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2 @c This file is part of lilypond-learning.tely
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13 @chapter Tweaking output
15 This chapter discusses how to modify output. LilyPond is extremely
16 configurable; virtually every fragment of output may be changed.
21 * The Internals Reference manual::
22 * Appearance of objects::
23 * Placement of objects::
24 * Collisions of objects::
29 @section Tweaking basics
32 * Introduction to tweaks::
33 * Objects and interfaces::
34 * Naming conventions of objects and properties::
38 @node Introduction to tweaks
39 @subsection Introduction to tweaks
41 @q{Tweaking} is a LilyPond term for the various methods available
42 to the user for modifying the actions taken during interpretation
43 of the input file and modifying the appearance of the printed
44 output. Some tweaks are very easy to use; others are more
45 complex. But taken together the methods available for tweaking
46 permit almost any desired appearance of the printed music to be
49 In this section we cover the basic concepts required to understand
50 tweaking. Later we give a variety of ready-made commands which can
51 simply be copied to obtain the same effect in your own scores, and
52 at the same time we show how these commands may be constructed so
53 that you may learn how to develop your own tweaks.
55 Before starting on this Chapter you may wish to review the section
56 @ref{Contexts and engravers}, as Contexts, Engravers, and the
57 Properties contained within them are fundamental to understanding
58 and constructing Tweaks.
60 @node Objects and interfaces
61 @subsection Objects and interfaces
67 @cindex properties, object
68 @cindex object properties
70 @cindex object, layout
73 Tweaking involves modifying the internal operation and structures
74 of the LilyPond program, so we must first introduce some terms
75 which are used to describe those internal operations and
78 The term @q{Object} is a generic term used to refer to the
79 multitude of internal structures built by LilyPond during the
80 processing of an input file. So when a command like @code{\new
81 Staff} is encountered a new object of type @code{Staff} is
82 constructed. That @code{Staff} object then holds all the
83 properties associated with that particular staff, for example, its
84 name and its key signature, together with details of the engravers
85 which have been assigned to operate within that staff's context.
86 Similarly, there are objects to hold the properties of all other
87 contexts, such as @code{Voice} objects, @code{Score} objects,
88 @code{Lyrics} objects, as well as objects to represent all
89 notational elements such as bar lines,
90 note heads, ties, dynamics, etc. Every object has its own set of
93 Some types of object are given special names. Objects which represent
94 items of notation on the printed output such as note heads, stems,
95 slurs, ties, fingering, clefs, etc are called @q{Layout objects},
96 often known as @q{Graphical Objects}, or @q{Grobs} for short. These
97 are still objects in the generic sense above, and so they too all have
98 properties associated with them, such as their position, size, color,
101 Some layout objects are still more specialized. Phrasing slurs,
102 crescendo hairpins, ottava marks, and many other grobs are not
103 localized in a single place -- they have a starting point, an
104 ending point, and maybe other properties concerned with their
105 shape. Objects with an extended shape like these are called
108 It remains to explain what @q{Interfaces} are. Many objects, even
109 though they are quite different, share common features which need to
110 be processed in the same way. For example, all grobs have a color, a
111 size, a position, etc, and all these properties are processed in the
112 same way during LilyPond's interpretation of the input file. To
113 simplify these internal operations these common actions and properties
114 are grouped together in an object called a @code{grob-interface}.
115 There are many other groupings of common properties like this, each
116 one given a name ending in @code{interface}. In total there are over
117 100 such interfaces. We shall see later why this is of interest and
120 These, then, are the main terms relating to objects which we
121 shall use in this chapter.
123 @node Naming conventions of objects and properties
124 @subsection Naming conventions of objects and properties
126 @cindex naming conventions for objects
127 @cindex naming conventions for properties
128 @cindex objects, naming conventions
129 @cindex properties, naming conventions
131 We met some object naming conventions previously, in
132 @ref{Contexts and engravers}. Here for reference is a list
133 of the most common object and property types together with
134 the conventions for naming them and a couple of examples of
135 some real names. We have used @q{A} to stand for any capitalized
136 alphabetic character and @q{aaa} to stand for any number of
137 lower-case alphabetic characters. Other characters are used
140 @multitable @columnfractions .33 .33 .33
141 @headitem Object/property type
142 @tab Naming convention
145 @tab Aaaa or AaaaAaaaAaaa
146 @tab Staff, GrandStaff
148 @tab Aaaa or AaaaAaaaAaaa
151 @tab Aaaa_aaa_engraver
152 @tab Clef_engraver, Note_heads_engraver
154 @tab aaa-aaa-interface
155 @tab grob-interface, break-aligned-interface
156 @item Context Properties
157 @tab aaa or aaaAaaaAaaa
158 @tab alignAboveContext, skipBars
159 @item Layout Object Properties
160 @tab aaa or aaa-aaa-aaa
161 @tab direction, beam-thickness
164 As we shall see shortly, the properties of different types of
165 object are modified by different commands, so it is useful to
166 be able to recognize the type of object from the names of its
170 @node Tweaking methods
171 @subsection Tweaking methods
173 @cindex tweaking methods
175 @strong{\override command}
177 @cindex override command
178 @cindex override syntax
183 We have already met the commands @code{\set} and @code{\with}, used to
184 change the properties of @strong{contexts} and to remove and add
185 @strong{engravers}, in @ref{Modifying context properties}, and
186 @ref{Adding and removing engravers}. We now must meet some more
189 The command to change the properties of @strong{layout objects} is
190 @code{\override}. Because this command has to modify
191 internal properties deep within LilyPond its syntax is not
192 as simple as the commands you have met so far. It needs to
193 know precisely which property of which object in which context
194 has to be modified, and what its new value is to be. Let's see
197 The general syntax of this command is:
200 \override @var{Context}.@var{LayoutObject} #'@var{layout-property} =
205 This will set the property with the name @var{layout-property} of the
206 layout object with the name @var{LayoutObject}, which is a member of
207 the @var{Context} context, to the value @var{value}.
209 The @var{Context} can be omitted (and usually is) when the
210 required context is unambiguously implied and is one of lowest
211 level contexts, i.e., @code{Voice}, @code{ChordNames} or
212 @code{Lyrics}, and we shall omit it in many of the following
213 examples. We shall see later when it must be specified.
215 Later sections deal comprehensively with properties and their
216 values, but to illustrate the format and use of these commands
217 we shall use just a few simple properties and values which are
220 For now, don't worry about the @code{#'}, which must precede the
221 layout property, and the @code{#}, which must precede the value.
222 These must always be present in exactly this form. This is the
223 most common command used in tweaking, and most of the rest of
224 this chapter will be directed to presenting examples of how it is
225 used. Here is a simple example to change the color of the
228 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
230 \override NoteHead #'color = #red
232 \override NoteHead #'color = #green
236 @strong{\revert command}
238 @cindex revert command
243 Once overridden, the property retains its new value until it is
244 overridden again or a @code{\revert} command is encountered.
245 The @code{\revert} command has the following syntax and causes
246 the value of the property to revert to its original default
247 value; note, not its previous value if several @code{\override}
248 commands have been issued.
251 \revert @var{Context}.@var{LayoutObject} #'@var{layout-property}
254 Again, just like @var{Context} in the @code{\override} command,
255 @var{Context} is often not needed. It will be omitted
256 in many of the following examples. Here we revert the color
257 of the note head to the default value for the final two notes:
259 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
261 \override NoteHead #'color = #red
263 \override NoteHead #'color = #green
265 \revert NoteHead #'color
269 @strong{\once prefix}
274 Both the @code{\override} and the @code{\set} commands may be
275 prefixed by @code{\once}. This causes the following
276 @code{\override} or @code{\set} command to be effective only
277 during the current musical moment before the property reverts
278 back to its default value. Using the same example, we can
279 change the color of a single note like this:
281 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
283 \once \override NoteHead #'color = #red
285 \once \override NoteHead #'color = #green
289 @strong{\overrideProperty command}
291 @cindex overrideProperty command
293 @funindex \overrideProperty
294 @funindex overrideProperty
296 There is another form of the override command,
297 @code{\overrideProperty}, which is occasionally required.
298 We mention it here for completeness, but for details see
299 @ruser{Difficult tweaks}.
300 @c Maybe explain in a later iteration -td
302 @strong{\tweak command}
304 @cindex tweak command
309 The final tweaking command which is available is @code{\tweak}.
310 This should be used to change the properties of objects which
311 occur at the same musical moment, such as the notes within a
312 chord. Using @code{\override} would affect all the notes
313 within a chord, whereas @code{\tweak} affects just the following
314 item in the input stream.
316 Here's an example. Suppose we wish to change the size of the
317 middle note head (the E) in a C major chord. Let's first see what
318 @code{\once \override} would do:
320 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
322 \once \override NoteHead #'font-size = #-3
327 We see the override affects @emph{all} the note heads in the chord.
328 This is because all the notes of a chord occur at the same
329 @emph{musical moment}, and the action of @code{\once} is to
330 apply the override to all layout objects of the type specified
331 which occur at the same musical moment as the @code{\override}
334 The @code{\tweak} command operates in a different way. It acts
335 on the immediately following item in the input stream. However,
336 it is effective only on objects which are created directly from
337 the input stream, essentially note heads and articulations;
338 objects such as stems and accidentals are created later and
339 cannot be tweaked in this way. Furthermore, when it is applied
340 to note heads these @emph{must} be within a chord, i.e., within
341 single angle brackets, so to tweak a single note the @code{\tweak}
342 command must be placed inside single angle brackets with the
345 So to return to our example, the size of the middle note of
346 a chord would be changed in this way:
348 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
350 <c \tweak #'font-size #-3 e g>4
353 Note that the syntax of @code{\tweak} is different from that
354 of the @code{\override} command. Neither the context nor the
355 layout object should be specified; in fact, it would generate
356 an error to do so. These are both implied by the following
357 item in the input stream. So the general syntax of the
358 @code{\tweak} command is simply
361 \tweak #'@var{layout-property} = #@var{value}
364 A @code{\tweak} command can also be used to modify just one in
365 a series of articulations, as shown here:
367 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
369 -\tweak #'color #red ^Red
370 -\tweak #'color #green _Green
374 Note that the @code{\tweak} command must be preceded by an
375 articulation mark as if it were an articulation itself.
377 @cindex tuplets, nested
378 @cindex triplets, nested
379 @cindex bracket, tuplet
380 @cindex tuplet bracket
381 @cindex triplet bracket
383 @funindex TupletBracket
385 The @code{\tweak} command must also be used to change the
386 appearance of one of a set of nested tuplets which begin at the
387 same musical moment. In the following example, the long tuplet
388 bracket and the first of the three short brackets begin at the
389 same musical moment, so any @code{\override} command would apply
390 to both of them. In the example, @code{\tweak} is used to
391 distinguish between them. The first @code{\tweak} command
392 specifies that the long tuplet bracket is to be placed above the
393 notes and the second one specifies that the tuplet number is to be
394 printed in red on the first short tuplet bracket.
396 @lilypond[quote,ragged-right,verbatim,fragment,relative=2]
397 \tweak #'direction #up
400 \times 2/3 { c8[ c8 c8] }
401 \times 2/3 { c8[ c8 c8] }
402 \times 2/3 { c8[ c8 c8] }
406 If nested tuplets do not begin at the same moment, their
407 appearance may be modified in the usual way with
408 @code{\override} commands:
410 @c NOTE Tuplet brackets collide if notes are high on staff
412 @lilypond[quote,ragged-right,verbatim,fragment,relative=1]
413 \times 2/3 { c8[ c c]}
414 \once \override TupletNumber
415 #'text = #tuplet-number::calc-fraction-text
419 \once \override TupletNumber #'transparent = ##t
420 \times 2/3 { c8[ c c] }
421 \times 2/3 { c8[ c c]}
428 @ruser{The tweak command}.
431 @node The Internals Reference manual
432 @section The Internals Reference manual
434 @cindex Internals Reference
437 * Properties of layout objects::
438 * Properties found in interfaces::
439 * Types of properties::
442 @node Properties of layout objects
443 @subsection Properties of layout objects
445 @cindex properties of layout objects
446 @cindex properties of grobs
447 @cindex grobs, properties of
448 @cindex layout objects, properties of
449 @cindex Internals Reference manual
451 Suppose you have a slur in a score which, to your mind,
452 appears too thin and you'd like to draw it a little heavier.
453 How do you go about doing this? You know from the statements
454 earlier about the flexibility of LilyPond that such a thing
455 should be possible, and you would probably guess that an
456 @code{\override} command would be needed. But is there a
457 heaviness property for a slur, and if there is, how might it
458 be modified? This is where the Internals Reference manual
459 comes in. It contains all the information you might need to
460 construct this and all other @code{\override} commands.
462 Before we look at the Internals Reference a word of warning.
463 This is a @strong{reference} document, which means there is
464 little or no explanation contained within it: its purpose is
465 to present information precisely and concisely. This
466 means it might look daunting at first sight. Don't worry!
467 The guidance and explanation presented here will enable you
468 to extract the information from the Internals Reference for
469 yourself with just a little practice.
471 @cindex override example
472 @cindex Internals Reference, example of using
474 Let's use a concrete example with a simple fragment of real
477 @lilypond[quote,verbatim,relative=2]
482 g[( e]) e d[( f]) a |
486 The man who feels love's sweet e -- mo -- tion
491 Suppose now that we decide we would like the slurs to be a
492 little heavier. Is this possible? The slur is certainly a
493 layout object, so the question is, @q{Is there a property
494 belonging to a slur which controls the heaviness?} To answer
495 this we must look in the Internals Reference, or IR for short.
497 The IR for the version of LilyPond you are using may be found
498 on the LilyPond website at @uref{http://lilypond.org}. Go to the
499 documentation page and click on the Internals Reference link.
500 For learning purposes you should use the standard HTML version,
501 not the @q{one big page} or the PDF. For the next few
502 paragraphs to make sense you will need to actually do this
505 Under the heading @strong{Top} you will see five links. Select
506 the link to the @emph{Backend}, which is where information about
507 layout objects is to be found. There, under the heading
508 @strong{Backend}, select the link to @emph{All layout objects}.
509 The page that appears lists all the layout objects used in your
510 version of LilyPond, in alphabetic order. Select the link to
511 Slur, and the properties of Slurs are listed.
513 An alternative way of finding this page is from the Notation
514 Reference. On one of the pages that deals with slurs you may find a
515 link to the Internals Reference. This link will take you directly to
516 this page, but if you have an idea about the name of the layout object
517 to be tweaked, it is easier to go straight to the IR and search there.
519 This Slur page in the IR tells us first that Slur objects are created
520 by the Slur_engraver. Then it lists the standard settings. Note
521 these are @strong{not} in alphabetic order. Browse down them looking
522 for a property that might control the heaviness of slurs, and you
526 @code{thickness} (number)
528 Line thickness, generally measured in @code{line-thickness}
531 This looks a good bet to change the heaviness. It tells us that
532 the value of @code{thickness} is a simple @emph{number},
533 that the default value is 1.2, and that the units are
534 in another property called @code{line-thickness}.
536 As we said earlier, there are few to no explanations in the IR,
537 but we already have enough information to try changing the
538 slur thickness. We see that the name of the layout object
539 is @code{Slur}, that the name of the property to change is
540 @code{thickness} and that the new value should be a number
541 somewhat larger than 1.2 if we are to make slurs thicker.
543 We can now construct the @code{\override} command by simply
544 substituting the values we have found for the names, omitting
545 the context. Let's use a very large value for the thickness
546 at first, so we can be sure the command is working. We get:
549 \override Slur #'thickness = #5.0
552 Don't forget the @code{#'} preceding the
553 property name and and @code{#} preceding the new value!
555 The final question is, @q{Where should this command be
556 placed?} While you are unsure and learning, the best
557 answer is, @q{Within the music, before the first slur and
558 close to it.} Let's do that:
560 @lilypond[quote,verbatim,relative=2]
564 % Increase thickness of all following slurs from 1.2 to 5.0
565 \override Slur #'thickness = #5.0
567 g[( e]) e d[( f]) a |
571 The man who feels love's sweet e -- mo -- tion
577 and we see that the slur is indeed heavier.
579 So this is the basic way of constructing @code{\override}
580 commands. There are a few more complications that we
581 shall meet in later sections, but you now know all the
582 essentials required to make up your own -- but you will
583 still need some practice. This is provided in the examples
586 @subheading Finding the context
588 @cindex context, finding
589 @cindex context, identifying correct
591 But first, what if we had needed to specify the Context?
592 What should it be? We could guess that slurs are in
593 the Voice context, as they are clearly closely associated
594 with individual lines of music, but can we be sure? To
595 find out, go back to the top of the IR page describing the
596 Slur, where it says @q{Slur objects are created by: Slur
597 engraver}. So slurs will be created in whichever context
598 the @code{Slur_engraver} is in. Follow the link to the
599 @code{Slur_engraver} page. At the very bottom it tells
600 us that @code{Slur_engraver} is part of five Voice contexts,
601 including the standard voice context, @code{Voice}, so our
602 guess was correct. And because @code{Voice} is one of the
603 lowest level contexts which is implied unambiguously by
604 the fact that we are entering notes, we can omit it in this
607 @subheading Overriding once only
609 @cindex overriding once only
610 @cindex once override
615 As you can see, @emph{all} the slurs are thicker in the final example
616 above. But what if we wanted just the first slur to be thicker? This
617 is achieved with the @code{\once} command. Placed immediately before
618 the @code{\override} command it causes it to change only the slur
619 which begins on the @strong{immediately following} note. If the
620 immediately following note does not begin a slur the command has no
621 effect at all -- it is not remembered until a slur is encountered, it
622 is simply discarded. So the command with @code{\once} must be
623 repositioned as follows:
625 @lilypond[quote,verbatim,relative=2]
630 % Increase thickness of immediately following slur only
631 \once \override Slur #'thickness = #5.0
633 g[( e]) e d[( f]) a |
637 The man who feels love's sweet e -- mo -- tion
643 Now only the first slur is made heavier.
645 The @code{\once} command can also be used before the @code{\set}
648 @subheading Reverting
651 @cindex default properties, reverting to
656 Finally, what if we wanted just the first two slurs to be
657 heavier? Well, we could use two commands, each preceded by
658 @code{\once} placed immediately before each of the notes where
661 @lilypond[quote,verbatim,relative=2]
666 % Increase thickness of immediately following slur only
667 \once \override Slur #'thickness = #5.0
669 % Increase thickness of immediately following slur only
670 \once \override Slur #'thickness = #5.0
671 g[( e]) e d[( f]) a |
675 The man who feels love's sweet e -- mo -- tion
681 or we could omit the @code{\once} command and use the @code{\revert}
682 command to return the @code{thickness} property to its default value
683 after the second slur:
685 @lilypond[quote,verbatim,relative=2]
690 % Increase thickness of all following slurs from 1.2 to 5.0
691 \override Slur #'thickness = #5.0
694 % Revert thickness of all following slurs to default of 1.2
695 \revert Slur #'thickness
700 The man who feels love's sweet e -- mo -- tion
706 The @code{\revert} command can be used to return any property
707 changed with @code{\override} back to its default value.
708 You may use whichever method best suits what you want to do.
710 That concludes our introduction to the IR, and the basic
711 method of tweaking. Several examples follow in the later
712 sections of this Chapter, partly to introduce you to some of the
713 additional features of the IR, and partly to give you more
714 practice in extracting information from it. These examples will
715 contain progressively fewer words of guidance and explanation.
718 @node Properties found in interfaces
719 @subsection Properties found in interfaces
722 @cindex interface properties
723 @cindex properties in interfaces
725 Suppose now that we wish to print the lyrics in italics. What form of
726 @code{\override} command do we need to do this? We first look in the
727 IR page listing @q{All layout objects}, as before, and look for an
728 object that might control lyrics. We find @code{LyricText}, which
729 looks right. Clicking on this shows the settable properties for lyric
730 text. These include the @code{font-series} and @code{font-size}, but
731 nothing that might give an italic shape. This is because the shape
732 property is one that is common to all font objects, so, rather than
733 including it in every layout object, it is grouped together with other
734 similar common properties and placed in an @strong{Interface}, the
735 @code{font-interface}.
737 So now we need to learn how to find the properties of interfaces,
738 and to discover what objects use these interface properties.
740 Look again at the IR page which describes LyricText. At the bottom of
741 the page is a list of clickable interfaces which LyricText supports.
742 The list has several items, including @code{font-interface}. Clicking
743 on this brings up the properties associated with this interface, which
744 are also properties of all the objects which support it, including
747 Now we see all the user-settable properties which control fonts,
748 including @code{font-shape(symbol)}, where @code{symbol} can be
749 set to @code{upright}, @code{italics} or @code{caps}.
751 You will notice that @code{font-series} and @code{font-size} are also
752 listed there. This immediately raises the question: Why are the
753 common font properties @code{font-series} and @code{font-size} listed
754 under @code{LyricText} as well as under the interface
755 @code{font-interface} but @code{font-shape} is not? The answer is
756 that @code{font-series} and @code{font-size} are changed from their
757 global default values when a @code{LyricText} object is created, but
758 @code{font-shape} is not. The entries in @code{LyricText} then tell
759 you the values for those two properties which apply to
760 @code{LyricText}. Other objects which support @code{font-interface}
761 will set these properties differently when they are created.
763 Let's see if we can now construct the @code{\override} command
764 to change the lyrics to italics. The object is @code{LyricText},
765 the property is @code{font-shape} and the value is
766 @code{italic}. As before, we'll omit the context.
768 As an aside, although it is an important one, note that because the
769 values of @code{font-shape} are symbols they must be introduced with a
770 single apostrophe, @code{'}. That is why apostrophes are needed
771 before @code{thickness} in the earlier example and @code{font-shape}.
772 These are both symbols too. Symbols are then read internally by
773 LilyPond. Some of them are the names of properties, like
774 @code{thickness} or @code{font-shape}, others are used as values that
775 can be given to properties, like @code{italic}. Note the distinction
776 from arbitrary text strings, which would appear as @code{"a text
777 string"}; for more details about symbols and strings, see @ref{Scheme
780 Ok, so the @code{\override} command we need to print the lyrics
784 \override LyricText #'font-shape = #'italic
788 and this should be placed just in front of and close to the
789 lyrics which it should affect, like this:
791 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
796 g[( e]) e d[( f]) a |
800 \override LyricText #'font-shape = #'italic
801 The man who feels love's sweet e -- mo -- tion
807 and the lyrics are all printed in italics.
809 @subheading Specifying the context in lyric mode
811 @cindex context, specifying in lyric mode
812 @cindex lyric mode, specifying context
814 In the case of lyrics, if you try specifying the context in the
815 format given earlier the command will fail. A syllable
816 entered in lyricmode is terminated by either a space,
817 a newline or a digit. All other characters are included
818 as part of the syllable. For this reason a space or newline
819 must appear before the terminating @code{@}} to prevent it being
820 included as part of the final syllable. Similarly,
821 spaces must be inserted before and after the
822 period or dot, @q{.}, separating the context name from the
823 object name, as otherwise the two names are run together and
824 the interpreter cannot recognize them. So the command should be:
827 \override Lyrics . LyricText #'font-shape = #'italic
830 @warning{In lyrics always leave whitespace between the final
831 syllable and the terminating brace.}
833 @warning{In overrides in lyrics always place spaces around
834 the dot between the context name and the object name.}
838 Learning Manual: @ref{Scheme tutorial}.
841 @node Types of properties
842 @subsection Types of properties
844 @cindex property types
846 So far we have seen two types of property: @code{number} and
847 @code{symbol}. To be valid, the value given to a property
848 must be of the correct type and obey the rules for that type.
849 The type of property is always shown in brackets after the
850 property name in the IR. Here is a list of the types you may
851 need, together with the rules for that type, and some examples.
852 You must always add a hash symbol, @code{#}, of course,
853 to the front of these values when they are entered in the
854 @code{\override} command.
856 @multitable @columnfractions .2 .45 .35
857 @headitem Property type
861 @tab Either True or False, represented by #t or #f
862 @tab @code{#t}, @code{#f}
863 @item Dimension (in staff space)
864 @tab A positive decimal number (in units of staff space)
865 @tab @code{2.5}, @code{0.34}
867 @tab A valid direction constant or its numerical equivalent (decimal
868 values between -1 and 1 are allowed)
869 @tab @code{LEFT}, @code{CENTER}, @code{UP},
872 @tab A positive whole number
873 @tab @code{3}, @code{1}
875 @tab A set of values separated by spaces, enclosed in parentheses
876 and preceded by an apostrophe
877 @tab @code{'(left-edge staff-bar)}, @code{'(1)},
878 @code{'(1.0 0.25 0.5)}
880 @tab Any valid markup
881 @tab @code{\markup @{ \italic "cresc." @}}
883 @tab A fraction of a whole note constructed with the
885 @tab @code{(ly:make-moment 1 4)},
886 @code{(ly:make-moment 3 8)}
888 @tab Any positive or negative decimal value
889 @tab @code{3.5}, @code{-2.45}
890 @item Pair (of numbers)
891 @tab Two numbers separated by a @q{space . space} and enclosed
892 in brackets preceded by an apostrophe
893 @tab @code{'(2 . 3.5)}, @code{'(0.1 . -3.2)}
895 @tab Any of the set of permitted symbols for that property,
896 preceded by an apostrophe
897 @tab @code{'italic}, @code{'inside}
899 @tab A procedure, or @code{#f} to cause no action
900 @tab @code{bend::print}, @code{ly:text-interface::print},
903 @tab A list of three items enclosed in parentheses and preceded
904 by apostrophe-hash, @code{'#}.
905 @tab @code{'#(#t #t #f)}
910 Learning Manual: @ref{Scheme tutorial}.
913 @node Appearance of objects
914 @section Appearance of objects
916 Let us now put what we have learned into practice with a few
917 examples which show how tweaks may be used to change the
918 appearance of the printed music.
921 * Visibility and color of objects::
923 * Length and thickness of objects::
926 @node Visibility and color of objects
927 @subsection Visibility and color of objects
929 In the educational use of music we might wish to print a score
930 with certain elements omitted as an exercise for the student,
931 who is required to supply them. As a simple example,
932 let us suppose the exercise is to supply the missing bar lines
933 in a piece of music. But the bar lines are normally inserted
934 automatically. How do we prevent them printing?
936 Before we tackle this, let us remember that object properties are
937 grouped in what are called @emph{interfaces} -- see @ref{Properties
938 found in interfaces}. This is simply to group together those
939 properties that may be used together to tweak a graphical object -- if
940 one of them is allowed for an object, so are the others. Some objects
941 then use the properties in some interfaces, others use them from other
942 interfaces. The interfaces which contain the properties used by a
943 particular grob are listed in the IR at the bottom of the page
944 describing that grob, and those properties may be viewed by looking at
947 We explained how to find information about grobs in @ref{Properties of
948 layout objects}. Using the same approach, we go to the IR to find the
949 layout object which prints bar lines. Going via @emph{Backend} and
950 @emph{All layout objects} we find there is a layout object called
951 @code{BarLine}. Its properties include two that control its
952 visibility: @code{break-visibility} and @code{stencil}. Barline also
953 supports a number of interfaces, including the @code{grob-interface},
954 where we find the @code{transparent} and the @code{color} properties.
955 All of these can affect the visibility of bar lines (and, of course,
956 by extension, many other layout objects too.) Let's consider each of
961 @cindex stencil property
963 This property controls the appearance of the bar lines by specifying
964 the symbol (glyph) which should be printed. In common
965 with many other properties, it can be set to print nothing by
966 setting its value to @code{#f}. Let's try it, as before, omitting
967 the implied Context, @code{Voice}:
969 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
972 \override BarLine #'stencil = ##f
979 The bar lines are still printed. What is wrong? Go back to the IR
980 and look again at the page giving the properties of BarLine. At the
981 top of the page it says @qq{Barline objects are created by:
982 Bar_engraver}. Go to the @code{Bar_engraver} page. At the bottom it
983 gives a list of Contexts in which the bar engraver operates. All of
984 them are of the type @code{Staff}, so the reason the @code{\override}
985 command failed to work as expected is because @code{Barline} is not in
986 the default @code{Voice} context. If the context is specified
987 wrongly, the command simply does not work. No error message is
988 produced, and nothing is logged in the log file. Let's try correcting
989 it by adding the correct context:
991 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
994 \override Staff.BarLine #'stencil = ##f
1001 Now the bar lines have vanished.
1003 @subheading break-visibility
1005 @cindex break-visibility property
1007 We see from the @code{BarLine} properties in the IR that the
1008 @code{break-visibility} property requires a vector of three booleans.
1009 These control respectively whether bar lines are printed at the end of
1010 a line, in the middle of lines, and at the beginning of lines. For
1011 our example we want all bar lines to be suppressed, so the value we
1012 need is @code{'#(#f #f #f)}. Let's try that, remembering to include
1013 the @code{Staff} context. Note also that in writing this value we
1014 have @code{#'#} before the opening bracket. The @code{'#} is required
1015 as part of the value to introduce a vector, and the first @code{#} is
1016 required, as always, to precede the value itself in the
1017 @code{\override} command.
1019 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1022 \override Staff.BarLine #'break-visibility = #'#(#f #f #f)
1024 g, a16 b8 c d4 e16 |
1029 And we see this too removes all the bar lines.
1031 @subheading transparent
1033 @cindex transparent property
1034 @cindex transparency
1036 We see from the properties specified in the @code{grob-interface} page
1037 in the IR that the @code{transparent} property is a boolean. This
1038 should be set to @code{#t} to make the grob transparent. In this next
1039 example let us make the time signature invisible rather than the bar
1040 lines. To do this we need to find the grob name for the time
1041 signature. Back to the @q{All layout objects} page in the IR to find
1042 the properties of the @code{TimeSignature} layout object. This is
1043 produced by the @code{Time_signature_engraver} which you can check
1044 also lives in the @code{Staff} context and also supports the
1045 @code{grob-interface}. So the command to make the time signature
1048 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1051 \override Staff.TimeSignature #'transparent = ##t
1053 g, a16 b8 c d4 e16 |
1059 The time signature is gone, but this command leaves a gap where
1060 the time signature should be. Maybe this is what is wanted for
1061 an exercise for the student to fill it in, but in other
1062 circumstances a gap might be undesirable. To remove it, the
1063 stencil for the time signature should be set to @code{#f}
1066 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1069 \override Staff.TimeSignature #'stencil = ##f
1071 g, a16 b8 c d4 e16 |
1077 and the difference is obvious: setting the stencil to @code{#f}
1078 removes the object entirely; making the object @code{transparent}
1079 leaves it where it is, but makes it invisible.
1083 @cindex color property
1085 Finally let us try making the bar lines invisible by coloring
1086 them white. (There is a difficulty with this in that the
1087 white bar line may or may not blank out the staff lines where
1088 they cross. You may see in some of the examples below that this
1089 happens unpredictably. The details of why this is so and how to
1090 control it are covered in @ruser{Painting objects white}. But at
1091 the moment we are learning about color, so please just accept this
1092 limitation for now.)
1094 The @code{grob-interface} specifies that the
1095 color property value is a list, but there is no
1096 explanation of what that list should be. The list it
1097 requires is actually a list of values in internal units,
1098 but, to avoid having to know what these are, several ways
1099 are provided to specify colors. The first way is to use one
1100 of the @q{normal} colors listed in the first table in
1101 @ruser{List of colors}. To set the bar lines to white
1104 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1107 \override Staff.BarLine #'color = #white
1109 g, a16 b8 c d4 e16 |
1115 and again, we see the bar lines are not visible. Note that
1116 @emph{white} is not preceded by an apostrophe -- it is not
1117 a symbol, but a @emph{function}. When called, it provides
1118 the list of internal values required to set the color to
1119 white. The other colors in the normal list are functions
1120 too. To convince yourself this is working you might like
1121 to change the color to one of the other functions in the
1129 The second way of changing the color is to use the list of
1130 X11 color names in the second list in @ruser{List of colors}.
1131 However, these must be preceded by another function, which
1132 converts X11 color names into the list of internal values,
1133 @code{x11-color}, like this:
1135 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1138 \override Staff.BarLine #'color = #(x11-color 'white)
1140 g, a16 b8 c d4 e16 |
1146 Note that in this case the function @code{x11-color} takes
1147 a symbol as an argument, so the symbol must be preceded by
1148 an apostrophe and the two enclosed in brackets.
1155 There is yet a third function, one which converts RGB values into
1156 internal colors -- the @code{rgb-color} function. This takes
1157 three arguments giving the intensities of the red, green and
1158 blue colors. These take values in the range 0 to 1. So to
1159 set the color to red the value should be @code{(rgb-color 1 0 0)}
1160 and to white it should be @code{(rgb-color 1 1 1)}:
1162 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1165 \override Staff.BarLine #'color = #(rgb-color 1 1 1)
1167 g, a16 b8 c d4 e16 |
1172 Finally, there is also a grey scale available as part of the
1173 X11 set of colors. These range from black, @code{'grey0'},
1174 to white, @code{'grey100}, in steps of 1. Let's illustrate
1175 this by setting all the layout objects in our example to
1176 various shades of grey:
1178 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1181 \override Staff.StaffSymbol #'color = #(x11-color 'grey30)
1182 \override Staff.TimeSignature #'color = #(x11-color 'grey60)
1183 \override Staff.Clef #'color = #(x11-color 'grey60)
1184 \override Voice.NoteHead #'color = #(x11-color 'grey85)
1185 \override Voice.Stem #'color = #(x11-color 'grey85)
1186 \override Staff.BarLine #'color = #(x11-color 'grey10)
1188 g, a16 b8 c d4 e16 |
1194 Note the contexts associated with each of the layout objects.
1195 It is important to get these right, or the commands will not
1196 work! Remember, the context is the one in which the appropriate
1197 engraver is placed. The default context for engravers can be
1198 found by starting from the layout object, going from there to
1199 the engraver which produces it, and on the engraver page in the
1200 IR it tells you in which context the engraver will normally be
1204 @node Size of objects
1205 @subsection Size of objects
1207 @cindex changing size of objects
1208 @cindex size of objects
1209 @cindex objects, size of
1210 @cindex objects, changing size of
1212 Let us begin by looking again at the earlier example
1213 see @ref{Nesting music expressions}) which showed
1214 how to introduce a new temporary staff, as in an @rglos{ossia}.
1216 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1217 \new Staff ="main" {
1224 alignAboveContext = "main" }
1232 Ossia are normally written without clef and time signature, and
1233 are usually printed slightly smaller than the main staff. We
1234 already know now how to remove the clef and time signature --
1235 we simply set the stencil of each to @code{#f}, as follows:
1237 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1238 \new Staff ="main" {
1245 alignAboveContext = "main"
1248 \override Staff.Clef #'stencil = ##f
1249 \override Staff.TimeSignature #'stencil = ##f
1259 where the extra pair of braces after the @code{\with} clause are
1260 required to ensure the enclosed overrides and music are applied
1263 But what is the difference between modifying the staff context by
1264 using @code{\with} and modifying the stencils of the clef and the
1265 time signature with \override? The main difference is that
1266 changes made in a @code{\with} clause are made at the time the
1267 context is created, and remain in force as the @strong{default}
1268 values for the duration of that context, whereas
1269 @code{\set} or @code{\override} commands embedded in the
1270 music are dynamic -- they make changes synchronized with
1271 a particular point in the music. If changes are unset or
1272 reverted using @code{\unset} or @code{\revert} they return to
1273 their default values, which will be the ones set in the
1274 @code{\with} clause, or if none have been set there, the normal
1277 Some context properties can be modified only in @code{\with} clauses.
1278 These are those properties which cannot sensibly be changed after the
1279 context has been created. @code{alignAboveContext} and its partner,
1280 @code{alignBelowContext}, are two such properties -- once the staff
1281 has been created its alignment is decided and it would make no sense
1282 to try to change it later.
1284 The default values of layout object properties can also be set
1285 in @code{\with} clauses. Simply use the normal @code{\override}
1286 command leaving out the context name, since this is unambiguously
1287 defined as the context which the @code{\with} clause is modifying.
1288 If fact, an error will be generated if a context is specified
1291 So we could replace the example above with
1293 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1294 \new Staff ="main" {
1301 alignAboveContext = "main"
1302 % Don't print clefs in this staff
1303 \override Clef #'stencil = ##f
1304 % Don't print time signatures in this staff
1305 \override TimeSignature #'stencil = ##f
1314 Finally we come to changing the size of layout objects.
1316 Some layout objects are created as glyphs selected from a typeface
1317 font. These include note heads, accidentals, markup, clefs, time
1318 signatures, dynamics and lyrics. Their size is changed by modifying
1319 the @code{font-size} property, as we shall shortly see. Other layout
1320 objects such as slurs and ties -- in general, spanner objects -- are
1321 drawn individually, so there is no @code{font-size} associated with
1322 them. These objects generally derive their size from the objects to
1323 which they are attached, so usually there is no need to change their
1324 size manually. Still other properties such as the length of stems and
1325 bar lines, thickness of beams and other lines, and the separation of
1326 staff lines all need to be modified in special ways.
1328 Returning to the ossia example, let us first change the font-size.
1329 We can do this in two ways. We can either change the size of the
1330 fonts of each object type, like @code{NoteHead}s with commands
1334 \override NoteHead #'font-size = #-2
1337 or we can change the size of all fonts by setting a special
1338 property, @code{fontSize}, using @code{\set}, or by including
1339 it in a @code{\with} clause (but without the @code{\set}).
1345 Both of these statements would cause the font size to be reduced
1346 by 2 steps from its previous value, where each
1347 step reduces or increases the size by approximately 12%.
1349 Let's try it in our ossia example:
1351 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1352 \new Staff ="main" {
1359 alignAboveContext = "main"
1360 \override Clef #'stencil = ##f
1361 \override TimeSignature #'stencil = ##f
1362 % Reduce all font sizes by ~24%
1372 This is still not quite right. The note heads and flags are
1373 smaller, but the stems are too long in proportion and the
1374 staff lines are spaced too widely apart. These need to be
1375 scaled down in proportion to the font reduction. The next
1376 sub-section discusses how this is done.
1378 @node Length and thickness of objects
1379 @subsection Length and thickness of objects
1385 @cindex size, changing
1386 @cindex stem length, changing
1387 @cindex staff line spacing, changing
1389 Distances and lengths in LilyPond are generally measured in
1390 staff-spaces, the distance between adjacent lines in the staff,
1391 (or occasionally half staff spaces) while most @code{thickness}
1392 properties are measured in units of an internal property called
1393 @code{line-thickness.} For example, by default, the lines of
1394 hairpins are given a thickness of 1 unit of @code{line-thickness},
1395 while the @code{thickness} of a note stem is 1.3. Note, though,
1396 that some thickness properties are different; for example, the
1397 thickness of beams is measured in staff-spaces.
1399 So how are lengths to be scaled in proportion to the font size?
1400 This can be done with the help of a special function called
1401 @code{magstep} provided for exactly this purpose. It takes
1402 one argument, the change in font size (#-2 in the example above)
1403 and returns a scaling factor suitable for reducing other
1404 objects in proportion. It is used like this:
1406 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1407 \new Staff ="main" {
1414 alignAboveContext = "main"
1415 \override Clef #'stencil = ##f
1416 \override TimeSignature #'stencil = ##f
1418 % Reduce stem length and line spacing to match
1419 \override StaffSymbol #'staff-space = #(magstep -2)
1429 Since the length of stems and many other length-related properties are
1430 always calculated relative to the value of the @code{staff-space}
1431 property these are automatically scaled down in length too. Note that
1432 this affects only the vertical scale of the ossia -- the horizontal
1433 scale is determined by the layout of the main music in order to remain
1434 synchronized with it, so it is not affected by any of these changes in
1435 size. Of course, if the scale of all the main music were changed in
1436 this way then the horizontal spacing would be affected. This is
1437 discussed later in the layout section.
1439 This, then, completes the creation of an ossia. The sizes and
1440 lengths of all other objects may be modified in analogous ways.
1442 For small changes in scale, as in the example above, the
1443 thickness of the various drawn lines such as bar lines,
1444 beams, hairpins, slurs, etc does not usually require global
1445 adjustment. If the thickness of any particular layout object
1446 needs to be adjusted this can be best achieved by overriding its
1447 @code{thickness} property. An example of changing the thickness
1448 of slurs was shown above in @ref{Properties of layout objects}.
1449 The thickness of all drawn objects (i.e., those not produced
1450 from a font) may be changed in the same way.
1453 @node Placement of objects
1454 @section Placement of objects
1457 * Automatic behavior::
1458 * Within-staff objects::
1459 * Outside-staff objects::
1463 @node Automatic behavior
1464 @subsection Automatic behavior
1466 @cindex within-staff objects
1467 @cindex outside-staff objects
1468 @cindex objects, within-staff
1469 @cindex objects, outside-staff
1471 There are some objects in musical notation that belong to
1472 the staff and there are other objects that should be
1473 placed outside the staff. These are called within-staff
1474 objects and outside-staff objects respectively.
1476 Within-staff objects are those that are located on the staff
1477 -- note heads, stems, accidentals, etc. The positions of
1478 these are usually fixed by the music itself -- they are
1479 vertically positioned on specific lines of the staff or are
1480 tied to other objects that are so positioned. Collisions of
1481 note heads, stems and accidentals in closely set chords are
1482 normally avoided automatically. There are commands and
1483 overrides which can modify this automatic behavior, as we
1486 Objects belonging outside the staff include things such as
1487 rehearsal marks, text and dynamic markings. LilyPond's rule for
1488 the vertical placement of outside-staff objects is to place them
1489 as close to the staff as possible but not so close that they
1490 collide with any other object. LilyPond uses the
1491 @code{outside-staff-priority} property to determine the order in
1492 which the objects should be placed, as follows.
1494 First, LilyPond places all the within-staff objects.
1495 Then it sorts the outside-staff objects according to their
1496 @code{outside-staff-priority}. The outside-staff objects are
1497 taken one by one, beginning with the object with the lowest
1498 @code{outside-staff-priority}, and placed so that they do not
1499 collide with any objects that have already been placed. That is,
1500 if two outside-staff grobs are competing for the same space, the
1501 one with the lower @code{outside-staff-priority} will be placed
1502 closer to the staff. If two objects have the same
1503 @code{outside-staff-priority} the one encountered first will be
1504 placed closer to the staff.
1506 In the following example all the markup texts have the same
1507 priority (since it is not explicitly set). Note that @q{Text3}
1508 is automatically positioned close to the staff again, nestling
1511 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1518 Staves are also positioned, by default, as closely together as
1519 possible (subject to a minimum separation). If notes project
1520 a long way towards an adjacent staff they will force the
1521 staves further apart only if an overlap of the notation
1522 would otherwise occur. The following example demonstrates
1523 this @q{nestling} of the notes on adjacent staves:
1525 @lilypond[quote,ragged-right,verbatim]
1528 \relative c' { c a, }
1531 \relative c'''' { c a, }
1537 @node Within-staff objects
1538 @subsection Within-staff objects
1540 We have already seen how the commands @code{\voiceXXX} affect
1541 the direction of slurs, ties, fingering and
1542 everything else which depends on the direction of the stems.
1543 These commands are essential when writing polyphonic music to
1544 permit interweaving melodic lines to be distinguished.
1545 But occasionally it may be necessary to override this automatic
1546 behavior. This can be done for whole sections of music or even
1547 for an individual note. The property which controls this
1548 behavior is the @code{direction} property of each layout object.
1549 We first explain what this does, and then introduce a number of
1550 ready-made commands which avoid your having to code explicit
1551 overrides for the more common modifications.
1553 Some layout objects like slurs and ties curve, bend or point
1554 either up or down; others like stems and flags also move to
1555 right or left when they point up or down. This is controlled
1556 automatically when @code{direction} is set.
1563 The following example shows in bar 1 the default behavior of stems,
1564 with those on high notes pointing down and those on low notes pointing
1565 up, followed by four notes with all stems forced down, four notes with
1566 all stems forced up, and finally four notes reverted back to the
1569 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1571 \override Stem #'direction = #DOWN
1573 \override Stem #'direction = #UP
1575 \revert Stem #'direction
1579 Here we use the constants @code{DOWN} and @code{UP}.
1580 These have the values @code{-1} and @code{+1} respectively, and
1581 these numerical values may be used instead. The value @code{0}
1582 may also be used in some cases. It is simply treated as meaning
1583 @code{UP} for stems, but for some objects it means @q{center}.
1584 There is a constant, @code{CENTER} which has the value @code{0}.
1586 However, these explicit overrides are not usually used, as there are
1587 simpler equivalent predefined commands available. Here is a table of
1588 the commonest. The meaning of each is stated where it is not obvious.
1590 @multitable @columnfractions .2 .2 .25 .35
1595 @item @code{\arpeggioArrowDown}
1596 @tab @code{\arpeggioArrowUp}
1597 @tab @code{\arpeggioNormal}
1598 @tab Arrow is at bottom, at top, or no arrow
1599 @item @code{\dotsDown}
1601 @tab @code{\dotsNeutral}
1602 @tab Direction of movement to avoid staff lines
1603 @item @code{\dynamicDown}
1604 @tab @code{\dynamicUp}
1605 @tab @code{\dynamicNeutral}
1607 @item @code{\phrasingSlurDown}
1608 @tab @code{\phrasingSlurUp}
1609 @tab @code{\phrasingSlurNeutral}
1610 @tab Note: distinct from slur commands
1611 @item @code{\slurDown}
1613 @tab @code{\slurNeutral}
1615 @item @code{\stemDown}
1617 @tab @code{\stemNeutral}
1619 @item @code{\textSpannerDown}
1620 @tab @code{\textSpannerUp}
1621 @tab @code{\textSpannerNeutral}
1622 @tab Text entered as spanner is below/above staff
1623 @item @code{\tieDown}
1625 @tab @code{\tieNeutral}
1627 @item @code{\tupletDown}
1628 @tab @code{\tupletUp}
1629 @tab @code{\tupletNeutral}
1630 @tab Tuplets are below/above notes
1633 Note that these predefined commands may @strong{not} be
1634 preceded by @code{\once}. If you wish to limit the
1635 effect to a single note you must either use the equivalent
1636 @code{\once \override} command or use the predefined command
1637 followed after the affected note by the corresponding
1638 @code{\xxxNeutral} command.
1640 @subheading Fingering
1642 @cindex fingering, placement
1643 @cindex fingering, chords
1645 The placement of fingering is also affected by the value
1646 of its @code{direction} property, but there are special
1647 commands which allow the fingering of individual notes
1648 of chords to be controlled, with the fingering being placed
1649 above, below, to the left or to the right of each note.
1651 First, here's the effect of @code{direction} on fingering,
1652 the first bar shows the default, then the effect of specifying
1653 @code{DOWN} and @code{UP}:
1655 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1657 \override Fingering #'direction = #DOWN
1659 \override Fingering #'direction = #UP
1663 This is how to control fingering on single notes, but the
1664 @code{direction} property is ignored for chords. Instead, by default,
1665 the fingering is automatically placed both above and below the notes
1666 of a chord, as shown:
1668 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1674 Greater control over the placement of fingering of the
1675 individual notes in a chord is possible by using
1676 the @code{\set fingeringOrientations} command. The format of
1680 @code{\set fingeringOrientations = #'([up] [left/right] [down])}
1684 @code{\set} is used because @code{fingeringOrientations} is a
1685 property of the @code{Voice} context, created and used by the
1686 @code{New_fingering_engraver}.
1688 The property may be set to a list of one to three values.
1689 It controls whether fingerings may be placed above (if
1690 @code{up} appears in the list), below (if @code{down} appears),
1691 to the left (if @code{left} appears, or to the right
1692 (if @code{right} appears). Conversely, if a location is not
1693 listed, no fingering is placed there. LilyPond takes these
1694 constraints and works out the best placement for the fingering
1695 of the notes of the following chords. Note that @code{left} and
1696 @code{right} are mutually exclusive -- fingering may be placed
1697 only on one side or the other, not both.
1699 To control the placement of the fingering of a single note
1700 using this command it is necessary to write it as a single
1701 note chord by placing angle brackets round it.
1703 Here are a few examples:
1705 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1706 \set fingeringOrientations = #'(left)
1708 < c-1 e-2 g-3 b-5 > 4
1709 \set fingeringOrientations = #'(left)
1711 < c-1 e-2 g-3 b-5 > 4
1712 \set fingeringOrientations = #'(up left down)
1714 < c-1 e-2 g-3 b-5 > 4
1715 \set fingeringOrientations = #'(up left)
1717 < c-1 e-2 g-3 b-5 > 4
1718 \set fingeringOrientations = #'(right)
1720 < c-1 e-2 g-3 b-5 > 4
1724 If the fingering seems a little crowded the @code{font-size}
1725 could be reduced. The default value can be seen from the
1726 @code{Fingering} object in the IR to be @code{-5}, so let's
1729 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1730 \override Fingering #'font-size = #-7
1731 \set fingeringOrientations = #'(left)
1733 < c-1 e-2 g-3 b-5 > 4
1734 \set fingeringOrientations = #'(left)
1736 < c-1 e-2 g-3 b-5 > 4
1737 \set fingeringOrientations = #'(up left down)
1739 < c-1 e-2 g-3 b-5 > 4
1740 \set fingeringOrientations = #'(up left)
1742 < c-1 e-2 g-3 b-5 > 4
1743 \set fingeringOrientations = #'(right)
1745 < c-1 e-2 g-3 b-5 > 4
1748 @node Outside-staff objects
1749 @subsection Outside-staff objects
1751 Outside-staff objects are automatically placed to avoid collisions.
1752 Objects with the lower value of the @code{outside-staff-priority}
1753 property are placed nearer to the staff, and other outside-staff
1754 objects are then raised as far as necessary to avoid collisions.
1755 The @code{outside-staff-priority} is defined in the
1756 @code{grob-interface} and so is a property of all layout objects.
1757 By default it is set to @code{#f} for all within-staff objects,
1758 and to a numerical value appropriate to each outside-staff object
1759 when the object is created. The following table shows
1760 the default numerical values for some of the commonest
1761 outside-staff objects which are, by default, placed in the
1762 @code{Staff} or @code{Voice} contexts.
1764 @multitable @columnfractions .3 .3 .3
1765 @headitem Layout Object
1767 @tab Controls position of:
1768 @item @code{MultiMeasureRestText}
1770 @tab Text over full-bar rests
1771 @item @code{TextScript}
1774 @item @code{OttavaBracket}
1776 @tab Ottava brackets
1777 @item @code{TextSpanner}
1780 @item @code{DynamicLineSpanner}
1782 @tab All dynamic markings
1783 @item @code{VoltaBracketSpanner}
1786 @item @code{TrillSpanner}
1788 @tab Spanning trills
1791 Here is an example showing the default placement of some of
1794 @cindex text spanner
1795 @cindex ottava bracket
1797 @funindex \startTextSpan
1798 @funindex startTextSpan
1799 @funindex \stopTextSpan
1800 @funindex stopTextSpan
1803 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1804 % Set details for later Text Spanner
1805 \override TextSpanner #'bound-details #'left #'text
1806 = \markup { \small \bold Slower }
1807 % Place dynamics above staff
1809 % Start Ottava Bracket
1814 % Add Dynamic Line Spanner
1820 c\ff c \stopTextSpan
1821 % Stop Ottava Bracket
1826 This example also shows how to create Text Spanners --
1827 text with extender lines above a section of music. The
1828 spanner extends from the @code{\startTextSpan} command to
1829 the @code{\stopTextSpan} command, and the format of the
1830 text is defined by the @code{\override TextSpanner} command.
1831 For more details see @ruser{Text spanners}.
1833 It also shows how ottava brackets are created.
1835 @cindex tweaking bar number placement
1836 @cindex bar numbers, tweaking placement
1837 @cindex tweaking metronome mark placement
1838 @cindex metronome mark, tweaking placement
1839 @cindex tweaking rehearsal mark placement
1840 @cindex rehearsal marks, tweaking placement
1842 Note that bar numbers, metronome marks and rehearsal marks are not
1843 shown. By default these are created in the @code{Score} context and
1844 their @code{outside-staff-priority} is ignored relative to the layout
1845 objects which are created in the @code{Staff} context. If you wish to
1846 place bar numbers, metronome marks or rehearsal marks in accordance
1847 with the value of their @code{outside-staff-priority} the
1848 @code{Bar_number_engraver}, @code{Metronome_mark_engraver} or
1849 @code{Mark_engraver} respectively should be removed from the
1850 @code{Score} context and placed in the top @code{Staff} context. If
1851 this is done, these marks will be given the following default
1852 @code{outside-staff-priority} values:
1854 @multitable @columnfractions .3 .3
1855 @headitem Layout Object @tab Priority
1856 @item @code{RehearsalMark} @tab @code{1500}
1857 @item @code{MetronomeMark} @tab @code{1000}
1858 @item @code{BarNumber} @tab @code{ 100}
1861 If the default values of @code{outside-staff-priority} do not give you
1862 the placing you want, the priority of any of the objects may be
1863 overridden. Suppose we would like the ottava bracket to be placed
1864 below the text spanner in the example above. All we need to do is to
1865 look up the priority of @code{OttavaBracket} in the IR or in the
1866 tables above, and reduce it to a value lower than that of a
1867 @code{TextSpanner}, remembering that @code{OttavaBracket} is created
1868 in the @code{Staff} context:
1870 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1871 % Set details for later Text Spanner
1872 \override TextSpanner #'bound-details #'left #'text
1873 = \markup { \small \bold Slower }
1874 % Place dynamics above staff
1876 %Place following Ottava Bracket below Text Spanners
1877 \once \override Staff.OttavaBracket #'outside-staff-priority = #340
1878 % Start Ottava Bracket
1883 % Add Dynamic Line Spanner
1889 c\ff c \stopTextSpan
1890 % Stop Ottava Bracket
1895 Changing the @code{outside-staff-priority} can also be used to
1896 control the vertical placement of individual objects, although
1897 the results may not always be desirable. Suppose we would
1898 like @qq{Text3} to be placed above @qq{Text4} in the example
1899 under Automatic behavior, above (see @ref{Automatic behavior}).
1900 All we need to do is to look up the priority of @code{TextScript}
1901 in the IR or in the tables above, and increase the priority of
1902 @qq{Text3} to a higher value:
1904 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1907 \once \override TextScript #'outside-staff-priority = #500
1912 This certainly lifts @qq{Text3} above @qq{Text4} but it also lifts it
1913 above @qq{Text2}, and @qq{Text4} now drops down. Perhaps this is not
1914 so good. What we would really like to do is to position all the
1915 annotation at the same distance above the staff. To do this, we
1916 clearly will need to space the notes out horizontally to make more
1917 room for the text. This is done using the @code{textLengthOn}
1920 @subheading \textLengthOn
1922 @cindex notes, spreading out with text
1924 @funindex \textLengthOn
1925 @funindex textLengthOn
1926 @funindex \textLengthOff
1927 @funindex textLengthOff
1929 By default, text produced by markup takes up no horizontal space
1930 as far as laying out the music is concerned. The @code{\textLengthOn}
1931 command reverses this behavior, causing the notes to be spaced
1932 out as far as is necessary to accommodate the text:
1934 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1935 \textLengthOn % Cause notes to space out to accommodate text
1942 The command to revert to the default behavior is
1943 @code{\textLengthOff}. Remember @code{\once} only works with
1944 @code{\override}, @code{\set}, @code{\revert} or @code{unset},
1945 so cannot be used with @code{\textLengthOn}.
1947 @cindex markup text, allowing collisions
1949 Markup text will also avoid notes which project above the staff.
1950 If this is not desired, the automatic displacement upwards may
1951 be turned off by setting the priority to @code{#f}. Here's an
1952 example to show how markup text interacts with such notes.
1954 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1955 % This markup is short enough to fit without collision
1959 % This is too long to fit, so it is displaced upwards
1963 % Turn off collision avoidance
1964 \once \override TextScript #'outside-staff-priority = ##f
1968 % Turn off collision avoidance
1969 \once \override TextScript #'outside-staff-priority = ##f
1970 \textLengthOn % and turn on textLengthOn
1971 c,,2^"Long Text " % Spaces at end are honored
1976 @subheading Dynamics
1978 @cindex tweaking dynamics placement
1979 @cindex dynamics, tweaking placement
1981 Dynamic markings will normally be positioned beneath the
1982 staff, but may be positioned above with the @code{dynamicUp}
1983 command. They will be positioned vertically relative to the
1984 note to which they are attached, and will float below (or above)
1985 all within-staff objects such as phrasing slurs and bar numbers.
1986 This can give quite acceptable results, as this example
1989 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1994 bes4.~\f\< \( bes4 bes8 des4\ff\> c16 bes\! |
1995 ees,2.~\)\mf ees4 r8 |
1998 However, if the notes and attached dynamics are close
1999 together the automatic placement will avoid collisions
2000 by displacing later dynamic markings further away, but this may
2001 not be the optimum placement, as this rather artificial example
2004 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2010 Should a similar situation arise in @q{real} music, it may be
2011 preferable to space out the notes a little further, so the dynamic
2012 markings can all fit at the same vertical distance from the staff. We
2013 were able to do this for markup text by using the @code{\textLengthOn}
2014 command, but there is no equivalent command for dynamic marks. So we
2015 shall have to work out how to do this using @code{\override} commands.
2017 @subheading Grob sizing
2020 @cindex sizing grobs
2021 @cindex @code{X-offset}
2022 @cindex @code{Y-offset}
2023 @cindex @code{X-extent}
2024 @cindex @code{Y-extent}
2026 First we must learn how grobs are sized. All grobs have a
2027 reference point defined within them which is used to position
2028 them relative to their parent object. This point in the grob
2029 is then positioned at a horizontal distance, @code{X-offset},
2030 and at a vertical distance, @code{Y-offset}, from its parent.
2031 The horizontal extent of the object is given by a pair of
2032 numbers, @code{X-extent}, which say where the left and right
2033 edges are relative to the reference point. The vertical extent
2034 is similarly defined by a pair of numbers, @code{Y-extent}.
2035 These are properties of all grobs which support the
2036 @code{grob-interface}.
2038 @cindex @code{extra-spacing-width}
2040 By default, outside-staff objects are given a width of zero so
2041 that they may overlap in the horizontal direction. This is done
2042 by the trick of adding infinity to the leftmost extent and
2043 minus infinity to the rightmost extent by setting the
2044 @code{extra-spacing-width} to @code{'(+inf.0 . -inf.0)}. So
2045 to ensure they do not overlap in the horizontal direction we
2046 must override this value of @code{extra-spacing-width} to
2047 @code{'(0 . 0)} so the true width shines through. This is
2048 the command to do this for dynamic text:
2051 \override DynamicText #'extra-spacing-width = #'(0 . 0)
2055 Let's see if this works in our previous example:
2057 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2059 \override DynamicText #'extra-spacing-width = #'(0 . 0)
2064 Well, it has certainly stopped the dynamic marks being
2065 displaced, but two problems remain. The marks should be
2066 spaced a little further apart and it would be better
2067 if they were all the same distance from the staff.
2068 We can solve the first problem easily. Instead of making
2069 the @code{extra-spacing-width} zero we could add a little
2070 more to it. The units are the space between two staff
2071 lines, so moving the left edge half a unit to the left and the
2072 right edge half a unit to the right should do it:
2074 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2076 % Extend width by 1 staff space
2077 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
2082 This looks better, but maybe we would prefer the dynamic marks
2083 to be aligned along the same baseline rather than going up and
2084 down with the notes. The property to do this is
2085 @code{staff-padding} which is covered in the following section.
2088 @node Collisions of objects
2089 @section Collisions of objects
2093 * Fixing overlapping notation::
2094 * Real music example::
2097 @node Moving objects
2098 @subsection Moving objects
2100 This may come as a surprise, but LilyPond is not perfect. Some
2101 notation elements can overlap. This is unfortunate, but in fact
2102 rather rare. Usually the need to move objects is for clarity or
2103 aesthetic reasons -- they would look better with a little more
2104 or a little less space around them.
2106 There are three main approaches to resolving overlapping
2107 notation. They should be considered in the following order:
2111 The @strong{direction} of one of the overlapping objects may
2112 be changed using the predefined commands listed above for
2113 within-staff objects (see @ref{Within-staff objects}).
2114 Stems, slurs, beams, ties, dynamics, text and tuplets may be
2115 repositioned easily in this way. The limitation is that you
2116 have a choice of only two positions, and neither may be
2120 The @strong{object properties}, which LilyPond uses
2121 when positioning layout objects, may be modified using
2122 @code{\override}. The advantages
2123 of making changes to this type of property are (a) that some
2124 other objects will be moved automatically if necessary to make
2125 room and (b) the single override can apply to all instances of
2126 the same type of object. Such properties include:
2133 This has already been covered in some detail -- see
2134 @ref{Within-staff objects}.
2137 @code{padding}, @code{left-padding},
2138 @code{right-padding}, @code{staff-padding}
2140 @cindex left-padding property
2141 @cindex padding property
2142 @cindex right-padding property
2143 @cindex staff-padding property
2144 As an object is being positioned the value of its @code{padding}
2145 property specifies the gap that must be left between itself and
2146 the nearest edge of the object against which it is being
2147 positioned. Note that it is the @code{padding} value of the object
2148 @strong{being placed} that is used;
2149 the @code{padding} value of the object which is already placed is
2150 ignored. Gaps specified by @code{padding} can be applied
2151 to all objects which support the @code{side-position-interface}.
2153 Instead of @code{padding}, the placement of groups of accidentals
2154 is controlled by @code{left-padding} and @code{right-padding}.
2155 These properties are to be found in the @code{AccidentalPlacement}
2156 object which, note, lives in the @strong{staff} context. In the
2157 type-setting process the note heads are type-set first and then
2158 the accidentals, if any, are added to the left of the note heads
2159 using the @code{right-padding} property to determine the separation
2160 from the note heads. So only the @code{right-padding} property of the
2161 @code{AccidentalPlacement} object has any effect on the placement
2164 The @code{staff-padding} property is closely related to the
2165 @code{padding} property: @code{padding}
2166 controls the minimum amount of space between any object which
2167 supports the @code{side-position-interface} and the nearest
2168 other object (generally the note or the staff lines);
2169 @code{staff-padding} applies only to those objects which are always
2170 set outside the staff -- it controls the minimum amount of space
2171 that should be inserted between that object and the staff. Note
2172 that @code{staff-padding} has no effect on objects which are
2173 positioned relative to the note rather than the staff, even though
2174 it may be overridden without error for such objects -- it is simply
2177 To discover which padding property is required for the object
2178 you wish to reposition, you
2179 need to return to the IR and look up the object's properties.
2180 Be aware that the padding properties might not be located in the
2181 obvious object, so look in objects that appear to be related.
2183 All padding values are measured in staff spaces. For most
2184 objects, this value is set by default to be around 1.0 or less
2185 (it varies with each object). It may be overridden if a larger
2186 (or smaller) gap is required.
2189 @code{self-alignment-X}
2191 @cindex self-alignment-X property
2192 This property can be used to align the object to the left, to
2193 the right, or to center it with respect to the parent object's
2194 reference point. It may be used with all objects which support
2195 the @code{self-alignment-interface}. In general these are objects
2196 that contain text. The values are @code{LEFT}, @code{RIGHT}
2197 or @code{CENTER}. Alternatively, a numerical value between
2198 @code{-1} and @code{+1} may be specified, where @code{-1} is
2199 left-aligned, @code{+1} is right-aligned, and numbers in between
2200 move the text progressively from left-aligned to right-aligned.
2201 Numerical values greater than @code{1} may be specified to move
2202 the text even further to the left, or less than @code{-1} to
2203 move the text even further to the right. A change of @code{1}
2204 in the value corresponds to a movement of half the text's length.
2207 @code{extra-spacing-width}
2209 @cindex extra-spacing-width property
2210 This property is available for all objects which support the
2211 @code{item-interface}. It takes two numbers, the first is added
2212 to the leftmost extent and the second is added to the rightmost
2213 extent. Negative numbers move the edge to the left, positive to
2214 the right, so to widen an object the first number must be negative,
2215 the second positive. Note that not all objects honor both
2216 numbers. For example, the @code{Accidental} object only takes
2217 notice of the first (left edge) number.
2220 @code{staff-position}
2222 @cindex staff-position property
2223 @code{staff-position} is a property of the
2224 @code{staff-symbol-referencer-interface}, which is supported by
2225 objects which are positioned relative to the staff. It specifies
2226 the vertical position of the object relative to the center line
2227 of the staff in half staff-spaces. It is useful in resolving
2228 collisions between layout objects like multi-measure rests, ties
2229 and notes in different voices.
2234 @cindex force-hshift property
2236 Closely spaced notes in a chord, or notes occurring at the same
2237 time in different voices, are arranged in two, occasionally more,
2238 columns to prevent the note heads overlapping. These are called
2239 note columns, and an object called @code{NoteColumn} is created
2240 to lay out the notes in that column.
2242 The @code{force-hshift}
2243 property is a property of a @code{NoteColumn} (actually of the
2244 @code{note-column-interface}). Changing it permits a note column
2245 to be moved in units appropriate to a note column, viz. the note
2246 head width of the first voice note. It should be used in
2247 complex situations where the normal @code{\shiftOn} commands (see
2248 @ref{Explicitly instantiating voices}) do
2249 not resolve the note conflict. It is preferable to the
2250 @code{extra-offset} property for this purpose as there is no need
2251 to work out the distance in staff-spaces, and moving the notes
2252 into or out of a @code{NoteColumn} affects other actions such as
2258 Finally, when all else fails, objects may be manually repositioned
2259 relative to the staff center line vertically, or by
2260 displacing them by any distance to a new position. The
2261 disadvantages are that the correct values for the repositioning
2262 have to be worked out, often by trial and error, for every object
2263 individually, and, because the movement is done after LilyPond has
2264 placed all other objects, the user is responsible for avoiding any
2265 collisions that might ensue. But the main difficulty with this
2266 approach is that the repositioning values may need to be reworked
2267 if the music is later modified. The properties that can be used
2268 for this type of manual repositioning are:
2272 @cindex extra-offset property
2273 This property applies to any layout object
2274 supporting the @code{grob-interface}. It takes a pair of
2275 numbers which specify the extra displacement in the horizontal and
2276 vertical directions. Negative numbers move the object to
2277 the left or down. The units are staff-spaces. The extra
2278 displacement is made after the typesetting of objects is
2279 finished, so an object may be repositioned anywhere without
2280 affecting anything else.
2283 @cindex positions property
2284 This is most useful for manually adjusting the slope and height
2285 of beams, slurs, and tuplets. It takes a pair of numbers
2286 giving the position of the left and right ends of the beam, slur,
2287 etc. relative to the center line of the staff. Units are
2288 staff-spaces. Note, though, that slurs and phrasing slurs cannot
2289 be repositioned by arbitrarily large amounts. LilyPond first
2290 generates a list of possible positions for the slur and by default
2291 finds the slur that @qq{looks best}. If the @code{positions}
2292 property has been overridden the slur that is closest to the
2293 requested positions is selected from the list.
2298 A particular object may not have all of these properties.
2299 It is necessary to go to the IR to look up which properties
2300 are available for the object in question.
2302 Here is a list of the objects which are most likely to be
2303 involved in collisions, together with the name of the object which
2304 should be looked up in the IR in order to discover which properties
2305 should be used to move them.
2307 @multitable @columnfractions .5 .5
2308 @headitem Object type @tab Object name
2309 @item Articulations @tab @code{Script}
2310 @item Beams @tab @code{Beam}
2311 @item Dynamics (vertically) @tab @code{DynamicLineSpanner}
2312 @item Dynamics (horizontally) @tab @code{DynamicText}
2313 @item Fingerings @tab @code{Fingering}
2314 @item Rehearsal / Text marks @tab @code{RehearsalMark}
2315 @item Slurs @tab @code{Slur}
2316 @item Text e.g. @code{^"text"} @tab @code{TextScript}
2317 @item Ties @tab @code{Tie}
2318 @item Tuplets @tab @code{TupletBracket}
2322 @node Fixing overlapping notation
2323 @subsection Fixing overlapping notation
2325 Let's now see how the properties in the previous section can
2326 help to resolve overlapping notation.
2328 @subheading padding property
2329 @cindex padding property
2331 The @code{padding} property can be set to increase
2332 (or decrease) the distance between symbols that are printed
2333 above or below notes.
2335 @lilypond[quote,fragment,relative=1,verbatim]
2337 \override Script #'padding = #3
2341 @lilypond[quote,fragment,relative=1,verbatim]
2342 % This will not work, see below:
2343 \override MetronomeMark #'padding = #3
2347 \override Score.MetronomeMark #'padding = #3
2352 Note in the second example how important it is to figure out what
2353 context handles a certain object. Since the @code{MetronomeMark}
2355 is handled in the @code{Score} context, property changes in the
2356 @code{Voice} context will not be noticed. For more details, see
2357 @ruser{Modifying properties}.
2359 If the @code{padding} property of an object is increased when that
2360 object is in a stack of objects being positioned according to
2361 their @code{outside-staff-priority}, then that object and all
2362 objects outside it are moved.
2365 @subheading left-padding and right-padding
2366 @cindex left-padding property
2367 @cindex right-padding property
2369 The @code{right-padding} property affects the spacing between the
2370 accidental and the note to which it applies. It is not often
2371 required, but the following example shows one situation where it
2372 is needed. Suppose we wish to show a chord containing both
2373 a B-natural and a B-flat. To avoid ambiguity we would like to
2374 precede the notes with both a natural and a flat sign. Here
2375 are a few attempts to do this:
2377 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2383 None work, with the second two showing bad collisions between
2386 One way of achieving this is to override the accidental stencil
2387 with a markup containing the natural and flat symbols in the
2388 order we would like, like this:
2390 @lilypond[quote,ragged-right,verbatim]
2391 naturalplusflat = \markup { \natural \flat }
2393 \once \override Accidental
2394 #'stencil = #ly:text-interface::print
2395 \once \override Accidental #'text = #naturalplusflat
2396 \once \override Score.AccidentalPlacement #'right-padding = #1.5
2402 This necessarily uses an override for the accidental stencil which
2403 will not be covered until later. The stencil type must be a
2404 procedure, here changed to print the contents of the @code{text}
2405 property of @code{Accidental}, which itself is set to be a natural
2406 sign followed by a flat sign. These are then moved further away
2407 from the note head by overriding @code{right-padding}.
2411 @subheading staff-padding property
2412 @cindex staff-padding property
2414 @code{staff-padding} can be used to align objects such as dynamics
2415 along a baseline at a fixed height above the staff, rather than
2416 at a height dependent on the position of the note to which they
2417 are attached. It is not a property of
2418 @code{DynamicText} but of @code{DynamicLineSpanner}.
2419 This is because the baseline should apply equally to @strong{all}
2420 dynamics, including those created as extended spanners.
2421 So this is the way to align the dynamic marks in the example
2422 taken from the previous section:
2424 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2426 % Extend width by 1 unit
2427 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
2428 % Align dynamics to a base line 2 units above staff
2429 \override DynamicLineSpanner #'staff-padding = #2
2434 @subheading self-alignment-X property
2435 @cindex self-alignment-X property
2437 The following example shows how this can resolve the collision
2438 of a string fingering object with a note's stem by aligning the
2439 right edge with the reference point of the parent note:
2441 @lilypond[quote,fragment,ragged-right,verbatim,relative=3]
2444 \once \override StringNumber #'self-alignment-X = #RIGHT
2448 @subheading staff-position property
2449 @cindex staff-position property
2451 Multimeasure rests in one voice can collide with notes in another.
2452 Since these rests are typeset centered between the bar lines, it
2453 would require significant effort for LilyPond to figure out which
2454 other notes might collide with it, since all the current collision
2455 handling between notes and between notes and rests is done only
2456 for notes and rests that occur at the same time. Here's an
2457 example of a collision of this type:
2459 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2460 << {c c c c} \\ {R1} >>
2463 The best solution here is to move the multimeasure rest down,
2464 since the rest is in voice two.
2465 The default in @code{\voiceTwo} (i.e. in the second voice of a
2466 @code{<<@{...@} \\ @{...@}>>} construct)
2467 is that @code{staff-position} is set to -4 for MultiMeasureRest,
2468 so we need to move it, say, four half-staff spaces down to
2471 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2475 \override MultiMeasureRest #'staff-position = #-8
2480 This is better than using, for example, @code{extra-offset},
2481 because the ledger line above the rest is inserted automatically.
2483 @subheading extra-offset property
2484 @cindex extra-offset property
2486 The @code{extra-offset} property provides complete control over the
2487 positioning of an object both horizontally and vertically.
2489 In the following example, the second fingering is moved a little to
2490 the left, and 1.8 staff space downwards:
2492 @lilypond[quote,fragment,relative=1,verbatim]
2495 \once \override Fingering
2496 #'extra-offset = #'(-0.3 . -1.8)
2501 @subheading positions property
2502 @cindex positions property
2504 The @code{positions} property allows the position and slope of
2505 tuplets, slurs, phrasing slurs and beams to be controlled
2506 manually. Here's an example which has an ugly phrasing slur
2507 due to its trying to avoid the slur on the acciaccatura.
2509 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2510 r4 \acciaccatura e8\( d8 c ~c d c d\)
2514 We could simply move the phrasing slur above the notes, and this
2515 would be the preferred solution:
2517 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2520 \acciaccatura e8\( d8 c ~c d c d\)
2524 but if there were some reason why this could not be done the
2525 other alternative would be to move the left end of the phrasing
2526 slur down a little using the @code{positions} property. This
2527 also resolves the rather nasty shape.
2529 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2531 \once \override PhrasingSlur #'positions = #'(-4 . -3)
2533 e8\( d8 c ~c d c d\)
2536 Here's a further example taken from the opening of the left-hand
2537 staff of Chopin's Prelude Op 28 No. 2. We see that the beam
2538 collides with the upper notes:
2540 @lilypond[quote,verbatim,fragment,ragged-right]
2543 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2544 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2549 This can be resolved by manually moving both ends of the beam
2550 up from their position at 2 staff-spaces above the center line to,
2553 @lilypond[quote,verbatim,fragment,ragged-right]
2557 \override Beam #'positions = #'(3 . 3)
2562 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2567 Note that the override continues to apply in the first voice of
2568 the second block of quavers, but not to any of the beams in the
2571 @subheading force-hshift property
2572 @cindex force-hshift property
2573 @c FIXME: formatting stuff (ie not important right now IMO)
2574 @c @a nchor Chopin finally corrected TODOgp
2576 We can now see how to apply the final corrections to the Chopin
2577 example introduced at the end of @ref{I'm hearing Voices}, which
2578 was left looking like this:
2580 @lilypond[quote,verbatim,fragment,ragged-right]
2581 \new Staff \relative c'' {
2584 { c2 aes4. bes8 } \\
2596 The lower two notes of the first chord (i.e,
2597 those in the third voice) should not be shifted away from the
2598 note column of the higher two notes. To correct this we set
2599 @code{force-hshift}, which is a property of
2600 @code{NoteColumn}, of these notes to zero.
2601 The lower note of the second chord is best placed just to the
2602 right of the higher notes. We achieve this by setting
2603 @code{force-hshift} of this note to 0.5, ie half a note head's
2604 width to the right of the note column of the higher notes.
2606 Here's the final result:
2608 @lilypond[quote,verbatim,fragment,ragged-right]
2609 \new Staff \relative c'' {
2612 { c2 aes4. bes8 } \\
2615 \once \override NoteColumn #'force-hshift = #0 <ees c>2
2616 \once \override NoteColumn #'force-hshift = #0.5 des2
2624 @node Real music example
2625 @subsection Real music example
2627 We end this section on Tweaks by showing the steps to be taken to
2628 deal with a tricky example which needs several tweaks to produce
2629 the desired output. The example has been deliberately chosen to
2630 illustrate the use of the Notation Reference to resolve unusual
2631 problems with notation. It is not representative of more usual
2632 engraving process, so please do not let these difficulties put
2633 you off! Fortunately, difficulties like these are not very common!
2635 The example is from Chopin's Première Ballade, Op. 23, bars 6 to
2636 9, the transition from the opening Lento to Moderato.
2637 Here, first, is what we want the output to look like, but to avoid
2638 over-complicating the example too much we have left out the
2639 dynamics, fingering and pedalling.
2641 @c The following should appear as music without code
2642 @lilypond[quote,ragged-right]
2643 rhMusic = \relative c'' {
2646 \once \override Tie #'staff-position = #3.5
2650 \mergeDifferentlyHeadedOn
2651 \mergeDifferentlyDottedOn
2652 bes2.^\markup {\bold "Moderato"} r8
2654 {c,8[ d fis bes a] | }
2656 % Reposition the c2 to the right of the merged note
2657 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
2658 % Move the c2 out of the main note column so the merge will work
2661 % Stem on the d2 must be down to permit merging
2662 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
2666 \mergeDifferentlyHeadedOff
2667 \mergeDifferentlyDottedOff
2671 lhMusic = \relative c' {
2673 <d g, d>1)\arpeggio |
2680 \new Staff = "RH" <<
2684 \new Staff = "LH" <<
2693 We note first that the right hand part in the third bar
2694 requires four voices. These are the five beamed eighth notes,
2695 the tied C, the half-note D which is merged with the eighth note
2696 D, and the dotted quarter note F-sharp, which is also merged with
2697 the eighth note at the same pitch. Everything else is in a single
2698 voice, so the easiest way is to introduce these four voices
2699 temporarily at the time they are needed. If you have forgotten
2700 how to do this, look at @ref{I'm hearing Voices}. Let us begin
2701 by entering the notes as two variables and setting up the staff
2702 structure in a score block, and see what LilyPond produces by
2705 @lilypond[quote,verbatim,ragged-right]
2706 rhMusic = \relative c'' {
2711 % Start polyphonic section of four voices
2713 {c,8 d fis bes a | }
2724 lhMusic = \relative c' {
2733 \new Staff = "RH" <<
2737 \new Staff = "LH" <<
2746 All the notes are right, but the appearance is far from
2747 satisfactory. The tie clashes with the change in time signature,
2748 the beaming in the third bar is wrong, the notes are not
2749 merged together, and several notation elements are missing.
2750 Let's first deal with the easier things.
2751 We can correct the beaming by inserting a beam
2752 manually, and we can easily add the left hand slur and the right
2753 hand phrasing slur, since these were all covered in the Tutorial.
2756 @lilypond[quote,verbatim,ragged-right]
2757 rhMusic = \relative c'' {
2762 % Start polyphonic section of four voices
2764 {c,8[ d fis bes a] | }
2775 lhMusic = \relative c' {
2784 \new Staff = "RH" <<
2788 \new Staff = "LH" <<
2797 The first bar is now correct. The second bar contains an arpeggio
2798 and is terminated by a double bar line. How do we do these, as they
2799 have not been mentioned in this Learning Manual? This is where
2800 we need to turn to the Notation Reference. Looking up @q{arpeggio}
2801 and @q{bar line} in the
2802 index quickly shows us that an arpeggio is produced by appending
2803 @code{\arpeggio} to a chord, and a double bar line is produced by
2804 the @code{\bar "||"} command. That's easily done. We next need
2805 to correct the collision of the tie with the time signature. This
2806 is best done by moving the tie upwards. Moving objects was covered
2807 earlier in @ref{Moving objects}, which says that objects positioned
2808 relative to the staff can be moved by overriding their
2809 @code{staff-position} property, which is specified in half staff
2810 spaces relative to the center line of the staff. So the following
2811 override placed just before the first tied note would move the tie
2812 up to 3.5 half staff spaces above the center line:
2814 @code{\once \override Tie #'staff-position = #3.5}
2816 This completes bar two, giving:
2818 @lilypond[quote,verbatim,ragged-right]
2819 rhMusic = \relative c'' {
2821 \once \override Tie #'staff-position = #3.5
2826 % Start polyphonic section of four voices
2828 {c,8[ d fis bes a] | }
2839 lhMusic = \relative c' {
2841 <d g, d>1)\arpeggio |
2848 \new Staff = "RH" <<
2852 \new Staff = "LH" <<
2861 On to bar three and the start of the Moderato section. The
2862 tutorial showed how to add embolded text with the @code{\markup}
2863 command, so adding @q{Moderato} in bold is easy.
2864 But how do we merge notes in different voices together? This is
2865 where we need to turn to the Notation Reference for help. A search
2866 for @qq{merge} in the Notation Reference index quickly leads us to
2867 the commands for merging differently headed and differently
2868 dotted notes in @ruser{Collision resolution}. In our
2869 example we need to merge both types of note for the duration
2870 of the polyphonic section in bar 3, so using the information
2871 we find in the Notation Reference we add
2874 \mergeDifferentlyHeadedOn
2875 \mergeDifferentlyDottedOn
2879 to the start of that section and
2882 \mergeDifferentlyHeadedOff
2883 \mergeDifferentlyDottedOff
2889 @lilypond[quote,verbatim,ragged-right]
2890 rhMusic = \relative c'' {
2892 \once \override Tie #'staff-position = #3.5
2896 bes2.^\markup {\bold "Moderato"} r8
2897 \mergeDifferentlyHeadedOn
2898 \mergeDifferentlyDottedOn
2899 % Start polyphonic section of four voices
2901 {c,8[ d fis bes a] | }
2909 \mergeDifferentlyHeadedOff
2910 \mergeDifferentlyDottedOff
2914 lhMusic = \relative c' {
2916 <d g, d>1)\arpeggio |
2923 \new Staff = "RH" <<
2927 \new Staff = "LH" <<
2936 These overrides have merged the two F-sharp notes, but not the two
2937 on D. Why not? The answer is there in the same section in the
2938 Notation Reference -- notes being merged must have stems in
2939 opposite directions and two notes cannot be merged successfully if
2940 there is a third note in the same note column. Here the two D's
2941 both have upward stems and there is a third note -- the C. We know
2942 how to change the stem direction using @code{\stemDown}, and
2943 the Notation Reference also says how to move the C -- apply a shift
2944 using one of the @code{\shift} commands. But which one?
2945 The C is in voice two which has shift off, and the two D's are in
2946 voices one and three, which have shift off and shift on,
2947 respectively. So we have to shift the C a further level still
2948 using @code{\shiftOnn} to avoid it interfering with the two D's.
2949 Applying these changes gives:
2951 @lilypond[quote,verbatim,ragged-right]
2952 rhMusic = \relative c'' {
2954 \once \override Tie #'staff-position = #3.5
2958 bes2.^\markup {\bold "Moderato"} r8
2959 \mergeDifferentlyHeadedOn
2960 \mergeDifferentlyDottedOn
2961 % Start polyphonic section of four voices
2963 {c,8[ d fis bes a] | }
2965 % Move the c2 out of the main note column so the merge will work
2966 {c,8~ \shiftOnn c2 | }
2968 % Stem on the d2 must be down to permit merging
2969 {s8 \stemDown d2 | }
2973 \mergeDifferentlyHeadedOff
2974 \mergeDifferentlyDottedOff
2978 lhMusic = \relative c' {
2980 <d g, d>1)\arpeggio |
2987 \new Staff = "RH" <<
2991 \new Staff = "LH" <<
3000 Nearly there. Only two problems remain: The downward stem on the
3001 merged D should not be there, and the C would be better positioned
3002 to the right of the D's. We know how to do both of these from the
3003 earlier tweaks: we make the stem transparent, and move the C with
3004 the @code{force-hshift} property. Here's the final result:
3006 @lilypond[quote,verbatim,ragged-right]
3007 rhMusic = \relative c'' {
3010 \once \override Tie #'staff-position = #3.5
3014 bes2.^\markup {\bold "Moderato"} r8
3015 \mergeDifferentlyHeadedOn
3016 \mergeDifferentlyDottedOn
3018 {c,8[ d fis bes a] | }
3020 % Reposition the c2 to the right of the merged note
3021 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
3022 % Move the c2 out of the main note column so the merge will work
3025 % Stem on the d2 must be down to permit merging
3026 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
3030 \mergeDifferentlyHeadedOff
3031 \mergeDifferentlyDottedOff
3035 lhMusic = \relative c' {
3037 <d g, d>1)\arpeggio |
3044 \new Staff = "RH" <<
3048 \new Staff = "LH" <<
3058 @node Further tweaking
3059 @section Further tweaking
3062 * Other uses for tweaks::
3063 * Using variables for tweaks::
3064 * Other sources of information::
3065 * Avoiding tweaks with slower processing::
3066 * Advanced tweaks with Scheme::
3069 @node Other uses for tweaks
3070 @subsection Other uses for tweaks
3072 @cindex transparent property, use of
3073 @cindex objects, making invisible
3074 @cindex removing objects
3075 @cindex objects, removing
3076 @cindex hiding objects
3077 @cindex invisible objects
3078 @cindex tying notes across voices
3080 @subheading Tying notes across voices
3082 The following example demonstrates how to connect notes in
3083 different voices using ties. Normally, only two notes in the
3084 same voice can be connected with ties. By using two voices,
3085 with the tied notes in one of them
3087 @lilypond[quote,fragment,relative=2]
3088 << { b8~ b8\noBeam }
3094 and blanking the first up-stem in that voice, the tie appears to
3097 @lilypond[quote,fragment,relative=2,verbatim]
3100 \once \override Stem #'transparent = ##t
3108 To make sure that the just-blanked stem doesn't squeeze the tie
3109 too much, we can lengthen the stem by setting the
3110 @code{length} to @code{8},
3112 @lilypond[quote,fragment,relative=2,verbatim]
3115 \once \override Stem #'transparent = ##t
3116 \once \override Stem #'length = #8
3124 @subheading Simulating a fermata in MIDI
3126 @cindex stencil property, use of
3127 @cindex fermata, implementing in MIDI
3129 For outside-staff objects it is usually better to override the
3130 object's @code{stencil} property rather than its @code{transparent}
3131 property when you wish to remove it from the printed output.
3132 Setting the @code{stencil} property of an object to @code{#f} will
3133 remove that object entirely from the printed output. This means it
3134 has no effect on the placement of other objects placed relative to
3137 For example, if we wished to change the metronome setting in order
3138 to simulate a fermata in the MIDI output we would not want the
3139 metronome markings to appear in the printed output, and we would
3140 not want it to influence the spacing between the two systems or
3141 the positions of adjacent annotations on the staff. So setting
3142 its @code{stencil} property to @code{#f} would be the best way.
3143 We show here the effect of the two methods:
3145 @lilypond[quote,verbatim,ragged-right]
3148 % Visible tempo marking
3151 \once \override Score.MetronomeMark #'transparent = ##t
3152 % Invisible tempo marking to lengthen fermata in MIDI
3155 % New tempo for next section
3164 @lilypond[quote,verbatim,ragged-right]
3167 % Visible tempo marking
3170 \once \override Score.MetronomeMark #'stencil = ##f
3171 % Invisible tempo marking to lengthen fermata in MIDI
3174 % New tempo for next section
3184 Both methods remove the metronome mark which lengthens the fermata
3185 from the printed output, and both affect the MIDI timing as
3186 required, but the transparent metronome mark in the first line
3187 forces the following tempo indication too high while the
3188 second (with the stencil removed) does not.
3190 @node Using variables for tweaks
3191 @subsection Using variables for tweaks
3193 Override commands are often long and tedious to type, and they
3194 have to be absolutely correct. If the same overrides are to be
3195 used many times it may be worth defining variables to hold them.
3196 Suppose we wish to emphasize certain words in lyrics by printing
3197 them in bold italics. The @code{\italic} and @code{\bold}
3198 commands only work within lyrics if they are also embedded in
3199 @code{\markup}, which makes them tedious to enter, so as an
3200 alternative can we instead use the @code{\override} and
3201 @code{\revert} commands?
3204 @code{\override Lyrics . LyricText #'font-shape = #'italic}
3205 @code{\override Lyrics . LyricText #'font-series = #'bold}
3207 @code{\revert Lyrics . LyricText #'font-shape}
3208 @code{\revert Lyrics . LyricText #'font-series}
3211 These would also be extremely tedious to enter if there were many
3212 words requiring emphasis. So instead we define these as two
3213 variables, and use them as follows, although normally we would
3214 perhaps choose shorter names for the variables to make them
3217 @lilypond[quote,verbatim]
3219 \override Lyrics . LyricText #'font-shape = #'italic
3220 \override Lyrics . LyricText #'font-series = #'bold
3223 \revert Lyrics . LyricText #'font-shape
3224 \revert Lyrics . LyricText #'font-series
3227 global = { \time 4/4 \partial 4 \key c \major}
3228 SopranoMusic = \relative c' { c4 | e4. e8 g4 g | a a g }
3229 AltoMusic = \relative c' { c4 | c4. c8 e4 e | f f e }
3230 TenorMusic = \relative c { e4 | g4. g8 c4. b8 | a8 b c d e4 }
3231 BassMusic = \relative c { c4 | c4. c8 c4 c | f8 g a b c4 }
3232 VerseOne = \lyrics { E -- | ter -- nal \emphasize Fa -- ther, \normal | strong to save, }
3233 VerseTwo = \lyricmode { O | \emphasize Christ, \normal whose voice the | wa -- ters heard, }
3234 VerseThree = \lyricmode { O | \emphasize Ho -- ly Spi -- rit, \normal | who didst brood }
3235 VerseFour = \lyricmode { O | \emphasize Tri -- ni -- ty \normal of | love and pow'r }
3241 \new Voice = "Soprano" { \voiceOne \global \SopranoMusic }
3242 \new Voice = "Alto" { \voiceTwo \AltoMusic }
3243 \new Lyrics \lyricsto "Soprano" { \VerseOne }
3244 \new Lyrics \lyricsto "Soprano" { \VerseTwo }
3245 \new Lyrics \lyricsto "Soprano" { \VerseThree }
3246 \new Lyrics \lyricsto "Soprano" { \VerseFour }
3250 \new Voice = "Tenor" { \voiceOne \TenorMusic }
3251 \new Voice = "Bass" { \voiceTwo \BassMusic }
3259 @node Other sources of information
3260 @subsection Other sources of information
3262 The Internals Reference documentation contains a lot of information
3263 about LilyPond, but even more information can be gathered by
3264 looking at the internal LilyPond files. To explore these, you must
3265 first find the directory appropriate to your system. The location
3266 of this directory depends (a) on whether you obtained LilyPond
3267 by downloading a precompiled binary from lilypond.org
3268 or whether you installed it from a package manager (i.e.
3269 distributed with Linux, or installed under fink or cygwin) or
3270 compiled it from source, and (b) on which operating system it is
3273 @strong{Downloaded from lilypond.org}
3279 @file{@var{INSTALLDIR}/lilypond/usr/share/lilypond/current/}
3284 @file{@var{INSTALLDIR}/LilyPond.app/Contents/Resources/share/lilypond/current/}
3285 by either @code{cd}-ing into this directory from the
3286 Terminal, or control-clicking on the LilyPond application and
3287 selecting @q{Show Package Contents}.
3291 Using Windows Explorer, navigate to
3292 @file{@var{INSTALLDIR}/LilyPond/usr/share/lilypond/current/}
3296 @strong{Installed from a package manager or compiled from source}
3299 @file{@var{PREFIX}/share/lilypond/@var{X.Y.Z}/}, where
3300 @var{PREFIX} is set by your package manager or @code{configure}
3301 script, and @var{X.Y.Z} is the LilyPond version number.
3305 Within this directory the two interesting subdirectories are
3308 @item @file{ly/} - contains files in LilyPond format
3309 @item @file{scm/} - contains files in Scheme format
3312 Let's begin by looking at some files in @file{ly/}.
3313 Open @file{ly/property-init.ly} in a text editor. The one
3314 you normally use for @code{.ly} files will be fine. This file
3315 contains the definitions of all the standard LilyPond built-in
3316 commands, such as @code{\stemUp} and @code{\slurDotted}. You will
3317 see that these are nothing more than definitions of variables
3318 containing one or a group of @code{\override} commands. For
3319 example, @code{/tieDotted} is defined to be:
3323 \override Tie #'dash-period = #0.75
3324 \override Tie #'dash-fraction = #0.1
3328 If you do not like the default values these built-in commands can
3329 be redefined easily, just like any other variable, at the
3330 head of your input file.
3332 The following are the most useful files to be found in
3335 @multitable @columnfractions .4 .6
3338 @item @file{ly/engraver-init.ly}
3339 @tab Definitions of engraver Contexts
3340 @item @file{ly/paper-defaults.ly}
3341 @tab Specifications of paper-related defaults
3342 @item @file{ly/performer-init.ly}
3343 @tab Definitions of performer Contexts
3344 @item @file{ly/property-init.ly}
3345 @tab Definitions of all common built-in commands
3348 Other settings (such as the definitions of markup commands) are
3349 stored as @code{.scm} (Scheme) files. The Scheme programming
3350 language is used to provide a programmable interface into
3351 LilyPond internal operation. Further explanation of these files
3352 is currently outside the scope of this manual, as a knowledge of
3353 the Scheme language is required. Users should be warned that
3354 a substantial amount of technical knowledge or time is required
3355 to understand Scheme and these files (see @ref{Scheme tutorial}).
3357 If you have this knowledge, the Scheme files which may be of
3360 @multitable @columnfractions .4 .6
3363 @item @file{scm/auto-beam.scm}
3364 @tab Sub-beaming defaults
3365 @item @file{scm/define-grobs.scm}
3366 @tab Default settings for grob properties
3367 @item @file{scm/define-markup-commands.scm}
3368 @tab Specify all markup commands
3369 @item @file{scm/midi.scm}
3370 @tab Default settings for MIDI output
3371 @item @file{scm/output-lib.scm}
3372 @tab Settings that affect appearance of frets, colors,
3373 accidentals, bar lines, etc
3374 @item @file{scm/parser-clef.scm}
3375 @tab Definitions of supported clefs
3376 @item @file{scm/script.scm}
3377 @tab Default settings for articulations
3382 @node Avoiding tweaks with slower processing
3383 @subsection Avoiding tweaks with slower processing
3385 LilyPond can perform extra checks while it processes input files. These
3386 checks will take extra time to perform, but fewer manual tweaks
3387 may be required to obtain an acceptable result. If a text script
3388 or part of the lyrics extends over the margins these checks will
3389 compress that line of the score just enough to fit within the
3392 To be effective under all circumstances these checks must be enabled
3393 by placing the overrides in a Score @code{\with} block, rather than
3394 in-line in music, as follows:
3398 % Makes sure text scripts and lyrics are within the paper margins
3399 \override PaperColumn #'keep-inside-line = ##t
3400 \override NonMusicalPaperColumn #'keep-inside-line = ##t
3406 @node Advanced tweaks with Scheme
3407 @subsection Advanced tweaks with Scheme
3409 Although many things are possible with the @code{\override} and
3410 @code{\tweak} commands, an even more powerful way of modifying
3411 the action of LilyPond is available through a programmable
3412 interface to the LilyPond internal operation. Code written in
3413 the Scheme programming language can be incorporated directly in
3414 the internal operation of LilyPond. Of course, at least a basic
3415 knowledge of programming in Scheme is required to do this, and an
3416 introduction is provided in the @ref{Scheme tutorial}.
3418 As an illustration of one of the many possibilities, instead of
3419 setting a property to a constant it can be set to a Scheme
3420 procedure which is then called whenever that property is accessed
3421 by LilyPond. The property can then be set dynamically to a value
3422 determined by the procedure at the time it is called. In this
3423 example we color the note head in accordance with its position on
3426 @lilypond[quote,verbatim,ragged-right]
3427 #(define (color-notehead grob)
3428 "Color the notehead according to its position on the staff."
3429 (let ((mod-position (modulo (ly:grob-property grob 'staff-position) 7)))
3431 ;; Return rainbow colors
3432 ((1) (x11-color 'red )) ; for C
3433 ((2) (x11-color 'orange )) ; for D
3434 ((3) (x11-color 'yellow )) ; for E
3435 ((4) (x11-color 'green )) ; for F
3436 ((5) (x11-color 'blue )) ; for G
3437 ((6) (x11-color 'purple )) ; for A
3438 ((0) (x11-color 'violet )) ; for B
3444 % Arrange to obtain color from color-notehead procedure
3445 \override NoteHead #'color = #color-notehead
3452 Some -- where o -- ver the Rain -- bow, way up high,
3456 Further examples showing the use of these programmable interfaces
3457 can be found in @ref{Tweaking with Scheme}.