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14 @chapter Tweaking output
16 This chapter discusses how to modify output. LilyPond is extremely
17 configurable; virtually every fragment of output may be changed.
22 * The Internals Reference manual::
23 * Appearance of objects::
24 * Placement of objects::
25 * Collisions of objects::
30 @section Tweaking basics
33 * Introduction to tweaks::
34 * Objects and interfaces::
35 * Naming conventions of objects and properties::
39 @node Introduction to tweaks
40 @subsection Introduction to tweaks
42 @q{Tweaking} is a LilyPond term for the various methods available
43 to the user for modifying the actions taken during interpretation
44 of the input file and modifying the appearance of the printed
45 output. Some tweaks are very easy to use; others are more
46 complex. But taken together the methods available for tweaking
47 permit almost any desired appearance of the printed music to be
50 In this section we cover the basic concepts required to understand
51 tweaking. Later we give a variety of ready-made commands which can
52 simply be copied to obtain the same effect in your own scores, and
53 at the same time we show how these commands may be constructed so
54 that you may learn how to develop your own tweaks.
56 Before starting on this Chapter you may wish to review the section
57 @ref{Contexts and engravers}, as Contexts, Engravers, and the
58 Properties contained within them are fundamental to understanding
59 and constructing Tweaks.
61 @node Objects and interfaces
62 @subsection Objects and interfaces
68 @cindex properties, object
69 @cindex object properties
71 @cindex object, layout
74 Tweaking involves modifying the internal operation and structures
75 of the LilyPond program, so we must first introduce some terms
76 which are used to describe those internal operations and
79 The term @q{Object} is a generic term used to refer to the
80 multitude of internal structures built by LilyPond during the
81 processing of an input file. So when a command like @code{\new
82 Staff} is encountered a new object of type @code{Staff} is
83 constructed. That @code{Staff} object then holds all the
84 properties associated with that particular staff, for example, its
85 name and its key signature, together with details of the engravers
86 which have been assigned to operate within that staff's context.
87 Similarly, there are objects to hold the properties of all other
88 contexts, such as @code{Voice} objects, @code{Score} objects,
89 @code{Lyrics} objects, as well as objects to represent all
90 notational elements such as bar lines,
91 note heads, ties, dynamics, etc. Every object has its own set of
94 Some types of object are given special names. Objects which represent
95 items of notation on the printed output such as note heads, stems,
96 slurs, ties, fingering, clefs, etc are called @q{Layout objects},
97 often known as @q{Graphical Objects}, or @q{Grobs} for short. These
98 are still objects in the generic sense above, and so they too all have
99 properties associated with them, such as their position, size, color,
102 Some layout objects are still more specialized. Phrasing slurs,
103 crescendo hairpins, ottava marks, and many other grobs are not
104 localized in a single place -- they have a starting point, an
105 ending point, and maybe other properties concerned with their
106 shape. Objects with an extended shape like these are called
109 It remains to explain what @q{Interfaces} are. Many objects, even
110 though they are quite different, share common features which need to
111 be processed in the same way. For example, all grobs have a color, a
112 size, a position, etc, and all these properties are processed in the
113 same way during LilyPond's interpretation of the input file. To
114 simplify these internal operations these common actions and properties
115 are grouped together in an object called a @code{grob-interface}.
116 There are many other groupings of common properties like this, each
117 one given a name ending in @code{interface}. In total there are over
118 100 such interfaces. We shall see later why this is of interest and
121 These, then, are the main terms relating to objects which we
122 shall use in this chapter.
124 @node Naming conventions of objects and properties
125 @subsection Naming conventions of objects and properties
127 @cindex naming conventions for objects
128 @cindex naming conventions for properties
129 @cindex objects, naming conventions
130 @cindex properties, naming conventions
132 We met some object naming conventions previously, in
133 @ref{Contexts and engravers}. Here for reference is a list
134 of the most common object and property types together with
135 the conventions for naming them and a couple of examples of
136 some real names. We have used @q{A} to stand for any capitalized
137 alphabetic character and @q{aaa} to stand for any number of
138 lower-case alphabetic characters. Other characters are used
141 @multitable @columnfractions .33 .33 .33
142 @headitem Object/property type
143 @tab Naming convention
146 @tab Aaaa or AaaaAaaaAaaa
147 @tab Staff, GrandStaff
149 @tab Aaaa or AaaaAaaaAaaa
152 @tab Aaaa_aaa_engraver
153 @tab Clef_engraver, Note_heads_engraver
155 @tab aaa-aaa-interface
156 @tab grob-interface, break-aligned-interface
157 @item Context Properties
158 @tab aaa or aaaAaaaAaaa
159 @tab alignAboveContext, skipBars
160 @item Layout Object Properties
161 @tab aaa or aaa-aaa-aaa
162 @tab direction, beam-thickness
165 As we shall see shortly, the properties of different types of
166 object are modified by different commands, so it is useful to
167 be able to recognize the type of object from the names of its
171 @node Tweaking methods
172 @subsection Tweaking methods
174 @cindex tweaking methods
176 @strong{\override command}
178 @cindex override command
179 @cindex override syntax
184 We have already met the commands @code{\set} and @code{\with}, used to
185 change the properties of @strong{contexts} and to remove and add
186 @strong{engravers}, in @ref{Modifying context properties}, and
187 @ref{Adding and removing engravers}. We must now introduce some more
190 The command to change the properties of @strong{layout objects} is
191 @code{\override}. Because this command has to modify
192 internal properties deep within LilyPond its syntax is not
193 as simple as the commands you have used so far. It needs to
194 know precisely which property of which object in which context
195 has to be modified, and what its new value is to be. Let's see
198 The general syntax of this command is:
201 \override @var{Context}.@var{LayoutObject} #'@var{layout-property} =
206 This will set the property with the name @var{layout-property} of the
207 layout object with the name @var{LayoutObject}, which is a member of
208 the @var{Context} context, to the value @var{value}.
210 The @var{Context} can be omitted (and usually is) when the
211 required context is unambiguously implied and is one of lowest
212 level contexts, i.e., @code{Voice}, @code{ChordNames} or
213 @code{Lyrics}, and we shall omit it in many of the following
214 examples. We shall see later when it must be specified.
216 Later sections deal comprehensively with properties and their
217 values, but to illustrate the format and use of these commands
218 we shall use just a few simple properties and values which are
221 For now, don't worry about the @code{#'}, which must precede the
222 layout property, and the @code{#}, which must precede the value.
223 These must always be present in exactly this form. This is the
224 most common command used in tweaking, and most of the rest of
225 this chapter will be directed to presenting examples of how it is
226 used. Here is a simple example to change the color of the
229 @cindex color property, example
230 @cindex NoteHead, example of overriding
232 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
234 \override NoteHead #'color = #red
236 \override NoteHead #'color = #green
240 @strong{\revert command}
242 @cindex revert command
247 Once overridden, the property retains its new value until it is
248 overridden again or a @code{\revert} command is encountered.
249 The @code{\revert} command has the following syntax and causes
250 the value of the property to revert to its original default
251 value; note, not its previous value if several @code{\override}
252 commands have been issued.
255 \revert @var{Context}.@var{LayoutObject} #'@var{layout-property}
258 Again, just like @var{Context} in the @code{\override} command,
259 @var{Context} is often not needed. It will be omitted
260 in many of the following examples. Here we revert the color
261 of the note head to the default value for the final two notes:
263 @cindex color property, example
264 @cindex NoteHead, example of overriding
266 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
268 \override NoteHead #'color = #red
270 \override NoteHead #'color = #green
272 \revert NoteHead #'color
276 @strong{\once prefix}
281 Both the @code{\override} and the @code{\set} commands may be
282 prefixed by @code{\once}. This causes the following
283 @code{\override} or @code{\set} command to be effective only
284 during the current musical moment before the property reverts
285 back to its default value. Using the same example, we can
286 change the color of a single note like this:
288 @cindex color property, example
289 @cindex NoteHead, example of overriding
291 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
293 \once \override NoteHead #'color = #red
295 \once \override NoteHead #'color = #green
299 @strong{\overrideProperty command}
301 @cindex overrideProperty command
303 @funindex \overrideProperty
304 @funindex overrideProperty
306 There is another form of the override command,
307 @code{\overrideProperty}, which is occasionally required.
308 We mention it here for completeness, but for details see
309 @rextend{Difficult tweaks}.
310 @c Maybe explain in a later iteration -td
312 @strong{\tweak command}
314 @cindex tweak command
319 The final tweaking command which is available is @code{\tweak}.
320 This should be used to change the properties of objects which
321 occur at the same musical moment, such as the notes within a
322 chord. Using @code{\override} would affect all the notes
323 within a chord, whereas @code{\tweak} affects just the following
324 item in the input stream.
326 Here's an example. Suppose we wish to change the size of the
327 middle note head (the E) in a C major chord. Let's first see what
328 @code{\once \override} would do:
330 @cindex font-size property, example
331 @cindex NoteHead, example of overriding
333 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
335 \once \override NoteHead #'font-size = #-3
340 We see the override affects @emph{all} the note heads in the chord.
341 This is because all the notes of a chord occur at the same
342 @emph{musical moment}, and the action of @code{\once} is to
343 apply the override to all layout objects of the type specified
344 which occur at the same musical moment as the @code{\override}
347 The @code{\tweak} command operates in a different way. It acts
348 on the immediately following item in the input stream. However,
349 it is effective only on objects which are created directly from
350 the input stream, essentially note heads and articulations;
351 objects such as stems and accidentals are created later and
352 cannot be tweaked in this way. Furthermore, when it is applied
353 to note heads these @emph{must} be within a chord, i.e., within
354 single angle brackets, so to tweak a single note the @code{\tweak}
355 command must be placed inside single angle brackets with the
358 So to return to our example, the size of the middle note of
359 a chord would be changed in this way:
361 @cindex font-size property, example
362 @cindex @code{\tweak}, example
364 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
366 <c \tweak #'font-size #-3 e g>4
369 Note that the syntax of @code{\tweak} is different from that
370 of the @code{\override} command. Neither the context nor the
371 layout object should be specified; in fact, it would generate
372 an error to do so. These are both implied by the following
373 item in the input stream. Note also that an equals sign should
374 not be present. So the general syntax of the
375 @code{\tweak} command is simply
378 \tweak #'@var{layout-property} #@var{value}
381 A @code{\tweak} command can also be used to modify just one in
382 a series of articulations, as shown here:
384 @cindex color property, example
385 @cindex @code{\tweak}, example
387 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
389 -\tweak #'color #red ^Red
390 -\tweak #'color #green _Green
394 Note that the @code{\tweak} command must be preceded by an
395 articulation mark as if it were an articulation itself.
397 @cindex tuplets, nested
398 @cindex triplets, nested
399 @cindex bracket, tuplet
400 @cindex bracket, triplet
401 @cindex tuplet bracket
402 @cindex triplet bracket
404 @funindex TupletBracket
406 The @code{\tweak} command must also be used to change the
407 appearance of one of a set of nested tuplets which begin at the
408 same musical moment. In the following example, the long tuplet
409 bracket and the first of the three short brackets begin at the
410 same musical moment, so any @code{\override} command would apply
411 to both of them. In the example, @code{\tweak} is used to
412 distinguish between them. The first @code{\tweak} command
413 specifies that the long tuplet bracket is to be placed above the
414 notes and the second one specifies that the tuplet number is to be
415 printed in red on the first short tuplet bracket.
417 @cindex @code{\tweak}, example
418 @cindex direction property, example
419 @cindex color property, example
421 @lilypond[quote,ragged-right,verbatim,fragment,relative=2]
422 \tweak #'direction #up
425 \times 2/3 { c8[ c8 c8] }
426 \times 2/3 { c8[ c8 c8] }
427 \times 2/3 { c8[ c8 c8] }
431 If nested tuplets do not begin at the same moment, their
432 appearance may be modified in the usual way with
433 @code{\override} commands:
435 @cindex text property, example
436 @cindex tuplet-number function, example
437 @cindex transparent property, example
438 @cindex TupletNumber, example of overriding
440 @c NOTE Tuplet brackets collide if notes are high on staff
442 @lilypond[quote,ragged-right,verbatim,fragment,relative=1]
443 \times 2/3 { c8[ c c]}
444 \once \override TupletNumber
445 #'text = #tuplet-number::calc-fraction-text
449 \once \override TupletNumber #'transparent = ##t
450 \times 2/3 { c8[ c c] }
451 \times 2/3 { c8[ c c]}
458 @ruser{The tweak command}.
461 @node The Internals Reference manual
462 @section The Internals Reference manual
464 @cindex Internals Reference
467 * Properties of layout objects::
468 * Properties found in interfaces::
469 * Types of properties::
472 @node Properties of layout objects
473 @subsection Properties of layout objects
475 @cindex properties of layout objects
476 @cindex properties of grobs
477 @cindex grobs, properties of
478 @cindex layout objects, properties of
479 @cindex Internals Reference manual
481 Suppose you have a slur in a score which, to your mind,
482 appears too thin and you'd like to draw it a little heavier.
483 How do you go about doing this? You know from the statements
484 earlier about the flexibility of LilyPond that such a thing
485 should be possible, and you would probably guess that an
486 @code{\override} command would be needed. But is there a
487 heaviness property for a slur, and if there is, how might it
488 be modified? This is where the Internals Reference manual
489 comes in. It contains all the information you might need to
490 construct this and all other @code{\override} commands.
492 Before we look at the Internals Reference a word of warning.
493 This is a @strong{reference} document, which means there is
494 little or no explanation contained within it: its purpose is
495 to present information precisely and concisely. This
496 means it might look daunting at first sight. Don't worry!
497 The guidance and explanation presented here will enable you
498 to extract the information from the Internals Reference for
499 yourself with just a little practice.
501 @cindex override example
502 @cindex Internals Reference, example of using
503 @cindex @code{\addlyrics} example
505 Let's use a concrete example with a simple fragment of real
508 @lilypond[quote,verbatim,relative=2]
513 g[( e]) e d[( f]) a |
517 The man who feels love's sweet e -- mo -- tion
522 Suppose now that we decide we would like the slurs to be a
523 little heavier. Is this possible? The slur is certainly a
524 layout object, so the question is, @q{Is there a property
525 belonging to a slur which controls the heaviness?} To answer
526 this we must look in the Internals Reference, or IR for short.
528 The IR for the version of LilyPond you are using may be found
529 on the LilyPond website at @uref{http://lilypond.org}. Go to the
530 documentation page and click on the Internals Reference link.
531 For learning purposes you should use the standard HTML version,
532 not the @q{one big page} or the PDF. For the next few
533 paragraphs to make sense you will need to actually do this
536 Under the heading @strong{Top} you will see five links. Select
537 the link to the @emph{Backend}, which is where information about
538 layout objects is to be found. There, under the heading
539 @strong{Backend}, select the link to @emph{All layout objects}.
540 The page that appears lists all the layout objects used in your
541 version of LilyPond, in alphabetic order. Select the link to
542 Slur, and the properties of Slurs are listed.
544 An alternative way of finding this page is from the Notation
545 Reference. On one of the pages that deals with slurs you may find a
546 link to the Internals Reference. This link will take you directly to
547 this page, but if you have an idea about the name of the layout object
548 to be tweaked, it is easier to go straight to the IR and search there.
550 This Slur page in the IR tells us first that Slur objects are created
551 by the Slur_engraver. Then it lists the standard settings. Note
552 these are @strong{not} in alphabetic order. Browse down them looking
553 for a property that might control the heaviness of slurs, and you
557 @code{thickness} (number)
559 Line thickness, generally measured in @code{line-thickness}
562 This looks a good bet to change the heaviness. It tells us that
563 the value of @code{thickness} is a simple @emph{number},
564 that the default value is 1.2, and that the units are
565 in another property called @code{line-thickness}.
567 As we said earlier, there are few to no explanations in the IR,
568 but we already have enough information to try changing the
569 slur thickness. We see that the name of the layout object
570 is @code{Slur}, that the name of the property to change is
571 @code{thickness} and that the new value should be a number
572 somewhat larger than 1.2 if we are to make slurs thicker.
574 We can now construct the @code{\override} command by simply
575 substituting the values we have found for the names, omitting
576 the context. Let's use a very large value for the thickness
577 at first, so we can be sure the command is working. We get:
580 \override Slur #'thickness = #5.0
583 Don't forget the @code{#'} preceding the
584 property name and a @code{#} preceding the new value!
586 The final question is, @q{Where should this command be
587 placed?} While you are unsure and learning, the best
588 answer is, @q{Within the music, before the first slur and
589 close to it.} Let's do that:
591 @cindex Slur example of overriding
592 @cindex thickness property, example
594 @lilypond[quote,verbatim,relative=2]
598 % Increase thickness of all following slurs from 1.2 to 5.0
599 \override Slur #'thickness = #5.0
601 g[( e]) e d[( f]) a |
605 The man who feels love's sweet e -- mo -- tion
611 and we see that the slur is indeed heavier.
613 So this is the basic way of constructing @code{\override}
614 commands. There are a few more complications that we
615 shall meet in later sections, but you now know all the
616 essentials required to make up your own -- but you will
617 still need some practice. This is provided in the examples
620 @subheading Finding the context
622 @cindex context, finding
623 @cindex context, identifying correct
625 But first, what if we had needed to specify the Context?
626 What should it be? We could guess that slurs are in
627 the Voice context, as they are clearly closely associated
628 with individual lines of music, but can we be sure? To
629 find out, go back to the top of the IR page describing the
630 Slur, where it says @q{Slur objects are created by: Slur
631 engraver}. So slurs will be created in whichever context
632 the @code{Slur_engraver} is in. Follow the link to the
633 @code{Slur_engraver} page. At the very bottom it tells
634 us that @code{Slur_engraver} is part of five Voice contexts,
635 including the standard voice context, @code{Voice}, so our
636 guess was correct. And because @code{Voice} is one of the
637 lowest level contexts which is implied unambiguously by
638 the fact that we are entering notes, we can omit it in this
641 @subheading Overriding once only
643 @cindex overriding once only
644 @cindex once override
649 As you can see, @emph{all} the slurs are thicker in the final example
650 above. But what if we wanted just the first slur to be thicker? This
651 is achieved with the @code{\once} command. Placed immediately before
652 the @code{\override} command it causes it to change only the slur
653 which begins on the @strong{immediately following} note. If the
654 immediately following note does not begin a slur the command has no
655 effect at all -- it is not remembered until a slur is encountered, it
656 is simply discarded. So the command with @code{\once} must be
657 repositioned as follows:
659 @cindex Slur, example of overriding
660 @cindex thickness property, example
662 @lilypond[quote,verbatim,relative=2]
667 % Increase thickness of immediately following slur only
668 \once \override Slur #'thickness = #5.0
670 g[( e]) e d[( f]) a |
674 The man who feels love's sweet e -- mo -- tion
680 Now only the first slur is made heavier.
682 The @code{\once} command can also be used before the @code{\set}
685 @subheading Reverting
688 @cindex default properties, reverting to
693 Finally, what if we wanted just the first two slurs to be
694 heavier? Well, we could use two commands, each preceded by
695 @code{\once} placed immediately before each of the notes where
698 @cindex Slur, example of overriding
699 @cindex thickness property, example
701 @lilypond[quote,verbatim,relative=2]
706 % Increase thickness of immediately following slur only
707 \once \override Slur #'thickness = #5.0
709 % Increase thickness of immediately following slur only
710 \once \override Slur #'thickness = #5.0
711 g[( e]) e d[( f]) a |
715 The man who feels love's sweet e -- mo -- tion
721 or we could omit the @code{\once} command and use the @code{\revert}
722 command to return the @code{thickness} property to its default value
723 after the second slur:
725 @cindex Slur, example of overriding
726 @cindex thickness property, example
728 @lilypond[quote,verbatim,relative=2]
733 % Increase thickness of all following slurs from 1.2 to 5.0
734 \override Slur #'thickness = #5.0
737 % Revert thickness of all following slurs to default of 1.2
738 \revert Slur #'thickness
743 The man who feels love's sweet e -- mo -- tion
749 The @code{\revert} command can be used to return any property
750 changed with @code{\override} back to its default value.
751 You may use whichever method best suits what you want to do.
753 That concludes our introduction to the IR, and the basic
754 method of tweaking. Several examples follow in the later
755 sections of this Chapter, partly to introduce you to some of the
756 additional features of the IR, and partly to give you more
757 practice in extracting information from it. These examples will
758 contain progressively fewer words of guidance and explanation.
761 @node Properties found in interfaces
762 @subsection Properties found in interfaces
765 @cindex interface properties
766 @cindex properties in interfaces
768 Suppose now that we wish to print the lyrics in italics. What form of
769 @code{\override} command do we need to do this? We first look in the
770 IR page listing @q{All layout objects}, as before, and look for an
771 object that might control lyrics. We find @code{LyricText}, which
772 looks right. Clicking on this shows the settable properties for lyric
773 text. These include the @code{font-series} and @code{font-size}, but
774 nothing that might give an italic shape. This is because the shape
775 property is one that is common to all font objects, so, rather than
776 including it in every layout object, it is grouped together with other
777 similar common properties and placed in an @strong{Interface}, the
778 @code{font-interface}.
780 So now we need to learn how to find the properties of interfaces,
781 and to discover what objects use these interface properties.
783 Look again at the IR page which describes LyricText. At the bottom of
784 the page is a list of clickable interfaces which LyricText supports.
785 The list has several items, including @code{font-interface}. Clicking
786 on this brings up the properties associated with this interface, which
787 are also properties of all the objects which support it, including
790 Now we see all the user-settable properties which control fonts,
791 including @code{font-shape(symbol)}, where @code{symbol} can be
792 set to @code{upright}, @code{italics} or @code{caps}.
794 You will notice that @code{font-series} and @code{font-size} are also
795 listed there. This immediately raises the question: Why are the
796 common font properties @code{font-series} and @code{font-size} listed
797 under @code{LyricText} as well as under the interface
798 @code{font-interface} but @code{font-shape} is not? The answer is
799 that @code{font-series} and @code{font-size} are changed from their
800 global default values when a @code{LyricText} object is created, but
801 @code{font-shape} is not. The entries in @code{LyricText} then tell
802 you the values for those two properties which apply to
803 @code{LyricText}. Other objects which support @code{font-interface}
804 will set these properties differently when they are created.
806 Let's see if we can now construct the @code{\override} command
807 to change the lyrics to italics. The object is @code{LyricText},
808 the property is @code{font-shape} and the value is
809 @code{italic}. As before, we'll omit the context.
811 As an aside, although it is an important one, note that because the
812 values of @code{font-shape} are symbols they must be introduced with a
813 single apostrophe, @code{'}. That is why apostrophes are needed
814 before @code{thickness} in the earlier example and @code{font-shape}.
815 These are both symbols too. Symbols are then read internally by
816 LilyPond. Some of them are the names of properties, like
817 @code{thickness} or @code{font-shape}, others are used as values that
818 can be given to properties, like @code{italic}. Note the distinction
819 from arbitrary text strings, which would appear as @code{"a text
820 string"}; for more details about symbols and strings, see
821 @rextend{Scheme tutorial}.
823 So we see that the @code{\override} command needed to print the lyrics
827 \override LyricText #'font-shape = #'italic
831 This should be placed just in front of the lyrics we wish to affect,
834 @cindex font-shape property, example
835 @cindex italic, example
836 @cindex LyricText, example of overriding
837 @cindex @code{\addlyrics}, example
839 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
844 g[( e]) e d[( f]) a |
848 \override LyricText #'font-shape = #'italic
849 The man who feels love's sweet e -- mo -- tion
855 and the lyrics are all printed in italics.
857 @subheading Specifying the context in lyric mode
859 @cindex context, specifying in lyric mode
860 @cindex lyric mode, specifying context
862 In the case of lyrics, if you try specifying the context in the
863 format given earlier the command will fail. A syllable
864 entered in lyricmode is terminated by either a space,
865 a newline or a digit. All other characters are included
866 as part of the syllable. For this reason a space or newline
867 must appear before the terminating @code{@}} to prevent it being
868 included as part of the final syllable. Similarly,
869 spaces must be inserted before and after the
870 period or dot, @q{.}, separating the context name from the
871 object name, as otherwise the two names are run together and
872 the interpreter cannot recognize them. So the command should be:
875 \override Lyrics . LyricText #'font-shape = #'italic
878 @warning{In lyrics always leave whitespace between the final
879 syllable and the terminating brace.}
881 @warning{In overrides in lyrics always place spaces around
882 the dot between the context name and the object name.}
886 Extending: @rextend{Scheme tutorial}.
889 @node Types of properties
890 @subsection Types of properties
892 @cindex property types
894 So far we have seen two types of property: @code{number} and
895 @code{symbol}. To be valid, the value given to a property
896 must be of the correct type and obey the rules for that type.
897 The type of property is always shown in brackets after the
898 property name in the IR. Here is a list of the types you may
899 need, together with the rules for that type, and some examples.
900 You must always add a hash symbol, @code{#}, of course,
901 to the front of these values when they are entered in the
902 @code{\override} command.
904 @multitable @columnfractions .2 .45 .35
905 @headitem Property type
909 @tab Either True or False, represented by #t or #f
910 @tab @code{#t}, @code{#f}
911 @item Dimension (in staff space)
912 @tab A positive decimal number (in units of staff space)
913 @tab @code{2.5}, @code{0.34}
915 @tab A valid direction constant or its numerical equivalent (decimal
916 values between -1 and 1 are allowed)
917 @tab @code{LEFT}, @code{CENTER}, @code{UP},
920 @tab A positive whole number
921 @tab @code{3}, @code{1}
923 @tab A set of values separated by spaces, enclosed in parentheses
924 and preceded by an apostrophe
925 @tab @code{'(left-edge staff-bar)}, @code{'(1)},
926 @code{'(1.0 0.25 0.5)}
928 @tab Any valid markup
929 @tab @code{\markup @{ \italic "cresc." @}}
931 @tab A fraction of a whole note constructed with the
933 @tab @code{(ly:make-moment 1 4)},
934 @code{(ly:make-moment 3 8)}
936 @tab Any positive or negative decimal value
937 @tab @code{3.5}, @code{-2.45}
938 @item Pair (of numbers)
939 @tab Two numbers separated by a @q{space . space} and enclosed
940 in brackets preceded by an apostrophe
941 @tab @code{'(2 . 3.5)}, @code{'(0.1 . -3.2)}
943 @tab Any of the set of permitted symbols for that property,
944 preceded by an apostrophe
945 @tab @code{'italic}, @code{'inside}
947 @tab A procedure, or @code{#f} to cause no action
948 @tab @code{bend::print}, @code{ly:text-interface::print},
951 @tab A list of three items enclosed in parentheses and preceded
952 by apostrophe-hash, @code{'#}.
953 @tab @code{'#(#t #t #f)}
958 Extending: @rextend{Scheme tutorial}.
961 @node Appearance of objects
962 @section Appearance of objects
964 Let us now put what we have learned into practice with a few
965 examples which show how tweaks may be used to change the
966 appearance of the printed music.
969 * Visibility and color of objects::
971 * Length and thickness of objects::
974 @node Visibility and color of objects
975 @subsection Visibility and color of objects
977 In the educational use of music we might wish to print a score
978 with certain elements omitted as an exercise for the student,
979 who is required to supply them. As a simple example,
980 let us suppose the exercise is to supply the missing bar lines
981 in a piece of music. But the bar lines are normally inserted
982 automatically. How do we prevent them printing?
984 Before we tackle this, let us remember that object properties are
985 grouped in what are called @emph{interfaces} -- see @ref{Properties
986 found in interfaces}. This is simply to group together those
987 properties that may be used together to tweak a graphical object -- if
988 one of them is allowed for an object, so are the others. Some objects
989 then use the properties in some interfaces, others use them from other
990 interfaces. The interfaces which contain the properties used by a
991 particular grob are listed in the IR at the bottom of the page
992 describing that grob, and those properties may be viewed by looking at
995 We explained how to find information about grobs in @ref{Properties of
996 layout objects}. Using the same approach, we go to the IR to find the
997 layout object which prints bar lines. Going via @emph{Backend} and
998 @emph{All layout objects} we find there is a layout object called
999 @code{BarLine}. Its properties include two that control its
1000 visibility: @code{break-visibility} and @code{stencil}. Barline also
1001 supports a number of interfaces, including the @code{grob-interface},
1002 where we find the @code{transparent} and the @code{color} properties.
1003 All of these can affect the visibility of bar lines (and, of course,
1004 by extension, many other layout objects too.) Let's consider each of
1009 @cindex stencil property
1011 This property controls the appearance of the bar lines by specifying
1012 the symbol (glyph) which should be printed. In common
1013 with many other properties, it can be set to print nothing by
1014 setting its value to @code{#f}. Let's try it, as before, omitting
1015 the implied Context, @code{Voice}:
1017 @cindex BarLine, example of overriding
1018 @cindex stencil property, example
1020 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1023 \override BarLine #'stencil = ##f
1025 g, a16 b8 c d4 e16 |
1030 The bar lines are still printed. What is wrong? Go back to the IR
1031 and look again at the page giving the properties of BarLine. At the
1032 top of the page it says @qq{Barline objects are created by:
1033 Bar_engraver}. Go to the @code{Bar_engraver} page. At the bottom it
1034 gives a list of Contexts in which the bar engraver operates. All of
1035 them are of the type @code{Staff}, so the reason the @code{\override}
1036 command failed to work as expected is because @code{Barline} is not in
1037 the default @code{Voice} context. If the context is specified
1038 incorrectly, the command simply does not work. No error message is
1039 produced, and nothing is logged in the log file. Let's try correcting
1040 it by adding the correct context:
1042 @cindex BarLine, example of overriding
1043 @cindex stencil property, example
1045 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1048 \override Staff.BarLine #'stencil = ##f
1050 g, a16 b8 c d4 e16 |
1055 Now the bar lines have vanished.
1057 Note, though, that setting the @code{stencil} property to @code{#f}
1058 will cause errors when the dimensions of the object are required for
1059 correct processing. For example, errors will be generated if the
1060 @code{stencil} property of the @code{NoteHead} object is set to
1061 @code{#f}. If this is the case, you can instead use the
1062 @code{point-stencil} function, which sets the stencil to a object
1065 @lilypond[quote,verbatim,relative=2]
1068 \once \override NoteHead #'stencil = #point-stencil
1073 @subheading break-visibility
1075 @cindex break-visibility property
1077 We see from the @code{BarLine} properties in the IR that the
1078 @code{break-visibility} property requires a vector of three booleans.
1079 These control respectively whether bar lines are printed at the end of
1080 a line, in the middle of lines, and at the beginning of lines. For
1081 our example we want all bar lines to be suppressed, so the value we
1082 need is @code{'#(#f #f #f)}. Let's try that, remembering to include
1083 the @code{Staff} context. Note also that in writing this value we
1084 have @code{#'#} before the opening bracket. The @code{'#} is required
1085 as part of the value to introduce a vector, and the first @code{#} is
1086 required, as always, to precede the value itself in the
1087 @code{\override} command.
1089 @cindex BarLine, example of overriding
1090 @cindex break-visibility property, example
1092 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1095 \override Staff.BarLine #'break-visibility = #'#(#f #f #f)
1097 g, a16 b8 c d4 e16 |
1102 And we see this too removes all the bar lines.
1104 @subheading transparent
1106 @cindex transparent property
1107 @cindex transparency
1109 We see from the properties specified in the @code{grob-interface} page
1110 in the IR that the @code{transparent} property is a boolean. This
1111 should be set to @code{#t} to make the grob transparent. In this next
1112 example let us make the time signature invisible rather than the bar
1113 lines. To do this we need to find the grob name for the time
1114 signature. Back to the @q{All layout objects} page in the IR to find
1115 the properties of the @code{TimeSignature} layout object. This is
1116 produced by the @code{Time_signature_engraver} which you can check
1117 also lives in the @code{Staff} context and also supports the
1118 @code{grob-interface}. So the command to make the time signature
1121 @cindex TimeSignature, example of overriding
1122 @cindex transparent property, example
1124 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1127 \override Staff.TimeSignature #'transparent = ##t
1129 g, a16 b8 c d4 e16 |
1135 The time signature is gone, but this command leaves a gap where
1136 the time signature should be. Maybe this is what is wanted for
1137 an exercise for the student to fill it in, but in other
1138 circumstances a gap might be undesirable. To remove it, the
1139 stencil for the time signature should be set to @code{#f}
1142 @cindex TimeSignature, example of overriding
1143 @cindex stencil property, example
1145 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1148 \override Staff.TimeSignature #'stencil = ##f
1150 g, a16 b8 c d4 e16 |
1156 and the difference is obvious: setting the stencil to @code{#f}
1157 removes the object entirely; making the object @code{transparent}
1158 leaves it where it is, but makes it invisible.
1162 @cindex color property
1164 Finally let us try making the bar lines invisible by coloring
1165 them white. (There is a difficulty with this in that the
1166 white bar line may or may not blank out the staff lines where
1167 they cross. You may see in some of the examples below that this
1168 happens unpredictably. The details of why this is so and how to
1169 control it are covered in @ruser{Painting objects white}. But at
1170 the moment we are learning about color, so please just accept this
1171 limitation for now.)
1173 The @code{grob-interface} specifies that the
1174 color property value is a list, but there is no
1175 explanation of what that list should be. The list it
1176 requires is actually a list of values in internal units,
1177 but, to avoid having to know what these are, several ways
1178 are provided to specify colors. The first way is to use one
1179 of the @q{normal} colors listed in the first table in
1180 @ruser{List of colors}. To set the bar lines to white
1183 @cindex BarLine, example of overriding
1184 @cindex color property, example
1186 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1189 \override Staff.BarLine #'color = #white
1191 g, a16 b8 c d4 e16 |
1197 and again, we see the bar lines are not visible. Note that
1198 @emph{white} is not preceded by an apostrophe -- it is not
1199 a symbol, but a @emph{function}. When called, it provides
1200 the list of internal values required to set the color to
1201 white. The other colors in the normal list are functions
1202 too. To convince yourself this is working you might like
1203 to change the color to one of the other functions in the
1211 The second way of changing the color is to use the list of
1212 X11 color names in the second list in @ruser{List of colors}.
1213 However, these must be preceded by another function, which
1214 converts X11 color names into the list of internal values,
1215 @code{x11-color}, like this:
1217 @cindex BarLine, example of overriding
1218 @cindex color property, example
1220 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1223 \override Staff.BarLine #'color = #(x11-color 'white)
1225 g, a16 b8 c d4 e16 |
1231 Note that in this case the function @code{x11-color} takes
1232 a symbol as an argument, so the symbol must be preceded by
1233 an apostrophe and the two enclosed in brackets.
1240 There is yet a third function, one which converts RGB values into
1241 internal colors -- the @code{rgb-color} function. This takes
1242 three arguments giving the intensities of the red, green and
1243 blue colors. These take values in the range 0 to 1. So to
1244 set the color to red the value should be @code{(rgb-color 1 0 0)}
1245 and to white it should be @code{(rgb-color 1 1 1)}:
1247 @cindex BarLine, example of overriding
1248 @cindex color property, example
1250 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1253 \override Staff.BarLine #'color = #(rgb-color 1 1 1)
1255 g, a16 b8 c d4 e16 |
1260 Finally, there is also a grey scale available as part of the
1261 X11 set of colors. These range from black, @code{'grey0'},
1262 to white, @code{'grey100}, in steps of 1. Let's illustrate
1263 this by setting all the layout objects in our example to
1264 various shades of grey:
1266 @cindex StaffSymbol, example of overriding
1267 @cindex TimeSignature, example of overriding
1268 @cindex Clef, example of overriding
1269 @cindex NoteHead, example of overriding
1270 @cindex Stem, example of overriding
1271 @cindex BarLine, example of overriding
1272 @cindex color property, example
1273 @cindex x11-color, example of using
1275 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1278 \override Staff.StaffSymbol #'color = #(x11-color 'grey30)
1279 \override Staff.TimeSignature #'color = #(x11-color 'grey60)
1280 \override Staff.Clef #'color = #(x11-color 'grey60)
1281 \override Voice.NoteHead #'color = #(x11-color 'grey85)
1282 \override Voice.Stem #'color = #(x11-color 'grey85)
1283 \override Staff.BarLine #'color = #(x11-color 'grey10)
1285 g, a16 b8 c d4 e16 |
1291 Note the contexts associated with each of the layout objects.
1292 It is important to get these right, or the commands will not
1293 work! Remember, the context is the one in which the appropriate
1294 engraver is placed. The default context for engravers can be
1295 found by starting from the layout object, going from there to
1296 the engraver which produces it, and on the engraver page in the
1297 IR it tells you in which context the engraver will normally be
1301 @node Size of objects
1302 @subsection Size of objects
1304 @cindex changing size of objects
1305 @cindex size of objects
1306 @cindex objects, size of
1307 @cindex objects, changing size of
1309 Let us begin by looking again at the earlier example
1310 see @ref{Nesting music expressions}) which showed
1311 how to introduce a new temporary staff, as in an @rglos{ossia}.
1313 @cindex alignAboveContext property, example
1314 @cindex @code{\with}, example
1316 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1317 \new Staff ="main" {
1324 alignAboveContext = #"main" }
1332 Ossia are normally written without clef and time signature, and
1333 are usually printed slightly smaller than the main staff. We
1334 already know now how to remove the clef and time signature --
1335 we simply set the stencil of each to @code{#f}, as follows:
1337 @cindex alignAboveContext property, example
1338 @cindex @code{\with}, example
1339 @cindex stencil property, example
1340 @cindex Clef, example of overriding
1341 @cindex TimeSignature, example of overriding
1343 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1344 \new Staff ="main" {
1351 alignAboveContext = #"main"
1354 \override Staff.Clef #'stencil = ##f
1355 \override Staff.TimeSignature #'stencil = ##f
1365 where the extra pair of braces after the @code{\with} clause are
1366 required to ensure the enclosed overrides and music are applied
1369 But what is the difference between modifying the staff context by
1370 using @code{\with} and modifying the stencils of the clef and the
1371 time signature with \override? The main difference is that
1372 changes made in a @code{\with} clause are made at the time the
1373 context is created, and remain in force as the @strong{default}
1374 values for the duration of that context, whereas
1375 @code{\set} or @code{\override} commands embedded in the
1376 music are dynamic -- they make changes synchronized with
1377 a particular point in the music. If changes are unset or
1378 reverted using @code{\unset} or @code{\revert} they return to
1379 their default values, which will be the ones set in the
1380 @code{\with} clause, or if none have been set there, the normal
1383 Some context properties can be modified only in @code{\with} clauses.
1384 These are those properties which cannot sensibly be changed after the
1385 context has been created. @code{alignAboveContext} and its partner,
1386 @code{alignBelowContext}, are two such properties -- once the staff
1387 has been created its alignment is decided and it would make no sense
1388 to try to change it later.
1390 The default values of layout object properties can also be set
1391 in @code{\with} clauses. Simply use the normal @code{\override}
1392 command leaving out the context name, since this is unambiguously
1393 defined as the context which the @code{\with} clause is modifying.
1394 If fact, an error will be generated if a context is specified
1397 So we could replace the example above with
1399 @cindex alignAboveContext property, example
1400 @cindex @code{\with}, example
1401 @cindex Clef, example of overriding
1402 @cindex TimeSignature, example of overriding
1404 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1405 \new Staff ="main" {
1412 alignAboveContext = #"main"
1413 % Don't print clefs in this staff
1414 \override Clef #'stencil = ##f
1415 % Don't print time signatures in this staff
1416 \override TimeSignature #'stencil = ##f
1425 Finally we come to changing the size of layout objects.
1427 Some layout objects are created as glyphs selected from a typeface
1428 font. These include note heads, accidentals, markup, clefs, time
1429 signatures, dynamics and lyrics. Their size is changed by modifying
1430 the @code{font-size} property, as we shall shortly see. Other layout
1431 objects such as slurs and ties -- in general, spanner objects -- are
1432 drawn individually, so there is no @code{font-size} associated with
1433 them. These objects generally derive their size from the objects to
1434 which they are attached, so usually there is no need to change their
1435 size manually. Still other properties such as the length of stems and
1436 bar lines, thickness of beams and other lines, and the separation of
1437 staff lines all need to be modified in special ways.
1439 Returning to the ossia example, let us first change the font-size.
1440 We can do this in two ways. We can either change the size of the
1441 fonts of each object type, like @code{NoteHead}s with commands
1445 \override NoteHead #'font-size = #-2
1448 or we can change the size of all fonts by setting a special
1449 property, @code{fontSize}, using @code{\set}, or by including
1450 it in a @code{\with} clause (but without the @code{\set}).
1456 Both of these statements would cause the font size to be reduced
1457 by 2 steps from its previous value, where each
1458 step reduces or increases the size by approximately 12%.
1460 Let's try it in our ossia example:
1462 @cindex alignAboveContext property, example
1463 @cindex @code{\with}, example
1464 @cindex Clef, example of overriding
1465 @cindex TimeSignature, example of overriding
1466 @cindex fontSize property, example
1468 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1469 \new Staff ="main" {
1476 alignAboveContext = #"main"
1477 \override Clef #'stencil = ##f
1478 \override TimeSignature #'stencil = ##f
1479 % Reduce all font sizes by ~24%
1489 This is still not quite right. The note heads and flags are
1490 smaller, but the stems are too long in proportion and the
1491 staff lines are spaced too widely apart. These need to be
1492 scaled down in proportion to the font reduction. The next
1493 sub-section discusses how this is done.
1495 @node Length and thickness of objects
1496 @subsection Length and thickness of objects
1502 @cindex size, changing
1503 @cindex stem length, changing
1504 @cindex staff line spacing, changing
1506 Distances and lengths in LilyPond are generally measured in
1507 staff-spaces, the distance between adjacent lines in the staff,
1508 (or occasionally half staff spaces) while most @code{thickness}
1509 properties are measured in units of an internal property called
1510 @code{line-thickness.} For example, by default, the lines of
1511 hairpins are given a thickness of 1 unit of @code{line-thickness},
1512 while the @code{thickness} of a note stem is 1.3. Note, though,
1513 that some thickness properties are different; for example, the
1514 thickness of beams is controlled by the value of the
1515 @code{beam-thickness} property, which is measured in staff-spaces.
1517 So how are lengths to be scaled in proportion to the font size?
1518 This can be done with the help of a special function called
1519 @code{magstep} provided for exactly this purpose. It takes
1520 one argument, the change in font size (#-2 in the example above)
1521 and returns a scaling factor suitable for reducing other
1522 objects in proportion. It is used like this:
1524 @cindex alignAboveContext property, example
1525 @cindex @code{\with}, example
1526 @cindex Clef, example of overriding
1527 @cindex TimeSignature, example of overriding
1528 @cindex fontSize property, example
1529 @cindex StaffSymbol, example of overriding
1530 @cindex magstep function, example of using
1531 @cindex staff-space property, example
1532 @cindex stencil property, example
1534 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1535 \new Staff ="main" {
1542 alignAboveContext = #"main"
1543 \override Clef #'stencil = ##f
1544 \override TimeSignature #'stencil = ##f
1546 % Reduce stem length and line spacing to match
1547 \override StaffSymbol #'staff-space = #(magstep -2)
1557 Since the length of stems and many other length-related properties are
1558 always calculated relative to the value of the @code{staff-space}
1559 property these are automatically scaled down in length too. Note that
1560 this affects only the vertical scale of the ossia -- the horizontal
1561 scale is determined by the layout of the main music in order to remain
1562 synchronized with it, so it is not affected by any of these changes in
1563 size. Of course, if the scale of all the main music were changed in
1564 this way then the horizontal spacing would be affected. This is
1565 discussed later in the layout section.
1567 This, then, completes the creation of an ossia. The sizes and
1568 lengths of all other objects may be modified in analogous ways.
1570 For small changes in scale, as in the example above, the
1571 thickness of the various drawn lines such as bar lines,
1572 beams, hairpins, slurs, etc does not usually require global
1573 adjustment. If the thickness of any particular layout object
1574 needs to be adjusted this can be best achieved by overriding its
1575 @code{thickness} property. An example of changing the thickness
1576 of slurs was shown above in @ref{Properties of layout objects}.
1577 The thickness of all drawn objects (i.e., those not produced
1578 from a font) may be changed in the same way.
1581 @node Placement of objects
1582 @section Placement of objects
1585 * Automatic behavior::
1586 * Within-staff objects::
1587 * Outside-staff objects::
1591 @node Automatic behavior
1592 @subsection Automatic behavior
1594 @cindex within-staff objects
1595 @cindex outside-staff objects
1596 @cindex objects, within-staff
1597 @cindex objects, outside-staff
1599 There are some objects in musical notation that belong to
1600 the staff and there are other objects that should be
1601 placed outside the staff. These are called within-staff
1602 objects and outside-staff objects respectively.
1604 Within-staff objects are those that are located on the staff
1605 -- note heads, stems, accidentals, etc. The positions of
1606 these are usually fixed by the music itself -- they are
1607 vertically positioned on specific lines of the staff or are
1608 tied to other objects that are so positioned. Collisions of
1609 note heads, stems and accidentals in closely set chords are
1610 normally avoided automatically. There are commands and
1611 overrides which can modify this automatic behavior, as we
1614 Objects belonging outside the staff include things such as
1615 rehearsal marks, text and dynamic markings. LilyPond's rule for
1616 the vertical placement of outside-staff objects is to place them
1617 as close to the staff as possible but not so close that they
1618 collide with any other object. LilyPond uses the
1619 @code{outside-staff-priority} property to determine the order in
1620 which the objects should be placed, as follows.
1622 First, LilyPond places all the within-staff objects.
1623 Then it sorts the outside-staff objects according to their
1624 @code{outside-staff-priority}. The outside-staff objects are
1625 taken one by one, beginning with the object with the lowest
1626 @code{outside-staff-priority}, and placed so that they do not
1627 collide with any objects that have already been placed. That is,
1628 if two outside-staff grobs are competing for the same space, the
1629 one with the lower @code{outside-staff-priority} will be placed
1630 closer to the staff. If two objects have the same
1631 @code{outside-staff-priority} the one encountered first will be
1632 placed closer to the staff.
1634 In the following example all the markup texts have the same
1635 priority (since it is not explicitly set). Note that @q{Text3}
1636 is automatically positioned close to the staff again, nestling
1639 @cindex markup example
1641 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1648 Staves are also positioned, by default, as closely together as
1649 possible (subject to a minimum separation). If notes project
1650 a long way towards an adjacent staff they will force the
1651 staves further apart only if an overlap of the notation
1652 would otherwise occur. The following example demonstrates
1653 this @q{nestling} of the notes on adjacent staves:
1655 @lilypond[quote,ragged-right,verbatim]
1658 \relative c' { c a, }
1661 \relative c'''' { c a, }
1667 @node Within-staff objects
1668 @subsection Within-staff objects
1670 We have already seen how the commands @code{\voiceXXX} affect
1671 the direction of slurs, ties, fingering and
1672 everything else which depends on the direction of the stems.
1673 These commands are essential when writing polyphonic music to
1674 permit interweaving melodic lines to be distinguished.
1675 But occasionally it may be necessary to override this automatic
1676 behavior. This can be done for whole sections of music or even
1677 for an individual note. The property which controls this
1678 behavior is the @code{direction} property of each layout object.
1679 We first explain what this does, and then introduce a number of
1680 ready-made commands which avoid your having to code explicit
1681 overrides for the more common modifications.
1683 Some layout objects like slurs and ties curve, bend or point
1684 either up or down; others like stems and flags also move to
1685 right or left when they point up or down. This is controlled
1686 automatically when @code{direction} is set.
1693 The following example shows in bar 1 the default behavior of stems,
1694 with those on high notes pointing down and those on low notes pointing
1695 up, followed by four notes with all stems forced down, four notes with
1696 all stems forced up, and finally four notes reverted back to the
1699 @cindex Stem, example of overriding
1700 @cindex direction property, example
1702 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1704 \override Stem #'direction = #DOWN
1706 \override Stem #'direction = #UP
1708 \revert Stem #'direction
1712 Here we use the constants @code{DOWN} and @code{UP}.
1713 These have the values @code{-1} and @code{+1} respectively, and
1714 these numerical values may be used instead. The value @code{0}
1715 may also be used in some cases. It is simply treated as meaning
1716 @code{UP} for stems, but for some objects it means @q{center}.
1717 There is a constant, @code{CENTER} which has the value @code{0}.
1719 However, these explicit overrides are not usually used, as there are
1720 simpler equivalent predefined commands available. Here is a table of
1721 the commonest. The meaning of each is stated where it is not obvious.
1723 @multitable @columnfractions .2 .2 .25 .35
1728 @item @code{\arpeggioArrowDown}
1729 @tab @code{\arpeggioArrowUp}
1730 @tab @code{\arpeggioNormal}
1731 @tab Arrow is at bottom, at top, or no arrow
1732 @item @code{\dotsDown}
1734 @tab @code{\dotsNeutral}
1735 @tab Direction of movement to avoid staff lines
1736 @item @code{\dynamicDown}
1737 @tab @code{\dynamicUp}
1738 @tab @code{\dynamicNeutral}
1740 @item @code{\phrasingSlurDown}
1741 @tab @code{\phrasingSlurUp}
1742 @tab @code{\phrasingSlurNeutral}
1743 @tab Note: distinct from slur commands
1744 @item @code{\slurDown}
1746 @tab @code{\slurNeutral}
1748 @item @code{\stemDown}
1750 @tab @code{\stemNeutral}
1752 @item @code{\textSpannerDown}
1753 @tab @code{\textSpannerUp}
1754 @tab @code{\textSpannerNeutral}
1755 @tab Text entered as spanner is below/above staff
1756 @item @code{\tieDown}
1758 @tab @code{\tieNeutral}
1760 @item @code{\tupletDown}
1761 @tab @code{\tupletUp}
1762 @tab @code{\tupletNeutral}
1763 @tab Tuplets are below/above notes
1766 Note that these predefined commands may @strong{not} be
1767 preceded by @code{\once}. If you wish to limit the
1768 effect to a single note you must either use the equivalent
1769 @code{\once \override} command or use the predefined command
1770 followed after the affected note by the corresponding
1771 @code{\xxxNeutral} command.
1773 @unnumberedsubsubsec Fingering
1775 @cindex fingering, placement
1776 @cindex fingering, chords
1778 The placement of fingering on single notes can also be controlled
1779 by the @code{direction} property, but changing @code{direction}
1780 has no effect on chords. As we shall see, there are special
1781 commands which allow the fingering of individual notes
1782 of chords to be controlled, with the fingering being placed
1783 above, below, to the left or to the right of each note.
1785 First, here's the effect of @code{direction} on the fingering
1786 attached to single notes. The first bar shows the default
1787 behaviour, and the following two bars shows the effect of
1788 specifying @code{DOWN} and @code{UP}:
1790 @cindex Fingering, example of overriding
1791 @cindex direction property, example
1793 @lilypond[quote,verbatim,relative=2]
1795 \override Fingering #'direction = #DOWN
1797 \override Fingering #'direction = #UP
1801 However, overriding the @code{direction} property is not the
1802 easiest way of manually setting the fingering above or below
1803 the notes; using @code{_} or @code{^} instead of @code{-} before
1804 the fingering number is usually preferable. Here is the previous
1805 example using this method:
1807 @cindex fingering example
1809 @lilypond[quote,verbatim,relative=2]
1815 The @code{direction} property is ignored for chords, but the
1816 directional prefixes, @code{_} and @code{^} do work. By default,
1817 the fingering is automatically placed both above and below the
1818 notes of a chord, as shown:
1820 @cindex fingering example
1822 @lilypond[quote,verbatim,relative=2]
1829 but this may be overridden to manually force all or any of the
1830 individual fingering numbers above or below:
1832 @cindex fingering example
1834 @lilypond[quote,verbatim,relative=2]
1840 Even greater control over the placement of fingering of the
1841 individual notes in a chord is possible by using the
1842 @code{\set fingeringOrientations} command. The format of this
1846 @code{\set fingeringOrientations = #'([up] [left/right] [down])}
1850 @code{\set} is used because @code{fingeringOrientations} is a
1851 property of the @code{Voice} context, created and used by the
1852 @code{New_fingering_engraver}.
1854 The property may be set to a list of one to three values.
1855 It controls whether fingerings may be placed above (if
1856 @code{up} appears in the list), below (if @code{down} appears),
1857 to the left (if @code{left} appears, or to the right
1858 (if @code{right} appears). Conversely, if a location is not
1859 listed, no fingering is placed there. LilyPond takes these
1860 constraints and works out the best placement for the fingering
1861 of the notes of the following chords. Note that @code{left} and
1862 @code{right} are mutually exclusive -- fingering may be placed
1863 only on one side or the other, not both.
1865 @warning{To control the placement of the fingering of a single
1866 note using this command it is necessary to write it as a single
1867 note chord by placing angle brackets round it.}
1869 Here are a few examples:
1871 @cindex fingering example
1872 @cindex @code{\set}, example of using
1873 @cindex fingeringOrientations property, example
1875 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1876 \set fingeringOrientations = #'(left)
1878 < c-1 e-2 g-3 b-5 > 4
1879 \set fingeringOrientations = #'(left)
1881 < c-1 e-2 g-3 b-5 > 4
1882 \set fingeringOrientations = #'(up left down)
1884 < c-1 e-2 g-3 b-5 > 4
1885 \set fingeringOrientations = #'(up left)
1887 < c-1 e-2 g-3 b-5 > 4
1888 \set fingeringOrientations = #'(right)
1890 < c-1 e-2 g-3 b-5 > 4
1894 If the fingering seems a little crowded the @code{font-size}
1895 could be reduced. The default value can be seen from the
1896 @code{Fingering} object in the IR to be @code{-5}, so let's
1899 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1900 \override Fingering #'font-size = #-7
1901 \set fingeringOrientations = #'(left)
1903 < c-1 e-2 g-3 b-5 > 4
1904 \set fingeringOrientations = #'(left)
1906 < c-1 e-2 g-3 b-5 > 4
1907 \set fingeringOrientations = #'(up left down)
1909 < c-1 e-2 g-3 b-5 > 4
1910 \set fingeringOrientations = #'(up left)
1912 < c-1 e-2 g-3 b-5 > 4
1913 \set fingeringOrientations = #'(right)
1915 < c-1 e-2 g-3 b-5 > 4
1918 @node Outside-staff objects
1919 @subsection Outside-staff objects
1921 Outside-staff objects are automatically placed to avoid collisions.
1922 Objects with the lower value of the @code{outside-staff-priority}
1923 property are placed nearer to the staff, and other outside-staff
1924 objects are then raised as far as necessary to avoid collisions.
1925 The @code{outside-staff-priority} is defined in the
1926 @code{grob-interface} and so is a property of all layout objects.
1927 By default it is set to @code{#f} for all within-staff objects,
1928 and to a numerical value appropriate to each outside-staff object
1929 when the object is created. The following table shows the default
1930 numerical values for some of the commonest outside-staff objects
1931 which are, by default, placed in the @code{Staff} or @code{Voice}
1936 Note the unusual names for some of the objects: spanner objects
1937 are automatically created to control the vertical positioning of
1938 grobs which (might) start and end at different musical moments, so
1939 changing the @code{outside-staff-priority} of the underlying grob
1940 will have no effect. For example, changing
1941 @code{outside-staff-priority} of the @code{Hairpin} object will
1942 have no effect on the vertical positioning of hairpins -- you must
1943 change @code{outside-staff-priority} of the associated
1944 @code{DynamicLineSpanner} object instead. This override must be
1945 placed at the start of the spanner, which might include several
1946 linked hairpins and dynamics.
1948 @multitable @columnfractions .3 .3 .3
1949 @headitem Layout Object
1951 @tab Controls position of:
1952 @item @code{MultiMeasureRestText}
1954 @tab Text over full-bar rests
1955 @item @code{TextScript}
1958 @item @code{OttavaBracket}
1960 @tab Ottava brackets
1961 @item @code{TextSpanner}
1964 @item @code{DynamicLineSpanner}
1966 @tab All dynamic markings
1967 @item @code{VoltaBracketSpanner}
1970 @item @code{TrillSpanner}
1972 @tab Spanning trills
1975 Here is an example showing the default placement of some of
1978 @cindex text spanner
1979 @cindex ottava bracket
1981 @funindex \startTextSpan
1982 @funindex startTextSpan
1983 @funindex \stopTextSpan
1984 @funindex stopTextSpan
1986 @cindex TextSpanner, example of overriding
1987 @cindex bound-details property, example
1989 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1990 % Set details for later Text Spanner
1991 \override TextSpanner #'(bound-details left text)
1992 = \markup { \small \bold Slower }
1993 % Place dynamics above staff
1995 % Start Ottava Bracket
1998 % Add Dynamic Text and hairpin
2004 % Add Dynamic Text and terminate hairpin
2005 c\ff c \stopTextSpan
2006 % Stop Ottava Bracket
2011 This example also shows how to create Text Spanners --
2012 text with extender lines above a section of music. The
2013 spanner extends from the @code{\startTextSpan} command to
2014 the @code{\stopTextSpan} command, and the format of the
2015 text is defined by the @code{\override TextSpanner} command.
2016 For more details see @ruser{Text spanners}.
2018 It also shows how ottava brackets are created.
2020 @cindex tweaking bar number placement
2021 @cindex bar numbers, tweaking placement
2022 @cindex tweaking metronome mark placement
2023 @cindex metronome mark, tweaking placement
2024 @cindex tweaking rehearsal mark placement
2025 @cindex rehearsal marks, tweaking placement
2027 Note that bar numbers, metronome marks and rehearsal marks are not
2028 shown. By default these are created in the @code{Score} context and
2029 their @code{outside-staff-priority} is ignored relative to the layout
2030 objects which are created in the @code{Staff} context. If you wish to
2031 place bar numbers, metronome marks or rehearsal marks in accordance
2032 with the value of their @code{outside-staff-priority} the
2033 @code{Bar_number_engraver}, @code{Metronome_mark_engraver} or
2034 @code{Mark_engraver} respectively should be removed from the
2035 @code{Score} context and placed in the top @code{Staff} context. If
2036 this is done, these marks will be given the following default
2037 @code{outside-staff-priority} values:
2039 @multitable @columnfractions .3 .3
2040 @headitem Layout Object @tab Priority
2041 @item @code{RehearsalMark} @tab @code{1500}
2042 @item @code{MetronomeMark} @tab @code{1000}
2043 @item @code{BarNumber} @tab @code{ 100}
2046 If the default values of @code{outside-staff-priority} do not give you
2047 the placing you want, the priority of any of the objects may be
2048 overridden. Suppose we would like the ottava bracket to be placed
2049 below the text spanner in the example above. All we need to do is to
2050 look up the priority of @code{OttavaBracket} in the IR or in the
2051 tables above, and reduce it to a value lower than that of a
2052 @code{TextSpanner}, remembering that @code{OttavaBracket} is created
2053 in the @code{Staff} context:
2055 @cindex TextSpanner, example of overriding
2056 @cindex bound-details property, example
2058 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
2059 % Set details for later Text Spanner
2060 \override TextSpanner #'(bound-details left text)
2061 = \markup { \small \bold Slower }
2062 % Place dynamics above staff
2064 %Place following Ottava Bracket below Text Spanners
2065 \once \override Staff.OttavaBracket #'outside-staff-priority = #340
2066 % Start Ottava Bracket
2071 % Add Dynamic Line Spanner
2077 c\ff c \stopTextSpan
2078 % Stop Ottava Bracket
2083 @cindex slurs and outside-staff-priority
2084 @cindex slurs and articulations
2085 @cindex articulations and slurs
2087 Slurs by default are classed as within-staff objects, but
2088 they often appear above the staff if the notes to
2089 which they are attached are high on the staff. This can push
2090 outside-staff objects such as articulations too high, as the slur
2091 will be placed first. The @code{avoid-slur} property of the
2092 articulation can be set to @code{'inside} to bring the articulation
2093 inside the slur, but the @code{avoid-slur} property is effective
2094 only if the @code{outside-staff-priority} is also set to @code{#f}.
2095 Alternatively, the @code{outside-staff-priority} of the slur
2096 can be set to a numerical value to cause it to be placed along with
2097 other outside-staff objects according to that value. Here's an
2098 example showing the effect of the two methods:
2100 @lilypond[quote,verbatim,relative=2]
2101 c4( c^\markup\tiny\sharp d4.) c8
2103 \once \override TextScript #'avoid-slur = #'inside
2104 \once \override TextScript #'outside-staff-priority = ##f
2105 c^\markup\tiny\sharp d4.) c8
2106 \once \override Slur #'outside-staff-priority = #500
2107 c4( c^\markup\tiny\sharp d4.) c8
2110 Changing the @code{outside-staff-priority} can also be used to
2111 control the vertical placement of individual objects, although
2112 the results may not always be desirable. Suppose we would
2113 like @qq{Text3} to be placed above @qq{Text4} in the example
2114 under Automatic behavior, above (see @ref{Automatic behavior}).
2115 All we need to do is to look up the priority of @code{TextScript}
2116 in the IR or in the tables above, and increase the priority of
2117 @qq{Text3} to a higher value:
2119 @cindex TextScript, example of overriding
2120 @cindex outside-staff-priority property, example
2122 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2125 \once \override TextScript #'outside-staff-priority = #500
2130 This certainly lifts @qq{Text3} above @qq{Text4} but it also lifts it
2131 above @qq{Text2}, and @qq{Text4} now drops down. Perhaps this is not
2132 so good. What we would really like to do is to position all the
2133 annotation at the same distance above the staff. To do this, we
2134 clearly will need to space the notes out horizontally to make more
2135 room for the text. This is done using the @code{textLengthOn}
2138 @subheading \textLengthOn
2140 @cindex notes, spreading out with text
2142 @funindex \textLengthOn
2143 @funindex textLengthOn
2144 @funindex \textLengthOff
2145 @funindex textLengthOff
2147 By default, text produced by markup takes up no horizontal space
2148 as far as laying out the music is concerned. The @code{\textLengthOn}
2149 command reverses this behavior, causing the notes to be spaced
2150 out as far as is necessary to accommodate the text:
2152 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2153 \textLengthOn % Cause notes to space out to accommodate text
2160 The command to revert to the default behavior is
2161 @code{\textLengthOff}. Remember @code{\once} only works with
2162 @code{\override}, @code{\set}, @code{\revert} or @code{unset},
2163 so cannot be used with @code{\textLengthOn}.
2165 @cindex markup text, allowing collisions
2167 Markup text will also avoid notes which project above the staff.
2168 If this is not desired, the automatic displacement upwards may
2169 be turned off by setting the priority to @code{#f}. Here's an
2170 example to show how markup text interacts with such notes.
2172 @cindex TextScript, example of overriding
2173 @cindex outside-staff-priority property, example
2175 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2176 % This markup is short enough to fit without collision
2180 % This is too long to fit, so it is displaced upwards
2184 % Turn off collision avoidance
2185 \once \override TextScript #'outside-staff-priority = ##f
2189 % Turn off collision avoidance
2190 \once \override TextScript #'outside-staff-priority = ##f
2191 \textLengthOn % and turn on textLengthOn
2192 c,,2^"Long Text " % Spaces at end are honored
2197 @subheading Dynamics
2199 @cindex tweaking dynamics placement
2200 @cindex dynamics, tweaking placement
2202 Dynamic markings will normally be positioned beneath the
2203 staff, but may be positioned above with the @code{dynamicUp}
2204 command. They will be positioned vertically relative to the
2205 note to which they are attached, and will float below (or above)
2206 all within-staff objects such as phrasing slurs and bar numbers.
2207 This can give quite acceptable results, as this example
2210 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
2215 bes4.~\f\< \( bes4 bes8 des4\ff\> c16 bes\! |
2216 ees,2.~\)\mf ees4 r8 |
2219 However, if the notes and attached dynamics are close
2220 together the automatic placement will avoid collisions
2221 by displacing later dynamic markings further away, but this may
2222 not be the optimum placement, as this rather artificial example
2225 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2231 Should a similar situation arise in @q{real} music, it may be
2232 preferable to space out the notes a little further, so the dynamic
2233 markings can all fit at the same vertical distance from the staff. We
2234 were able to do this for markup text by using the @code{\textLengthOn}
2235 command, but there is no equivalent command for dynamic marks. So we
2236 shall have to work out how to do this using @code{\override} commands.
2238 @subheading Grob sizing
2241 @cindex sizing grobs
2243 First we must learn how grobs are sized. All grobs have a
2244 reference point defined within them which is used to position
2245 them relative to their parent object. This point in the grob
2246 is then positioned at a horizontal distance, @code{X-offset},
2247 and at a vertical distance, @code{Y-offset}, from its parent.
2248 The horizontal extent of the object is given by a pair of
2249 numbers, @code{X-extent}, which say where the left and right
2250 edges are relative to the reference point. The vertical extent
2251 is similarly defined by a pair of numbers, @code{Y-extent}.
2252 These are properties of all grobs which support the
2253 @code{grob-interface}.
2255 @cindex @code{extra-spacing-width}
2257 By default, outside-staff objects are given a width of zero so
2258 that they may overlap in the horizontal direction. This is done
2259 by the trick of adding infinity to the leftmost extent and
2260 minus infinity to the rightmost extent by setting the
2261 @code{extra-spacing-width} to @code{'(+inf.0 . -inf.0)}. So
2262 to ensure they do not overlap in the horizontal direction we
2263 must override this value of @code{extra-spacing-width} to
2264 @code{'(0 . 0)} so the true width shines through. This is
2265 the command to do this for dynamic text:
2268 \override DynamicText #'extra-spacing-width = #'(0 . 0)
2272 Let's see if this works in our previous example:
2274 @cindex DynamicText, example of overriding
2275 @cindex extra-spacing-width property, example
2277 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2279 \override DynamicText #'extra-spacing-width = #'(0 . 0)
2284 Well, it has certainly stopped the dynamic marks being
2285 displaced, but two problems remain. The marks should be
2286 spaced a little further apart and it would be better
2287 if they were all the same distance from the staff.
2288 We can solve the first problem easily. Instead of making
2289 the @code{extra-spacing-width} zero we could add a little
2290 more to it. The units are the space between two staff
2291 lines, so moving the left edge half a unit to the left and the
2292 right edge half a unit to the right should do it:
2294 @cindex DynamicText, example of overriding
2295 @cindex extra-spacing-width property, example
2297 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2299 % Extend width by 1 staff space
2300 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
2305 This looks better, but maybe we would prefer the dynamic marks
2306 to be aligned along the same baseline rather than going up and
2307 down with the notes. The property to do this is
2308 @code{staff-padding} which is covered in the following section.
2311 @node Collisions of objects
2312 @section Collisions of objects
2316 * Fixing overlapping notation::
2317 * Real music example::
2320 @node Moving objects
2321 @subsection Moving objects
2323 @cindex moving overlapping objects
2324 @cindex moving colliding objects
2325 @cindex moving colliding grobs
2326 @cindex objects, moving colliding
2327 @cindex grobs, moving colliding
2329 This may come as a surprise, but LilyPond is not perfect. Some
2330 notation elements can overlap. This is unfortunate, but in fact
2331 rather rare. Usually the need to move objects is for clarity or
2332 aesthetic reasons -- they would look better with a little more
2333 or a little less space around them.
2335 There are three main approaches to resolving overlapping
2336 notation. They should be considered in the following order:
2340 The @strong{direction} of one of the overlapping objects may
2341 be changed using the predefined commands listed above for
2342 within-staff objects (see @ref{Within-staff objects}).
2343 Stems, slurs, beams, ties, dynamics, text and tuplets may be
2344 repositioned easily in this way. The limitation is that you
2345 have a choice of only two positions, and neither may be
2349 The @strong{object properties}, which LilyPond uses when positioning
2350 layout objects, may be modified using @code{\override}. The
2351 advantages of making changes to this type of property are (a) that
2352 some other objects will be moved automatically if necessary to make
2353 room and (b) the single override can apply to all instances of the
2354 same type of object. Such properties include:
2361 This has already been covered in some detail -- see
2362 @ref{Within-staff objects}.
2365 @code{padding}, @code{left-padding},
2366 @code{right-padding}, @code{staff-padding}
2369 @cindex left-padding property
2370 @cindex padding property
2371 @cindex right-padding property
2372 @cindex staff-padding property
2374 As an object is being positioned the value of its @code{padding}
2375 property specifies the gap that must be left between itself and the
2376 nearest edge of the object against which it is being positioned. Note
2377 that it is the @code{padding} value of the object @strong{being
2378 placed} that is used; the @code{padding} value of the object which is
2379 already placed is ignored. Gaps specified by @code{padding} can be
2380 applied to all objects which support the
2381 @code{side-position-interface}.
2383 Instead of @code{padding}, the placement of groups of accidentals
2384 is controlled by @code{left-padding} and @code{right-padding}.
2385 These properties are to be found in the @code{AccidentalPlacement}
2386 object which, note, lives in the @strong{staff} context. In the
2387 type-setting process the note heads are type-set first and then
2388 the accidentals, if any, are added to the left of the note heads
2389 using the @code{right-padding} property to determine the separation
2390 from the note heads. So only the @code{right-padding} property of the
2391 @code{AccidentalPlacement} object has any effect on the placement
2394 The @code{staff-padding} property is closely related to the
2395 @code{padding} property: @code{padding} controls the minimum amount of
2396 space between any object which supports the
2397 @code{side-position-interface} and the nearest other object (generally
2398 the note or the staff lines); @code{staff-padding} applies only to
2399 those objects which are always set outside the staff -- it controls
2400 the minimum amount of space that should be inserted between that
2401 object and the staff. Note that @code{staff-padding} has no effect on
2402 objects which are positioned relative to the note rather than the
2403 staff, even though it may be overridden without error for such objects
2404 -- it is simply ignored.
2406 To discover which padding property is required for the object you wish
2407 to reposition, you need to return to the IR and look up the object's
2408 properties. Be aware that the padding properties might not be located
2409 in the obvious object, so look in objects that appear to be related.
2411 All padding values are measured in staff spaces. For most
2412 objects, this value is set by default to be around 1.0 or less
2413 (it varies with each object). It may be overridden if a larger
2414 (or smaller) gap is required.
2417 @code{self-alignment-X}
2419 @cindex self-alignment-X property
2421 This property can be used to align the object to the left, to
2422 the right, or to center it with respect to the parent object's
2423 reference point. It may be used with all objects which support
2424 the @code{self-alignment-interface}. In general these are objects
2425 that contain text. The values are @code{LEFT}, @code{RIGHT}
2426 or @code{CENTER}. Alternatively, a numerical value between
2427 @code{-1} and @code{+1} may be specified, where @code{-1} is
2428 left-aligned, @code{+1} is right-aligned, and numbers in between
2429 move the text progressively from left-aligned to right-aligned.
2430 Numerical values greater than @code{1} may be specified to move
2431 the text even further to the left, or less than @code{-1} to
2432 move the text even further to the right. A change of @code{1}
2433 in the value corresponds to a movement of half the text's length.
2436 @code{extra-spacing-width}
2438 @cindex extra-spacing-width property
2440 This property is available for all objects which support the
2441 @code{item-interface}. It takes two numbers, the first is added
2442 to the leftmost extent and the second is added to the rightmost
2443 extent. Negative numbers move the edge to the left, positive to
2444 the right, so to widen an object the first number must be negative,
2445 the second positive. Note that not all objects honor both
2446 numbers. For example, the @code{Accidental} object only takes
2447 notice of the first (left edge) number.
2450 @code{staff-position}
2452 @cindex staff-position property
2454 @code{staff-position} is a property of the
2455 @code{staff-symbol-referencer-interface}, which is supported by
2456 objects which are positioned relative to the staff. It specifies
2457 the vertical position of the object relative to the center line
2458 of the staff in half staff-spaces. It is useful in resolving
2459 collisions between layout objects like multi-measure rests, ties
2460 and notes in different voices.
2465 @cindex force-hshift property
2467 Closely spaced notes in a chord, or notes occurring at the same
2468 time in different voices, are arranged in two, occasionally more,
2469 columns to prevent the note heads overlapping. These are called
2470 note columns, and an object called @code{NoteColumn} is created
2471 to lay out the notes in that column.
2473 The @code{force-hshift} property is a property of a @code{NoteColumn}
2474 (actually of the @code{note-column-interface}). Changing it permits a
2475 note column to be moved in units appropriate to a note column,
2476 viz. the note head width of the first voice note. It should be used
2477 in complex situations where the normal @code{\shiftOn} commands (see
2478 @ref{Explicitly instantiating voices}) do not resolve the note
2479 conflict. It is preferable to the @code{extra-offset} property for
2480 this purpose as there is no need to work out the distance in
2481 staff-spaces, and moving the notes into or out of a @code{NoteColumn}
2482 affects other actions such as merging note heads.
2487 Finally, when all else fails, objects may be manually repositioned
2488 relative to the staff center line vertically, or by displacing them by
2489 any distance to a new position. The disadvantages are that the
2490 correct values for the repositioning have to be worked out, often by
2491 trial and error, for every object individually, and, because the
2492 movement is done after LilyPond has placed all other objects, the user
2493 is responsible for avoiding any collisions that might ensue. But the
2494 main difficulty with this approach is that the repositioning values
2495 may need to be reworked if the music is later modified. The
2496 properties that can be used for this type of manual repositioning are:
2501 @cindex extra-offset property
2503 This property applies to any layout object supporting the
2504 @code{grob-interface}. It takes a pair of numbers which specify the
2505 extra displacement in the horizontal and vertical directions.
2506 Negative numbers move the object to the left or down. The units are
2507 staff-spaces. The extra displacement is made after the typesetting of
2508 objects is finished, so an object may be repositioned anywhere without
2509 affecting anything else.
2513 @cindex positions property
2515 This is most useful for manually adjusting the slope and height
2516 of beams, slurs, and tuplets. It takes a pair of numbers
2517 giving the position of the left and right ends of the beam, slur,
2518 etc. relative to the center line of the staff. Units are
2519 staff-spaces. Note, though, that slurs and phrasing slurs cannot
2520 be repositioned by arbitrarily large amounts. LilyPond first
2521 generates a list of possible positions for the slur and by default
2522 finds the slur that @qq{looks best}. If the @code{positions}
2523 property has been overridden the slur that is closest to the
2524 requested positions is selected from the list.
2529 A particular object may not have all of these properties.
2530 It is necessary to go to the IR to look up which properties
2531 are available for the object in question.
2533 Here is a list of the objects which are most likely to be
2534 involved in collisions, together with the name of the object which
2535 should be looked up in the IR in order to discover which properties
2536 should be used to move them.
2538 @multitable @columnfractions .5 .5
2539 @headitem Object type @tab Object name
2540 @item Articulations @tab @code{Script}
2541 @item Beams @tab @code{Beam}
2542 @item Dynamics (vertically) @tab @code{DynamicLineSpanner}
2543 @item Dynamics (horizontally) @tab @code{DynamicText}
2544 @item Fingerings @tab @code{Fingering}
2545 @item Rehearsal / Text marks @tab @code{RehearsalMark}
2546 @item Slurs @tab @code{Slur}
2547 @item Text e.g. @code{^"text"} @tab @code{TextScript}
2548 @item Ties @tab @code{Tie}
2549 @item Tuplets @tab @code{TupletBracket}
2553 @node Fixing overlapping notation
2554 @subsection Fixing overlapping notation
2556 Let's now see how the properties in the previous section can
2557 help to resolve overlapping notation.
2559 @subheading padding property
2562 @cindex fixing overlapping notation
2563 @cindex overlapping notation
2565 The @code{padding} property can be set to increase
2566 (or decrease) the distance between symbols that are printed
2567 above or below notes.
2569 @cindex Script, example of overriding
2570 @cindex padding property, example
2572 @lilypond[quote,fragment,relative=1,verbatim]
2574 \override Script #'padding = #3
2578 @cindex MetronomeMark, example of overriding
2579 @cindex padding property, example
2581 @lilypond[quote,fragment,relative=1,verbatim]
2582 % This will not work, see below:
2583 \override MetronomeMark #'padding = #3
2587 \override Score.MetronomeMark #'padding = #3
2592 Note in the second example how important it is to figure out what
2593 context handles a certain object. Since the @code{MetronomeMark}
2594 object is handled in the @code{Score} context, property changes in the
2595 @code{Voice} context will not be noticed. For more details, see
2596 @ruser{Modifying properties}.
2598 If the @code{padding} property of an object is increased when that
2599 object is in a stack of objects being positioned according to
2600 their @code{outside-staff-priority}, then that object and all
2601 objects outside it are moved.
2604 @subheading left-padding and right-padding
2606 @cindex left-padding property
2607 @cindex right-padding property
2609 The @code{right-padding} property affects the spacing between the
2610 accidental and the note to which it applies. It is not often
2611 required, but the default spacing may be wrong for certain special
2612 accidental glyphs or combination of glyphs used in some microtonal
2613 music. These have to be entered by overriding the accidental
2614 stencil with a markup containing the desired symbol(s), like this:
2616 @cindex Accidental, example of overriding
2617 @cindex text property, example
2618 @cindex stencil property, example
2619 @cindex AccidentalPlacement, example of overriding
2620 @cindex right-padding property, example
2622 @lilypond[quote,ragged-right,verbatim]
2623 sesquisharp = \markup { \sesquisharp }
2626 % This prints a sesquisharp but the spacing is too small
2627 \once \override Accidental
2628 #'stencil = #ly:text-interface::print
2629 \once \override Accidental #'text = #sesquisharp
2631 % This improves the spacing
2632 \once \override Score.AccidentalPlacement #'right-padding = #0.6
2633 \once \override Accidental
2634 #'stencil = #ly:text-interface::print
2635 \once \override Accidental #'text = #sesquisharp
2641 This necessarily uses an override for the accidental stencil which
2642 will not be covered until later. The stencil type must be a
2643 procedure, here changed to print the contents of the @code{text}
2644 property of @code{Accidental}, which itself is set to be a
2645 sesquisharp sign. This sign is then moved further away from the
2646 note head by overriding @code{right-padding}.
2650 @subheading staff-padding property
2652 @cindex aligning objects on a baseline
2653 @cindex objects, aligning on a baseline
2655 @code{staff-padding} can be used to align objects such as dynamics
2656 along a baseline at a fixed height above the staff, rather than at a
2657 height dependent on the position of the note to which they are
2658 attached. It is not a property of @code{DynamicText} but of
2659 @code{DynamicLineSpanner}. This is because the baseline should apply
2660 equally to @strong{all} dynamics, including those created as extended
2661 spanners. So this is the way to align the dynamic marks in the
2662 example taken from the previous section:
2664 @cindex DynamicText, example of overriding
2665 @cindex extra-spacing-width property, example
2666 @cindex DynamicLineSpanner, example of overriding
2667 @cindex staff-padding property, example
2669 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2671 % Extend width by 1 unit
2672 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
2673 % Align dynamics to a base line 2 units above staff
2674 \override DynamicLineSpanner #'staff-padding = #2
2679 @subheading self-alignment-X property
2681 The following example shows how this can resolve the collision
2682 of a string fingering object with a note's stem by aligning the
2683 right edge with the reference point of the parent note:
2685 @cindex StringNumber, example of overriding
2686 @cindex self-alignment-X property, example
2688 @lilypond[quote,fragment,ragged-right,verbatim,relative=3]
2691 \once \override StringNumber #'self-alignment-X = #RIGHT
2695 @subheading staff-position property
2697 @cindex object collision within a staff
2699 Multimeasure rests in one voice can collide with notes in another.
2700 Since these rests are typeset centered between the bar lines, it
2701 would require significant effort for LilyPond to figure out which
2702 other notes might collide with it, since all the current collision
2703 handling between notes and between notes and rests is done only
2704 for notes and rests that occur at the same time. Here's an
2705 example of a collision of this type:
2707 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2708 << {c c c c} \\ {R1} >>
2711 The best solution here is to move the multimeasure rest down, since
2712 the rest is in voice two. The default in @code{\voiceTwo} (i.e. in
2713 the second voice of a @code{<<@{...@} \\ @{...@}>>} construct) is that
2714 @code{staff-position} is set to -4 for MultiMeasureRest, so we need to
2715 move it, say, four half-staff spaces down to @code{-8}.
2717 @cindex MultiMeasureRest, example of overriding
2718 @cindex staff-position property, example
2720 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2724 \override MultiMeasureRest #'staff-position = #-8
2729 This is better than using, for example, @code{extra-offset},
2730 because the ledger line above the rest is inserted automatically.
2732 @subheading extra-offset property
2734 @cindex positioning objects
2735 @cindex positioning grobs
2736 @cindex objects, positioning
2737 @cindex grobs, positioning
2739 The @code{extra-offset} property provides complete control over the
2740 positioning of an object both horizontally and vertically.
2742 In the following example, the second fingering is moved a little to
2743 the left, and 1.8 staff space downwards:
2745 @cindex Fingering, example of overriding
2746 @cindex extra-offset property, example
2748 @lilypond[quote,fragment,relative=1,verbatim]
2751 \once \override Fingering
2752 #'extra-offset = #'(-0.3 . -1.8)
2757 @subheading positions property
2759 @cindex controlling tuplets, slurs, phrasing slurs, and beams manually
2760 @cindex manually controlling tuplets, slurs, phrasing slurs, and beams
2761 @cindex tuplet beams, controlling manually
2762 @cindex slurs, controlling manually
2763 @cindex phrasing slurs, controlling manually
2764 @cindex beams, controlling manually
2766 The @code{positions} property allows the position and slope of
2767 tuplets, slurs, phrasing slurs and beams to be controlled manually.
2768 Here's an example which has an ugly phrasing slur due to its trying to
2769 avoid the slur on the acciaccatura.
2771 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2772 r4 \acciaccatura e8\( d8 c ~c d c d\)
2776 We could simply move the phrasing slur above the notes, and this
2777 would be the preferred solution:
2779 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2782 \acciaccatura e8\( d8 c ~c d c d\)
2786 But if there were some reason why this could not be done the
2787 other alternative would be to move the left end of the phrasing
2788 slur down a little using the @code{positions} property. This
2789 also resolves the rather nasty shape.
2791 @cindex PhrasingSlur, example of overriding
2792 @cindex positions property, example
2794 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2796 \once \override PhrasingSlur #'positions = #'(-4 . -3)
2798 e8\( d8 c ~c d c d\)
2801 Here's a further example taken from the opening of the left-hand
2802 staff of Chopin's Prelude Op 28 No. 2. We see that the beam
2803 collides with the upper notes:
2805 @lilypond[quote,verbatim,fragment,ragged-right]
2808 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2809 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2814 This can be resolved by manually moving both ends of the beam
2815 up from their position at 2 staff-spaces above the center line to,
2818 @cindex Beam, example of overriding
2819 @cindex positions property, example
2821 @lilypond[quote,verbatim,fragment,ragged-right]
2825 \override Beam #'positions = #'(3 . 3)
2830 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2835 Note that the override continues to apply in the first voice of
2836 the second block of quavers, but not to any of the beams in the
2839 @subheading force-hshift property
2841 @c FIXME: formatting stuff (ie not important right now IMO)
2842 @c @a nchor Chopin finally corrected TODOgp
2844 We can now see how to apply the final corrections to the Chopin
2845 example introduced at the end of @ref{I'm hearing Voices}, which
2846 was left looking like this:
2848 @lilypond[quote,verbatim,fragment,ragged-right]
2849 \new Staff \relative c'' {
2852 { c2 aes4. bes8 } \\
2864 The lower two notes of the first chord (i.e, those in the third voice)
2865 should not be shifted away from the note column of the higher two
2866 notes. To correct this we set @code{force-hshift}, which is a
2867 property of @code{NoteColumn}, of these notes to zero. The lower note
2868 of the second chord is best placed just to the right of the higher
2869 notes. We achieve this by setting @code{force-hshift} of this note to
2870 0.5, ie half a note head's width to the right of the note column of
2873 Here's the final result:
2875 @cindex NoteColumn, example of overriding
2876 @cindex force-hshift property, example
2878 @lilypond[quote,verbatim,fragment,ragged-right]
2879 \new Staff \relative c'' {
2882 { c2 aes4. bes8 } \\
2885 \once \override NoteColumn #'force-hshift = #0 <ees c>2
2886 \once \override NoteColumn #'force-hshift = #0.5 des2
2894 @node Real music example
2895 @subsection Real music example
2897 We end this section on Tweaks by showing the steps to be taken to
2898 deal with a tricky example which needs several tweaks to produce
2899 the desired output. The example has been deliberately chosen to
2900 illustrate the use of the Notation Reference to resolve unusual
2901 problems with notation. It is not representative of more usual
2902 engraving process, so please do not let these difficulties put
2903 you off! Fortunately, difficulties like these are not very common!
2905 The example is from Chopin's Première Ballade, Op. 23, bars 6 to
2906 9, the transition from the opening Lento to Moderato.
2907 Here, first, is what we want the output to look like, but to avoid
2908 over-complicating the example too much we have left out the
2909 dynamics, fingering and pedalling.
2911 @c The following should appear as music without code
2912 @c This example should not be indexed
2913 @c line-width ensures no break
2914 @lilypond[quote,ragged-right,line-width=5.5\in]
2915 rhMusic = \relative c'' {
2918 \once \override Tie #'staff-position = #3.5
2922 \mergeDifferentlyHeadedOn
2923 \mergeDifferentlyDottedOn
2924 bes2.^\markup {\bold "Moderato"} r8
2926 {c,8 d fis bes a | }
2928 % Reposition the c2 to the right of the merged note
2929 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
2930 % Move the c2 out of the main note column so the merge will work
2933 % Stem on the d2 must be down to permit merging
2934 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
2938 \mergeDifferentlyHeadedOff
2939 \mergeDifferentlyDottedOff
2943 lhMusic = \relative c' {
2945 <d g, d>1)\arpeggio |
2952 \new Staff = "RH" <<
2956 \new Staff = "LH" <<
2965 We note first that the right hand part in the third bar
2966 requires four voices. These are the five beamed eighth notes,
2967 the tied C, the half-note D which is merged with the eighth note
2968 D, and the dotted quarter note F-sharp, which is also merged with
2969 the eighth note at the same pitch. Everything else is in a single
2970 voice, so the easiest way is to introduce these four voices
2971 temporarily at the time they are needed. If you have forgotten
2972 how to do this, look at @ref{I'm hearing Voices}. Let us begin
2973 by entering the notes as two variables and setting up the staff
2974 structure in a score block, and see what LilyPond produces by
2977 @c line-width ensures no break
2978 @lilypond[quote,verbatim,ragged-right,line-width=5.5\in]
2979 rhMusic = \relative c'' {
2984 % Start polyphonic section of four voices
2986 {c,8 d fis bes a | }
2997 lhMusic = \relative c' {
3006 \new Staff = "RH" <<
3010 \new Staff = "LH" <<
3019 All the notes are right, but the appearance is far from
3020 satisfactory. The tie clashes with the change in time signature,
3021 the notes are not merged together, and several notation elements
3022 are missing. Let's first deal with the easier things. We can
3023 easily add the left hand slur and the right hand phrasing slur,
3024 since these were all covered in the Tutorial. Doing this gives:
3026 @c line-width ensures no break
3027 @lilypond[quote,verbatim,ragged-right,line-width=5.5\in]
3028 rhMusic = \relative c'' {
3033 % Start polyphonic section of four voices
3035 {c,8 d fis bes a | }
3046 lhMusic = \relative c' {
3055 \new Staff = "RH" <<
3059 \new Staff = "LH" <<
3068 The first bar is now correct. The second bar contains an arpeggio and
3069 is terminated by a double bar line. How do we do these, as they have
3070 not been mentioned in this Learning Manual? This is where we need to
3071 turn to the Notation Reference. Looking up @q{arpeggio} and @q{bar
3072 line} in the index quickly shows us that an arpeggio is produced by
3073 appending @code{\arpeggio} to a chord, and a double bar line is
3074 produced by the @code{\bar "||"} command. That's easily done. We
3075 next need to correct the collision of the tie with the time signature.
3076 This is best done by moving the tie upwards. Moving objects was
3077 covered earlier in @ref{Moving objects}, which says that objects
3078 positioned relative to the staff can be moved by overriding their
3079 @code{staff-position} property, which is specified in half staff
3080 spaces relative to the center line of the staff. So the following
3081 override placed just before the first tied note would move the tie up
3082 to 3.5 half staff spaces above the center line:
3084 @code{\once \override Tie #'staff-position = #3.5}
3086 This completes bar two, giving:
3088 @c line-width ensures no break
3089 @lilypond[quote,verbatim,ragged-right,line-width=5.5\in]
3090 rhMusic = \relative c'' {
3092 \once \override Tie #'staff-position = #3.5
3097 % Start polyphonic section of four voices
3099 {c,8 d fis bes a | }
3110 lhMusic = \relative c' {
3112 <d g, d>1)\arpeggio |
3119 \new Staff = "RH" <<
3123 \new Staff = "LH" <<
3132 On to bar three and the start of the Moderato section. The tutorial
3133 showed how to add embolded text with the @code{\markup} command, so
3134 adding @q{Moderato} in bold is easy. But how do we merge notes in
3135 different voices together? This is where we need to turn again to
3136 the Notation Reference for help. A search for @qq{merge} in the
3137 Notation Reference index quickly leads us to the commands for merging
3138 differently headed and differently dotted notes in @ruser{Collision
3139 resolution}. In our example we need to merge both types of note for
3140 the duration of the polyphonic section in bar 3, so using the
3141 information we find in the Notation Reference we add
3144 \mergeDifferentlyHeadedOn
3145 \mergeDifferentlyDottedOn
3149 to the start of that section and
3152 \mergeDifferentlyHeadedOff
3153 \mergeDifferentlyDottedOff
3159 @c line-width ensures no break
3160 @lilypond[quote,ragged-right,line-width=5.5\in]
3161 rhMusic = \relative c'' {
3163 \once \override Tie #'staff-position = #3.5
3167 bes2.^\markup {\bold "Moderato"} r8
3168 \mergeDifferentlyHeadedOn
3169 \mergeDifferentlyDottedOn
3170 % Start polyphonic section of four voices
3172 {c,8 d fis bes a | }
3180 \mergeDifferentlyHeadedOff
3181 \mergeDifferentlyDottedOff
3185 lhMusic = \relative c' {
3187 <d g, d>1)\arpeggio |
3194 \new Staff = "RH" <<
3198 \new Staff = "LH" <<
3207 These overrides have merged the two F-sharp notes, but not the two
3208 on D. Why not? The answer is there in the same section in the
3209 Notation Reference -- notes being merged must have stems in
3210 opposite directions and two notes cannot be merged successfully if
3211 there is a third note in the same note column. Here the two D's
3212 both have upward stems and there is a third note -- the C. We know
3213 how to change the stem direction using @code{\stemDown}, and
3214 the Notation Reference also says how to move the C -- apply a shift
3215 using one of the @code{\shift} commands. But which one?
3216 The C is in voice two which has shift off, and the two D's are in
3217 voices one and three, which have shift off and shift on,
3218 respectively. So we have to shift the C a further level still
3219 using @code{\shiftOnn} to avoid it interfering with the two D's.
3220 Applying these changes gives:
3222 @cindex Tie, example of overriding
3223 @cindex staff-position property, example
3225 @c line-width ensures no break
3226 @lilypond[quote,verbatim,ragged-right,line-width=5.5\in]
3227 rhMusic = \relative c'' {
3229 \once \override Tie #'staff-position = #3.5
3233 bes2.^\markup {\bold "Moderato"} r8
3234 \mergeDifferentlyHeadedOn
3235 \mergeDifferentlyDottedOn
3236 % Start polyphonic section of four voices
3238 {c,8 d fis bes a | }
3240 % Move the c2 out of the main note column so the merge will work
3241 {c,8~ \shiftOnn c2 | }
3243 % Stem on the d2 must be down to permit merging
3244 {s8 \stemDown d2 | }
3248 \mergeDifferentlyHeadedOff
3249 \mergeDifferentlyDottedOff
3253 lhMusic = \relative c' {
3255 <d g, d>1)\arpeggio |
3262 \new Staff = "RH" <<
3266 \new Staff = "LH" <<
3275 Nearly there. Only two problems remain: The downward stem on the
3276 merged D should not be there, and the C would be better positioned
3277 to the right of the D's. We know how to do both of these from the
3278 earlier tweaks: we make the stem transparent, and move the C with
3279 the @code{force-hshift} property. Here's the final result:
3281 @cindex NoteColumn, example of overriding
3282 @cindex force-hshift property, example
3283 @cindex Stem, example of overriding
3284 @cindex transparent property, example
3286 @c line-width ensures no break
3287 @lilypond[quote,verbatim,ragged-right,line-width=5.5\in]
3288 rhMusic = \relative c'' {
3291 \once \override Tie #'staff-position = #3.5
3295 bes2.^\markup {\bold "Moderato"} r8
3296 \mergeDifferentlyHeadedOn
3297 \mergeDifferentlyDottedOn
3299 {c,8 d fis bes a | }
3301 % Reposition the c2 to the right of the merged note
3302 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
3303 % Move the c2 out of the main note column so the merge will work
3306 % Stem on the d2 must be down to permit merging
3307 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
3311 \mergeDifferentlyHeadedOff
3312 \mergeDifferentlyDottedOff
3316 lhMusic = \relative c' {
3318 <d g, d>1)\arpeggio |
3325 \new Staff = "RH" <<
3329 \new Staff = "LH" <<
3339 @node Further tweaking
3340 @section Further tweaking
3343 * Other uses for tweaks::
3344 * Using variables for tweaks::
3346 * Other sources of information::
3347 * Avoiding tweaks with slower processing::
3348 * Advanced tweaks with Scheme::
3351 @node Other uses for tweaks
3352 @subsection Other uses for tweaks
3354 @cindex transparent property, use of
3355 @cindex objects, making invisible
3356 @cindex removing objects
3357 @cindex objects, removing
3358 @cindex hiding objects
3359 @cindex objects, hiding
3360 @cindex invisible objects
3361 @cindex objects, invisible
3362 @cindex tying notes across voices
3364 @subheading Tying notes across voices
3366 The following example demonstrates how to connect notes in
3367 different voices using ties. Normally, only two notes in the
3368 same voice can be connected with ties. By using two voices,
3369 with the tied notes in one of them
3371 @lilypond[quote,fragment,relative=2]
3372 << { b8~ b8\noBeam }
3378 and blanking the first up-stem in that voice, the tie appears to
3381 @cindex Stem, example of overriding
3382 @cindex transparent property, example
3384 @lilypond[quote,fragment,relative=2,verbatim]
3387 \once \override Stem #'transparent = ##t
3395 To make sure that the just-blanked stem doesn't squeeze the tie
3396 too much, we can lengthen the stem by setting the
3397 @code{length} to @code{8},
3399 @lilypond[quote,fragment,relative=2,verbatim]
3402 \once \override Stem #'transparent = ##t
3403 \once \override Stem #'length = #8
3411 @subheading Simulating a fermata in MIDI
3413 @cindex stencil property, use of
3414 @cindex fermata, implementing in MIDI
3416 For outside-staff objects it is usually better to override the
3417 object's @code{stencil} property rather than its @code{transparent}
3418 property when you wish to remove it from the printed output.
3419 Setting the @code{stencil} property of an object to @code{#f} will
3420 remove that object entirely from the printed output. This means it
3421 has no effect on the placement of other objects placed relative to
3424 For example, if we wished to change the metronome setting in order
3425 to simulate a fermata in the MIDI output we would not want the
3426 metronome markings to appear in the printed output, and we would
3427 not want it to influence the spacing between the two systems or
3428 the positions of adjacent annotations on the staff. So setting
3429 its @code{stencil} property to @code{#f} would be the best way.
3430 We show here the effect of the two methods:
3432 @cindex MetronomeMark, example of overriding
3433 @cindex transparent property, example
3435 @lilypond[quote,verbatim,ragged-right]
3438 % Visible tempo marking
3441 \once \override Score.MetronomeMark #'transparent = ##t
3442 % Invisible tempo marking to lengthen fermata in MIDI
3445 % New tempo for next section
3454 @cindex MetronomeMark, example of overriding
3455 @cindex stencil property, example
3457 @lilypond[quote,verbatim,ragged-right]
3460 % Visible tempo marking
3463 \once \override Score.MetronomeMark #'stencil = ##f
3464 % Invisible tempo marking to lengthen fermata in MIDI
3467 % New tempo for next section
3477 Both methods remove the metronome mark which lengthens the fermata
3478 from the printed output, and both affect the MIDI timing as
3479 required, but the transparent metronome mark in the first line
3480 forces the following tempo indication too high while the
3481 second (with the stencil removed) does not.
3483 @node Using variables for tweaks
3484 @subsection Using variables for tweaks
3486 @cindex variables, using for tweaks
3487 @cindex using variables for tweaks
3488 @cindex tweaks, using variables for
3490 Override commands are often long and tedious to type, and they
3491 have to be absolutely correct. If the same overrides are to be
3492 used many times it may be worth defining variables to hold them.
3494 Suppose we wish to emphasize certain words in lyrics by printing
3495 them in bold italics. The @code{\italic} and @code{\bold}
3496 commands only work within lyrics if they are embedded, together with
3497 the word or words to be modified, within a @code{\markup} block,
3498 which makes them tedious to enter. The need to embed the words
3499 themselves prevents their use in simple variables. As an
3500 alternative can we use @code{\override} and @code{\revert} commands?
3503 @code{\override Lyrics . LyricText #'font-shape = #'italic}
3504 @code{\override Lyrics . LyricText #'font-series = #'bold}
3506 @code{\revert Lyrics . LyricText #'font-shape}
3507 @code{\revert Lyrics . LyricText #'font-series}
3510 These would also be extremely tedious to enter if there were many
3511 words requiring emphasis. But we @emph{can} define these as two
3512 variables and use those to bracket the words to be emphasized.
3513 Another advantage of using variables for these overrides is that
3514 the spaces around the dot are not necessary, since they are not
3515 being interpreted in @code{\lyricmode} directly. Here's an example
3516 of this, although in practice we would choose shorter names
3517 for the variables to make them quicker to type:
3519 @cindex LyricText, example of overriding
3520 @cindex font-shape property, example
3521 @cindex font-series property, example
3523 @lilypond[quote,verbatim]
3525 \override Lyrics.LyricText #'font-shape = #'italic
3526 \override Lyrics.LyricText #'font-series = #'bold
3529 \revert Lyrics.LyricText #'font-shape
3530 \revert Lyrics.LyricText #'font-series
3533 global = { \time 4/4 \partial 4 \key c \major}
3534 SopranoMusic = \relative c' { c4 | e4. e8 g4 g | a a g }
3535 AltoMusic = \relative c' { c4 | c4. c8 e4 e | f f e }
3536 TenorMusic = \relative c { e4 | g4. g8 c4. b8 | a8 b c d e4 }
3537 BassMusic = \relative c { c4 | c4. c8 c4 c | f8 g a b c4 }
3538 VerseOne = \lyrics { E -- | ter -- nal \emphasize Fa -- ther, \normal | strong to save, }
3539 VerseTwo = \lyricmode { O | \emphasize Christ, \normal whose voice the | wa -- ters heard, }
3540 VerseThree = \lyricmode { O | \emphasize Ho -- ly Spi -- rit, \normal | who didst brood }
3541 VerseFour = \lyricmode { O | \emphasize Tri -- ni -- ty \normal of | love and pow'r }
3547 \new Voice = "Soprano" { \voiceOne \global \SopranoMusic }
3548 \new Voice = "Alto" { \voiceTwo \AltoMusic }
3549 \new Lyrics \lyricsto "Soprano" { \VerseOne }
3550 \new Lyrics \lyricsto "Soprano" { \VerseTwo }
3551 \new Lyrics \lyricsto "Soprano" { \VerseThree }
3552 \new Lyrics \lyricsto "Soprano" { \VerseFour }
3556 \new Voice = "Tenor" { \voiceOne \TenorMusic }
3557 \new Voice = "Bass" { \voiceTwo \BassMusic }
3565 @subsection Style sheets
3567 The output that LilyPond produces can be heavily modified; see
3568 @ref{Tweaking output}, for details. But what if you have many
3569 input files that you want to apply your tweaks to? Or what if you
3570 simply want to separate your tweaks from the actual music? This
3571 is quite easy to do.
3573 Let's look at an example. Don't worry if you don't understand
3574 the parts with all the @code{#()}. This is explained in
3575 @ref{Advanced tweaks with Scheme}.
3577 @lilypond[quote,verbatim,ragged-right]
3578 mpdolce = #(make-dynamic-script (markup #:hspace 0 #:translate '(5 . 0)
3579 #:line(#:dynamic "mp" #:text #:italic "dolce" )))
3581 inst = #(define-music-function (parser location string) (string?)
3585 'text (markup #:bold (#:box string))))
3589 a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
3591 cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
3595 There are some problems with overlapping output; we'll fix those using
3596 the techniques in @ref{Moving objects}. But let's also
3597 do something about the @code{mpdolce} and @code{inst}
3598 definitions. They produce the output we desire, but we might want
3599 to use them in another piece. We could simply copy-and-paste them
3600 at the top of every file, but that's an annoyance. It also leaves
3601 those definitions in our input files, and I personally find all
3602 the @code{#()} somewhat ugly. Let's hide them in another file:
3605 %%% save this to a file called "definitions.ily"
3606 mpdolce = #(make-dynamic-script (markup #:hspace 0 #:translate '(5 . 0)
3607 #:line(#:dynamic "mp" #:text #:italic "dolce" )))
3609 inst = #(define-music-function (parser location string) (string?)
3613 'text (markup #:bold (#:box string))))
3616 We will refer to this file using the @code{\include} command near
3617 the top of the music file. (The extension @code{.ily} is used to
3618 distinguish this included file, which is not meant to be compiled
3619 on its own, from the main file.)
3620 Now let's modify our music (let's save this file as @file{"music.ly"}).
3622 @c We have to do this awkward example/lilypond-non-verbatim
3623 @c because we can't do the \include stuff in the manual.
3626 \include "definitions.ily"
3630 a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
3632 cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
3636 @lilypond[quote,ragged-right]
3637 mpdolce = #(make-dynamic-script (markup #:hspace 0 #:translate '(5 . 0)
3638 #:line(#:dynamic "mp" #:text #:italic "dolce" )))
3640 inst = #(define-music-function (parser location string) (string?)
3644 'text (markup #:bold (#:box string))))
3648 a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
3650 cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
3654 That looks better, but let's make a few changes. The glissando is hard
3655 to see, so let's make it thicker and closer to the note heads. Let's
3656 put the metronome marking above the clef, instead of over the first
3657 note. And finally, my composition professor hates @q{C} time signatures,
3658 so we'd better make that @q{4/4} instead.
3660 Don't change @file{music.ly}, though. Replace our @file{definitions.ily}
3665 mpdolce = #(make-dynamic-script (markup #:hspace 0 #:translate '(5 . 0)
3666 #:line( #:dynamic "mp" #:text #:italic "dolce" )))
3668 inst = #(define-music-function (parser location string) (string?)
3672 'text (markup #:bold (#:box string))))
3676 \override MetronomeMark #'extra-offset = #'(-9 . 0)
3677 \override MetronomeMark #'padding = #'3
3680 \override TimeSignature #'style = #'numbered
3683 \override Glissando #'thickness = #3
3684 \override Glissando #'gap = #0.1
3689 @lilypond[quote,ragged-right]
3690 mpdolce = #(make-dynamic-script (markup #:hspace 0 #:translate '(5 . 0)
3691 #:line( #:dynamic "mp" #:text #:italic "dolce" )))
3693 inst = #(define-music-function (parser location string) (string?)
3697 'text (markup #:bold (#:box string))))
3701 \override MetronomeMark #'extra-offset = #'(-9 . 0)
3702 \override MetronomeMark #'padding = #'3
3705 \override TimeSignature #'style = #'numbered
3708 \override Glissando #'thickness = #3
3709 \override Glissando #'gap = #0.1
3715 a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
3717 cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
3721 That looks nicer! But now suppose that I want to publish this
3722 piece. My composition professor doesn't like @q{C} time
3723 signatures, but I'm somewhat fond of them. Let's copy the
3724 current @file{definitions.ily} to @file{web-publish.ily} and
3725 modify that. Since this music is aimed at producing a pdf which
3726 will be displayed on the screen, we'll also increase the
3727 overall size of the output.
3731 mpdolce = #(make-dynamic-script (markup #:hspace 0 #:translate '(5 . 0)
3732 #:line( #:dynamic "mp" #:text #:italic "dolce" )))
3734 inst = #(define-music-function (parser location string) (string?)
3738 'text (markup #:bold (#:box string))))
3740 #(set-global-staff-size 23)
3743 \override MetronomeMark #'extra-offset = #'(-9 . 0)
3744 \override MetronomeMark #'padding = #'3
3749 \override Glissando #'thickness = #3
3750 \override Glissando #'gap = #0.1
3755 @lilypond[quote,ragged-right]
3756 mpdolce = #(make-dynamic-script (markup #:hspace 0 #:translate '(5 . 0)
3757 #:line( #:dynamic "mp" #:text #:italic "dolce" )))
3759 inst = #(define-music-function (parser location string) (string?)
3763 'text (markup #:bold (#:box string))))
3765 #(set-global-staff-size 23)
3768 \override MetronomeMark #'extra-offset = #'(-9 . 0)
3769 \override MetronomeMark #'padding = #'3
3772 \override Glissando #'thickness = #3
3773 \override Glissando #'gap = #0.1
3779 a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
3781 cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
3785 Now in our music, I simply replace
3786 @code{\include "definitions.ily"} with
3787 @code{\include "web-publish.ily"}. Of course, we could make this
3788 even more convenient. We could make a @file{definitions.ily} file which
3789 contains only the definitions of @code{mpdolce} and @code{inst}, a
3790 @file{web-publish.ily} file which contains only the @code{\layout}
3791 section listed above, and a @file{university.ily} file which
3792 contains only the tweaks to produce the output that my professor
3793 prefers. The top of @file{music.ly} would then look like this:
3796 \include "definitions.ily"
3798 %%% Only uncomment one of these two lines!
3799 \include "web-publish.ily"
3800 %\include "university.ily"
3803 This approach can be useful even if you are only producing
3804 one set of parts. I use half a dozen different
3805 @q{style sheet} files for my projects. I begin every music
3806 file with @code{\include "../global.ily"}, which contains
3810 \version @w{"@version{}"}
3811 #(ly:set-option 'point-and-click #f)
3812 \include "../init/init-defs.ly"
3813 \include "../init/init-layout.ly"
3814 \include "../init/init-headers.ly"
3815 \include "../init/init-paper.ly"
3819 @node Other sources of information
3820 @subsection Other sources of information
3822 The Internals Reference documentation contains a lot of information
3823 about LilyPond, but even more information can be gathered by
3824 looking at the internal LilyPond files. To explore these, you must
3825 first find the directory appropriate to your system. The location
3826 of this directory depends (a) on whether you obtained LilyPond
3827 by downloading a precompiled binary from lilypond.org
3828 or whether you installed it from a package manager (i.e.
3829 distributed with Linux, or installed under fink or cygwin) or
3830 compiled it from source, and (b) on which operating system it is
3833 @strong{Downloaded from lilypond.org}
3839 @file{@var{INSTALLDIR}/lilypond/usr/share/lilypond/current/}
3844 @file{@var{INSTALLDIR}/LilyPond.app/Contents/Resources/share/lilypond/current/}
3845 by either @code{cd}-ing into this directory from the
3846 Terminal, or control-clicking on the LilyPond application and
3847 selecting @q{Show Package Contents}.
3851 Using Windows Explorer, navigate to
3852 @file{@var{INSTALLDIR}/LilyPond/usr/share/lilypond/current/}
3856 @strong{Installed from a package manager or compiled from source}
3859 @file{@var{PREFIX}/share/lilypond/@var{X.Y.Z}/}, where
3860 @var{PREFIX} is set by your package manager or @code{configure}
3861 script, and @var{X.Y.Z} is the LilyPond version number.
3865 Within this directory the two interesting subdirectories are
3868 @item @file{ly/} - contains files in LilyPond format
3869 @item @file{scm/} - contains files in Scheme format
3872 Let's begin by looking at some files in @file{ly/}.
3873 Open @file{ly/property-init.ly} in a text editor. The one
3874 you normally use for @code{.ly} files will be fine. This file
3875 contains the definitions of all the standard LilyPond predefined
3876 commands, such as @code{\stemUp} and @code{\slurDotted}. You will
3877 see that these are nothing more than definitions of variables
3878 containing one or a group of @code{\override} commands. For
3879 example, @code{/tieDotted} is defined to be:
3883 \override Tie #'dash-period = #0.75
3884 \override Tie #'dash-fraction = #0.1
3888 If you do not like the default values these predefined commands can
3889 be redefined easily, just like any other variable, at the
3890 head of your input file.
3892 The following are the most useful files to be found in
3895 @multitable @columnfractions .4 .6
3898 @item @file{ly/engraver-init.ly}
3899 @tab Definitions of engraver Contexts
3900 @item @file{ly/paper-defaults-init.ly}
3901 @tab Specifications of paper-related defaults
3902 @item @file{ly/performer-init.ly}
3903 @tab Definitions of performer Contexts
3904 @item @file{ly/property-init.ly}
3905 @tab Definitions of all common predefined commands
3906 @item @file{ly/spanner-init.ly}
3907 @tab Definitions of spanner-related predefined commands
3910 Other settings (such as the definitions of markup commands) are
3911 stored as @code{.scm} (Scheme) files. The Scheme programming
3912 language is used to provide a programmable interface into
3913 LilyPond internal operation. Further explanation of these files
3914 is currently outside the scope of this manual, as a knowledge of
3915 the Scheme language is required. Users should be warned that
3916 a substantial amount of technical knowledge or time is required
3917 to understand Scheme and these files (see @rextend{Scheme tutorial}).
3919 If you have this knowledge, the Scheme files which may be of
3922 @multitable @columnfractions .4 .6
3925 @item @file{scm/auto-beam.scm}
3926 @tab Sub-beaming defaults
3927 @item @file{scm/define-grobs.scm}
3928 @tab Default settings for grob properties
3929 @item @file{scm/define-markup-commands.scm}
3930 @tab Specify all markup commands
3931 @item @file{scm/midi.scm}
3932 @tab Default settings for MIDI output
3933 @item @file{scm/output-lib.scm}
3934 @tab Settings that affect appearance of frets, colors,
3935 accidentals, bar lines, etc
3936 @item @file{scm/parser-clef.scm}
3937 @tab Definitions of supported clefs
3938 @item @file{scm/script.scm}
3939 @tab Default settings for articulations
3944 @node Avoiding tweaks with slower processing
3945 @subsection Avoiding tweaks with slower processing
3947 LilyPond can perform extra checks while it processes input files.
3948 These checks will take extra time to perform, but fewer manual tweaks
3949 may be required to obtain an acceptable result. If a text script
3950 or part of the lyrics extends over the margins these checks will
3951 compress that line of the score just enough to fit within the
3954 To be effective under all circumstances these checks must be enabled
3955 by placing the overrides in a Score @code{\with} block, rather than
3956 in-line in music, as follows:
3960 % Makes sure text scripts and lyrics are within the paper margins
3961 \override PaperColumn #'keep-inside-line = ##t
3962 \override NonMusicalPaperColumn #'keep-inside-line = ##t
3968 However, @code{keep-inside-line} is expensive and the recommendation
3969 is to not enable it, to allow for faster processing, until creating
3970 a final version. This way you do not need to manually add @code{\break}
3971 commands to avoid text running off the right-hand side of the page.
3973 @node Advanced tweaks with Scheme
3974 @subsection Advanced tweaks with Scheme
3976 Although many things are possible with the @code{\override} and
3977 @code{\tweak} commands, an even more powerful way of modifying
3978 the action of LilyPond is available through a programmable
3979 interface to the LilyPond internal operation. Code written in
3980 the Scheme programming language can be incorporated directly in
3981 the internal operation of LilyPond. Of course, at least a basic
3982 knowledge of programming in Scheme is required to do this, and an
3983 introduction is provided in the @rextend{Scheme tutorial}.
3985 As an illustration of one of the many possibilities, instead of
3986 setting a property to a constant it can be set to a Scheme
3987 procedure which is then called whenever that property is accessed
3988 by LilyPond. The property can then be set dynamically to a value
3989 determined by the procedure at the time it is called. In this
3990 example we color the note head in accordance with its position on
3993 @cindex x11-color function, example of using
3994 @cindex NoteHead, example of overriding
3995 @cindex color property, setting to Scheme procedure
3997 @lilypond[quote,verbatim,ragged-right]
3998 #(define (color-notehead grob)
3999 "Color the notehead according to its position on the staff."
4000 (let ((mod-position (modulo (ly:grob-property grob 'staff-position) 7)))
4002 ;; Return rainbow colors
4003 ((1) (x11-color 'red )) ; for C
4004 ((2) (x11-color 'orange )) ; for D
4005 ((3) (x11-color 'yellow )) ; for E
4006 ((4) (x11-color 'green )) ; for F
4007 ((5) (x11-color 'blue )) ; for G
4008 ((6) (x11-color 'purple )) ; for A
4009 ((0) (x11-color 'violet )) ; for B
4015 % Arrange to obtain color from color-notehead procedure
4016 \override NoteHead #'color = #color-notehead
4024 Further examples showing the use of these programmable interfaces
4025 can be found in @rextend{Tweaking with Scheme}.