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2 @c This file is part of lilypond.tely
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15 @chapter Spacing issues
17 The global paper layout is determined by three factors: the page layout, the
18 line breaks, and the spacing. These all influence each other. The
19 choice of spacing determines how densely each system of music is set.
20 This influences where line breaks are chosen, and thus ultimately, how
21 many pages a piece of music takes.
23 Globally speaking, this procedure happens in four steps: first,
24 flexible distances (@q{springs}) are chosen, based on durations. All
25 possible line breaking combinations are tried, and a @q{badness} score
26 is calculated for each. Then the height of each possible system is
27 estimated. Finally, a page breaking and line breaking combination is chosen
28 so that neither the horizontal nor the vertical spacing is too cramped
34 * Displaying spacing::
37 * Horizontal spacing::
42 @section Paper and pages
44 This section deals with the boundaries that define the area
45 that music can be printed inside.
54 @subsection Paper size
60 To change the paper size, there are two commands,
62 #(set-default-paper-size "a4")
64 #(set-paper-size "a4")
68 The first command sets the size of all pages. The second command sets the
70 of the pages that the @code{\paper} block applies to -- if the @code{\paper}
71 block is at the top of the file, then it will apply to all pages. If the
72 @code{\paper} block is inside a @code{\book}, then the paper size will only
75 Support for the following paper sizes are included by default,
76 @code{a6}, @code{a5}, @code{a4}, @code{a3}, @code{legal}, @code{letter},
77 @code{11x17} (also known as tabloid).
79 Extra sizes may be added by editing the definition for
80 @code{paper-alist} in the initialization file @file{scm/paper.scm}.
85 If the symbol @code{landscape} is supplied as an argument to
86 @code{set-default-paper-size}, the pages will be rotated by 90 degrees,
87 and wider line widths will be set correspondingly.
90 #(set-default-paper-size "a6" 'landscape)
93 Setting the paper size will adjust a number of @code{\paper} variables
94 (such as margins). To use a particular paper size with altered
95 @code{\paper} variables, set the paper size before setting the variables.
99 @subsection Page formatting
101 @cindex page formatting
106 LilyPond will do page layout, set margins, and add headers and
107 footers to each page.
109 The default layout responds to the following settings in the
116 @funindex first-page-number
117 @item first-page-number
118 The value of the page number of the first page. Default is@tie{}1.
120 @funindex print-first-page-number
121 @item print-first-page-number
122 If set to true, will print the page number in the first page. Default is
125 @funindex print-page-number
126 @item print-page-number
127 If set to false, page numbers will not be printed. Default is true.
129 @funindex paper-width
131 The width of the page. The default is taken from the current paper size,
132 see @ref{Paper size}.
134 @funindex paper-height
136 The height of the page. The default is taken from the current paper size,
137 see @ref{Paper size}.
141 Margin between header and top of the page. Default is@tie{}5mm.
143 @funindex bottom-margin
145 Margin between footer and bottom of the page. Default is@tie{}6mm.
147 @funindex left-margin
149 Margin between the left side of the page and the beginning of the
150 music. Unset by default, which means that the margins is determined
151 based on the @code{paper-width} and @code{line-width} to center the
156 The length of the systems. Default is @code{paper-width} minus @tie{}20mm.
158 @funindex head-separation
159 @item head-separation
160 Distance between the top-most music system and the page header. Default
163 @funindex foot-separation
164 @item foot-separation
165 Distance between the bottom-most music system and the page
166 footer. Default is@tie{}4mm.
168 @funindex page-top-space
170 Distance from the top of the printable area to the center of the first
171 staff. This only works for staves which are vertically small. Big staves
172 are set with the top of their bounding box aligned to the top of the
173 printable area. Default is@tie{}12mm.
175 @funindex ragged-bottom
177 If set to true, systems will not be spread vertically across the page. This
178 does not affect the last page. Default is false.
180 This should be set to true for pieces that have only two or three
181 systems per page, for example orchestral scores.
183 @funindex ragged-last-bottom
184 @item ragged-last-bottom
185 If set to false, systems will be spread vertically to fill the last
186 page. Default is true.
188 Pieces that amply fill two pages or more should have this set to
191 @funindex system-count
193 This variable, if set, specifies into how many lines a score should be
194 broken. Unset by default.
196 @funindex between-system-space
197 @item between-system-space
198 This dimensions determines the distance between systems. It is the
199 ideal distance between the center of the bottom staff of one system
200 and the center of the top staff of the next system. Default is@tie{}20mm.
202 Increasing this will provide a more even appearance of the page at the
203 cost of using more vertical space.
205 @funindex between-system-padding
206 @item between-system-padding
207 This dimension is the minimum amount of white space that will always
208 be present between the bottom-most symbol of one system, and the
209 top-most of the next system. Default is@tie{}4mm.
211 Increasing this will put systems whose bounding boxes almost touch
214 @funindex page-breaking-between-system-padding
215 @item between-system-padding
216 This variable tricks the page breaker into thinking that
217 @code{between-system-padding} is set to something different than it
218 really is. For example, if this variable is set to something substantially
219 larger than @code{between-system-padding}, then the page-breaker will put
220 fewer systems on each page.
222 @funindex horizontal-shift
223 @item horizontal-shift
224 All systems (including titles and system separators) are shifted by
225 this amount to the right. Page markup, such as headers and footers are
226 not affected by this. The purpose of this variable is to make space
227 for instrument names at the left. Default is@tie{}0.
229 @funindex after-title-space
230 @item after-title-space
231 Amount of space between the title and the first system. Default is@tie{}5mm.
233 @funindex before-title-space
234 @item before-title-space
235 Amount of space between the last system of the previous piece and the
236 title of the next. Default is@tie{}10mm.
238 @funindex between-title-space
239 @item between-title-space
240 Amount of space between consecutive titles (e.g., the title of the
241 book and the title of a piece). Default is@tie{}2mm.
243 @funindex printallheaders
244 @item printallheaders
245 Setting this to #t will print all headers for each \score in the
246 output. Normally only the piece and opus \headers are printed.
248 @funindex systemSeparatorMarkup
249 @item systemSeparatorMarkup
250 This contains a markup object, which will be inserted between
251 systems. This is often used for orchestral scores. Unset by default.
253 The markup command @code{\slashSeparator} is provided as a sensible
256 @lilypond[ragged-right]
257 #(set-default-paper-size "a6" 'landscape)
260 \relative { c1 \break c1 }
263 systemSeparatorMarkup = \slashSeparator
268 @funindex blank-page-force
269 @item blank-page-force
270 The penalty for having a blank page in the middle of a
271 score. This is not used by @code{ly:optimal-breaking} since it will
272 never consider blank pages in the middle of a score. Default value
275 @funindex blank-last-page-force
276 @item blank-last-page-force
277 The penalty for ending the score on an odd-numbered page.
280 @funindex page-spacing-weight
281 @item page-spacing-weight
282 The relative importance of page (vertical) spacing and line (horizontal)
283 spacing. High values will make page spacing more important. Default
286 @funindex auto-first-page-number
287 @item auto-first-page-number
288 The page breaking algorithm is affected by the first page number being
289 odd or even. If this variable is set to #t, the page breaking algorithm
290 will decide whether to start with an odd or even number. This will
291 result in the first page number remaining as is or being increased by one.
299 The header and footer are created by the functions make-footer and
300 make-header, defined in \paper. The default implementations are in
301 ly/paper-defaults.ly and ly/titling-init.ly.
303 The page layout itself is done by two functions in the \paper block,
304 page-music-height and page-make-stencil. The former tells the
305 line-breaking algorithm how much space can be spent on a page, the
306 latter creates the actual page given the system to put on it.
308 You can define paper block values in Scheme. In that case mm, in, pt,
309 and cm are variables defined in paper-defaults.ly with values in
310 millimeters. That is why the value 2 cm must be multiplied in the
315 #(define bottom-margin (* 2 cm))
327 ragged-last-bottom = ##t
331 This second example centers page numbers at the bottom of every page.
335 print-page-number = ##t
336 print-first-page-number = ##t
337 oddHeaderMarkup = \markup \fill-line @{ " " @}
338 evenHeaderMarkup = \markup \fill-line @{ " " @}
339 oddFooterMarkup = \markup @{ \fill-line @{
340 \bold \fontsize #3 \on-the-fly #print-page-number-check-first
341 \fromproperty #'page:page-number-string @} @}
342 evenFooterMarkup = \markup @{ \fill-line @{
343 \bold \fontsize #3 \on-the-fly #print-page-number-check-first
344 \fromproperty #'page:page-number-string @} @}
348 You can also define these values in Scheme. In that case @code{mm},
349 @code{in}, @code{pt}, and @code{cm} are variables defined in
350 @file{paper-defaults.ly} with values in millimeters. That is why the
351 value must be multiplied in the example
355 #(define bottom-margin (* 2 cm))
359 The header and footer are created by the functions @code{make-footer}
360 and @code{make-header}, defined in @code{\paper}. The default
361 implementations are in @file{ly/@/paper@/-defaults@/.ly} and
362 @file{ly/@/titling@/-init@/.ly}.
364 The page layout itself is done by two functions in the
365 @code{\paper} block, @code{page-music-height} and
366 @code{page-make-stencil}. The former tells the line-breaking algorithm
367 how much space can be spent on a page, the latter creates the actual
368 page given the system to put on it.
373 The option right-margin is defined but doesn't set the right margin
374 yet. The value for the right margin has to be defined adjusting the
375 values of @code{left-margin} and @code{line-width}.
377 The default page header puts the page number and the @code{instrument}
378 field from the @code{\header} block on a line.
380 The titles (from the @code{\header@{@}} section) are treated as a
381 system, so @code{ragged-bottom} and @code{ragged-last-bottom} will
382 add space between the titles and the first system of the score.
386 @section Music layout
389 * Setting the staff size::
394 @node Setting the staff size
395 @subsection Setting the staff size
397 @cindex font size, setting
398 @cindex staff size, setting
399 @funindex layout file
401 To set the staff size globally for all scores in a file (or
402 in a @code{book} block, to be precise), use @code{set-global-staff-size}.
405 #(set-global-staff-size 14)
409 This sets the global default size to 14pt staff height and scales all
412 To set the staff size individually for each score, use
417 #(layout-set-staff-size 15)
422 The Feta font provides musical symbols at eight different
423 sizes. Each font is tuned for a different staff size: at a smaller size
424 the font becomes heavier, to match the relatively heavier staff lines.
425 The recommended font sizes are listed in the following table:
428 @multitable @columnfractions .15 .2 .22 .2
431 @tab @b{staff height (pt)}
432 @tab @b{staff height (mm)}
474 @c modern rental material?
479 These fonts are available in any sizes. The context property
480 @code{fontSize} and the layout property @code{staff-space} (in
481 @internalsref{StaffSymbol}) can be used to tune the size for individual
482 staves. The sizes of individual staves are relative to the global size.
490 This manual: @ref{Selecting notation font size}.
494 @subsection Score layout
498 While @code{\paper} contains settings that relate to the page formatting
499 of the whole document, @code{\layout} contains settings for score-specific
506 \override VerticalAxisGroup #'minimum-Y-extent = #'(-6 . 6)
509 \override TextScript #'padding = #1.0
510 \override Glissando #'thickness = #3
518 This manual: @ref{Changing context default settings}.
521 @node Displaying spacing
522 @section Displaying spacing
524 @funindex annotate-spacing
525 @cindex Spacing, display of properties
527 To graphically display the dimensions of vertical properties that may
528 be altered for page formatting, set @code{annotate-spacing} in the
529 @code{\paper} block, like this
533 #(set-default-paper-size "a6" 'landscape)
537 \paper { annotate-spacing = ##t }
541 @c need to have \book{} otherwise we get the separate systems. -hwn
544 @c FIXME: really bad vagueness due to bug in annotate-spacing. -gp
545 Some unit dimensions are measured in staff spaces, while others
546 are measured in millimeters.
548 (@var{a},@var{b}) are intervals, where @var{a} is the lower edge and
549 @var{b} the upper edge of the interval.
558 * Optimal page breaking::
559 * Optimal page turning::
561 * Using an extra voice for breaks::
565 @subsection Line breaking
568 @cindex breaking lines
570 Line breaks are normally computed automatically. They are chosen so
571 that lines look neither cramped nor loose, and that consecutive lines
572 have similar density.
574 Occasionally you might want to override the automatic breaks; you can
575 do this by specifying @code{\break}. This will force a line break at
576 this point. Line breaks can only occur at places where there are bar
577 lines. If you want to have a line break where there is no bar line,
578 you can force an invisible bar line by entering @code{\bar
579 ""}. Similarly, @code{\noBreak} forbids a line break at a
583 @cindex regular line breaks
584 @cindex four bar music.
586 For line breaks at regular intervals use @code{\break} separated by
587 skips and repeated with @code{\repeat}:
589 << \repeat unfold 7 @{
590 s1 \noBreak s1 \noBreak
591 s1 \noBreak s1 \break @}
592 @emph{the real music}
597 This makes the following 28 measures (assuming 4/4 time) be broken every
598 4 measures, and only there.
602 @code{\break}, and @code{\noBreak}.
608 Internals: @internalsref{LineBreakEvent}.
610 A linebreaking configuration can be saved as a @code{.ly} file
611 automatically. This allows vertical alignments to be stretched to
612 fit pages in a second formatting run. This is fairly new and
613 complicated. More details are available in
618 Line breaks can only occur if there is a @q{proper} bar line. A note
619 which is hanging over a bar line is not proper, such as
621 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
622 c4 c2 c2 \break % this does nothing
623 c2 c4 | % a break here would work
624 c4 c2 c4 ~ \break % as does this break
628 To allow line breaks on such bar lines, the
629 @code{Forbid_line_break_engraver} can be removed from @code{Voice}
633 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
635 \remove "Forbid_line_break_engraver"
637 c4 c2 c2 \break % now the break is allowed
645 @subsection Page breaking
647 The default page breaking may be overriden by inserting
648 @code{\pageBreak} or @code{\noPageBreak} commands. These commands are
649 analogous to @code{\break} and @code{\noBreak}. They should be
650 inserted at a bar line. These commands force and forbid a page-break
651 from happening. Of course, the @code{\pageBreak} command also forces
654 Page breaks are computed by the @code{page-breaking} function.
655 LilyPond provides two algorithms for computing page
656 breaks, @code{ly:optimal-breaking} and @code{ly:page-turn-breaking}. The
657 default is @code{ly:optimal-breaking}, but the value can be changed in
658 the @code{\paper} block:
662 #(define page-breaking ly:page-turn-breaking)
666 The old page breaking algorithm is called
667 @code{optimal-page-breaks}. If you are having trouble with the new page
668 breakers, you can enable the old one as a workaround.
674 @funindex \noPageBreak
678 @node Optimal page breaking
679 @subsection Optimal page breaking
681 @funindex ly:optimal-breaking
683 The @code{ly:optimal-breaking} function is LilyPond's default method of
684 determining page breaks. It attempts to find a page breaking that minimizes
685 cramping and stretching, both horizontally and vertically. Unlike
686 @code{ly:page-turn-breaking}, it has no concept of page turns.
689 @node Optimal page turning
690 @subsection Optimal page turning
692 @funindex ly:page-turn-breaking
694 Often it is necessary to find a page breaking configuration so that there is
695 a rest at the end of every second page. This way, the musician can turn the
696 page without having to miss notes. The @code{ly:page-turn-breaking} function
697 attempts to find a page breaking minimizing cramping and stretching, but with
698 the additional restriction that it is only allowed to introduce page turns
701 There are two steps to using this page breaking function. First, you must
702 enable it in the @code{\paper} block. Then, you must tell the function
703 where you would like to allow page breaks.
705 There are two ways to achieve the second step. First, you can specify each
706 potential page turn manually, by inserting @code{\allowPageTurn} into your
707 input file at the appropriate places.
709 If this is too tedious, you can add a @code{Page_turn_engraver} to a Staff or
710 Voice context. The @code{Page_turn_engraver} will scan the context for
711 sections without notes (note that it does not scan for rests; it scans for
712 the absence of notes. This is so that single-staff polyphony with rests in one
713 of the parts does not throw off the @code{Page_turn_engraver}). When it finds
714 a sufficiently long section without notes, the @code{Page_turn_engraver} will
715 insert an @code{\allowPageTurn} at the final barline in that section, unless
716 there is a @q{special} barline (such as a double bar), in which case the
717 @code{\allowPageTurn} will be inserted at the final @q{special} barline in
720 @funindex minimumPageTurnLength
721 The @code{Page_turn_engraver} reads the context property
722 @code{minimumPageTurnLength} to determine how long a note-free section must
723 be before a page turn is considered. The default value for
724 @code{minimumPageTurnLength} is @code{#(ly:make-moment 1 1)}. If you want
725 to disable page turns, you can set it to something very large.
728 \new Staff \with @{ \consists "Page_turn_engraver" @}
731 R1 | % a page turn will be allowed here
733 \set Staff.minimumPageTurnLength = #(ly:make-moment 5 2)
734 R1 | % a page turn will not be allowed here
736 R1*2 | % a page turn will be allowed here
741 @funindex minimumRepeatLengthForPageTurn
742 The @code{Page_turn_engraver} detects volta repeats. It will only allow a page
743 turn during the repeat if there is enough time at the beginning and end of the
744 repeat to turn the page back. The @code{Page_turn_engraver} can also disable
745 page turns if the repeat is very short. If you set the context property
746 @code{minimumRepeatLengthForPageTurn} then the @code{Page_turn_engraver} will
747 only allow turns in repeats whose duration is longer than this value.
751 There should only be one @code{Page_turn_engraver} in a score. If there is more
752 than one, they will interfere with each other.
755 @node Explicit breaks
756 @subsection Explicit breaks
758 Lily sometimes rejects explicit @code{\break} and @code{\pageBreak}
759 commands. There are two commands to override this behavior:
762 \override NonMusicalPaperColumn #'line-break-permission = ##f
763 \override NonMusicalPaperColumn #'page-break-permission = ##f
766 When @code{line-break-permission} is overriden to false, Lily will insert
767 line breaks at explicit @code{\break} commands and nowhere else. When
768 @code{page-break-permission} is overriden to false, Lily will insert
769 page breaks at explicit @code{\pageBreak} commands and nowhere else.
771 @lilypond[quote,verbatim]
780 \override NonMusicalPaperColumn #'line-break-permission = ##f
781 \override NonMusicalPaperColumn #'page-break-permission = ##f
784 \repeat unfold 2 { c'8 c'8 c'8 c'8 } \break
785 \repeat unfold 4 { c'8 c'8 c'8 c'8 } \break
786 \repeat unfold 6 { c'8 c'8 c'8 c'8 } \break
787 \repeat unfold 8 { c'8 c'8 c'8 c'8 } \pageBreak
788 \repeat unfold 8 { c'8 c'8 c'8 c'8 } \break
789 \repeat unfold 6 { c'8 c'8 c'8 c'8 } \break
790 \repeat unfold 4 { c'8 c'8 c'8 c'8 } \break
791 \repeat unfold 2 { c'8 c'8 c'8 c'8 }
798 @node Using an extra voice for breaks
799 @subsection Using an extra voice for breaks
801 Line- and page-breaking information usually appears within note entry directly.
806 \repeat unfold 2 @{ c'4 c'4 c'4 c'4 @}
808 \repeat unfold 3 @{ c'4 c'4 c'4 c'4 @}
813 This makes @code{\break} and @code{\pageBreak} commands easy to enter but mixes
814 music entry with information that specifies how music should lay out
815 on the page. You can keep music entry and line- and page-breaking
816 information in two separate places by introducing an extra voice to
817 contain the breaks. This extra voice
818 contains only skips together with @code{\break}, @code{pageBreak} and other
819 breaking layout information.
821 @lilypond[quote,verbatim]
831 \repeat unfold 2 { c'4 c'4 c'4 c'4 }
832 \repeat unfold 3 { c'4 c'4 c'4 c'4 }
833 \repeat unfold 6 { c'4 c'4 c'4 c'4 }
834 \repeat unfold 5 { c'4 c'4 c'4 c'4 }
840 This pattern becomes especially helpful when overriding
841 @code{line-break-system-details} and the other useful but long properties of
842 @code{NonMusicalPaperColumnGrob}, as explained in @ref{Vertical spacing}.
844 @lilypond[quote,verbatim]
849 \overrideProperty "Score.NonMusicalPaperColumn"
850 #'line-break-system-details #'((Y-offset . 0))
853 \overrideProperty "Score.NonMusicalPaperColumn"
854 #'line-break-system-details #'((Y-offset . 35))
857 \overrideProperty "Score.NonMusicalPaperColumn"
858 #'line-break-system-details #'((Y-offset . 70))
861 \overrideProperty "Score.NonMusicalPaperColumn"
862 #'line-break-system-details #'((Y-offset . 105))
866 \repeat unfold 2 { c'4 c'4 c'4 c'4 }
867 \repeat unfold 3 { c'4 c'4 c'4 c'4 }
868 \repeat unfold 6 { c'4 c'4 c'4 c'4 }
869 \repeat unfold 5 { c'4 c'4 c'4 c'4 }
876 @node Vertical spacing
877 @section Vertical spacing
879 @cindex vertical spacing
880 @cindex spacing, vertical
882 Vertical spacing is controlled by three things: the amount of
883 space available (i.e., paper size and margins), the amount of
884 space between systems, and the amount of space between
885 staves inside a system.
888 * Vertical spacing inside a system::
889 * Vertical spacing between systems::
890 * Explicit staff and system positioning::
891 * Two-pass vertical spacing::
892 * Vertical collision avoidance::
896 @node Vertical spacing inside a system
897 @subsection Vertical spacing inside a system
899 @cindex distance between staves
900 @cindex staff distance
901 @cindex space between staves
902 @cindex space inside systems
904 The height of each system is determined automatically. To prevent
905 staves from bumping into each other, some minimum distances are set.
906 By changing these, you can put staves closer together. This
907 reduces the amount of space each system requires, and may result
908 in having more systems per page.
910 Normally staves are stacked vertically. To make staves maintain a
911 distance, their vertical size is padded. This is done with the
912 property @code{minimum-Y-extent}. When applied to a
913 @internalsref{VerticalAxisGroup}, it controls the size of a horizontal
914 line, such as a staff or a line of lyrics. @code{minimum-Y-extent}
915 takes a pair of numbers, so
916 if you want to make it smaller than its default @code{#'(-4 . 4)}
920 \override Staff.VerticalAxisGroup #'minimum-Y-extent = #'(-3 . 3)
924 This sets the vertical size of the current staff to 3 staff spaces on
925 either side of the center staff line. The value @code{(-3 . 3)} is
926 interpreted as an interval, where the center line is the 0, so the
927 first number is generally negative. The numbers need not match;
928 for example, the staff can be made larger at the bottom by setting
929 it to @code{(-6 . 4)}.
931 After page breaks are determined, the vertical spacing within each
932 system is reevaluated in order to fill the page more evenly; if a page
933 has space left over, systems are stretched in order to fill that space.
934 The amount of stretching can be configured though the @code{max-stretch}
935 property of the @internalsref{VerticalAlignment} grob. To disable this
936 stretching entirely, set @code{max-stretch} to zero.
938 In some situations, you may want to stretch most of a system while
939 leaving some parts fixed. For example, if a piano part occurs in the
940 middle of an orchestral score, you may want to leave the piano staves
941 close to each other while stretching the rest of the score. The
942 @code{keep-fixed-while-stretching} property of
943 @internalsref{VerticalAxisGroup} can be used to achieve this. When set
944 to @code{##t}, this property keeps its staff (or line of lyrics) from
945 moving relative to the one directly above it. In the example above,
946 you would override @code{keep-fixed-while-stretching} to @code{##t} in
947 the second piano staff:
950 #(set-default-paper-size "a6")
951 #(set-global-staff-size 14.0)
955 ragged-last-bottom = ##f
963 \new Staff {c' d' e' f'}
964 \new Staff {c' d' e' f'}
965 \new Staff {c' d' e' f'}
970 \new Staff {c' d' e' f'}
972 \override VerticalAxisGroup #'keep-fixed-while-stretching = ##t
979 \new Staff {c' d' e' f'}
980 \new Staff {c' d' e' f'}
989 Internals: Vertical alignment of staves is handled by the
990 @internalsref{VerticalAlignment} object. The context parameters
991 specifying the vertical extent are described in connection with
992 the @internalsref{Axis_group_engraver}.
994 Example files: @lsr{spacing,page-spacing.ly},
995 @lsr{spacing,alignment-vertical-spacing.ly}.
998 @node Vertical spacing between systems
999 @subsection Vertical spacing between systems
1001 Space between systems are controlled by four @code{\paper} variables,
1005 between-system-space = 1.5\cm
1006 between-system-padding = #1
1008 ragged-last-bottom=##f
1013 @node Explicit staff and system positioning
1014 @subsection Explicit staff and system positioning
1016 One way to understand the @code{VerticalAxisGroup} and @code{\paper}
1017 settings explained in the previous two sections is as a collection of
1018 different settings that primarily concern the amount of vertical padding
1019 different staves and systems running down the page.
1021 It is possible to approach vertical spacing in a different way using
1022 @code{NonMusicalPaperColumn #'line-break-system-details}. Where
1023 @code{VerticalAxisGroup} and @code{\paper} settings specify vertical padding,
1024 @code{NonMusicalPaperColumn #'line-break-system-details} specifies exact
1025 vertical positions on the page.
1027 @code{NonMusicalPaperColumn #'line-break-system-details} accepts an associative
1028 list of five different settings:
1031 @item @code{X-offset}
1032 @item @code{Y-offset}
1033 @item @code{alignment-offsets}
1034 @item @code{alignment-extra-space}
1035 @item @code{fixed-alignment-extra-space}
1038 Grob overrides, including the overrides for @code{NonMusicalPaperColumn}
1039 below, can occur in any of three different places in an input file:
1042 @item in the middle of note entry directly
1043 @item in a @code{\context} block
1044 @item in the @code{\with} block
1047 When we override @code{NonMusicalPaperColumn}, we use the usual
1048 @code{\override} command in @code{\context} blocks and in the
1049 @code{\with} block. On the other hand, when we override
1050 @code{NonMusicalPaperColumn} in the middle of note entry,
1051 use the special @code{\overrideProperty} command. Here are some
1052 example @code{NonMusicalPaperColumn} overrides with the special
1053 @code{\overrideProperty} command:
1056 \overrideProperty NonMusicalPaperColumn
1057 #'line-break-system-details #'((X-offset . 20))
1059 \overrideProperty NonMusicalPaperColumn
1060 #'line-break-system-details #'((Y-offset . 40))
1062 \overrideProperty NonMusicalPaperColumn
1063 #'line-break-system-details #'((X-offset . 20) (Y-offset . 40))
1065 \override NonMusicalPaperColumn
1066 #'line-break-system-details #'((alignment-offsets . (0 -15)))
1068 \override NonMusicalPaperColumn
1069 #'line-break-system-details #'((X-offset . 20) (Y-offset . 40)
1070 (alignment-offsets . (0 -15)))
1073 To understand how each of these different settings work, we begin
1074 by looking at an example that includes no overrides at all.
1076 @lilypond[quote,ragged-right]
1084 \new Voice { \repeat unfold 18 { c'4 c'4 c'4 c'4 } }
1087 \repeat unfold 18 { d'4 d'4 d'4 d'4 }
1092 This score isolates line- and page-breaking information in a dedicated
1093 voice. This technique of creating a breaks voice will help keep layout
1094 separate from music entry as our example becomes more complicated.
1095 See @ref{Using an extra voice for breaks}.
1097 Explicit @code{\breaks} evenly divide the music into six measures per
1098 line. Vertical spacing results from LilyPond's defaults. To set
1099 the vertical startpoint of each system explicitly, we can set
1100 the @code{Y-offset} pair in the @code{line-break-system-details}
1101 attribute of the @code{NonMusicalPaperColumn} grob:
1103 @lilypond[quote,ragged-right]
1107 \overrideProperty #"Score.NonMusicalPaperColumn"
1108 #'line-break-system-details #'((Y-offset . 0))
1110 \overrideProperty #"Score.NonMusicalPaperColumn"
1111 #'line-break-system-details #'((Y-offset . 40))
1113 \overrideProperty #"Score.NonMusicalPaperColumn"
1114 #'line-break-system-details #'((Y-offset . 80))
1117 \new Voice { \repeat unfold 18 { c'4 c'4 c'4 c'4 } }
1120 \repeat unfold 18 { d'4 d'4 d'4 d'4 }
1125 Note that @code{line-break-system-details} takes an associative list of
1126 potentially many values, but that we set only one value here. Note,
1127 too, that the @code{Y-offset} property here determines the exact vertical
1128 position on the page at which each new system will render.
1130 Now that we have set the vertical startpoint of each system
1131 explicitly, we can also set the vertical startpoint of each staff
1132 within each system manually. We do this using the @code{alignment-offsets}
1133 subproperty of @code{line-break-system-details}.
1135 @lilypond[quote,ragged-right]
1139 \overrideProperty #"Score.NonMusicalPaperColumn"
1140 #'line-break-system-details #'((Y-offset . 20)
1141 (alignment-offsets . (0 -15)))
1143 \overrideProperty #"Score.NonMusicalPaperColumn"
1144 #'line-break-system-details #'((Y-offset . 60)
1145 (alignment-offsets . (0 -15)))
1147 \overrideProperty #"Score.NonMusicalPaperColumn"
1148 #'line-break-system-details #'((Y-offset . 100)
1149 (alignment-offsets . (0 -15)))
1152 \new Voice { \repeat unfold 18 { c'4 c'4 c'4 c'4 } }
1155 \repeat unfold 18 { d'4 d'4 d'4 d'4 }
1160 Note that here we assign two different values to the
1161 @code{line-break-system-details} attribute of the
1162 @code{NonMusicalPaperColumn} grob. Though the
1163 @code{line-break-system-details} attribute alist accepts many
1164 additional spacing parameters (including, for example, a corresponding
1165 @code{X-offset} pair), we need only set the @code{Y-offset} and
1166 @code{alignment-offsets} pairs to control the vertical startpoint of
1167 every system and every staff. Finally, note that @code{alignment-offsets}
1168 specifies the vertical positioning of staves but not of staff groups.
1170 @lilypond[quote,ragged-right]
1174 \overrideProperty #"Score.NonMusicalPaperColumn"
1175 #'line-break-system-details #'((Y-offset . 0)
1176 (alignment-offsets . (0 -30 -40)))
1178 \overrideProperty #"Score.NonMusicalPaperColumn"
1179 #'line-break-system-details #'((Y-offset . 60)
1180 (alignment-offsets . (0 -10 -20)))
1182 \overrideProperty #"Score.NonMusicalPaperColumn"
1183 #'line-break-system-details #'((Y-offset . 100)
1184 (alignment-offsets . (0 -10, -40)))
1187 \new Voice { \repeat unfold 18 { c'4 c'4 c'4 c'4 } }
1191 \repeat unfold 18 { d'4 d'4 d'4 d'4 }
1194 \repeat unfold 18 { e'4 e'4 e'4 e'4 }
1200 Some points to consider:
1203 @item When using @code{alignment-offsets}, lyrics count as a staff.
1205 @item The units of the numbers passed to @code{X-offset},
1206 @code{Y-offset} and @code{alignment-offsets} are interpreted as multiples
1207 of the distance between adjacent staff lines. Positive values move staves
1208 and lyrics up, negative values move staves and lyrics down.
1210 @item Because the @code{NonMusicalPaperColumn #'line-break-system-details}
1211 settings given here allow the positioning of staves and systems anywhere
1212 on the page, it is possible to violate paper or margin boundaries or even
1213 to print staves or systems on top of one another. Reasonable values
1214 passed to these different settings will avoid this.
1218 @node Two-pass vertical spacing
1219 @subsection Two-pass vertical spacing
1221 Warning: two-pass vertical spacing is deprecated and will be removed in
1222 a future version of LilyPond. Systems are now stretched automatically
1223 in a single pass. See @ref{Vertical spacing inside a system}.
1225 In order to automatically stretch systems so that they should fill the
1226 space left on a page, a two-pass technique can be used:
1229 @item In the first pass, the amount of vertical space used to increase
1230 the height of each system is computed and dumped to a file.
1231 @item In the second pass, spacing inside the systems are
1232 stretched according to the data in the page layout file.
1235 The @code{ragged-bottom} property adds space between systems, while
1236 the two-pass technique adds space between staves inside a system.
1238 To allow this behaviour, a @code{tweak-key} variable has to be set in
1239 each score @code{\layout} block, and the tweaks included in each score
1240 music, using the @code{\scoreTweak} music function.
1244 %% include the generated page layout file:
1245 \includePageLayoutFile
1250 %% Include this score tweaks:
1251 \scoreTweak "scoreA"
1252 { \clef french c''1 \break c''1 }
1254 \new Staff { \clef soprano g'1 g'1 }
1255 \new Staff { \clef mezzosoprano e'1 e'1 }
1256 \new Staff { \clef alto g1 g1 }
1257 \new Staff { \clef bass c1 c1 }
1260 piece = "Score with tweaks"
1262 %% Define how to name the tweaks for this score:
1263 \layout { #(define tweak-key "scoreA") }
1268 For the first pass, the @code{dump-tweaks} option should be set to
1269 generate the page layout file.
1272 lilypond -dbackend=null -d dump-tweaks <file>.ly
1277 @node Vertical collision avoidance
1278 @subsection Vertical collision avoidance
1280 @funindex outside-staff-priority
1281 @funindex outside-staff-padding
1282 @funindex outside-staff-horizontal-padding
1284 Intuitively, there are some objects in musical notation that belong
1285 to the staff and there are other objects that should be placed outside
1286 the staff. Objects belonging outside the staff include things such as
1287 rehearsal marks, text and dynamic markings (from now on, these will
1288 be called outside-staff objects). LilyPond's rule for the
1289 vertical placement of outside-staff objects is to place them as close
1290 to the staff as possible but not so close that they collide with
1293 LilyPond uses the @code{outside-staff-priority} property to determine
1294 whether a grob is an outside-staff object: if @code{outside-staff-priority}
1295 is a number, the grob is an outside-staff object. In addition,
1296 @code{outside-staff-priority} tells LilyPond in which order the objects
1299 First, LilyPond places all the objects that do not belong outside
1300 the staff. Then it sorts the outside-staff objects according to their
1301 @code{outside-staff-priority} (in increasing order). One by one, LilyPond
1302 takes the outside-staff objects and places them so that they do
1303 not collide with any objects that have already been placed. That
1304 is, if two outside-staff grobs are competing for the same space, the one
1305 with the lower @code{outside-staff-priority} will be placed closer to
1308 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1311 \once \override TextScript #'outside-staff-priority = #1
1312 c4_"Text"\pp % this time the text will be closer to the staff
1314 % by setting outside-staff-priority to a non-number, we
1315 % disable the automatic collision avoidance
1316 \once \override TextScript #'outside-staff-priority = ##f
1317 \once \override DynamicLineSpanner #'outside-staff-priority = ##f
1318 c4_"Text"\pp % now they will collide
1321 The vertical padding between an outside-staff object and the
1322 previously-positioned grobs can be controlled with
1323 @code{outside-staff-padding}.
1325 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1326 \once \override TextScript #'outside-staff-padding = #0
1327 a'^"This text is placed very close to the note"
1328 \once \override TextScript #'outside-staff-padding = #3
1329 c^"This text is padded away from the previous text"
1330 c^"This text is placed close to the previous text"
1333 By default, outside-staff objects are placed without regard to
1334 their horizontal distance from the previously-posititioned grobs. This
1335 can lead to situations in which objects are placed very close to each
1336 other horizontally. Setting @code{outside-staff-horizontal-padding}
1337 causes an object to be offset vertically so that such a situation
1340 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1341 % the markup is too close to the following note
1344 % setting outside-staff-horizontal-padding fixes this
1346 \once \override TextScript #'outside-staff-horizontal-padding = #1
1353 @node Horizontal spacing
1354 @section Horizontal Spacing
1356 @cindex horizontal spacing
1357 @cindex spacing, horizontal
1360 * Horizontal spacing overview::
1361 * New spacing area::
1362 * Changing horizontal spacing::
1364 * Proportional notation::
1368 @node Horizontal spacing overview
1369 @subsection Horizontal spacing overview
1371 The spacing engine translates differences in durations into stretchable
1372 distances (@q{springs}) of differring lengths. Longer durations get
1373 more space, shorter durations get less. The shortest durations get a
1374 fixed amount of space (which is controlled by
1375 @code{shortest-duration-space} in the @internalsref{SpacingSpanner}
1376 object). The longer the duration, the more space it gets: doubling a
1377 duration adds a fixed amount (this amount is controlled by
1378 @code{spacing-increment}) of space to the note.
1380 For example, the following piece contains lots of half, quarter, and
1381 8th notes; the eighth note is followed by 1 note head width (NHW).
1382 The quarter note is followed by 2 NHW, the half by 3 NHW, etc.
1384 @lilypond[quote,fragment,verbatim,relative=1]
1385 c2 c4. c8 c4. c8 c4. c8 c8
1389 Normally, @code{spacing-increment} is set to 1.2 staff space, which is
1390 approximately the width of a note head, and
1391 @code{shortest-duration-space} is set to 2.0, meaning that the
1392 shortest note gets 2.4 staff space (2.0 times the
1393 @code{spacing-increment}) of horizontal space. This space is counted
1394 from the left edge of the symbol, so the shortest notes are generally
1395 followed by one NHW of space.
1397 If one would follow the above procedure exactly, then adding a single
1398 32nd note to a score that uses 8th and 16th notes, would widen up the
1399 entire score a lot. The shortest note is no longer a 16th, but a 32nd,
1400 thus adding 1 NHW to every note. To prevent this, the shortest
1401 duration for spacing is not the shortest note in the score, but rather
1402 the one which occurs most frequently.
1405 The most common shortest duration is determined as follows: in every
1406 measure, the shortest duration is determined. The most common shortest
1407 duration is taken as the basis for the spacing, with the stipulation
1408 that this shortest duration should always be equal to or shorter than
1409 an 8th note. The shortest duration is printed when you run
1410 @code{lilypond} with the @code{--verbose} option.
1412 These durations may also be customized. If you set the
1413 @code{common-shortest-duration} in @internalsref{SpacingSpanner}, then
1414 this sets the base duration for spacing. The maximum duration for this
1415 base (normally an 8th), is set through @code{base-shortest-duration}.
1417 @funindex common-shortest-duration
1418 @funindex base-shortest-duration
1419 @funindex stem-spacing-correction
1422 Notes that are even shorter than the common shortest note are
1423 followed by a space that is proportional to their duration relative to
1424 the common shortest note. So if we were to add only a few 16th notes
1425 to the example above, they would be followed by half a NHW:
1427 @lilypond[quote,fragment,verbatim,relative=2]
1428 c2 c4. c8 c4. c16[ c] c4. c8 c8 c8 c4 c4 c4
1432 In the introduction (see @ref{Engraving}), it was explained that stem
1433 directions influence spacing. This is controlled with the
1434 @code{stem-spacing-correction} property in the
1435 @internalsref{NoteSpacing}, object. These are generated for every
1436 @internalsref{Voice} context. The @code{StaffSpacing} object
1437 (generated in @internalsref{Staff} context) contains the same property
1438 for controlling the stem/bar line spacing. The following example shows
1439 these corrections, once with default settings, and once with
1440 exaggerated corrections:
1442 @lilypond[quote,ragged-right]
1446 \override Staff.NoteSpacing #'stem-spacing-correction = #1.5
1447 \override Staff.StaffSpacing #'stem-spacing-correction = #1.5
1453 Proportional notation is supported; see @ref{Proportional notation}.
1458 Internals: @internalsref{SpacingSpanner}, @internalsref{NoteSpacing},
1459 @internalsref{StaffSpacing}, @internalsref{SeparationItem}, and
1460 @internalsref{SeparatingGroupSpanner}.
1465 There is no convenient mechanism to manually override spacing. The
1466 following work-around may be used to insert extra space into a score.
1468 \once \override Score.SeparationItem #'padding = #1
1471 No work-around exists for decreasing the amount of space.
1474 @node New spacing area
1475 @subsection New spacing area
1477 New sections with different spacing parameters can be started with
1478 @code{newSpacingSection}. This is useful when there are
1479 sections with a different notions of long and short notes.
1481 In the following example, the time signature change introduces a new
1482 section, and hence the 16ths notes are spaced wider.
1484 @lilypond[relative,fragment,verbatim,quote]
1487 c8 c c4 c16[ c c8] c4
1494 The @code{\newSpacingSection} command creates a new
1495 @internalsref{SpacingSpanner} object, and hence new @code{\override}s
1496 may be used in that location.
1499 @node Changing horizontal spacing
1500 @subsection Changing horizontal spacing
1502 Horizontal spacing may be altered with the
1503 @code{base-shortest-duration} property. Here
1504 we compare the same music; once without altering
1505 the property, and then altered. Larger values
1506 of @code{ly:make-moment} will produce smaller
1507 music. Note that @code{ly:make-moment} constructs
1508 a duration, so @code{1 4} is a longer duration
1511 @lilypond[relative,verbatim,line-width=12\cm]
1514 g4 e e2 | f4 d d2 | c4 d e f | g4 g g2 |
1515 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
1516 d4 d d d | d4 e f2 | e4 e e e | e4 f g2 |
1517 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
1522 @lilypond[relative,verbatim,line-width=12\cm]
1525 g4 e e2 | f4 d d2 | c4 d e f | g4 g g2 |
1526 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
1527 d4 d d d | d4 e f2 | e4 e e e | e4 f g2 |
1528 g4 e e2 | f4 d d2 | c4 e g g | c,1 |
1533 \override SpacingSpanner
1534 #'base-shortest-duration = #(ly:make-moment 1 16)
1543 By default, spacing in tuplets depends on various non-duration
1544 factors (such as accidentals, clef changes, etc). To disregard
1545 such symbols and force uniform equal-duration spacing, use
1546 @code{Score.SpacingSpanner #'uniform-stretching}. This
1547 property can only be changed at the beginning of a score,
1549 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1551 \override SpacingSpanner #'uniform-stretching = ##t
1569 When @code{strict-note-spacing} is set, notes are spaced without
1570 regard for clefs, bar lines, and grace notes,
1572 @lilypond[quote,ragged-right,relative=2,fragment,verbatim]
1573 \override Score.SpacingSpanner #'strict-note-spacing = ##t
1574 \new Staff { c8[ c \clef alto c \grace { c16[ c] } c8 c c] c32[ c32] }
1579 @subsection Line length
1582 @cindex breaking pages
1585 @funindex line-width
1586 @funindex ragged-right
1587 @funindex ragged-last
1589 @c Although line-width can be set in \layout, it should be set in paper
1590 @c block, to get page layout right.
1591 @c Setting indent in \paper block makes not much sense, but it works.
1593 @c Bit verbose and vague, use examples?
1594 The most basic settings influencing the spacing are @code{indent} and
1595 @code{line-width}. They are set in the @code{\layout} block. They
1596 control the indentation of the first line of music, and the lengths of
1599 If @code{ragged-right} is set to true in the @code{\layout} block, then
1600 systems ends at their natural horizontal length, instead of being spread
1601 horizontally to fill the whole line. This is useful for
1602 short fragments, and for checking how tight the natural spacing is.
1605 @cindex vertical spacing
1607 The option @code{ragged-last} is similar to @code{ragged-right}, but
1608 only affects the last line of the piece. No restrictions are put on
1609 that line. The result is similar to formatting text paragraphs. In a
1610 paragraph, the last line simply takes its natural horizontal length.
1611 @c Note that for text there are several options for the last line.
1612 @c While Knuth TeX uses natural length, lead typesetters use the same
1613 @c stretch as the previous line. eTeX uses \lastlinefit to
1614 @c interpolate between both these solutions.
1625 @node Proportional notation
1626 @subsection Proportional notation
1628 LilyPond supports proportional notation, a type of horizontal spacing
1629 in which each note consumes an amount of horizontal space exactly
1630 equivalent to its rhythmic duration. This type of proportional spacing
1631 is comparable to horizontal spacing on top of graph paper. Some late
1632 20th- and early 21st-century scores use proportional notation to
1633 clarify complex rhythmic relationships or to faciliate the placement
1634 of timelines or other graphics directly in the score.
1636 LilyPond supports five different settings for proportional notation,
1637 which may be used together or alone:
1640 @item @code{proportionalNotationDuration}
1641 @item @code{uniform-stretching}
1642 @item @code{strict-note-spacing}
1643 @item @code{\remove Separating_line_group_engraver}
1644 @item @code{\override PaperColumn #'used = ##t}
1647 In the examples that follow, we explore these five different
1648 proportional notation settings and examine how these settings interact.
1650 We start with the following one-measure example, which uses classical
1651 spacing with ragged-right turned on.
1653 @lilypond[quote,verbatim,ragged-right]
1655 \new RhythmicStaff {
1659 c'16 c'16 c'16 c'16 c'16
1665 Notice that the half note which begins the measure takes up far less
1666 than half of the horizontal space of the measure. Likewise, the
1667 sixteenth notes and sixteenth-note quintuplets (or twentieth notes)
1668 which end the measure together take up far more than half the
1669 horizontal space of the measure.
1671 In classical engraving, this spacing may be exactly what we want
1672 because we can borrow horizontal space from the half note and conserve
1673 horizontal space across the measure as a whole.
1675 On the other hand, if we want to insert a measured timeline or other
1676 graphic above or below our score, we need proportional notation. We
1677 turn proportional notation on with the proportionalNotationDuration
1680 @lilypond[quote,verbatim,ragged-right]
1682 proportionalNotationDuration = #(ly:make-moment 1 20)
1684 \new RhythmicStaff {
1688 c'16 c'16 c'16 c'16 c'16
1694 The half note at the beginning of the measure and the faster notes in
1695 the second half of the measure now occupy equal amounts of horizontal
1696 space. We could place a measured timeline or graphic above or below
1699 The @code{proportionalNotationDuration} setting is a context setting that
1700 lives in @context{Score}. Recall that context settings appear in one of
1701 three locations in our input file -- in a @code{\with} block, in a
1702 @code{\context} block, or directly in music entry
1703 preceeded by the @code{\set} command. As with all
1704 context settings, users can pick which of the three different
1705 locations they would like to set @code{proportionalNotationDuration}.
1707 The @code{proportionalNotationDuration} setting takes a single argument,
1708 which is the reference duration against which all music will be
1709 spaced. The LilyPond Scheme function make-moment takes two arguments
1710 -- a numerator and denominator which together express some fraction of
1711 a whole note. The call @code{#(ly:make-moment 1 20)} therefore produces a
1712 reference duration of a twentieth note. The values
1713 @code{#(ly:make-moment 1 16)}, @code{#(ly:make-moment 1 8)}, and
1714 @code{#(ly:make-moment 3 97)} are all possible as well.
1716 How do we select the right reference duration to pass to
1717 @code{proportionalNotationDuration}? Usually by a process of trial and error,
1718 beginning with a duration close to the fastest (or smallest) duration
1719 in the piece. Smaller reference durations space music loosely; larger
1720 reference durations space music tightly.
1722 @lilypond[quote,verbatim,ragged-right]
1724 proportionalNotationDuration = #(ly:make-moment 1 8)
1726 \new RhythmicStaff {
1730 c'16 c'16 c'16 c'16 c'16
1736 proportionalNotationDuration = #(ly:make-moment 1 16)
1738 \new RhythmicStaff {
1742 c'16 c'16 c'16 c'16 c'16
1748 proportionalNotationDuration = #(ly:make-moment 1 32)
1750 \new RhythmicStaff {
1754 c'16 c'16 c'16 c'16 c'16
1760 Note that too large a reference duration -- such as the eighth note,
1761 above -- spaces music too tightly and can cause notehead collisions.
1762 Note also that proportional notation in general takes up more
1763 horizontal space that does classical spacing. Proportional spacing
1764 provides rhythmic clarity at the expense of horizontal space.
1766 Next we examine how to optimally space overlapping tuplets.
1768 We start by examining what happens to our original example, with
1769 classical spacing, when we add a second staff with a different type of
1772 @lilypond[quote,verbatim,ragged-right]
1774 \new RhythmicStaff {
1778 c'16 c'16 c'16 c'16 c'16
1781 \new RhythmicStaff {
1783 c'8 c'8 c'8 c'8 c'8 c'8 c'8 c'8 c'8
1789 The spacing is bad because the evenly notes of the bottom staff do not
1790 stretch uniformly. Classical engraving includes very few complex
1791 triplets and so classical engraving rules can generate this type of
1792 result. Setting @code{proportionalNotationDuration} remedies this
1793 situation considerably.
1795 @lilypond[quote,verbatim,ragged-right]
1797 proportionalNotationDuration = #(ly:make-moment 1 20)
1799 \new RhythmicStaff {
1803 c'16 c'16 c'16 c'16 c'16
1806 \new RhythmicStaff {
1808 c'8 c'8 c'8 c'8 c'8 c'8 c'8 c'8 c'8
1814 But if we look very carefully we can see that notes of the second half
1815 of the 9-tuplet space ever so slightly more widely than do the notes
1816 of the first half of the 9-tuplet. To ensure uniform stretching, we
1817 turn on @code{uniform-stretching}, which is a property of
1818 @code{SpacingSpanner}.
1820 @lilypond[quote,verbatim,ragged-right]
1822 proportionalNotationDuration = #(ly:make-moment 1 20)
1823 \override SpacingSpanner #'uniform-stretching = ##t
1825 \new RhythmicStaff {
1829 c'16 c'16 c'16 c'16 c'16
1832 \new RhythmicStaff {
1834 c'8 c'8 c'8 c'8 c'8 c'8 c'8 c'8 c'8
1840 Our two-staff example now spaces exactly, our rhythmic relationships
1841 are visually clear, and we can include a measured timeline or graphic
1844 The @code{SpacingSpanner} is an abstract grob that lives in the
1845 @context{Score} context. As with our settings of
1846 @code{proportionalNotationDuration},
1847 overrides to the @code{SpacingSpanner} can occur in any of three different
1848 places in our input file -- in the Score @code{\with} block, in a
1849 Score @code{\context} block, or in note entry directly.
1851 There is by default only one @code{SpacingSpanner} per @code{Score}. This
1852 means that, by default, @code{uniform-stretching} is either turned on for the
1853 entire score or turned off for the entire score. We can, however,
1854 override this behavior and turn on different spacing features at
1855 different places in the score. We do this with the command
1856 @code{\newSpacingSection}. See @ref{New spacing area}, for more info.
1858 Next we examine the effects of the @code{Separating_line_group_engraver} and
1859 see why proportional scores frequently remove this engraver. The following
1860 example shows that there is a small amount of @qq{preferatory} space
1861 just before the first note in each system.
1863 @lilypond[quote,verbatim,ragged-right]
1876 The amount of this preferatory space is the same whether after a time
1877 signature, a key signature or a clef. @code{Separating_line_group_engraver}
1878 is responsible for this space. Removing @code{Separating_line_group_engraver}
1879 reduces this space to zero.
1881 @lilypond[quote,verbatim,ragged-right]
1887 \remove Separating_line_group_engraver
1895 Nonmusical elements like time signatures, key signatures, clefs and
1896 accidentals are problemmatic in proportional notation. None of these
1897 elements has rhythmic duration. But all of these elements consume
1898 horizontal space. Different proportional scores approach these
1899 problems differently.
1901 It may be possible to avoid spacing problems with key signatures
1902 simply by not having any. This is a valid option since most
1903 proportional scores are contemporary music. The same may be true
1904 of time signatures, especially for those scores
1905 that include a measured timeline or other graphic. But these scores
1906 are exceptional and most proportional scores include at least some
1907 time signatures. Clefs and accidentals are even more essential.
1909 So what strategies exist for spacing nonmusical elements in a
1910 proportional context? One good option is the @code{strict-note-spacing}
1911 property of @code{SpacingSpanner}. Compare the two scores below:
1913 @lilypond[quote,verbatim,ragged-right]
1915 \set Score.proportionalNotationDuration = #(ly:make-moment 1 16)
1925 \set Score.proportionalNotationDuration = #(ly:make-moment 1 16)
1926 \override Score.SpacingSpanner #'strict-note-spacing = ##t
1936 Both scores are proportional, but the spacing in the first score is
1937 too loose because of the clef change. The spacing of the second score
1938 remains strict, however, because @code{strict-note-spacing} is turned
1939 on. Turning on @code{strict-note-spacing} causes the width of time
1940 signatures, key signatures and clefs to play no part in the spacing
1941 algorithm. Accidentals are a different matter, however. By default, all
1942 accidentals consume a little extra space, as the following pair of
1945 @lilypond[quote,verbatim,ragged-right]
1947 \set Score.proportionalNotationDuration = #(ly:make-moment 1 32)
1959 \set Score.proportionalNotationDuration = #(ly:make-moment 1 32)
1971 Both scores are proportional but the second score exhibits spacing
1972 irregularities due to accidentals. Turning on @code{strict-note-spacing}
1973 does not work for accidentals. Instead,
1974 we override the @code{X-extent} of all accidentals to zero and then move the
1975 accidentals to the left of the notes they modify.
1977 @lilypond[quote,verbatim,ragged-right]
1979 \set Score.proportionalNotationDuration = #(ly:make-moment 1 32)
1980 \override Accidental #'X-extent = #'(0 . 0)
1981 \override Accidental #'extra-offset = #'(-1 . 0)
1993 In addition to the settings given here, there are other settings that
1994 frequently appear in proportional scores. These include:
1997 @item @code{\override SpacingSpanner #'strict-grace-spacing = ##t}
1998 @item @code{tupletFullLength = ##t}
1999 @item @code{\override Beam #'breakable = ##t}
2000 @item @code{\override Glissando #'breakable = ##t}
2001 @item @code{\override TextSpanner #'breakable = ##t}
2002 @item @code{\remove Forbid_line_break_engraver in the Voice context}
2005 These settings space grace notes strictly, extend tuplet brackets to
2006 mark both rhythmic start- and stop-points, and allow spanning elements
2007 to break across systems and pages. See the respective parts of the manual
2008 for these related settings.