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 (``springs'') are chosen, based on durations. All
19 possible line breaking combinations are tried, and a ``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::
36 @section Paper and pages
38 This section deals with the boundaries that define the area
39 that music can be printed inside.
48 @subsection Paper size
54 To change the paper size, there are two commands,
56 #(set-default-paper-size "a4")
58 #(set-paper-size "a4")
62 The first command sets the size of all pages. The second command sets the
64 of the pages that the @code{\paper} block applies to -- if the @code{\paper}
65 block is at the top of the file, then it will apply to all pages. If the
66 @code{\paper} block is inside a @code{\book}, then the paper size will only
69 Support for the following paper sizes are included by default,
70 @code{a6}, @code{a5}, @code{a4}, @code{a3}, @code{legal}, @code{letter},
71 @code{11x17} (also known as tabloid).
73 Extra sizes may be added by editing the definition for
74 @code{paper-alist} in the initialization file @file{scm/paper.scm}.
79 If the symbol @code{landscape} is supplied as an argument to
80 @code{set-default-paper-size}, the pages will be rotated by 90 degrees,
81 and wider line widths will be set correspondingly.
84 #(set-default-paper-size "a6" 'landscape)
87 Setting the paper size will adjust a number of @code{\paper} variables
88 (such as margins). To use a particular paper size with altered
89 @code{\paper} variables, set the paper size before setting the variables.
93 @subsection Page formatting
95 @cindex page formatting
100 LilyPond will do page layout, set margins, and add headers and
101 footers to each page.
103 The default layout responds to the following settings in the
110 @funindex first-page-number
111 @item first-page-number
112 The value of the page number of the first page. Default is@tie{}1.
114 @funindex printfirst-page-number
115 @item print-first-page-number
116 If set to true, will print the page number in the first page. Default is
119 @funindex print-page-number
120 @item print-page-number
121 If set to false, page numbers will not be printed. Default is true.
123 @funindex paper-width
125 The width of the page. The default is taken from the current paper size,
126 see @ref{Paper size}.
128 @funindex paper-height
130 The height of the page. The default is taken from the current paper size,
131 see @ref{Paper size}.
135 Margin between header and top of the page. Default is@tie{}5mm.
137 @funindex bottom-margin
139 Margin between footer and bottom of the page. Default is@tie{}6mm.
141 @funindex left-margin
143 Margin between the left side of the page and the beginning of the
144 music. Unset by default, which means that the margins is determined
145 based on the @code{paper-width} and @code{line-width} to center the
150 The length of the systems. Default is @code{paper-width} minus @tie{}20mm.
152 @funindex head-separation
153 @item head-separation
154 Distance between the top-most music system and the page header. Default
157 @funindex foot-separation
158 @item foot-separation
159 Distance between the bottom-most music system and the page
160 footer. Default is@tie{}4mm.
162 @funindex page-top-space
164 Distance from the top of the printable area to the center of the first
165 staff. This only works for staves which are vertically small. Big staves
166 are set with the top of their bounding box aligned to the top of the
167 printable area. Default is@tie{}12mm.
169 @funindex ragged-bottom
171 If set to true, systems will not be spread vertically across the page. This
172 does not affect the last page. Default is false.
174 This should be set to true for pieces that have only two or three
175 systems per page, for example orchestral scores.
177 @funindex ragged-last-bottom
178 @item ragged-last-bottom
179 If set to false, systems will be spread vertically to fill the last
180 page. Default is true.
182 Pieces that amply fill two pages or more should have this set to
185 @funindex system-count
187 This variable, if set, specifies into how many lines a score should be
188 broken. Unset by default.
190 @funindex between-system-space
191 @item between-system-space
192 This dimensions determines the distance between systems. It is the
193 ideal distance between the center of the bottom staff of one system
194 and the center of the top staff of the next system. Default is@tie{}20mm.
196 Increasing this will provide a more even appearance of the page at the
197 cost of using more vertical space.
199 @funindex between-system-padding
200 @item between-system-padding
201 This dimension is the minimum amount of white space that will always
202 be present between the bottom-most symbol of one system, and the
203 top-most of the next system. Default is@tie{}4mm.
205 Increasing this will put systems whose bounding boxes almost touch
209 @funindex horizontal-shift
210 @item horizontal-shift
211 All systems (including titles and system separators) are shifted by
212 this amount to the right. Page markup, such as headers and footers are
213 not affected by this. The purpose of this variable is to make space
214 for instrument names at the left. Default is@tie{}0.
216 @funindex after-title-space
217 @item after-title-space
218 Amount of space between the title and the first system. Default is@tie{}5mm.
220 @funindex before-title-space
221 @item before-title-space
222 Amount of space between the last system of the previous piece and the
223 title of the next. Default is@tie{}10mm.
225 @funindex between-title-space
226 @item between-title-space
227 Amount of space between consecutive titles (e.g., the title of the
228 book and the title of a piece). Default is@tie{}2mm.
230 @funindex printallheaders
231 @item printallheaders
232 Setting this to #t will print all headers for each \score in a
233 \book. Normally only the piece and opus \headers are printed.
235 @funindex systemSeparatorMarkup
236 @item systemSeparatorMarkup
237 This contains a markup object, which will be inserted between
238 systems. This is often used for orchestral scores. Unset by default.
240 The markup command @code{\slashSeparator} is provided as a sensible
243 @lilypond[ragged-right]
246 \relative { c1 \break c1 }
249 systemSeparatorMarkup = \slashSeparator
254 @funindex blank-page-force
255 @item blank-page-force
256 The penalty for having a blank page in the middle of a
257 score. This is not used by @code{ly:optimal-breaking} since it will
258 never consider blank pages in the middle of a score. Default value
261 @funindex blank-last-page-force
262 @item blank-last-page-force
263 The penalty for ending the score on an odd-numbered page.
266 @funindex page-spacing-weight
267 @item page-spacing-weight
268 The relative importance of page (vertical) spacing and line (horizontal)
269 spacing. High values will make page spacing more important. Default
272 @funindex auto-first-page-number
273 @item auto-first-page-number
274 The page breaking algorithm is affected by the first page number being
275 odd or even. If this variable is set to #t, the page breaking algorithm
276 will decide whether to start with an odd or even number. This will
277 result in the first page number remaining as is or being increased by one.
289 ragged-last-bottom = ##t
293 You can also define these values in Scheme. In that case @code{mm},
294 @code{in}, @code{pt}, and @code{cm} are variables defined in
295 @file{paper-defaults.ly} with values in millimeters. That is why the
296 value must be multiplied in the example
300 #(define bottom-margin (* 2 cm))
304 The header and footer are created by the functions @code{make-footer}
305 and @code{make-header}, defined in @code{\paper}. The default
306 implementations are in @file{ly/@/paper@/-defaults@/.ly} and
307 @file{ly/@/titling@/-init@/.ly}.
309 The page layout itself is done by two functions in the
310 @code{\paper} block, @code{page-music-height} and
311 @code{page-make-stencil}. The former tells the line-breaking algorithm
312 how much space can be spent on a page, the latter creates the actual
313 page given the system to put on it.
318 The option right-margin is defined but doesn't set the right margin
319 yet. The value for the right margin has to be defined adjusting the
320 values of @code{left-margin} and @code{line-width}.
322 The default page header puts the page number and the @code{instrument}
323 field from the @code{\header} block on a line.
325 The titles (from the @code{\header@{@}} section) are treated as a
326 system, so @code{ragged-bottom} and @code{ragged-last-bottom} will
327 add space between the titles and the first system of the score.
331 @section Music layout
334 * Setting global staff size::
339 @node Setting global staff size
340 @subsection Setting global staff size
342 @cindex font size, setting
343 @cindex staff size, setting
344 @funindex layout file
346 To set the global staff size, use @code{set-global-staff-size}.
349 #(set-global-staff-size 14)
353 This sets the global default size to 14pt staff height and scales all
356 The Feta font provides musical symbols at eight different
357 sizes. Each font is tuned for a different staff size: at a smaller size
358 the font becomes heavier, to match the relatively heavier staff lines.
359 The recommended font sizes are listed in the following table:
362 @multitable @columnfractions .15 .2 .22 .2
365 @tab @b{staff height (pt)}
366 @tab @b{staff height (mm)}
408 @c modern rental material?
413 These fonts are available in any sizes. The context property
414 @code{fontSize} and the layout property @code{staff-space} (in
415 @internalsref{StaffSymbol}) can be used to tune the size for individual
416 staves. The sizes of individual staves are relative to the global size.
424 This manual: @ref{Selecting notation font size}.
428 @subsection Score layout
432 While @code{\paper} contains settings that relate to the page formatting
433 of the whole document, @code{\layout} contains settings for score-specific
440 \override VerticalAxisGroup #'minimum-Y-extent = #'(-6 . 6)
443 \override TextScript #'padding = #1.0
444 \override Glissando #'thickness = #3
452 This manual: @ref{Changing context default settings}
455 @node Vertical spacing
456 @section Vertical spacing
458 @cindex vertical spacing
459 @cindex spacing, vertical
461 Vertical spacing is controlled by three things: the amount of
462 space available (i.e., paper size and margins), the amount of
463 space between systems, and the amount of space between
464 staves inside a system.
467 * Vertical spacing inside a system::
468 * Vertical spacing of piano staves::
469 * Vertical spacing between systems::
470 * Controlling spacing of individual systems::
471 * Two-pass vertical spacing::
475 @node Vertical spacing inside a system
476 @subsection Vertical spacing inside a system
478 @cindex distance between staves
479 @cindex staff distance
480 @cindex space between staves
481 @cindex space inside systems
483 The height of each system is determined automatically. To prevent
484 staves from bumping into each other, some minimum distances are set.
485 By changing these, you can put staves closer together. This
486 reduces the amount of space each system requires, and may result
487 in having more systems per page.
489 Normally staves are stacked vertically. To make staves maintain a
490 distance, their vertical size is padded. This is done with the
491 property @code{minimum-Y-extent}. When applied to a
492 @internalsref{VerticalAxisGroup}, it controls the size of a horizontal
493 line, such as a staff or a line of lyrics. @code{minimum-Y-extent}
494 takes a pair of numbers, so
495 if you want to make it smaller than its default @code{#'(-4 . 4)}
499 \override Staff.VerticalAxisGroup #'minimum-Y-extent = #'(-3 . 3)
503 This sets the vertical size of the current staff to 3 staff spaces on
504 either side of the center staff line. The value @code{(-3 . 3)} is
505 interpreted as an interval, where the center line is the 0, so the
506 first number is generally negative. The numbers need not match;
507 for example, the staff can be made larger at the bottom by setting
508 it to @code{(-6 . 4)}.
513 Internals: Vertical alignment of staves is handled by the
514 @internalsref{VerticalAlignment} object. The context parameters
515 specifying the vertical extent are described in connection with
516 the @internalsref{Axis_group_engraver}.
518 Example files: @inputfileref{input/regression/,page-spacing.ly},
519 @inputfileref{input/regression/,alignment-vertical-spacing.ly}.
522 @node Vertical spacing of piano staves
523 @subsection Vertical spacing of piano staves
525 The distance between staves of a @internalsref{PianoStaff} cannot be
526 computed during formatting. Rather, to make cross-staff beaming work
527 correctly, that distance has to be fixed beforehand.
529 The distance of staves in a @code{PianoStaff} is set with the
530 @code{forced-distance} property of the
531 @internalsref{VerticalAlignment} object, created in
532 @internalsref{PianoStaff}.
534 It can be adjusted as follows
536 \new PianoStaff \with @{
537 \override VerticalAlignment #'forced-distance = #7
544 This would bring the staves together at a distance of 7 staff spaces,
545 measured from the center line of each staff.
547 The difference is demonstrated in the following example,
548 @lilypond[quote,verbatim]
550 \new PianoStaff \with {
551 \override VerticalAlignment #'forced-distance = #7
566 Example files: @inputfileref{input/regression/,alignment-vertical-spacing.ly}.
569 @node Vertical spacing between systems
570 @subsection Vertical spacing between systems
572 Space between systems are controlled by four @code{\paper} variables,
576 between-system-space = 1.5\cm
577 between-system-padding = #1
579 ragged-last-bottom=##f
584 @node Controlling spacing of individual systems
585 @subsection Controlling spacing of individual systems
587 It is also possible to change the distance between for each system
588 individually. This is done by including the command
592 #"Score.NonMusicalPaperColumn"
593 #'line-break-system-details
594 #'((fixed-alignment-extra-space . 15))
598 at the line break before the system to be changed. The distance
599 @code{15} is distributed over all staves that have a fixed distance
600 alignment. For example,
602 @lilypond[ragged-right, fragment, relative=2, staffsize=13]
608 #"Score.NonMusicalPaperColumn"
609 #'line-break-system-details
610 #'((fixed-alignment-extra-space . 15))
618 The distance for @code{fixed-alignment-extra-space} may also be
622 @node Two-pass vertical spacing
623 @subsection Two-pass vertical spacing
625 In order to automatically stretch systems so that they should fill the
626 space left on a page, a two-pass technique can be used:
629 @item In the first pass, the amount of vertical space used to increase
630 the height of each system is computed and dumped to a file.
631 @item In the second pass, the systems are stretched according to the
632 data in the page layout file.
635 To allow this behaviour, a @code{tweak-key} variable has to be set in
636 each score @code{\layout} block, and the tweaks included in each score
637 music, using the @code{\scoreTweak} music function.
641 %% include the generated page layout file:
642 \includePageLayoutFile
647 %% Include this score tweaks:
649 { \clef french c''1 \break c''1 }
651 \new Staff { \clef soprano g'1 g'1 }
652 \new Staff { \clef mezzosoprano e'1 e'1 }
653 \new Staff { \clef alto g1 g1 }
654 \new Staff { \clef bass c1 c1 }
657 piece = "Score with tweaks"
659 %% Define how to name the tweaks for this score:
660 \layout { #(define tweak-key "scoreA") }
665 For the first pass, the @code{dump-tweaks} option should be set to
666 generate the page layout file.
669 lilypond -b null -d dump-tweaks <file>.ly
673 @node Horizontal spacing
674 @section Horizontal Spacing
676 @cindex horizontal spacing
677 @cindex spacing, horizontal
680 * Horizontal spacing overview::
682 * Changing horizontal spacing::
687 @node Horizontal spacing overview
688 @subsection Horizontal spacing overview
690 The spacing engine translates differences in durations into stretchable
691 distances (``springs'') of differring lengths. Longer durations get
692 more space, shorter durations get less. The shortest durations get a
693 fixed amount of space (which is controlled by
694 @code{shortest-duration-space} in the @internalsref{SpacingSpanner}
695 object). The longer the duration, the more space it gets: doubling a
696 duration adds a fixed amount (this amount is controlled by
697 @code{spacing-increment}) of space to the note.
699 For example, the following piece contains lots of half, quarter, and
700 8th notes; the eighth note is followed by 1 note head width (NHW).
701 The quarter note is followed by 2 NHW, the half by 3 NHW, etc.
703 @lilypond[quote,fragment,verbatim,relative=1]
704 c2 c4. c8 c4. c8 c4. c8 c8
708 Normally, @code{spacing-increment} is set to 1.2 staff space, which is
709 approximately the width of a note head, and
710 @code{shortest-duration-space} is set to 2.0, meaning that the
711 shortest note gets 2.4 staff space (2.0 times the
712 @code{spacing-increment}) of horizontal space. This space is counted
713 from the left edge of the symbol, so the shortest notes are generally
714 followed by one NHW of space.
716 If one would follow the above procedure exactly, then adding a single
717 32nd note to a score that uses 8th and 16th notes, would widen up the
718 entire score a lot. The shortest note is no longer a 16th, but a 32nd,
719 thus adding 1 NHW to every note. To prevent this, the shortest
720 duration for spacing is not the shortest note in the score, but rather
721 the one which occurs most frequently.
724 The most common shortest duration is determined as follows: in every
725 measure, the shortest duration is determined. The most common shortest
726 duration is taken as the basis for the spacing, with the stipulation
727 that this shortest duration should always be equal to or shorter than
728 an 8th note. The shortest duration is printed when you run
729 @code{lilypond} with the @code{--verbose} option.
731 These durations may also be customized. If you set the
732 @code{common-shortest-duration} in @internalsref{SpacingSpanner}, then
733 this sets the base duration for spacing. The maximum duration for this
734 base (normally an 8th), is set through @code{base-shortest-duration}.
736 @funindex common-shortest-duration
737 @funindex base-shortest-duration
738 @funindex stem-spacing-correction
741 Notes that are even shorter than the common shortest note are
742 followed by a space that is proportional to their duration relative to
743 the common shortest note. So if we were to add only a few 16th notes
744 to the example above, they would be followed by half a NHW:
746 @lilypond[quote,fragment,verbatim,relative=2]
747 c2 c4. c8 c4. c16[ c] c4. c8 c8 c8 c4 c4 c4
751 In the introduction (see @ref{Engraving}), it was explained that stem
752 directions influence spacing. This is controlled with the
753 @code{stem-spacing-correction} property in the
754 @internalsref{NoteSpacing}, object. These are generated for every
755 @internalsref{Voice} context. The @code{StaffSpacing} object
756 (generated in @internalsref{Staff} context) contains the same property
757 for controlling the stem/bar line spacing. The following example shows
758 these corrections, once with default settings, and once with
759 exaggerated corrections:
761 @lilypond[quote,ragged-right]
765 \override Staff.NoteSpacing #'stem-spacing-correction = #1.5
766 \override Staff.StaffSpacing #'stem-spacing-correction = #1.5
772 Proportional notation is supported; see @ref{Proportional notation}.
777 Internals: @internalsref{SpacingSpanner}, @internalsref{NoteSpacing},
778 @internalsref{StaffSpacing}, @internalsref{SeparationItem}, and
779 @internalsref{SeparatingGroupSpanner}.
784 There is no convenient mechanism to manually override spacing. The
785 following work-around may be used to insert extra space into a score.
787 \once \override Score.SeparationItem #'padding = #1
790 No work-around exists for decreasing the amount of space.
793 @node New spacing area
794 @subsection New spacing area
796 New sections with different spacing parameters can be started with
797 @code{newSpacingSection}. This is useful when there are
798 sections with a different notions of long and short notes.
800 In the following example, the time signature change introduces a new
801 section, and hence the 16ths notes are spaced wider.
803 @lilypond[relative,fragment,verbatim,quote]
806 c8 c c4 c16[ c c8] c4
813 @node Changing horizontal spacing
814 @subsection Changing horizontal spacing
816 Horizontal spacing may be altered with the
817 @code{base-shortest-duration} property. Here
818 we compare the same music; once without altering
819 the property, and then altered. Larger values
820 of @code{ly:make-moment} will produce smaller
823 @lilypond[relative,verbatim,line-width=12\cm]
826 g4 e e2 | f4 d d2 | c4 d e f | g4 g g2 |
827 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
828 d4 d d d | d4 e f2 | e4 e e e | e4 f g2 |
829 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
834 @lilypond[relative,verbatim,line-width=12\cm]
837 g4 e e2 | f4 d d2 | c4 d e f | g4 g g2 |
838 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
839 d4 d d d | d4 e f2 | e4 e e e | e4 f g2 |
840 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
845 \override SpacingSpanner
846 #'base-shortest-duration = #(ly:make-moment 1 4)
855 By default, spacing in tuplets depends on various non-duration
856 factors (such as accidentals, clef changes, etc). To disregard
857 such symbols and force uniform equal-duration spacing, use
858 @code{Score.SpacingSpanner #'uniform-stretching}. This
859 property can only be changed at the beginning of a score,
861 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
863 \override SpacingSpanner #'uniform-stretching = ##t
881 When @code{strict-note-spacing} is set, notes are spaced without
882 regard for clefs, bar lines, and grace notes,
884 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
885 \override Score.SpacingSpanner #'strict-note-spacing = ##t
886 \new Staff { c8[ c \clef alto c \grace { c16[ c] } c8 c c] c32[ c32] }
891 @subsection Line length
894 @cindex breaking pages
898 @funindex ragged-right
899 @funindex ragged-last
901 @c Although line-width can be set in \layout, it should be set in paper
902 @c block, to get page layout right.
903 @c Setting indent in \paper block makes not much sense, but it works.
905 @c Bit verbose and vague, use examples?
906 The most basic settings influencing the spacing are @code{indent} and
907 @code{line-width}. They are set in the @code{\layout} block. They
908 control the indentation of the first line of music, and the lengths of
911 If @code{ragged-right} is set to true in the @code{\layout} block, then
912 systems ends at their natural horizontal length, instead of being spread
913 horizontally to fill the whole line. This is useful for
914 short fragments, and for checking how tight the natural spacing is.
917 @cindex vertical spacing
919 The option @code{ragged-last} is similar to @code{ragged-right}, but
920 only affects the last line of the piece. No restrictions are put on
921 that line. The result is similar to formatting text paragraphs. In a
922 paragraph, the last line simply takes its natural horizontal length.
923 @c Note that for text there are several options for the last line.
924 @c While Knuth TeX uses natural length, lead typesetters use the same
925 @c stretch as the previous line. eTeX uses \lastlinefit to
926 @c interpolate between both these solutions.
943 * Optimal page breaking::
944 * Optimal page turning::
948 @subsection Line breaking
951 @cindex breaking lines
953 Line breaks are normally computed automatically. They are chosen so
954 that lines look neither cramped nor loose, and that consecutive lines
955 have similar density.
957 Occasionally you might want to override the automatic breaks; you can
958 do this by specifying @code{\break}. This will force a line break at
959 this point. Line breaks can only occur at places where there are bar
960 lines. If you want to have a line break where there is no bar line,
961 you can force an invisible bar line by entering @code{\bar
962 ""}. Similarly, @code{\noBreak} forbids a line break at a
966 @cindex regular line breaks
967 @cindex four bar music.
969 For line breaks at regular intervals use @code{\break} separated by
970 skips and repeated with @code{\repeat}:
972 << \repeat unfold 7 @{
973 s1 \noBreak s1 \noBreak
974 s1 \noBreak s1 \break @}
975 @emph{the real music}
980 This makes the following 28 measures (assuming 4/4 time) be broken every
981 4 measures, and only there.
985 @code{\break}, and @code{\noBreak}.
991 Internals: @internalsref{LineBreakEvent}.
993 A linebreaking configuration can now be saved as a @code{.ly} file
994 automatically. This allows vertical alignments to be stretched to
995 fit pages in a second formatting run. This is fairly new and
996 complicated; see @inputfileref{input/regression/,page-layout-twopass.ly}
1001 Line breaks can only occur if there is a ``proper'' bar line. A note
1002 which is hanging over a bar line is not proper, such as
1004 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1005 c4 c2 c2 \break % this does nothing
1006 c2 c4 | % a break here would work
1007 c4 c2 c4 ~ \break % as does this break
1013 @subsection Page breaking
1015 The default page breaking may be overriden by inserting
1016 @code{\pageBreak} or @code{\noPageBreak} commands. These commands are
1017 analogous to @code{\break} and @code{\noBreak}. They should be
1018 inserted at a bar line. These commands force and forbid a page-break
1019 from happening. Of course, the @code{\pageBreak} command also forces
1022 Page breaks are computed by the @code{page-breaking} function.
1023 LilyPond provides two algorithms for computing page
1024 breaks, @code{ly:optimal-breaking} and @code{ly:page-turn-breaking}. The
1025 default is @code{ly:optimal-breaking}, but the value can be changed in
1026 the @code{\paper} block:
1030 #(define page-breaking ly:page-turn-breaking)
1034 The old page breaking algorithm is called
1035 @code{optimal-page-breaks}. If you are having trouble with the new page
1036 breakers, you can enable the old one as a workaround.
1040 @funindex \pageBreak
1042 @funindex \noPageBreak
1046 @node Optimal page breaking
1047 @subsection Optimal page breaking
1049 @funindex ly:optimal-breaking
1051 The @code{ly:optimal-breaking} function is LilyPond's default method of
1052 determining page breaks. It attempts to find a page breaking that minimizes
1053 cramping and stretching, both horizontally and vertically. Unlike
1054 @code{ly:page-turn-breaking}, it has no concept of page turns.
1057 @node Optimal page turning
1058 @subsection Optimal page turning
1060 @funindex ly:page-turn-breaking
1062 Often it is necessary to find a page breaking configuration so that there is
1063 a rest at the end of every second page. This way, the musician can turn the
1064 page without having to miss notes. The @code{ly:page-turn-breaking} function
1065 attempts to find a page breaking minimizing cramping and stretching, but with
1066 the additional restriction that it is only allowed to introduce page turns
1067 in specified places.
1069 There are two steps to using this page breaking function. First, you must
1070 enable it in the @code{\paper} block. Then, you must tell the function
1071 where you would like to allow page breaks.
1073 There are two ways to achieve the second step. First, you can specify each
1074 potential page turn manually, by inserting @code{\allowPageTurn} into your
1075 input file at the appropriate places.
1077 If this is too tedious, you can add a @code{Page_turn_engraver} to a Staff or
1078 Voice context. The @code{Page_turn_engraver} will scan the context for
1079 sections without notes (note that it does not scan for rests; it scans for
1080 the absence of notes. This is so that single-staff polyphony with rests in one
1081 of the parts does not throw off the @code{Page_turn_engraver}). When it finds
1082 a sufficiently long section without notes, the @code{Page_turn_engraver} will
1083 insert an @code{\allowPageTurn} at the final barline in that section, unless
1084 there is a ``special'' barline (such as a double bar), in which case the
1085 @code{\allowPageTurn} will be inserted at the final ``special'' barline in
1088 @funindex minimumPageTurnLength
1089 The @code{Page_turn_engraver} reads the context property
1090 @code{minimumPageTurnLength} to determine how long a note-free section must
1091 be before a page turn is considered. The default value for
1092 @code{minimumPageTurnLength} is @code{#(ly:make-moment 1 1)}. If you want
1093 to disable page turns, you can set it to something very large.
1096 \new Staff \with @{ \consists "Page_turn_engraver" @}
1099 R1 | % a page turn will be allowed here
1101 \set Staff.minimumPageTurnLength = #(ly:make-moment 5 2)
1102 R1 | % a page turn will not be allowed here
1104 R1*2 | % a page turn will be allowed here
1109 @funindex minimumRepeatLengthForPageTurn
1110 The @code{Page_turn_engraver} detects volta repeats. It will only allow a page
1111 turn during the repeat if there is enough time at the beginning and end of the
1112 repeat to turn the page back. The @code{Page_turn_engraver} can also disable
1113 page turns if the repeat is very short. If you set the context property
1114 @code{minimumRepeatLengthForPageTurn} then the @code{Page_turn_engraver} will
1115 only allow turns in repeats whose duration is longer than this value.
1119 The @code{Page_turn_engraver} does not respect time-scaled music. For example, the
1120 following example does not behave as expected:
1123 \new Staff \with @{ \consists "Page_turn_engraver" @}
1126 R1 | % a page turn will be allowed here
1127 a4 b \times 2/3 @{c d e@} |
1128 R1 | % a page turn will NOT be allowed here
1133 There should only be one @code{Page_turn_engraver} in a score. If there is more
1134 than one, they will interfere with each other.
1137 @node Displaying spacing
1138 @section Displaying spacing
1140 @funindex annotate-spacing
1141 @cindex Spacing, display of properties
1143 To graphically display the dimensions of vertical properties
1144 that may be altered for page formatting, use
1147 \paper { annotate-spacing = ##t }
1152 @c FIXME: really bad vagueness due to bug in annotate-spacing. -gp
1153 Some unit dimensions are measured in staff spaces, while others
1154 are measured in millimeters.
1156 (@var{a},@var{b}) are intervals, where @var{a} is the lower edge and
1157 @var{b} the upper edge of the interval.