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13 @chapter Tweaking output
15 This chapter discusses how to modify output. LilyPond is extremely
16 configurable; virtually every fragment of output may be changed.
21 * The Internals Reference manual::
22 * Appearance of objects::
23 * Placement of objects::
24 * Collisions of objects::
29 @section Tweaking basics
32 * Introduction to tweaks::
33 * Objects and interfaces::
34 * Naming conventions of objects and properties::
38 @node Introduction to tweaks
39 @subsection Introduction to tweaks
41 @q{Tweaking} is a LilyPond term for the various methods available
42 to the user for modifying the actions taken during interpretation
43 of the input file and modifying the appearance of the printed
44 output. Some tweaks are very easy to use; others are more
45 complex. But taken together the methods available for tweaking
46 permit almost any desired appearance of the printed music to be
49 In this section we cover the basic concepts required to understand
50 tweaking. Later we give a variety of ready-made commands which can
51 simply be copied to obtain the same effect in your own scores, and
52 at the same time we show how these commands may be constructed so
53 that you may learn how to develop your own tweaks.
55 Before starting on this Chapter you may wish to review the section
56 @ref{Contexts and engravers}, as Contexts, Engravers, and the
57 Properties contained within them are fundamental to understanding
58 and constructing Tweaks.
60 @node Objects and interfaces
61 @subsection Objects and interfaces
67 @cindex properties, object
68 @cindex object properties
70 @cindex object, layout
73 Tweaking involves modifying the internal operation and structures
74 of the LilyPond program, so we must first introduce some terms
75 which are used to describe those internal operations and
78 The term @q{Object} is a generic term used to refer to the
79 multitude of internal structures built by LilyPond during the
80 processing of an input file. So when a command like @code{\new
81 Staff} is encountered a new object of type @code{Staff} is
82 constructed. That @code{Staff} object then holds all the
83 properties associated with that particular staff, for example, its
84 name and its key signature, together with details of the engravers
85 which have been assigned to operate within that staff's context.
86 Similarly, there are objects to hold the properties of all other
87 contexts, such as @code{Voice} objects, @code{Score} objects,
88 @code{Lyrics} objects, as well as objects to represent all
89 notational elements such as bar lines,
90 note heads, ties, dynamics, etc. Every object has its own set of
93 Some types of object are given special names. Objects which represent
94 items of notation on the printed output such as note heads, stems,
95 slurs, ties, fingering, clefs, etc are called @q{Layout objects},
96 often known as @q{Graphical Objects}, or @q{Grobs} for short. These
97 are still objects in the generic sense above, and so they too all have
98 properties associated with them, such as their position, size, color,
101 Some layout objects are still more specialized. Phrasing slurs,
102 crescendo hairpins, ottava marks, and many other grobs are not
103 localized in a single place -- they have a starting point, an
104 ending point, and maybe other properties concerned with their
105 shape. Objects with an extended shape like these are called
108 It remains to explain what @q{Interfaces} are. Many objects, even
109 though they are quite different, share common features which need to
110 be processed in the same way. For example, all grobs have a color, a
111 size, a position, etc, and all these properties are processed in the
112 same way during LilyPond's interpretation of the input file. To
113 simplify these internal operations these common actions and properties
114 are grouped together in an object called a @code{grob-interface}.
115 There are many other groupings of common properties like this, each
116 one given a name ending in @code{interface}. In total there are over
117 100 such interfaces. We shall see later why this is of interest and
120 These, then, are the main terms relating to objects which we
121 shall use in this chapter.
123 @node Naming conventions of objects and properties
124 @subsection Naming conventions of objects and properties
126 @cindex naming conventions for objects
127 @cindex naming conventions for properties
128 @cindex objects, naming conventions
129 @cindex properties, naming conventions
131 We met some object naming conventions previously, in
132 @ref{Contexts and engravers}. Here for reference is a list
133 of the most common object and property types together with
134 the conventions for naming them and a couple of examples of
135 some real names. We have used @q{A} to stand for any capitalized
136 alphabetic character and @q{aaa} to stand for any number of
137 lower-case alphabetic characters. Other characters are used
140 @multitable @columnfractions .33 .33 .33
141 @headitem Object/property type
142 @tab Naming convention
145 @tab Aaaa or AaaaAaaaAaaa
146 @tab Staff, GrandStaff
148 @tab Aaaa or AaaaAaaaAaaa
151 @tab Aaaa_aaa_engraver
152 @tab Clef_engraver, Note_heads_engraver
154 @tab aaa-aaa-interface
155 @tab grob-interface, break-aligned-interface
156 @item Context Properties
157 @tab aaa or aaaAaaaAaaa
158 @tab alignAboveContext, skipBars
159 @item Layout Object Properties
160 @tab aaa or aaa-aaa-aaa
161 @tab direction, beam-thickness
164 As we shall see shortly, the properties of different types of
165 object are modified by different commands, so it is useful to
166 be able to recognize the type of object from the names of its
170 @node Tweaking methods
171 @subsection Tweaking methods
173 @cindex tweaking methods
175 @strong{\override command}
177 @cindex override command
178 @cindex override syntax
183 We have already met the commands @code{\set} and @code{\with}, used to
184 change the properties of @strong{contexts} and to remove and add
185 @strong{engravers}, in @ref{Modifying context properties}, and
186 @ref{Adding and removing engravers}. We now must meet some more
189 The command to change the properties of @strong{layout objects} is
190 @code{\override}. Because this command has to modify
191 internal properties deep within LilyPond its syntax is not
192 as simple as the commands you have met so far. It needs to
193 know precisely which property of which object in which context
194 has to be modified, and what its new value is to be. Let's see
197 The general syntax of this command is:
200 \override @var{Context}.@var{LayoutObject} #'@var{layout-property} =
205 This will set the property with the name @var{layout-property} of the
206 layout object with the name @var{LayoutObject}, which is a member of
207 the @var{Context} context, to the value @var{value}.
209 The @var{Context} can be omitted (and usually is) when the
210 required context is unambiguously implied and is one of lowest
211 level contexts, i.e., @code{Voice}, @code{ChordNames} or
212 @code{Lyrics}, and we shall omit it in many of the following
213 examples. We shall see later when it must be specified.
215 Later sections deal comprehensively with properties and their
216 values, but to illustrate the format and use of these commands
217 we shall use just a few simple properties and values which are
220 For now, don't worry about the @code{#'}, which must precede the
221 layout property, and the @code{#}, which must precede the value.
222 These must always be present in exactly this form. This is the
223 most common command used in tweaking, and most of the rest of
224 this chapter will be directed to presenting examples of how it is
225 used. Here is a simple example to change the color of the
228 @cindex color property, example
229 @cindex NoteHead, example of overriding
231 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
233 \override NoteHead #'color = #red
235 \override NoteHead #'color = #green
239 @strong{\revert command}
241 @cindex revert command
246 Once overridden, the property retains its new value until it is
247 overridden again or a @code{\revert} command is encountered.
248 The @code{\revert} command has the following syntax and causes
249 the value of the property to revert to its original default
250 value; note, not its previous value if several @code{\override}
251 commands have been issued.
254 \revert @var{Context}.@var{LayoutObject} #'@var{layout-property}
257 Again, just like @var{Context} in the @code{\override} command,
258 @var{Context} is often not needed. It will be omitted
259 in many of the following examples. Here we revert the color
260 of the note head to the default value for the final two notes:
262 @cindex color property, example
263 @cindex NoteHead, example of overriding
265 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
267 \override NoteHead #'color = #red
269 \override NoteHead #'color = #green
271 \revert NoteHead #'color
275 @strong{\once prefix}
280 Both the @code{\override} and the @code{\set} commands may be
281 prefixed by @code{\once}. This causes the following
282 @code{\override} or @code{\set} command to be effective only
283 during the current musical moment before the property reverts
284 back to its default value. Using the same example, we can
285 change the color of a single note like this:
287 @cindex color property, example
288 @cindex NoteHead, example of overriding
290 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
292 \once \override NoteHead #'color = #red
294 \once \override NoteHead #'color = #green
298 @strong{\overrideProperty command}
300 @cindex overrideProperty command
302 @funindex \overrideProperty
303 @funindex overrideProperty
305 There is another form of the override command,
306 @code{\overrideProperty}, which is occasionally required.
307 We mention it here for completeness, but for details see
308 @ruser{Difficult tweaks}.
309 @c Maybe explain in a later iteration -td
311 @strong{\tweak command}
313 @cindex tweak command
318 The final tweaking command which is available is @code{\tweak}.
319 This should be used to change the properties of objects which
320 occur at the same musical moment, such as the notes within a
321 chord. Using @code{\override} would affect all the notes
322 within a chord, whereas @code{\tweak} affects just the following
323 item in the input stream.
325 Here's an example. Suppose we wish to change the size of the
326 middle note head (the E) in a C major chord. Let's first see what
327 @code{\once \override} would do:
329 @cindex font-size property, example
330 @cindex NoteHead, example of overriding
332 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
334 \once \override NoteHead #'font-size = #-3
339 We see the override affects @emph{all} the note heads in the chord.
340 This is because all the notes of a chord occur at the same
341 @emph{musical moment}, and the action of @code{\once} is to
342 apply the override to all layout objects of the type specified
343 which occur at the same musical moment as the @code{\override}
346 The @code{\tweak} command operates in a different way. It acts
347 on the immediately following item in the input stream. However,
348 it is effective only on objects which are created directly from
349 the input stream, essentially note heads and articulations;
350 objects such as stems and accidentals are created later and
351 cannot be tweaked in this way. Furthermore, when it is applied
352 to note heads these @emph{must} be within a chord, i.e., within
353 single angle brackets, so to tweak a single note the @code{\tweak}
354 command must be placed inside single angle brackets with the
357 So to return to our example, the size of the middle note of
358 a chord would be changed in this way:
360 @cindex font-size property, example
361 @cindex @code{\tweak}, example
363 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
365 <c \tweak #'font-size #-3 e g>4
368 Note that the syntax of @code{\tweak} is different from that
369 of the @code{\override} command. Neither the context nor the
370 layout object should be specified; in fact, it would generate
371 an error to do so. These are both implied by the following
372 item in the input stream. So the general syntax of the
373 @code{\tweak} command is simply
376 \tweak #'@var{layout-property} = #@var{value}
379 A @code{\tweak} command can also be used to modify just one in
380 a series of articulations, as shown here:
382 @cindex color property, example
383 @cindex @code{\tweak}, example
385 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
387 -\tweak #'color #red ^Red
388 -\tweak #'color #green _Green
392 Note that the @code{\tweak} command must be preceded by an
393 articulation mark as if it were an articulation itself.
395 @cindex tuplets, nested
396 @cindex triplets, nested
397 @cindex bracket, tuplet
398 @cindex tuplet bracket
399 @cindex triplet bracket
401 @funindex TupletBracket
403 The @code{\tweak} command must also be used to change the
404 appearance of one of a set of nested tuplets which begin at the
405 same musical moment. In the following example, the long tuplet
406 bracket and the first of the three short brackets begin at the
407 same musical moment, so any @code{\override} command would apply
408 to both of them. In the example, @code{\tweak} is used to
409 distinguish between them. The first @code{\tweak} command
410 specifies that the long tuplet bracket is to be placed above the
411 notes and the second one specifies that the tuplet number is to be
412 printed in red on the first short tuplet bracket.
414 @cindex @code{\tweak}, example
415 @cindex direction property, example
416 @cindex color property, example
418 @lilypond[quote,ragged-right,verbatim,fragment,relative=2]
419 \tweak #'direction #up
422 \times 2/3 { c8[ c8 c8] }
423 \times 2/3 { c8[ c8 c8] }
424 \times 2/3 { c8[ c8 c8] }
428 If nested tuplets do not begin at the same moment, their
429 appearance may be modified in the usual way with
430 @code{\override} commands:
432 @cindex text property, example
433 @cindex tuplet-number function, example
434 @cindex transparent property, example
435 @cindex TupletNumber, example of overriding
437 @c NOTE Tuplet brackets collide if notes are high on staff
439 @lilypond[quote,ragged-right,verbatim,fragment,relative=1]
440 \times 2/3 { c8[ c c]}
441 \once \override TupletNumber
442 #'text = #tuplet-number::calc-fraction-text
446 \once \override TupletNumber #'transparent = ##t
447 \times 2/3 { c8[ c c] }
448 \times 2/3 { c8[ c c]}
455 @ruser{The tweak command}.
458 @node The Internals Reference manual
459 @section The Internals Reference manual
461 @cindex Internals Reference
464 * Properties of layout objects::
465 * Properties found in interfaces::
466 * Types of properties::
469 @node Properties of layout objects
470 @subsection Properties of layout objects
472 @cindex properties of layout objects
473 @cindex properties of grobs
474 @cindex grobs, properties of
475 @cindex layout objects, properties of
476 @cindex Internals Reference manual
478 Suppose you have a slur in a score which, to your mind,
479 appears too thin and you'd like to draw it a little heavier.
480 How do you go about doing this? You know from the statements
481 earlier about the flexibility of LilyPond that such a thing
482 should be possible, and you would probably guess that an
483 @code{\override} command would be needed. But is there a
484 heaviness property for a slur, and if there is, how might it
485 be modified? This is where the Internals Reference manual
486 comes in. It contains all the information you might need to
487 construct this and all other @code{\override} commands.
489 Before we look at the Internals Reference a word of warning.
490 This is a @strong{reference} document, which means there is
491 little or no explanation contained within it: its purpose is
492 to present information precisely and concisely. This
493 means it might look daunting at first sight. Don't worry!
494 The guidance and explanation presented here will enable you
495 to extract the information from the Internals Reference for
496 yourself with just a little practice.
498 @cindex override example
499 @cindex Internals Reference, example of using
500 @cindex @code{\addlyrics} example
502 Let's use a concrete example with a simple fragment of real
505 @lilypond[quote,verbatim,relative=2]
510 g[( e]) e d[( f]) a |
514 The man who feels love's sweet e -- mo -- tion
519 Suppose now that we decide we would like the slurs to be a
520 little heavier. Is this possible? The slur is certainly a
521 layout object, so the question is, @q{Is there a property
522 belonging to a slur which controls the heaviness?} To answer
523 this we must look in the Internals Reference, or IR for short.
525 The IR for the version of LilyPond you are using may be found
526 on the LilyPond website at @uref{http://lilypond.org}. Go to the
527 documentation page and click on the Internals Reference link.
528 For learning purposes you should use the standard HTML version,
529 not the @q{one big page} or the PDF. For the next few
530 paragraphs to make sense you will need to actually do this
533 Under the heading @strong{Top} you will see five links. Select
534 the link to the @emph{Backend}, which is where information about
535 layout objects is to be found. There, under the heading
536 @strong{Backend}, select the link to @emph{All layout objects}.
537 The page that appears lists all the layout objects used in your
538 version of LilyPond, in alphabetic order. Select the link to
539 Slur, and the properties of Slurs are listed.
541 An alternative way of finding this page is from the Notation
542 Reference. On one of the pages that deals with slurs you may find a
543 link to the Internals Reference. This link will take you directly to
544 this page, but if you have an idea about the name of the layout object
545 to be tweaked, it is easier to go straight to the IR and search there.
547 This Slur page in the IR tells us first that Slur objects are created
548 by the Slur_engraver. Then it lists the standard settings. Note
549 these are @strong{not} in alphabetic order. Browse down them looking
550 for a property that might control the heaviness of slurs, and you
554 @code{thickness} (number)
556 Line thickness, generally measured in @code{line-thickness}
559 This looks a good bet to change the heaviness. It tells us that
560 the value of @code{thickness} is a simple @emph{number},
561 that the default value is 1.2, and that the units are
562 in another property called @code{line-thickness}.
564 As we said earlier, there are few to no explanations in the IR,
565 but we already have enough information to try changing the
566 slur thickness. We see that the name of the layout object
567 is @code{Slur}, that the name of the property to change is
568 @code{thickness} and that the new value should be a number
569 somewhat larger than 1.2 if we are to make slurs thicker.
571 We can now construct the @code{\override} command by simply
572 substituting the values we have found for the names, omitting
573 the context. Let's use a very large value for the thickness
574 at first, so we can be sure the command is working. We get:
577 \override Slur #'thickness = #5.0
580 Don't forget the @code{#'} preceding the
581 property name and a @code{#} preceding the new value!
583 The final question is, @q{Where should this command be
584 placed?} While you are unsure and learning, the best
585 answer is, @q{Within the music, before the first slur and
586 close to it.} Let's do that:
588 @cindex Slur example of overriding
589 @cindex thickness property, example
591 @lilypond[quote,verbatim,relative=2]
595 % Increase thickness of all following slurs from 1.2 to 5.0
596 \override Slur #'thickness = #5.0
598 g[( e]) e d[( f]) a |
602 The man who feels love's sweet e -- mo -- tion
608 and we see that the slur is indeed heavier.
610 So this is the basic way of constructing @code{\override}
611 commands. There are a few more complications that we
612 shall meet in later sections, but you now know all the
613 essentials required to make up your own -- but you will
614 still need some practice. This is provided in the examples
617 @subheading Finding the context
619 @cindex context, finding
620 @cindex context, identifying correct
622 But first, what if we had needed to specify the Context?
623 What should it be? We could guess that slurs are in
624 the Voice context, as they are clearly closely associated
625 with individual lines of music, but can we be sure? To
626 find out, go back to the top of the IR page describing the
627 Slur, where it says @q{Slur objects are created by: Slur
628 engraver}. So slurs will be created in whichever context
629 the @code{Slur_engraver} is in. Follow the link to the
630 @code{Slur_engraver} page. At the very bottom it tells
631 us that @code{Slur_engraver} is part of five Voice contexts,
632 including the standard voice context, @code{Voice}, so our
633 guess was correct. And because @code{Voice} is one of the
634 lowest level contexts which is implied unambiguously by
635 the fact that we are entering notes, we can omit it in this
638 @subheading Overriding once only
640 @cindex overriding once only
641 @cindex once override
646 As you can see, @emph{all} the slurs are thicker in the final example
647 above. But what if we wanted just the first slur to be thicker? This
648 is achieved with the @code{\once} command. Placed immediately before
649 the @code{\override} command it causes it to change only the slur
650 which begins on the @strong{immediately following} note. If the
651 immediately following note does not begin a slur the command has no
652 effect at all -- it is not remembered until a slur is encountered, it
653 is simply discarded. So the command with @code{\once} must be
654 repositioned as follows:
656 @cindex Slur, example of overriding
657 @cindex thickness property, example
659 @lilypond[quote,verbatim,relative=2]
664 % Increase thickness of immediately following slur only
665 \once \override Slur #'thickness = #5.0
667 g[( e]) e d[( f]) a |
671 The man who feels love's sweet e -- mo -- tion
677 Now only the first slur is made heavier.
679 The @code{\once} command can also be used before the @code{\set}
682 @subheading Reverting
685 @cindex default properties, reverting to
690 Finally, what if we wanted just the first two slurs to be
691 heavier? Well, we could use two commands, each preceded by
692 @code{\once} placed immediately before each of the notes where
695 @cindex Slur, example of overriding
696 @cindex thickness property, example
698 @lilypond[quote,verbatim,relative=2]
703 % Increase thickness of immediately following slur only
704 \once \override Slur #'thickness = #5.0
706 % Increase thickness of immediately following slur only
707 \once \override Slur #'thickness = #5.0
708 g[( e]) e d[( f]) a |
712 The man who feels love's sweet e -- mo -- tion
718 or we could omit the @code{\once} command and use the @code{\revert}
719 command to return the @code{thickness} property to its default value
720 after the second slur:
722 @cindex Slur, example of overriding
723 @cindex thickness property, example
725 @lilypond[quote,verbatim,relative=2]
730 % Increase thickness of all following slurs from 1.2 to 5.0
731 \override Slur #'thickness = #5.0
734 % Revert thickness of all following slurs to default of 1.2
735 \revert Slur #'thickness
740 The man who feels love's sweet e -- mo -- tion
746 The @code{\revert} command can be used to return any property
747 changed with @code{\override} back to its default value.
748 You may use whichever method best suits what you want to do.
750 That concludes our introduction to the IR, and the basic
751 method of tweaking. Several examples follow in the later
752 sections of this Chapter, partly to introduce you to some of the
753 additional features of the IR, and partly to give you more
754 practice in extracting information from it. These examples will
755 contain progressively fewer words of guidance and explanation.
758 @node Properties found in interfaces
759 @subsection Properties found in interfaces
762 @cindex interface properties
763 @cindex properties in interfaces
765 Suppose now that we wish to print the lyrics in italics. What form of
766 @code{\override} command do we need to do this? We first look in the
767 IR page listing @q{All layout objects}, as before, and look for an
768 object that might control lyrics. We find @code{LyricText}, which
769 looks right. Clicking on this shows the settable properties for lyric
770 text. These include the @code{font-series} and @code{font-size}, but
771 nothing that might give an italic shape. This is because the shape
772 property is one that is common to all font objects, so, rather than
773 including it in every layout object, it is grouped together with other
774 similar common properties and placed in an @strong{Interface}, the
775 @code{font-interface}.
777 So now we need to learn how to find the properties of interfaces,
778 and to discover what objects use these interface properties.
780 Look again at the IR page which describes LyricText. At the bottom of
781 the page is a list of clickable interfaces which LyricText supports.
782 The list has several items, including @code{font-interface}. Clicking
783 on this brings up the properties associated with this interface, which
784 are also properties of all the objects which support it, including
787 Now we see all the user-settable properties which control fonts,
788 including @code{font-shape(symbol)}, where @code{symbol} can be
789 set to @code{upright}, @code{italics} or @code{caps}.
791 You will notice that @code{font-series} and @code{font-size} are also
792 listed there. This immediately raises the question: Why are the
793 common font properties @code{font-series} and @code{font-size} listed
794 under @code{LyricText} as well as under the interface
795 @code{font-interface} but @code{font-shape} is not? The answer is
796 that @code{font-series} and @code{font-size} are changed from their
797 global default values when a @code{LyricText} object is created, but
798 @code{font-shape} is not. The entries in @code{LyricText} then tell
799 you the values for those two properties which apply to
800 @code{LyricText}. Other objects which support @code{font-interface}
801 will set these properties differently when they are created.
803 Let's see if we can now construct the @code{\override} command
804 to change the lyrics to italics. The object is @code{LyricText},
805 the property is @code{font-shape} and the value is
806 @code{italic}. As before, we'll omit the context.
808 As an aside, although it is an important one, note that because the
809 values of @code{font-shape} are symbols they must be introduced with a
810 single apostrophe, @code{'}. That is why apostrophes are needed
811 before @code{thickness} in the earlier example and @code{font-shape}.
812 These are both symbols too. Symbols are then read internally by
813 LilyPond. Some of them are the names of properties, like
814 @code{thickness} or @code{font-shape}, others are used as values that
815 can be given to properties, like @code{italic}. Note the distinction
816 from arbitrary text strings, which would appear as @code{"a text
817 string"}; for more details about symbols and strings, see @ref{Scheme
820 Ok, so the @code{\override} command we need to print the lyrics
824 \override LyricText #'font-shape = #'italic
828 and this should be placed just in front of and close to the
829 lyrics which it should affect, like this:
831 @cindex font-shape property, example
832 @cindex italic, example
833 @cindex LyricText, example of overriding
834 @cindex @code{\addlyrics}, example
836 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
841 g[( e]) e d[( f]) a |
845 \override LyricText #'font-shape = #'italic
846 The man who feels love's sweet e -- mo -- tion
852 and the lyrics are all printed in italics.
854 @subheading Specifying the context in lyric mode
856 @cindex context, specifying in lyric mode
857 @cindex lyric mode, specifying context
859 In the case of lyrics, if you try specifying the context in the
860 format given earlier the command will fail. A syllable
861 entered in lyricmode is terminated by either a space,
862 a newline or a digit. All other characters are included
863 as part of the syllable. For this reason a space or newline
864 must appear before the terminating @code{@}} to prevent it being
865 included as part of the final syllable. Similarly,
866 spaces must be inserted before and after the
867 period or dot, @q{.}, separating the context name from the
868 object name, as otherwise the two names are run together and
869 the interpreter cannot recognize them. So the command should be:
872 \override Lyrics . LyricText #'font-shape = #'italic
875 @warning{In lyrics always leave whitespace between the final
876 syllable and the terminating brace.}
878 @warning{In overrides in lyrics always place spaces around
879 the dot between the context name and the object name.}
883 Learning Manual: @ref{Scheme tutorial}.
886 @node Types of properties
887 @subsection Types of properties
889 @cindex property types
891 So far we have seen two types of property: @code{number} and
892 @code{symbol}. To be valid, the value given to a property
893 must be of the correct type and obey the rules for that type.
894 The type of property is always shown in brackets after the
895 property name in the IR. Here is a list of the types you may
896 need, together with the rules for that type, and some examples.
897 You must always add a hash symbol, @code{#}, of course,
898 to the front of these values when they are entered in the
899 @code{\override} command.
901 @multitable @columnfractions .2 .45 .35
902 @headitem Property type
906 @tab Either True or False, represented by #t or #f
907 @tab @code{#t}, @code{#f}
908 @item Dimension (in staff space)
909 @tab A positive decimal number (in units of staff space)
910 @tab @code{2.5}, @code{0.34}
912 @tab A valid direction constant or its numerical equivalent (decimal
913 values between -1 and 1 are allowed)
914 @tab @code{LEFT}, @code{CENTER}, @code{UP},
917 @tab A positive whole number
918 @tab @code{3}, @code{1}
920 @tab A set of values separated by spaces, enclosed in parentheses
921 and preceded by an apostrophe
922 @tab @code{'(left-edge staff-bar)}, @code{'(1)},
923 @code{'(1.0 0.25 0.5)}
925 @tab Any valid markup
926 @tab @code{\markup @{ \italic "cresc." @}}
928 @tab A fraction of a whole note constructed with the
930 @tab @code{(ly:make-moment 1 4)},
931 @code{(ly:make-moment 3 8)}
933 @tab Any positive or negative decimal value
934 @tab @code{3.5}, @code{-2.45}
935 @item Pair (of numbers)
936 @tab Two numbers separated by a @q{space . space} and enclosed
937 in brackets preceded by an apostrophe
938 @tab @code{'(2 . 3.5)}, @code{'(0.1 . -3.2)}
940 @tab Any of the set of permitted symbols for that property,
941 preceded by an apostrophe
942 @tab @code{'italic}, @code{'inside}
944 @tab A procedure, or @code{#f} to cause no action
945 @tab @code{bend::print}, @code{ly:text-interface::print},
948 @tab A list of three items enclosed in parentheses and preceded
949 by apostrophe-hash, @code{'#}.
950 @tab @code{'#(#t #t #f)}
955 Learning Manual: @ref{Scheme tutorial}.
958 @node Appearance of objects
959 @section Appearance of objects
961 Let us now put what we have learned into practice with a few
962 examples which show how tweaks may be used to change the
963 appearance of the printed music.
966 * Visibility and color of objects::
968 * Length and thickness of objects::
971 @node Visibility and color of objects
972 @subsection Visibility and color of objects
974 In the educational use of music we might wish to print a score
975 with certain elements omitted as an exercise for the student,
976 who is required to supply them. As a simple example,
977 let us suppose the exercise is to supply the missing bar lines
978 in a piece of music. But the bar lines are normally inserted
979 automatically. How do we prevent them printing?
981 Before we tackle this, let us remember that object properties are
982 grouped in what are called @emph{interfaces} -- see @ref{Properties
983 found in interfaces}. This is simply to group together those
984 properties that may be used together to tweak a graphical object -- if
985 one of them is allowed for an object, so are the others. Some objects
986 then use the properties in some interfaces, others use them from other
987 interfaces. The interfaces which contain the properties used by a
988 particular grob are listed in the IR at the bottom of the page
989 describing that grob, and those properties may be viewed by looking at
992 We explained how to find information about grobs in @ref{Properties of
993 layout objects}. Using the same approach, we go to the IR to find the
994 layout object which prints bar lines. Going via @emph{Backend} and
995 @emph{All layout objects} we find there is a layout object called
996 @code{BarLine}. Its properties include two that control its
997 visibility: @code{break-visibility} and @code{stencil}. Barline also
998 supports a number of interfaces, including the @code{grob-interface},
999 where we find the @code{transparent} and the @code{color} properties.
1000 All of these can affect the visibility of bar lines (and, of course,
1001 by extension, many other layout objects too.) Let's consider each of
1006 @cindex stencil property
1008 This property controls the appearance of the bar lines by specifying
1009 the symbol (glyph) which should be printed. In common
1010 with many other properties, it can be set to print nothing by
1011 setting its value to @code{#f}. Let's try it, as before, omitting
1012 the implied Context, @code{Voice}:
1014 @cindex BarLine, example of overriding
1015 @cindex stencil property, example
1017 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1020 \override BarLine #'stencil = ##f
1022 g, a16 b8 c d4 e16 |
1027 The bar lines are still printed. What is wrong? Go back to the IR
1028 and look again at the page giving the properties of BarLine. At the
1029 top of the page it says @qq{Barline objects are created by:
1030 Bar_engraver}. Go to the @code{Bar_engraver} page. At the bottom it
1031 gives a list of Contexts in which the bar engraver operates. All of
1032 them are of the type @code{Staff}, so the reason the @code{\override}
1033 command failed to work as expected is because @code{Barline} is not in
1034 the default @code{Voice} context. If the context is specified
1035 wrongly, the command simply does not work. No error message is
1036 produced, and nothing is logged in the log file. Let's try correcting
1037 it by adding the correct context:
1039 @cindex BarLine, example of overriding
1040 @cindex stencil property, example
1042 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1045 \override Staff.BarLine #'stencil = ##f
1047 g, a16 b8 c d4 e16 |
1052 Now the bar lines have vanished.
1054 @subheading break-visibility
1056 @cindex break-visibility property
1058 We see from the @code{BarLine} properties in the IR that the
1059 @code{break-visibility} property requires a vector of three booleans.
1060 These control respectively whether bar lines are printed at the end of
1061 a line, in the middle of lines, and at the beginning of lines. For
1062 our example we want all bar lines to be suppressed, so the value we
1063 need is @code{'#(#f #f #f)}. Let's try that, remembering to include
1064 the @code{Staff} context. Note also that in writing this value we
1065 have @code{#'#} before the opening bracket. The @code{'#} is required
1066 as part of the value to introduce a vector, and the first @code{#} is
1067 required, as always, to precede the value itself in the
1068 @code{\override} command.
1070 @cindex BarLine, example of overriding
1071 @cindex break-visibility property, example
1073 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1076 \override Staff.BarLine #'break-visibility = #'#(#f #f #f)
1078 g, a16 b8 c d4 e16 |
1083 And we see this too removes all the bar lines.
1085 @subheading transparent
1087 @cindex transparent property
1088 @cindex transparency
1090 We see from the properties specified in the @code{grob-interface} page
1091 in the IR that the @code{transparent} property is a boolean. This
1092 should be set to @code{#t} to make the grob transparent. In this next
1093 example let us make the time signature invisible rather than the bar
1094 lines. To do this we need to find the grob name for the time
1095 signature. Back to the @q{All layout objects} page in the IR to find
1096 the properties of the @code{TimeSignature} layout object. This is
1097 produced by the @code{Time_signature_engraver} which you can check
1098 also lives in the @code{Staff} context and also supports the
1099 @code{grob-interface}. So the command to make the time signature
1102 @cindex TimeSignature, example of overriding
1103 @cindex transparent property, example
1105 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1108 \override Staff.TimeSignature #'transparent = ##t
1110 g, a16 b8 c d4 e16 |
1116 The time signature is gone, but this command leaves a gap where
1117 the time signature should be. Maybe this is what is wanted for
1118 an exercise for the student to fill it in, but in other
1119 circumstances a gap might be undesirable. To remove it, the
1120 stencil for the time signature should be set to @code{#f}
1123 @cindex TimeSignature, example of overriding
1124 @cindex stencil property, example
1126 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1129 \override Staff.TimeSignature #'stencil = ##f
1131 g, a16 b8 c d4 e16 |
1137 and the difference is obvious: setting the stencil to @code{#f}
1138 removes the object entirely; making the object @code{transparent}
1139 leaves it where it is, but makes it invisible.
1143 @cindex color property
1145 Finally let us try making the bar lines invisible by coloring
1146 them white. (There is a difficulty with this in that the
1147 white bar line may or may not blank out the staff lines where
1148 they cross. You may see in some of the examples below that this
1149 happens unpredictably. The details of why this is so and how to
1150 control it are covered in @ruser{Painting objects white}. But at
1151 the moment we are learning about color, so please just accept this
1152 limitation for now.)
1154 The @code{grob-interface} specifies that the
1155 color property value is a list, but there is no
1156 explanation of what that list should be. The list it
1157 requires is actually a list of values in internal units,
1158 but, to avoid having to know what these are, several ways
1159 are provided to specify colors. The first way is to use one
1160 of the @q{normal} colors listed in the first table in
1161 @ruser{List of colors}. To set the bar lines to white
1164 @cindex BarLine, example of overriding
1165 @cindex color property, example
1167 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1170 \override Staff.BarLine #'color = #white
1172 g, a16 b8 c d4 e16 |
1178 and again, we see the bar lines are not visible. Note that
1179 @emph{white} is not preceded by an apostrophe -- it is not
1180 a symbol, but a @emph{function}. When called, it provides
1181 the list of internal values required to set the color to
1182 white. The other colors in the normal list are functions
1183 too. To convince yourself this is working you might like
1184 to change the color to one of the other functions in the
1192 The second way of changing the color is to use the list of
1193 X11 color names in the second list in @ruser{List of colors}.
1194 However, these must be preceded by another function, which
1195 converts X11 color names into the list of internal values,
1196 @code{x11-color}, like this:
1198 @cindex BarLine, example of overriding
1199 @cindex color property, example
1201 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1204 \override Staff.BarLine #'color = #(x11-color 'white)
1206 g, a16 b8 c d4 e16 |
1212 Note that in this case the function @code{x11-color} takes
1213 a symbol as an argument, so the symbol must be preceded by
1214 an apostrophe and the two enclosed in brackets.
1221 There is yet a third function, one which converts RGB values into
1222 internal colors -- the @code{rgb-color} function. This takes
1223 three arguments giving the intensities of the red, green and
1224 blue colors. These take values in the range 0 to 1. So to
1225 set the color to red the value should be @code{(rgb-color 1 0 0)}
1226 and to white it should be @code{(rgb-color 1 1 1)}:
1228 @cindex BarLine, example of overriding
1229 @cindex color property, example
1231 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1234 \override Staff.BarLine #'color = #(rgb-color 1 1 1)
1236 g, a16 b8 c d4 e16 |
1241 Finally, there is also a grey scale available as part of the
1242 X11 set of colors. These range from black, @code{'grey0'},
1243 to white, @code{'grey100}, in steps of 1. Let's illustrate
1244 this by setting all the layout objects in our example to
1245 various shades of grey:
1247 @cindex StaffSymbol, example of overriding
1248 @cindex TimeSignature, example of overriding
1249 @cindex Clef, example of overriding
1250 @cindex NoteHead, example of overriding
1251 @cindex Stem, example of overriding
1252 @cindex BarLine, example of overriding
1253 @cindex color property, example
1254 @cindex x11-color, example of using
1256 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1259 \override Staff.StaffSymbol #'color = #(x11-color 'grey30)
1260 \override Staff.TimeSignature #'color = #(x11-color 'grey60)
1261 \override Staff.Clef #'color = #(x11-color 'grey60)
1262 \override Voice.NoteHead #'color = #(x11-color 'grey85)
1263 \override Voice.Stem #'color = #(x11-color 'grey85)
1264 \override Staff.BarLine #'color = #(x11-color 'grey10)
1266 g, a16 b8 c d4 e16 |
1272 Note the contexts associated with each of the layout objects.
1273 It is important to get these right, or the commands will not
1274 work! Remember, the context is the one in which the appropriate
1275 engraver is placed. The default context for engravers can be
1276 found by starting from the layout object, going from there to
1277 the engraver which produces it, and on the engraver page in the
1278 IR it tells you in which context the engraver will normally be
1282 @node Size of objects
1283 @subsection Size of objects
1285 @cindex changing size of objects
1286 @cindex size of objects
1287 @cindex objects, size of
1288 @cindex objects, changing size of
1290 Let us begin by looking again at the earlier example
1291 see @ref{Nesting music expressions}) which showed
1292 how to introduce a new temporary staff, as in an @rglos{ossia}.
1294 @cindex alignAboveContext property, example
1295 @cindex @code{\with}, example
1297 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1298 \new Staff ="main" {
1305 alignAboveContext = "main" }
1313 Ossia are normally written without clef and time signature, and
1314 are usually printed slightly smaller than the main staff. We
1315 already know now how to remove the clef and time signature --
1316 we simply set the stencil of each to @code{#f}, as follows:
1318 @cindex alignAboveContext property, example
1319 @cindex @code{\with}, example
1320 @cindex stencil property, example
1321 @cindex Clef, example of overriding
1322 @cindex TimeSignature, example of overriding
1324 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1325 \new Staff ="main" {
1332 alignAboveContext = "main"
1335 \override Staff.Clef #'stencil = ##f
1336 \override Staff.TimeSignature #'stencil = ##f
1346 where the extra pair of braces after the @code{\with} clause are
1347 required to ensure the enclosed overrides and music are applied
1350 But what is the difference between modifying the staff context by
1351 using @code{\with} and modifying the stencils of the clef and the
1352 time signature with \override? The main difference is that
1353 changes made in a @code{\with} clause are made at the time the
1354 context is created, and remain in force as the @strong{default}
1355 values for the duration of that context, whereas
1356 @code{\set} or @code{\override} commands embedded in the
1357 music are dynamic -- they make changes synchronized with
1358 a particular point in the music. If changes are unset or
1359 reverted using @code{\unset} or @code{\revert} they return to
1360 their default values, which will be the ones set in the
1361 @code{\with} clause, or if none have been set there, the normal
1364 Some context properties can be modified only in @code{\with} clauses.
1365 These are those properties which cannot sensibly be changed after the
1366 context has been created. @code{alignAboveContext} and its partner,
1367 @code{alignBelowContext}, are two such properties -- once the staff
1368 has been created its alignment is decided and it would make no sense
1369 to try to change it later.
1371 The default values of layout object properties can also be set
1372 in @code{\with} clauses. Simply use the normal @code{\override}
1373 command leaving out the context name, since this is unambiguously
1374 defined as the context which the @code{\with} clause is modifying.
1375 If fact, an error will be generated if a context is specified
1378 So we could replace the example above with
1380 @cindex alignAboveContext property, example
1381 @cindex @code{\with}, example
1382 @cindex Clef, example of overriding
1383 @cindex TimeSignature, example of overriding
1385 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1386 \new Staff ="main" {
1393 alignAboveContext = "main"
1394 % Don't print clefs in this staff
1395 \override Clef #'stencil = ##f
1396 % Don't print time signatures in this staff
1397 \override TimeSignature #'stencil = ##f
1406 Finally we come to changing the size of layout objects.
1408 Some layout objects are created as glyphs selected from a typeface
1409 font. These include note heads, accidentals, markup, clefs, time
1410 signatures, dynamics and lyrics. Their size is changed by modifying
1411 the @code{font-size} property, as we shall shortly see. Other layout
1412 objects such as slurs and ties -- in general, spanner objects -- are
1413 drawn individually, so there is no @code{font-size} associated with
1414 them. These objects generally derive their size from the objects to
1415 which they are attached, so usually there is no need to change their
1416 size manually. Still other properties such as the length of stems and
1417 bar lines, thickness of beams and other lines, and the separation of
1418 staff lines all need to be modified in special ways.
1420 Returning to the ossia example, let us first change the font-size.
1421 We can do this in two ways. We can either change the size of the
1422 fonts of each object type, like @code{NoteHead}s with commands
1426 \override NoteHead #'font-size = #-2
1429 or we can change the size of all fonts by setting a special
1430 property, @code{fontSize}, using @code{\set}, or by including
1431 it in a @code{\with} clause (but without the @code{\set}).
1437 Both of these statements would cause the font size to be reduced
1438 by 2 steps from its previous value, where each
1439 step reduces or increases the size by approximately 12%.
1441 Let's try it in our ossia example:
1443 @cindex alignAboveContext property, example
1444 @cindex @code{\with}, example
1445 @cindex Clef, example of overriding
1446 @cindex TimeSignature, example of overriding
1447 @cindex fontSize property, example
1449 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1450 \new Staff ="main" {
1457 alignAboveContext = "main"
1458 \override Clef #'stencil = ##f
1459 \override TimeSignature #'stencil = ##f
1460 % Reduce all font sizes by ~24%
1470 This is still not quite right. The note heads and flags are
1471 smaller, but the stems are too long in proportion and the
1472 staff lines are spaced too widely apart. These need to be
1473 scaled down in proportion to the font reduction. The next
1474 sub-section discusses how this is done.
1476 @node Length and thickness of objects
1477 @subsection Length and thickness of objects
1483 @cindex size, changing
1484 @cindex stem length, changing
1485 @cindex staff line spacing, changing
1487 Distances and lengths in LilyPond are generally measured in
1488 staff-spaces, the distance between adjacent lines in the staff,
1489 (or occasionally half staff spaces) while most @code{thickness}
1490 properties are measured in units of an internal property called
1491 @code{line-thickness.} For example, by default, the lines of
1492 hairpins are given a thickness of 1 unit of @code{line-thickness},
1493 while the @code{thickness} of a note stem is 1.3. Note, though,
1494 that some thickness properties are different; for example, the
1495 thickness of beams is measured in staff-spaces.
1497 So how are lengths to be scaled in proportion to the font size?
1498 This can be done with the help of a special function called
1499 @code{magstep} provided for exactly this purpose. It takes
1500 one argument, the change in font size (#-2 in the example above)
1501 and returns a scaling factor suitable for reducing other
1502 objects in proportion. It is used like this:
1504 @cindex alignAboveContext property, example
1505 @cindex @code{\with}, example
1506 @cindex Clef, example of overriding
1507 @cindex TimeSignature, example of overriding
1508 @cindex fontSize property, example
1509 @cindex StaffSymbol, example of overriding
1510 @cindex magstep function, example of using
1511 @cindex staff-space property, example
1512 @cindex stencil property, example
1514 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1515 \new Staff ="main" {
1522 alignAboveContext = "main"
1523 \override Clef #'stencil = ##f
1524 \override TimeSignature #'stencil = ##f
1526 % Reduce stem length and line spacing to match
1527 \override StaffSymbol #'staff-space = #(magstep -2)
1537 Since the length of stems and many other length-related properties are
1538 always calculated relative to the value of the @code{staff-space}
1539 property these are automatically scaled down in length too. Note that
1540 this affects only the vertical scale of the ossia -- the horizontal
1541 scale is determined by the layout of the main music in order to remain
1542 synchronized with it, so it is not affected by any of these changes in
1543 size. Of course, if the scale of all the main music were changed in
1544 this way then the horizontal spacing would be affected. This is
1545 discussed later in the layout section.
1547 This, then, completes the creation of an ossia. The sizes and
1548 lengths of all other objects may be modified in analogous ways.
1550 For small changes in scale, as in the example above, the
1551 thickness of the various drawn lines such as bar lines,
1552 beams, hairpins, slurs, etc does not usually require global
1553 adjustment. If the thickness of any particular layout object
1554 needs to be adjusted this can be best achieved by overriding its
1555 @code{thickness} property. An example of changing the thickness
1556 of slurs was shown above in @ref{Properties of layout objects}.
1557 The thickness of all drawn objects (i.e., those not produced
1558 from a font) may be changed in the same way.
1561 @node Placement of objects
1562 @section Placement of objects
1565 * Automatic behavior::
1566 * Within-staff objects::
1567 * Outside-staff objects::
1571 @node Automatic behavior
1572 @subsection Automatic behavior
1574 @cindex within-staff objects
1575 @cindex outside-staff objects
1576 @cindex objects, within-staff
1577 @cindex objects, outside-staff
1579 There are some objects in musical notation that belong to
1580 the staff and there are other objects that should be
1581 placed outside the staff. These are called within-staff
1582 objects and outside-staff objects respectively.
1584 Within-staff objects are those that are located on the staff
1585 -- note heads, stems, accidentals, etc. The positions of
1586 these are usually fixed by the music itself -- they are
1587 vertically positioned on specific lines of the staff or are
1588 tied to other objects that are so positioned. Collisions of
1589 note heads, stems and accidentals in closely set chords are
1590 normally avoided automatically. There are commands and
1591 overrides which can modify this automatic behavior, as we
1594 Objects belonging outside the staff include things such as
1595 rehearsal marks, text and dynamic markings. LilyPond's rule for
1596 the vertical placement of outside-staff objects is to place them
1597 as close to the staff as possible but not so close that they
1598 collide with any other object. LilyPond uses the
1599 @code{outside-staff-priority} property to determine the order in
1600 which the objects should be placed, as follows.
1602 First, LilyPond places all the within-staff objects.
1603 Then it sorts the outside-staff objects according to their
1604 @code{outside-staff-priority}. The outside-staff objects are
1605 taken one by one, beginning with the object with the lowest
1606 @code{outside-staff-priority}, and placed so that they do not
1607 collide with any objects that have already been placed. That is,
1608 if two outside-staff grobs are competing for the same space, the
1609 one with the lower @code{outside-staff-priority} will be placed
1610 closer to the staff. If two objects have the same
1611 @code{outside-staff-priority} the one encountered first will be
1612 placed closer to the staff.
1614 In the following example all the markup texts have the same
1615 priority (since it is not explicitly set). Note that @q{Text3}
1616 is automatically positioned close to the staff again, nestling
1619 @cindex markup example
1621 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1628 Staves are also positioned, by default, as closely together as
1629 possible (subject to a minimum separation). If notes project
1630 a long way towards an adjacent staff they will force the
1631 staves further apart only if an overlap of the notation
1632 would otherwise occur. The following example demonstrates
1633 this @q{nestling} of the notes on adjacent staves:
1635 @lilypond[quote,ragged-right,verbatim]
1638 \relative c' { c a, }
1641 \relative c'''' { c a, }
1647 @node Within-staff objects
1648 @subsection Within-staff objects
1650 We have already seen how the commands @code{\voiceXXX} affect
1651 the direction of slurs, ties, fingering and
1652 everything else which depends on the direction of the stems.
1653 These commands are essential when writing polyphonic music to
1654 permit interweaving melodic lines to be distinguished.
1655 But occasionally it may be necessary to override this automatic
1656 behavior. This can be done for whole sections of music or even
1657 for an individual note. The property which controls this
1658 behavior is the @code{direction} property of each layout object.
1659 We first explain what this does, and then introduce a number of
1660 ready-made commands which avoid your having to code explicit
1661 overrides for the more common modifications.
1663 Some layout objects like slurs and ties curve, bend or point
1664 either up or down; others like stems and flags also move to
1665 right or left when they point up or down. This is controlled
1666 automatically when @code{direction} is set.
1673 The following example shows in bar 1 the default behavior of stems,
1674 with those on high notes pointing down and those on low notes pointing
1675 up, followed by four notes with all stems forced down, four notes with
1676 all stems forced up, and finally four notes reverted back to the
1679 @cindex Stem, example of overriding
1680 @cindex direction property, example
1682 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1684 \override Stem #'direction = #DOWN
1686 \override Stem #'direction = #UP
1688 \revert Stem #'direction
1692 Here we use the constants @code{DOWN} and @code{UP}.
1693 These have the values @code{-1} and @code{+1} respectively, and
1694 these numerical values may be used instead. The value @code{0}
1695 may also be used in some cases. It is simply treated as meaning
1696 @code{UP} for stems, but for some objects it means @q{center}.
1697 There is a constant, @code{CENTER} which has the value @code{0}.
1699 However, these explicit overrides are not usually used, as there are
1700 simpler equivalent predefined commands available. Here is a table of
1701 the commonest. The meaning of each is stated where it is not obvious.
1703 @multitable @columnfractions .2 .2 .25 .35
1708 @item @code{\arpeggioArrowDown}
1709 @tab @code{\arpeggioArrowUp}
1710 @tab @code{\arpeggioNormal}
1711 @tab Arrow is at bottom, at top, or no arrow
1712 @item @code{\dotsDown}
1714 @tab @code{\dotsNeutral}
1715 @tab Direction of movement to avoid staff lines
1716 @item @code{\dynamicDown}
1717 @tab @code{\dynamicUp}
1718 @tab @code{\dynamicNeutral}
1720 @item @code{\phrasingSlurDown}
1721 @tab @code{\phrasingSlurUp}
1722 @tab @code{\phrasingSlurNeutral}
1723 @tab Note: distinct from slur commands
1724 @item @code{\slurDown}
1726 @tab @code{\slurNeutral}
1728 @item @code{\stemDown}
1730 @tab @code{\stemNeutral}
1732 @item @code{\textSpannerDown}
1733 @tab @code{\textSpannerUp}
1734 @tab @code{\textSpannerNeutral}
1735 @tab Text entered as spanner is below/above staff
1736 @item @code{\tieDown}
1738 @tab @code{\tieNeutral}
1740 @item @code{\tupletDown}
1741 @tab @code{\tupletUp}
1742 @tab @code{\tupletNeutral}
1743 @tab Tuplets are below/above notes
1746 Note that these predefined commands may @strong{not} be
1747 preceded by @code{\once}. If you wish to limit the
1748 effect to a single note you must either use the equivalent
1749 @code{\once \override} command or use the predefined command
1750 followed after the affected note by the corresponding
1751 @code{\xxxNeutral} command.
1753 @subheading Fingering
1755 @cindex fingering, placement
1756 @cindex fingering, chords
1758 The placement of fingering on single notes can also be controlled
1759 by the @code{direction} property, but changing @code{direction}
1760 has no effect on chords. As we shall see, there are special
1761 commands which allow the fingering of individual notes
1762 of chords to be controlled, with the fingering being placed
1763 above, below, to the left or to the right of each note.
1765 First, here's the effect of @code{direction} on the fingering
1766 attached to single notes. The first bar shows the default
1767 behaviour, and the following two bars shows the effect of
1768 specifying @code{DOWN} and @code{UP}:
1770 @cindex Fingering, example of overriding
1771 @cindex direction property, example
1773 @lilypond[quote,verbatim,relative=2]
1775 \override Fingering #'direction = #DOWN
1777 \override Fingering #'direction = #UP
1781 However, overriding the @code{direction} property is not the
1782 easiest way of manually setting the fingering above or below
1783 the notes; using @code{_} or @code{^} instead of @code{-} before
1784 the fingering number is usually preferable. Here is the previous
1785 example using this method:
1787 @cindex fingering example
1789 @lilypond[quote,verbatim,relative=2]
1795 The @code{direction} property is ignored for chords, but the
1796 directional prefixes, @code{_} and @code{^} do work. By default,
1797 the fingering is automatically placed both above and below the
1798 notes of a chord, as shown:
1800 @cindex fingering example
1802 @lilypond[quote,verbatim,relative=2]
1809 but this may be overriden to manually force all or any of the
1810 individual fingering numbers above or below:
1812 @cindex fingering example
1814 @lilypond[quote,verbatim,relative=2]
1820 Even greater control over the placement of fingering of the
1821 individual notes in a chord is possible by using the
1822 @code{\set fingeringOrientations} command. The format of this
1826 @code{\set fingeringOrientations = #'([up] [left/right] [down])}
1830 @code{\set} is used because @code{fingeringOrientations} is a
1831 property of the @code{Voice} context, created and used by the
1832 @code{New_fingering_engraver}.
1834 The property may be set to a list of one to three values.
1835 It controls whether fingerings may be placed above (if
1836 @code{up} appears in the list), below (if @code{down} appears),
1837 to the left (if @code{left} appears, or to the right
1838 (if @code{right} appears). Conversely, if a location is not
1839 listed, no fingering is placed there. LilyPond takes these
1840 constraints and works out the best placement for the fingering
1841 of the notes of the following chords. Note that @code{left} and
1842 @code{right} are mutually exclusive -- fingering may be placed
1843 only on one side or the other, not both.
1845 @warning{To control the placement of the fingering of a single
1846 note using this command it is necessary to write it as a single
1847 note chord by placing angle brackets round it.}
1849 Here are a few examples:
1851 @cindex fingering example
1852 @cindex @code{\set}, example of using
1853 @cindex fingeringOrientations property, example
1855 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1856 \set fingeringOrientations = #'(left)
1858 < c-1 e-2 g-3 b-5 > 4
1859 \set fingeringOrientations = #'(left)
1861 < c-1 e-2 g-3 b-5 > 4
1862 \set fingeringOrientations = #'(up left down)
1864 < c-1 e-2 g-3 b-5 > 4
1865 \set fingeringOrientations = #'(up left)
1867 < c-1 e-2 g-3 b-5 > 4
1868 \set fingeringOrientations = #'(right)
1870 < c-1 e-2 g-3 b-5 > 4
1874 If the fingering seems a little crowded the @code{font-size}
1875 could be reduced. The default value can be seen from the
1876 @code{Fingering} object in the IR to be @code{-5}, so let's
1879 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1880 \override Fingering #'font-size = #-7
1881 \set fingeringOrientations = #'(left)
1883 < c-1 e-2 g-3 b-5 > 4
1884 \set fingeringOrientations = #'(left)
1886 < c-1 e-2 g-3 b-5 > 4
1887 \set fingeringOrientations = #'(up left down)
1889 < c-1 e-2 g-3 b-5 > 4
1890 \set fingeringOrientations = #'(up left)
1892 < c-1 e-2 g-3 b-5 > 4
1893 \set fingeringOrientations = #'(right)
1895 < c-1 e-2 g-3 b-5 > 4
1898 @node Outside-staff objects
1899 @subsection Outside-staff objects
1901 Outside-staff objects are automatically placed to avoid collisions.
1902 Objects with the lower value of the @code{outside-staff-priority}
1903 property are placed nearer to the staff, and other outside-staff
1904 objects are then raised as far as necessary to avoid collisions.
1905 The @code{outside-staff-priority} is defined in the
1906 @code{grob-interface} and so is a property of all layout objects.
1907 By default it is set to @code{#f} for all within-staff objects,
1908 and to a numerical value appropriate to each outside-staff object
1909 when the object is created. The following table shows
1910 the default numerical values for some of the commonest
1911 outside-staff objects which are, by default, placed in the
1912 @code{Staff} or @code{Voice} contexts.
1914 @multitable @columnfractions .3 .3 .3
1915 @headitem Layout Object
1917 @tab Controls position of:
1918 @item @code{MultiMeasureRestText}
1920 @tab Text over full-bar rests
1921 @item @code{TextScript}
1924 @item @code{OttavaBracket}
1926 @tab Ottava brackets
1927 @item @code{TextSpanner}
1930 @item @code{DynamicLineSpanner}
1932 @tab All dynamic markings
1933 @item @code{VoltaBracketSpanner}
1936 @item @code{TrillSpanner}
1938 @tab Spanning trills
1941 Here is an example showing the default placement of some of
1944 @cindex text spanner
1945 @cindex ottava bracket
1947 @funindex \startTextSpan
1948 @funindex startTextSpan
1949 @funindex \stopTextSpan
1950 @funindex stopTextSpan
1952 @cindex TextSpanner, example of overriding
1953 @cindex bound-details property, example
1955 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1956 % Set details for later Text Spanner
1957 \override TextSpanner #'bound-details #'left #'text
1958 = \markup { \small \bold Slower }
1959 % Place dynamics above staff
1961 % Start Ottava Bracket
1966 % Add Dynamic Line Spanner
1972 c\ff c \stopTextSpan
1973 % Stop Ottava Bracket
1978 This example also shows how to create Text Spanners --
1979 text with extender lines above a section of music. The
1980 spanner extends from the @code{\startTextSpan} command to
1981 the @code{\stopTextSpan} command, and the format of the
1982 text is defined by the @code{\override TextSpanner} command.
1983 For more details see @ruser{Text spanners}.
1985 It also shows how ottava brackets are created.
1987 @cindex tweaking bar number placement
1988 @cindex bar numbers, tweaking placement
1989 @cindex tweaking metronome mark placement
1990 @cindex metronome mark, tweaking placement
1991 @cindex tweaking rehearsal mark placement
1992 @cindex rehearsal marks, tweaking placement
1994 Note that bar numbers, metronome marks and rehearsal marks are not
1995 shown. By default these are created in the @code{Score} context and
1996 their @code{outside-staff-priority} is ignored relative to the layout
1997 objects which are created in the @code{Staff} context. If you wish to
1998 place bar numbers, metronome marks or rehearsal marks in accordance
1999 with the value of their @code{outside-staff-priority} the
2000 @code{Bar_number_engraver}, @code{Metronome_mark_engraver} or
2001 @code{Mark_engraver} respectively should be removed from the
2002 @code{Score} context and placed in the top @code{Staff} context. If
2003 this is done, these marks will be given the following default
2004 @code{outside-staff-priority} values:
2006 @multitable @columnfractions .3 .3
2007 @headitem Layout Object @tab Priority
2008 @item @code{RehearsalMark} @tab @code{1500}
2009 @item @code{MetronomeMark} @tab @code{1000}
2010 @item @code{BarNumber} @tab @code{ 100}
2013 If the default values of @code{outside-staff-priority} do not give you
2014 the placing you want, the priority of any of the objects may be
2015 overridden. Suppose we would like the ottava bracket to be placed
2016 below the text spanner in the example above. All we need to do is to
2017 look up the priority of @code{OttavaBracket} in the IR or in the
2018 tables above, and reduce it to a value lower than that of a
2019 @code{TextSpanner}, remembering that @code{OttavaBracket} is created
2020 in the @code{Staff} context:
2022 @cindex TextSpanner, example of overriding
2023 @cindex bound-details property, example
2025 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
2026 % Set details for later Text Spanner
2027 \override TextSpanner #'bound-details #'left #'text
2028 = \markup { \small \bold Slower }
2029 % Place dynamics above staff
2031 %Place following Ottava Bracket below Text Spanners
2032 \once \override Staff.OttavaBracket #'outside-staff-priority = #340
2033 % Start Ottava Bracket
2038 % Add Dynamic Line Spanner
2044 c\ff c \stopTextSpan
2045 % Stop Ottava Bracket
2050 Changing the @code{outside-staff-priority} can also be used to
2051 control the vertical placement of individual objects, although
2052 the results may not always be desirable. Suppose we would
2053 like @qq{Text3} to be placed above @qq{Text4} in the example
2054 under Automatic behavior, above (see @ref{Automatic behavior}).
2055 All we need to do is to look up the priority of @code{TextScript}
2056 in the IR or in the tables above, and increase the priority of
2057 @qq{Text3} to a higher value:
2059 @cindex TextScript, example of overriding
2060 @cindex outside-staff-priority property, example
2062 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2065 \once \override TextScript #'outside-staff-priority = #500
2070 This certainly lifts @qq{Text3} above @qq{Text4} but it also lifts it
2071 above @qq{Text2}, and @qq{Text4} now drops down. Perhaps this is not
2072 so good. What we would really like to do is to position all the
2073 annotation at the same distance above the staff. To do this, we
2074 clearly will need to space the notes out horizontally to make more
2075 room for the text. This is done using the @code{textLengthOn}
2078 @subheading \textLengthOn
2080 @cindex notes, spreading out with text
2082 @funindex \textLengthOn
2083 @funindex textLengthOn
2084 @funindex \textLengthOff
2085 @funindex textLengthOff
2087 By default, text produced by markup takes up no horizontal space
2088 as far as laying out the music is concerned. The @code{\textLengthOn}
2089 command reverses this behavior, causing the notes to be spaced
2090 out as far as is necessary to accommodate the text:
2092 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2093 \textLengthOn % Cause notes to space out to accommodate text
2100 The command to revert to the default behavior is
2101 @code{\textLengthOff}. Remember @code{\once} only works with
2102 @code{\override}, @code{\set}, @code{\revert} or @code{unset},
2103 so cannot be used with @code{\textLengthOn}.
2105 @cindex markup text, allowing collisions
2107 Markup text will also avoid notes which project above the staff.
2108 If this is not desired, the automatic displacement upwards may
2109 be turned off by setting the priority to @code{#f}. Here's an
2110 example to show how markup text interacts with such notes.
2112 @cindex TextScript, example of overriding
2113 @cindex outside-staff-priority property, example
2115 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2116 % This markup is short enough to fit without collision
2120 % This is too long to fit, so it is displaced upwards
2124 % Turn off collision avoidance
2125 \once \override TextScript #'outside-staff-priority = ##f
2129 % Turn off collision avoidance
2130 \once \override TextScript #'outside-staff-priority = ##f
2131 \textLengthOn % and turn on textLengthOn
2132 c,,2^"Long Text " % Spaces at end are honored
2137 @subheading Dynamics
2139 @cindex tweaking dynamics placement
2140 @cindex dynamics, tweaking placement
2142 Dynamic markings will normally be positioned beneath the
2143 staff, but may be positioned above with the @code{dynamicUp}
2144 command. They will be positioned vertically relative to the
2145 note to which they are attached, and will float below (or above)
2146 all within-staff objects such as phrasing slurs and bar numbers.
2147 This can give quite acceptable results, as this example
2150 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
2155 bes4.~\f\< \( bes4 bes8 des4\ff\> c16 bes\! |
2156 ees,2.~\)\mf ees4 r8 |
2159 However, if the notes and attached dynamics are close
2160 together the automatic placement will avoid collisions
2161 by displacing later dynamic markings further away, but this may
2162 not be the optimum placement, as this rather artificial example
2165 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2171 Should a similar situation arise in @q{real} music, it may be
2172 preferable to space out the notes a little further, so the dynamic
2173 markings can all fit at the same vertical distance from the staff. We
2174 were able to do this for markup text by using the @code{\textLengthOn}
2175 command, but there is no equivalent command for dynamic marks. So we
2176 shall have to work out how to do this using @code{\override} commands.
2178 @subheading Grob sizing
2181 @cindex sizing grobs
2183 First we must learn how grobs are sized. All grobs have a
2184 reference point defined within them which is used to position
2185 them relative to their parent object. This point in the grob
2186 is then positioned at a horizontal distance, @code{X-offset},
2187 and at a vertical distance, @code{Y-offset}, from its parent.
2188 The horizontal extent of the object is given by a pair of
2189 numbers, @code{X-extent}, which say where the left and right
2190 edges are relative to the reference point. The vertical extent
2191 is similarly defined by a pair of numbers, @code{Y-extent}.
2192 These are properties of all grobs which support the
2193 @code{grob-interface}.
2195 @cindex @code{extra-spacing-width}
2197 By default, outside-staff objects are given a width of zero so
2198 that they may overlap in the horizontal direction. This is done
2199 by the trick of adding infinity to the leftmost extent and
2200 minus infinity to the rightmost extent by setting the
2201 @code{extra-spacing-width} to @code{'(+inf.0 . -inf.0)}. So
2202 to ensure they do not overlap in the horizontal direction we
2203 must override this value of @code{extra-spacing-width} to
2204 @code{'(0 . 0)} so the true width shines through. This is
2205 the command to do this for dynamic text:
2208 \override DynamicText #'extra-spacing-width = #'(0 . 0)
2212 Let's see if this works in our previous example:
2214 @cindex DynamicText, example of overriding
2215 @cindex extra-spacing-width property, example
2217 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2219 \override DynamicText #'extra-spacing-width = #'(0 . 0)
2224 Well, it has certainly stopped the dynamic marks being
2225 displaced, but two problems remain. The marks should be
2226 spaced a little further apart and it would be better
2227 if they were all the same distance from the staff.
2228 We can solve the first problem easily. Instead of making
2229 the @code{extra-spacing-width} zero we could add a little
2230 more to it. The units are the space between two staff
2231 lines, so moving the left edge half a unit to the left and the
2232 right edge half a unit to the right should do it:
2234 @cindex DynamicText, example of overriding
2235 @cindex extra-spacing-width property, example
2237 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2239 % Extend width by 1 staff space
2240 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
2245 This looks better, but maybe we would prefer the dynamic marks
2246 to be aligned along the same baseline rather than going up and
2247 down with the notes. The property to do this is
2248 @code{staff-padding} which is covered in the following section.
2251 @node Collisions of objects
2252 @section Collisions of objects
2256 * Fixing overlapping notation::
2257 * Real music example::
2260 @node Moving objects
2261 @subsection Moving objects
2263 @cindex moving overlapping objects
2264 @cindex moving colliding objects
2265 @cindex moving colliding grobs
2266 @cindex objects, moving colliding
2267 @cindex grobs, moving colliding
2269 This may come as a surprise, but LilyPond is not perfect. Some
2270 notation elements can overlap. This is unfortunate, but in fact
2271 rather rare. Usually the need to move objects is for clarity or
2272 aesthetic reasons -- they would look better with a little more
2273 or a little less space around them.
2275 There are three main approaches to resolving overlapping
2276 notation. They should be considered in the following order:
2280 The @strong{direction} of one of the overlapping objects may
2281 be changed using the predefined commands listed above for
2282 within-staff objects (see @ref{Within-staff objects}).
2283 Stems, slurs, beams, ties, dynamics, text and tuplets may be
2284 repositioned easily in this way. The limitation is that you
2285 have a choice of only two positions, and neither may be
2289 The @strong{object properties}, which LilyPond uses when positioning
2290 layout objects, may be modified using @code{\override}. The
2291 advantages of making changes to this type of property are (a) that
2292 some other objects will be moved automatically if necessary to make
2293 room and (b) the single override can apply to all instances of the
2294 same type of object. Such properties include:
2301 This has already been covered in some detail -- see
2302 @ref{Within-staff objects}.
2305 @code{padding}, @code{left-padding},
2306 @code{right-padding}, @code{staff-padding}
2309 @cindex left-padding property
2310 @cindex padding property
2311 @cindex right-padding property
2312 @cindex staff-padding property
2314 As an object is being positioned the value of its @code{padding}
2315 property specifies the gap that must be left between itself and the
2316 nearest edge of the object against which it is being positioned. Note
2317 that it is the @code{padding} value of the object @strong{being
2318 placed} that is used; the @code{padding} value of the object which is
2319 already placed is ignored. Gaps specified by @code{padding} can be
2320 applied to all objects which support the
2321 @code{side-position-interface}.
2323 Instead of @code{padding}, the placement of groups of accidentals
2324 is controlled by @code{left-padding} and @code{right-padding}.
2325 These properties are to be found in the @code{AccidentalPlacement}
2326 object which, note, lives in the @strong{staff} context. In the
2327 type-setting process the note heads are type-set first and then
2328 the accidentals, if any, are added to the left of the note heads
2329 using the @code{right-padding} property to determine the separation
2330 from the note heads. So only the @code{right-padding} property of the
2331 @code{AccidentalPlacement} object has any effect on the placement
2334 The @code{staff-padding} property is closely related to the
2335 @code{padding} property: @code{padding} controls the minimum amount of
2336 space between any object which supports the
2337 @code{side-position-interface} and the nearest other object (generally
2338 the note or the staff lines); @code{staff-padding} applies only to
2339 those objects which are always set outside the staff -- it controls
2340 the minimum amount of space that should be inserted between that
2341 object and the staff. Note that @code{staff-padding} has no effect on
2342 objects which are positioned relative to the note rather than the
2343 staff, even though it may be overridden without error for such objects
2344 -- it is simply ignored.
2346 To discover which padding property is required for the object you wish
2347 to reposition, you need to return to the IR and look up the object's
2348 properties. Be aware that the padding properties might not be located
2349 in the obvious object, so look in objects that appear to be related.
2351 All padding values are measured in staff spaces. For most
2352 objects, this value is set by default to be around 1.0 or less
2353 (it varies with each object). It may be overridden if a larger
2354 (or smaller) gap is required.
2357 @code{self-alignment-X}
2359 @cindex self-alignment-X property
2361 This property can be used to align the object to the left, to
2362 the right, or to center it with respect to the parent object's
2363 reference point. It may be used with all objects which support
2364 the @code{self-alignment-interface}. In general these are objects
2365 that contain text. The values are @code{LEFT}, @code{RIGHT}
2366 or @code{CENTER}. Alternatively, a numerical value between
2367 @code{-1} and @code{+1} may be specified, where @code{-1} is
2368 left-aligned, @code{+1} is right-aligned, and numbers in between
2369 move the text progressively from left-aligned to right-aligned.
2370 Numerical values greater than @code{1} may be specified to move
2371 the text even further to the left, or less than @code{-1} to
2372 move the text even further to the right. A change of @code{1}
2373 in the value corresponds to a movement of half the text's length.
2376 @code{extra-spacing-width}
2378 @cindex extra-spacing-width property
2380 This property is available for all objects which support the
2381 @code{item-interface}. It takes two numbers, the first is added
2382 to the leftmost extent and the second is added to the rightmost
2383 extent. Negative numbers move the edge to the left, positive to
2384 the right, so to widen an object the first number must be negative,
2385 the second positive. Note that not all objects honor both
2386 numbers. For example, the @code{Accidental} object only takes
2387 notice of the first (left edge) number.
2390 @code{staff-position}
2392 @cindex staff-position property
2394 @code{staff-position} is a property of the
2395 @code{staff-symbol-referencer-interface}, which is supported by
2396 objects which are positioned relative to the staff. It specifies
2397 the vertical position of the object relative to the center line
2398 of the staff in half staff-spaces. It is useful in resolving
2399 collisions between layout objects like multi-measure rests, ties
2400 and notes in different voices.
2405 @cindex force-hshift property
2407 Closely spaced notes in a chord, or notes occurring at the same
2408 time in different voices, are arranged in two, occasionally more,
2409 columns to prevent the note heads overlapping. These are called
2410 note columns, and an object called @code{NoteColumn} is created
2411 to lay out the notes in that column.
2413 The @code{force-hshift} property is a property of a @code{NoteColumn}
2414 (actually of the @code{note-column-interface}). Changing it permits a
2415 note column to be moved in units appropriate to a note column,
2416 viz. the note head width of the first voice note. It should be used
2417 in complex situations where the normal @code{\shiftOn} commands (see
2418 @ref{Explicitly instantiating voices}) do not resolve the note
2419 conflict. It is preferable to the @code{extra-offset} property for
2420 this purpose as there is no need to work out the distance in
2421 staff-spaces, and moving the notes into or out of a @code{NoteColumn}
2422 affects other actions such as merging note heads.
2427 Finally, when all else fails, objects may be manually repositioned
2428 relative to the staff center line vertically, or by displacing them by
2429 any distance to a new position. The disadvantages are that the
2430 correct values for the repositioning have to be worked out, often by
2431 trial and error, for every object individually, and, because the
2432 movement is done after LilyPond has placed all other objects, the user
2433 is responsible for avoiding any collisions that might ensue. But the
2434 main difficulty with this approach is that the repositioning values
2435 may need to be reworked if the music is later modified. The
2436 properties that can be used for this type of manual repositioning are:
2441 @cindex extra-offset property
2443 This property applies to any layout object supporting the
2444 @code{grob-interface}. It takes a pair of numbers which specify the
2445 extra displacement in the horizontal and vertical directions.
2446 Negative numbers move the object to the left or down. The units are
2447 staff-spaces. The extra displacement is made after the typesetting of
2448 objects is finished, so an object may be repositioned anywhere without
2449 affecting anything else.
2453 @cindex positions property
2455 This is most useful for manually adjusting the slope and height
2456 of beams, slurs, and tuplets. It takes a pair of numbers
2457 giving the position of the left and right ends of the beam, slur,
2458 etc. relative to the center line of the staff. Units are
2459 staff-spaces. Note, though, that slurs and phrasing slurs cannot
2460 be repositioned by arbitrarily large amounts. LilyPond first
2461 generates a list of possible positions for the slur and by default
2462 finds the slur that @qq{looks best}. If the @code{positions}
2463 property has been overridden the slur that is closest to the
2464 requested positions is selected from the list.
2469 A particular object may not have all of these properties.
2470 It is necessary to go to the IR to look up which properties
2471 are available for the object in question.
2473 Here is a list of the objects which are most likely to be
2474 involved in collisions, together with the name of the object which
2475 should be looked up in the IR in order to discover which properties
2476 should be used to move them.
2478 @multitable @columnfractions .5 .5
2479 @headitem Object type @tab Object name
2480 @item Articulations @tab @code{Script}
2481 @item Beams @tab @code{Beam}
2482 @item Dynamics (vertically) @tab @code{DynamicLineSpanner}
2483 @item Dynamics (horizontally) @tab @code{DynamicText}
2484 @item Fingerings @tab @code{Fingering}
2485 @item Rehearsal / Text marks @tab @code{RehearsalMark}
2486 @item Slurs @tab @code{Slur}
2487 @item Text e.g. @code{^"text"} @tab @code{TextScript}
2488 @item Ties @tab @code{Tie}
2489 @item Tuplets @tab @code{TupletBracket}
2493 @node Fixing overlapping notation
2494 @subsection Fixing overlapping notation
2496 Let's now see how the properties in the previous section can
2497 help to resolve overlapping notation.
2499 @subheading padding property
2502 @cindex fixing overlapping notation
2503 @cindex overlapping notation
2505 The @code{padding} property can be set to increase
2506 (or decrease) the distance between symbols that are printed
2507 above or below notes.
2509 @cindex Script, example of overriding
2510 @cindex padding property, example
2512 @lilypond[quote,fragment,relative=1,verbatim]
2514 \override Script #'padding = #3
2518 @cindex MetronomeMark, example of overriding
2519 @cindex padding property, example
2521 @lilypond[quote,fragment,relative=1,verbatim]
2522 % This will not work, see below:
2523 \override MetronomeMark #'padding = #3
2527 \override Score.MetronomeMark #'padding = #3
2532 Note in the second example how important it is to figure out what
2533 context handles a certain object. Since the @code{MetronomeMark}
2534 object is handled in the @code{Score} context, property changes in the
2535 @code{Voice} context will not be noticed. For more details, see
2536 @ruser{Modifying properties}.
2538 If the @code{padding} property of an object is increased when that
2539 object is in a stack of objects being positioned according to
2540 their @code{outside-staff-priority}, then that object and all
2541 objects outside it are moved.
2544 @subheading left-padding and right-padding
2546 @cindex left-padding property
2547 @cindex right-padding property
2549 The @code{right-padding} property affects the spacing between the
2550 accidental and the note to which it applies. It is not often
2551 required, but the following example shows one situation where it
2552 is needed. Suppose we wish to show a chord containing both
2553 a B-natural and a B-flat. To avoid ambiguity we would like to
2554 precede the notes with both a natural and a flat sign. Here
2555 are a few attempts to do this:
2557 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2563 None work, with the second two showing bad collisions between
2566 One way of achieving this is to override the accidental stencil
2567 with a markup containing the natural and flat symbols in the
2568 order we would like, like this:
2570 @cindex Accidental, example of overriding
2571 @cindex text property, example
2572 @cindex stencil property, example
2573 @cindex AccidentalPlacement, example of overriding
2574 @cindex right-padding property, example
2576 @lilypond[quote,ragged-right,verbatim]
2577 naturalplusflat = \markup { \natural \flat }
2579 \once \override Accidental
2580 #'stencil = #ly:text-interface::print
2581 \once \override Accidental #'text = #naturalplusflat
2582 \once \override Score.AccidentalPlacement #'right-padding = #1.5
2588 This necessarily uses an override for the accidental stencil which
2589 will not be covered until later. The stencil type must be a
2590 procedure, here changed to print the contents of the @code{text}
2591 property of @code{Accidental}, which itself is set to be a natural
2592 sign followed by a flat sign. These are then moved further away
2593 from the note head by overriding @code{right-padding}.
2597 @subheading staff-padding property
2599 @cindex aligning objects on a baseline
2600 @cindex objects, aligning on a baseline
2602 @code{staff-padding} can be used to align objects such as dynamics
2603 along a baseline at a fixed height above the staff, rather than at a
2604 height dependent on the position of the note to which they are
2605 attached. It is not a property of @code{DynamicText} but of
2606 @code{DynamicLineSpanner}. This is because the baseline should apply
2607 equally to @strong{all} dynamics, including those created as extended
2608 spanners. So this is the way to align the dynamic marks in the
2609 example taken from the previous section:
2611 @cindex DynamicText, example of overriding
2612 @cindex extra-spacing-width property, example
2613 @cindex DynamicLineSpanner, example of overriding
2614 @cindex staff-padding property, example
2616 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2618 % Extend width by 1 unit
2619 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
2620 % Align dynamics to a base line 2 units above staff
2621 \override DynamicLineSpanner #'staff-padding = #2
2626 @subheading self-alignment-X property
2628 The following example shows how this can resolve the collision
2629 of a string fingering object with a note's stem by aligning the
2630 right edge with the reference point of the parent note:
2632 @cindex StringNumber, example of overriding
2633 @cindex self-alignment-X property, example
2635 @lilypond[quote,fragment,ragged-right,verbatim,relative=3]
2638 \once \override StringNumber #'self-alignment-X = #RIGHT
2642 @subheading staff-position property
2644 @cindex object collision within a staff
2646 Multimeasure rests in one voice can collide with notes in another.
2647 Since these rests are typeset centered between the bar lines, it
2648 would require significant effort for LilyPond to figure out which
2649 other notes might collide with it, since all the current collision
2650 handling between notes and between notes and rests is done only
2651 for notes and rests that occur at the same time. Here's an
2652 example of a collision of this type:
2654 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2655 << {c c c c} \\ {R1} >>
2658 The best solution here is to move the multimeasure rest down, since
2659 the rest is in voice two. The default in @code{\voiceTwo} (i.e. in
2660 the second voice of a @code{<<@{...@} \\ @{...@}>>} construct) is that
2661 @code{staff-position} is set to -4 for MultiMeasureRest, so we need to
2662 move it, say, four half-staff spaces down to @code{-8}.
2664 @cindex MultiMeasureRest, example of overriding
2665 @cindex staff-position property, example
2667 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2671 \override MultiMeasureRest #'staff-position = #-8
2676 This is better than using, for example, @code{extra-offset},
2677 because the ledger line above the rest is inserted automatically.
2679 @subheading extra-offset property
2681 @cindex positioning objects
2682 @cindex positioning grobs
2683 @cindex objects, positioning
2684 @cindex grobs, positioning
2686 The @code{extra-offset} property provides complete control over the
2687 positioning of an object both horizontally and vertically.
2689 In the following example, the second fingering is moved a little to
2690 the left, and 1.8 staff space downwards:
2692 @cindex Fingering, example of overriding
2693 @cindex extra-offset property, example
2695 @lilypond[quote,fragment,relative=1,verbatim]
2698 \once \override Fingering
2699 #'extra-offset = #'(-0.3 . -1.8)
2704 @subheading positions property
2706 @cindex controlling tuplets, slurs, phrasing slurs, and beams manually
2707 @cindex manually controlling tuplets, slurs, phrasing slurs, and beams
2708 @cindex tuplet beams, controlling manually
2709 @cindex slurs, controlling manually
2710 @cindex phrasing slurs, controlling manually
2711 @cindex beams, controlling manually
2713 The @code{positions} property allows the position and slope of
2714 tuplets, slurs, phrasing slurs and beams to be controlled manually.
2715 Here's an example which has an ugly phrasing slur due to its trying to
2716 avoid the slur on the acciaccatura.
2718 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2719 r4 \acciaccatura e8\( d8 c ~c d c d\)
2723 We could simply move the phrasing slur above the notes, and this
2724 would be the preferred solution:
2726 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2729 \acciaccatura e8\( d8 c ~c d c d\)
2733 But if there were some reason why this could not be done the
2734 other alternative would be to move the left end of the phrasing
2735 slur down a little using the @code{positions} property. This
2736 also resolves the rather nasty shape.
2738 @cindex PhrasingSlur, example of overriding
2739 @cindex positions property, example
2741 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2743 \once \override PhrasingSlur #'positions = #'(-4 . -3)
2745 e8\( d8 c ~c d c d\)
2748 Here's a further example taken from the opening of the left-hand
2749 staff of Chopin's Prelude Op 28 No. 2. We see that the beam
2750 collides with the upper notes:
2752 @lilypond[quote,verbatim,fragment,ragged-right]
2755 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2756 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2761 This can be resolved by manually moving both ends of the beam
2762 up from their position at 2 staff-spaces above the center line to,
2765 @cindex Beam, example of overriding
2766 @cindex positions property, example
2768 @lilypond[quote,verbatim,fragment,ragged-right]
2772 \override Beam #'positions = #'(3 . 3)
2777 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2782 Note that the override continues to apply in the first voice of
2783 the second block of quavers, but not to any of the beams in the
2786 @subheading force-hshift property
2788 @c FIXME: formatting stuff (ie not important right now IMO)
2789 @c @a nchor Chopin finally corrected TODOgp
2791 We can now see how to apply the final corrections to the Chopin
2792 example introduced at the end of @ref{I'm hearing Voices}, which
2793 was left looking like this:
2795 @lilypond[quote,verbatim,fragment,ragged-right]
2796 \new Staff \relative c'' {
2799 { c2 aes4. bes8 } \\
2811 The lower two notes of the first chord (i.e, those in the third voice)
2812 should not be shifted away from the note column of the higher two
2813 notes. To correct this we set @code{force-hshift}, which is a
2814 property of @code{NoteColumn}, of these notes to zero. The lower note
2815 of the second chord is best placed just to the right of the higher
2816 notes. We achieve this by setting @code{force-hshift} of this note to
2817 0.5, ie half a note head's width to the right of the note column of
2820 Here's the final result:
2822 @cindex NoteColumn, example of overriding
2823 @cindex force-hshift property, example
2825 @lilypond[quote,verbatim,fragment,ragged-right]
2826 \new Staff \relative c'' {
2829 { c2 aes4. bes8 } \\
2832 \once \override NoteColumn #'force-hshift = #0 <ees c>2
2833 \once \override NoteColumn #'force-hshift = #0.5 des2
2841 @node Real music example
2842 @subsection Real music example
2844 We end this section on Tweaks by showing the steps to be taken to
2845 deal with a tricky example which needs several tweaks to produce
2846 the desired output. The example has been deliberately chosen to
2847 illustrate the use of the Notation Reference to resolve unusual
2848 problems with notation. It is not representative of more usual
2849 engraving process, so please do not let these difficulties put
2850 you off! Fortunately, difficulties like these are not very common!
2852 The example is from Chopin's Première Ballade, Op. 23, bars 6 to
2853 9, the transition from the opening Lento to Moderato.
2854 Here, first, is what we want the output to look like, but to avoid
2855 over-complicating the example too much we have left out the
2856 dynamics, fingering and pedalling.
2858 @c The following should appear as music without code
2859 @c This example should not be indexed
2860 @lilypond[quote,ragged-right]
2861 rhMusic = \relative c'' {
2864 \once \override Tie #'staff-position = #3.5
2868 \mergeDifferentlyHeadedOn
2869 \mergeDifferentlyDottedOn
2870 bes2.^\markup {\bold "Moderato"} r8
2872 {c,8[ d fis bes a] | }
2874 % Reposition the c2 to the right of the merged note
2875 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
2876 % Move the c2 out of the main note column so the merge will work
2879 % Stem on the d2 must be down to permit merging
2880 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
2884 \mergeDifferentlyHeadedOff
2885 \mergeDifferentlyDottedOff
2889 lhMusic = \relative c' {
2891 <d g, d>1)\arpeggio |
2898 \new Staff = "RH" <<
2902 \new Staff = "LH" <<
2911 We note first that the right hand part in the third bar
2912 requires four voices. These are the five beamed eighth notes,
2913 the tied C, the half-note D which is merged with the eighth note
2914 D, and the dotted quarter note F-sharp, which is also merged with
2915 the eighth note at the same pitch. Everything else is in a single
2916 voice, so the easiest way is to introduce these four voices
2917 temporarily at the time they are needed. If you have forgotten
2918 how to do this, look at @ref{I'm hearing Voices}. Let us begin
2919 by entering the notes as two variables and setting up the staff
2920 structure in a score block, and see what LilyPond produces by
2923 @lilypond[quote,verbatim,ragged-right]
2924 rhMusic = \relative c'' {
2929 % Start polyphonic section of four voices
2931 {c,8 d fis bes a | }
2942 lhMusic = \relative c' {
2951 \new Staff = "RH" <<
2955 \new Staff = "LH" <<
2964 All the notes are right, but the appearance is far from satisfactory.
2965 The tie clashes with the change in time signature, the beaming in the
2966 third bar is wrong, the notes are not merged together, and several
2967 notation elements are missing. Let's first deal with the easier
2968 things. We can correct the beaming by inserting a beam manually, and
2969 we can easily add the left hand slur and the right hand phrasing slur,
2970 since these were all covered in the Tutorial. Doing this gives:
2972 @lilypond[quote,verbatim,ragged-right]
2973 rhMusic = \relative c'' {
2978 % Start polyphonic section of four voices
2980 {c,8[ d fis bes a] | }
2991 lhMusic = \relative c' {
3000 \new Staff = "RH" <<
3004 \new Staff = "LH" <<
3013 The first bar is now correct. The second bar contains an arpeggio and
3014 is terminated by a double bar line. How do we do these, as they have
3015 not been mentioned in this Learning Manual? This is where we need to
3016 turn to the Notation Reference. Looking up @q{arpeggio} and @q{bar
3017 line} in the index quickly shows us that an arpeggio is produced by
3018 appending @code{\arpeggio} to a chord, and a double bar line is
3019 produced by the @code{\bar "||"} command. That's easily done. We
3020 next need to correct the collision of the tie with the time signature.
3021 This is best done by moving the tie upwards. Moving objects was
3022 covered earlier in @ref{Moving objects}, which says that objects
3023 positioned relative to the staff can be moved by overriding their
3024 @code{staff-position} property, which is specified in half staff
3025 spaces relative to the center line of the staff. So the following
3026 override placed just before the first tied note would move the tie up
3027 to 3.5 half staff spaces above the center line:
3029 @code{\once \override Tie #'staff-position = #3.5}
3031 This completes bar two, giving:
3033 @lilypond[quote,verbatim,ragged-right]
3034 rhMusic = \relative c'' {
3036 \once \override Tie #'staff-position = #3.5
3041 % Start polyphonic section of four voices
3043 {c,8[ d fis bes a] | }
3054 lhMusic = \relative c' {
3056 <d g, d>1)\arpeggio |
3063 \new Staff = "RH" <<
3067 \new Staff = "LH" <<
3076 On to bar three and the start of the Moderato section. The tutorial
3077 showed how to add embolded text with the @code{\markup} command, so
3078 adding @q{Moderato} in bold is easy. But how do we merge notes in
3079 different voices together? This is where we need to turn to the
3080 Notation Reference for help. A search for @qq{merge} in the Notation
3081 Reference index quickly leads us to the commands for merging
3082 differently headed and differently dotted notes in @ruser{Collision
3083 resolution}. In our example we need to merge both types of note for
3084 the duration of the polyphonic section in bar 3, so using the
3085 information we find in the Notation Reference we add
3088 \mergeDifferentlyHeadedOn
3089 \mergeDifferentlyDottedOn
3093 to the start of that section and
3096 \mergeDifferentlyHeadedOff
3097 \mergeDifferentlyDottedOff
3103 @lilypond[quote,verbatim,ragged-right]
3104 rhMusic = \relative c'' {
3106 \once \override Tie #'staff-position = #3.5
3110 bes2.^\markup {\bold "Moderato"} r8
3111 \mergeDifferentlyHeadedOn
3112 \mergeDifferentlyDottedOn
3113 % Start polyphonic section of four voices
3115 {c,8[ d fis bes a] | }
3123 \mergeDifferentlyHeadedOff
3124 \mergeDifferentlyDottedOff
3128 lhMusic = \relative c' {
3130 <d g, d>1)\arpeggio |
3137 \new Staff = "RH" <<
3141 \new Staff = "LH" <<
3150 These overrides have merged the two F-sharp notes, but not the two
3151 on D. Why not? The answer is there in the same section in the
3152 Notation Reference -- notes being merged must have stems in
3153 opposite directions and two notes cannot be merged successfully if
3154 there is a third note in the same note column. Here the two D's
3155 both have upward stems and there is a third note -- the C. We know
3156 how to change the stem direction using @code{\stemDown}, and
3157 the Notation Reference also says how to move the C -- apply a shift
3158 using one of the @code{\shift} commands. But which one?
3159 The C is in voice two which has shift off, and the two D's are in
3160 voices one and three, which have shift off and shift on,
3161 respectively. So we have to shift the C a further level still
3162 using @code{\shiftOnn} to avoid it interfering with the two D's.
3163 Applying these changes gives:
3165 @cindex Tie, example of overriding
3166 @cindex staff-position property, example
3168 @lilypond[quote,verbatim,ragged-right]
3169 rhMusic = \relative c'' {
3171 \once \override Tie #'staff-position = #3.5
3175 bes2.^\markup {\bold "Moderato"} r8
3176 \mergeDifferentlyHeadedOn
3177 \mergeDifferentlyDottedOn
3178 % Start polyphonic section of four voices
3180 {c,8[ d fis bes a] | }
3182 % Move the c2 out of the main note column so the merge will work
3183 {c,8~ \shiftOnn c2 | }
3185 % Stem on the d2 must be down to permit merging
3186 {s8 \stemDown d2 | }
3190 \mergeDifferentlyHeadedOff
3191 \mergeDifferentlyDottedOff
3195 lhMusic = \relative c' {
3197 <d g, d>1)\arpeggio |
3204 \new Staff = "RH" <<
3208 \new Staff = "LH" <<
3217 Nearly there. Only two problems remain: The downward stem on the
3218 merged D should not be there, and the C would be better positioned
3219 to the right of the D's. We know how to do both of these from the
3220 earlier tweaks: we make the stem transparent, and move the C with
3221 the @code{force-hshift} property. Here's the final result:
3223 @cindex NoteColumn, example of overriding
3224 @cindex force-hshift property, example
3225 @cindex Stem, example of overriding
3226 @cindex transparent property, example
3228 @lilypond[quote,verbatim,ragged-right]
3229 rhMusic = \relative c'' {
3232 \once \override Tie #'staff-position = #3.5
3236 bes2.^\markup {\bold "Moderato"} r8
3237 \mergeDifferentlyHeadedOn
3238 \mergeDifferentlyDottedOn
3240 {c,8[ d fis bes a] | }
3242 % Reposition the c2 to the right of the merged note
3243 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
3244 % Move the c2 out of the main note column so the merge will work
3247 % Stem on the d2 must be down to permit merging
3248 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
3252 \mergeDifferentlyHeadedOff
3253 \mergeDifferentlyDottedOff
3257 lhMusic = \relative c' {
3259 <d g, d>1)\arpeggio |
3266 \new Staff = "RH" <<
3270 \new Staff = "LH" <<
3280 @node Further tweaking
3281 @section Further tweaking
3284 * Other uses for tweaks::
3285 * Using variables for tweaks::
3286 * Other sources of information::
3287 * Avoiding tweaks with slower processing::
3288 * Advanced tweaks with Scheme::
3291 @node Other uses for tweaks
3292 @subsection Other uses for tweaks
3294 @cindex transparent property, use of
3295 @cindex objects, making invisible
3296 @cindex removing objects
3297 @cindex objects, removing
3298 @cindex hiding objects
3299 @cindex objects, hiding
3300 @cindex invisible objects
3301 @cindex objects, invisible
3302 @cindex tying notes across voices
3304 @subheading Tying notes across voices
3306 The following example demonstrates how to connect notes in
3307 different voices using ties. Normally, only two notes in the
3308 same voice can be connected with ties. By using two voices,
3309 with the tied notes in one of them
3311 @lilypond[quote,fragment,relative=2]
3312 << { b8~ b8\noBeam }
3318 and blanking the first up-stem in that voice, the tie appears to
3321 @cindex Stem, example of overriding
3322 @cindex transparent property, example
3324 @lilypond[quote,fragment,relative=2,verbatim]
3327 \once \override Stem #'transparent = ##t
3335 To make sure that the just-blanked stem doesn't squeeze the tie
3336 too much, we can lengthen the stem by setting the
3337 @code{length} to @code{8},
3339 @lilypond[quote,fragment,relative=2,verbatim]
3342 \once \override Stem #'transparent = ##t
3343 \once \override Stem #'length = #8
3351 @subheading Simulating a fermata in MIDI
3353 @cindex stencil property, use of
3354 @cindex fermata, implementing in MIDI
3356 For outside-staff objects it is usually better to override the
3357 object's @code{stencil} property rather than its @code{transparent}
3358 property when you wish to remove it from the printed output.
3359 Setting the @code{stencil} property of an object to @code{#f} will
3360 remove that object entirely from the printed output. This means it
3361 has no effect on the placement of other objects placed relative to
3364 For example, if we wished to change the metronome setting in order
3365 to simulate a fermata in the MIDI output we would not want the
3366 metronome markings to appear in the printed output, and we would
3367 not want it to influence the spacing between the two systems or
3368 the positions of adjacent annotations on the staff. So setting
3369 its @code{stencil} property to @code{#f} would be the best way.
3370 We show here the effect of the two methods:
3372 @cindex MetronomeMark, example of overriding
3373 @cindex transparent property, example
3375 @lilypond[quote,verbatim,ragged-right]
3378 % Visible tempo marking
3381 \once \override Score.MetronomeMark #'transparent = ##t
3382 % Invisible tempo marking to lengthen fermata in MIDI
3385 % New tempo for next section
3394 @cindex MetronomeMark, example of overriding
3395 @cindex stencil property, example
3397 @lilypond[quote,verbatim,ragged-right]
3400 % Visible tempo marking
3403 \once \override Score.MetronomeMark #'stencil = ##f
3404 % Invisible tempo marking to lengthen fermata in MIDI
3407 % New tempo for next section
3417 Both methods remove the metronome mark which lengthens the fermata
3418 from the printed output, and both affect the MIDI timing as
3419 required, but the transparent metronome mark in the first line
3420 forces the following tempo indication too high while the
3421 second (with the stencil removed) does not.
3423 @node Using variables for tweaks
3424 @subsection Using variables for tweaks
3426 @cindex variables, using for tweaks
3427 @cindex using variables for tweaks
3428 @cindex tweaks, using variables for
3430 Override commands are often long and tedious to type, and they
3431 have to be absolutely correct. If the same overrides are to be
3432 used many times it may be worth defining variables to hold them.
3433 Suppose we wish to emphasize certain words in lyrics by printing
3434 them in bold italics. The @code{\italic} and @code{\bold}
3435 commands only work within lyrics if they are also embedded in
3436 @code{\markup}, which makes them tedious to enter, so as an
3437 alternative can we instead use the @code{\override} and
3438 @code{\revert} commands?
3441 @code{\override Lyrics . LyricText #'font-shape = #'italic}
3442 @code{\override Lyrics . LyricText #'font-series = #'bold}
3444 @code{\revert Lyrics . LyricText #'font-shape}
3445 @code{\revert Lyrics . LyricText #'font-series}
3448 These would also be extremely tedious to enter if there were many
3449 words requiring emphasis. So instead we define these as two
3450 variables, and use them as follows, although normally we would
3451 perhaps choose shorter names for the variables to make them
3454 @cindex LyricText, example of overriding
3455 @cindex font-shape property, example
3456 @cindex font-series property, example
3458 @lilypond[quote,verbatim]
3460 \override Lyrics . LyricText #'font-shape = #'italic
3461 \override Lyrics . LyricText #'font-series = #'bold
3464 \revert Lyrics . LyricText #'font-shape
3465 \revert Lyrics . LyricText #'font-series
3468 global = { \time 4/4 \partial 4 \key c \major}
3469 SopranoMusic = \relative c' { c4 | e4. e8 g4 g | a a g }
3470 AltoMusic = \relative c' { c4 | c4. c8 e4 e | f f e }
3471 TenorMusic = \relative c { e4 | g4. g8 c4. b8 | a8 b c d e4 }
3472 BassMusic = \relative c { c4 | c4. c8 c4 c | f8 g a b c4 }
3473 VerseOne = \lyrics { E -- | ter -- nal \emphasize Fa -- ther, \normal | strong to save, }
3474 VerseTwo = \lyricmode { O | \emphasize Christ, \normal whose voice the | wa -- ters heard, }
3475 VerseThree = \lyricmode { O | \emphasize Ho -- ly Spi -- rit, \normal | who didst brood }
3476 VerseFour = \lyricmode { O | \emphasize Tri -- ni -- ty \normal of | love and pow'r }
3482 \new Voice = "Soprano" { \voiceOne \global \SopranoMusic }
3483 \new Voice = "Alto" { \voiceTwo \AltoMusic }
3484 \new Lyrics \lyricsto "Soprano" { \VerseOne }
3485 \new Lyrics \lyricsto "Soprano" { \VerseTwo }
3486 \new Lyrics \lyricsto "Soprano" { \VerseThree }
3487 \new Lyrics \lyricsto "Soprano" { \VerseFour }
3491 \new Voice = "Tenor" { \voiceOne \TenorMusic }
3492 \new Voice = "Bass" { \voiceTwo \BassMusic }
3500 @node Other sources of information
3501 @subsection Other sources of information
3503 The Internals Reference documentation contains a lot of information
3504 about LilyPond, but even more information can be gathered by
3505 looking at the internal LilyPond files. To explore these, you must
3506 first find the directory appropriate to your system. The location
3507 of this directory depends (a) on whether you obtained LilyPond
3508 by downloading a precompiled binary from lilypond.org
3509 or whether you installed it from a package manager (i.e.
3510 distributed with Linux, or installed under fink or cygwin) or
3511 compiled it from source, and (b) on which operating system it is
3514 @strong{Downloaded from lilypond.org}
3520 @file{@var{INSTALLDIR}/lilypond/usr/share/lilypond/current/}
3525 @file{@var{INSTALLDIR}/LilyPond.app/Contents/Resources/share/lilypond/current/}
3526 by either @code{cd}-ing into this directory from the
3527 Terminal, or control-clicking on the LilyPond application and
3528 selecting @q{Show Package Contents}.
3532 Using Windows Explorer, navigate to
3533 @file{@var{INSTALLDIR}/LilyPond/usr/share/lilypond/current/}
3537 @strong{Installed from a package manager or compiled from source}
3540 @file{@var{PREFIX}/share/lilypond/@var{X.Y.Z}/}, where
3541 @var{PREFIX} is set by your package manager or @code{configure}
3542 script, and @var{X.Y.Z} is the LilyPond version number.
3546 Within this directory the two interesting subdirectories are
3549 @item @file{ly/} - contains files in LilyPond format
3550 @item @file{scm/} - contains files in Scheme format
3553 Let's begin by looking at some files in @file{ly/}.
3554 Open @file{ly/property-init.ly} in a text editor. The one
3555 you normally use for @code{.ly} files will be fine. This file
3556 contains the definitions of all the standard LilyPond predefined
3557 commands, such as @code{\stemUp} and @code{\slurDotted}. You will
3558 see that these are nothing more than definitions of variables
3559 containing one or a group of @code{\override} commands. For
3560 example, @code{/tieDotted} is defined to be:
3564 \override Tie #'dash-period = #0.75
3565 \override Tie #'dash-fraction = #0.1
3569 If you do not like the default values these predefined commands can
3570 be redefined easily, just like any other variable, at the
3571 head of your input file.
3573 The following are the most useful files to be found in
3576 @multitable @columnfractions .4 .6
3579 @item @file{ly/engraver-init.ly}
3580 @tab Definitions of engraver Contexts
3581 @item @file{ly/paper-defaults-init.ly}
3582 @tab Specifications of paper-related defaults
3583 @item @file{ly/performer-init.ly}
3584 @tab Definitions of performer Contexts
3585 @item @file{ly/property-init.ly}
3586 @tab Definitions of all common predefined commands
3587 @item @file{ly/spanner-init.ly}
3588 @tab Definitions of spanner-related predefined commands
3591 Other settings (such as the definitions of markup commands) are
3592 stored as @code{.scm} (Scheme) files. The Scheme programming
3593 language is used to provide a programmable interface into
3594 LilyPond internal operation. Further explanation of these files
3595 is currently outside the scope of this manual, as a knowledge of
3596 the Scheme language is required. Users should be warned that
3597 a substantial amount of technical knowledge or time is required
3598 to understand Scheme and these files (see @ref{Scheme tutorial}).
3600 If you have this knowledge, the Scheme files which may be of
3603 @multitable @columnfractions .4 .6
3606 @item @file{scm/auto-beam.scm}
3607 @tab Sub-beaming defaults
3608 @item @file{scm/define-grobs.scm}
3609 @tab Default settings for grob properties
3610 @item @file{scm/define-markup-commands.scm}
3611 @tab Specify all markup commands
3612 @item @file{scm/midi.scm}
3613 @tab Default settings for MIDI output
3614 @item @file{scm/output-lib.scm}
3615 @tab Settings that affect appearance of frets, colors,
3616 accidentals, bar lines, etc
3617 @item @file{scm/parser-clef.scm}
3618 @tab Definitions of supported clefs
3619 @item @file{scm/script.scm}
3620 @tab Default settings for articulations
3625 @node Avoiding tweaks with slower processing
3626 @subsection Avoiding tweaks with slower processing
3628 LilyPond can perform extra checks while it processes input files. These
3629 checks will take extra time to perform, but fewer manual tweaks
3630 may be required to obtain an acceptable result. If a text script
3631 or part of the lyrics extends over the margins these checks will
3632 compress that line of the score just enough to fit within the
3635 To be effective under all circumstances these checks must be enabled
3636 by placing the overrides in a Score @code{\with} block, rather than
3637 in-line in music, as follows:
3641 % Makes sure text scripts and lyrics are within the paper margins
3642 \override PaperColumn #'keep-inside-line = ##t
3643 \override NonMusicalPaperColumn #'keep-inside-line = ##t
3649 @node Advanced tweaks with Scheme
3650 @subsection Advanced tweaks with Scheme
3652 Although many things are possible with the @code{\override} and
3653 @code{\tweak} commands, an even more powerful way of modifying
3654 the action of LilyPond is available through a programmable
3655 interface to the LilyPond internal operation. Code written in
3656 the Scheme programming language can be incorporated directly in
3657 the internal operation of LilyPond. Of course, at least a basic
3658 knowledge of programming in Scheme is required to do this, and an
3659 introduction is provided in the @ref{Scheme tutorial}.
3661 As an illustration of one of the many possibilities, instead of
3662 setting a property to a constant it can be set to a Scheme
3663 procedure which is then called whenever that property is accessed
3664 by LilyPond. The property can then be set dynamically to a value
3665 determined by the procedure at the time it is called. In this
3666 example we color the note head in accordance with its position on
3669 @cindex x11-color function, example of using
3670 @cindex NoteHead, example of overriding
3671 @cindex color property, setting to Scheme procedure
3673 @lilypond[quote,verbatim,ragged-right]
3674 #(define (color-notehead grob)
3675 "Color the notehead according to its position on the staff."
3676 (let ((mod-position (modulo (ly:grob-property grob 'staff-position) 7)))
3678 ;; Return rainbow colors
3679 ((1) (x11-color 'red )) ; for C
3680 ((2) (x11-color 'orange )) ; for D
3681 ((3) (x11-color 'yellow )) ; for E
3682 ((4) (x11-color 'green )) ; for F
3683 ((5) (x11-color 'blue )) ; for G
3684 ((6) (x11-color 'purple )) ; for A
3685 ((0) (x11-color 'violet )) ; for B
3691 % Arrange to obtain color from color-notehead procedure
3692 \override NoteHead #'color = #color-notehead
3699 Some -- where o -- ver the Rain -- bow, way up high,
3703 Further examples showing the use of these programmable interfaces
3704 can be found in @ref{Tweaking with Scheme}.