distance from the previously-posititioned grobs. This
1250 can lead to situations in which objects are placed very close to each
1251 other horizontally. Setting @code{outside-staff-horizontal-padding}
1252 causes an object to be offset vertically so that such a situation
1255 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1256 % the markup is too close to the following note
1259 % setting outside-staff-horizontal-padding fixes this
1261 \once \override TextScript #'outside-staff-horizontal-padding = #1