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2 @c This file is part of lilypond-learning.tely
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11 @chapter Tweaking output
13 This chapter discusses how to modify output. LilyPond is extremely
14 configurable; virtually every fragment of output may be changed.
19 * The Internals Reference manual::
20 * Appearance of objects::
21 * Placement of objects::
22 * Collisions of objects::
27 @section Tweaking basics
30 * Introduction to tweaks::
31 * Objects and interfaces::
32 * Naming conventions of objects and properties::
36 @node Introduction to tweaks
37 @subsection Introduction to tweaks
39 @q{Tweaking} is a LilyPond term for the various methods available
40 to the user for modifying the actions taken during interpretation
41 of the input file and modifying the appearance of the printed
42 output. Some tweaks are very easy to use; others are more
43 complex. But taken together the methods available for tweaking
44 permit almost any desired appearance of the printed music to be
47 In this section we cover the basic concepts required to understand
48 tweaking. Later we give a variety of ready-made commands which can
49 simply be copied to obtain the same effect in your own scores, and
50 at the same time we show how these commands may be constructed so
51 that you may learn how to develop your own tweaks.
53 Before starting on this Chapter you may wish to review the section
54 @ref{Contexts and engravers}, as Contexts, Engravers, and the
55 Properties contained within them are fundamental to understanding
56 and constructing Tweaks.
58 @node Objects and interfaces
59 @subsection Objects and interfaces
66 Tweaking involves modifying the internal operation and structures
67 of the LilyPond program, so we must first introduce some terms
68 which are used to describe those internal operations and
71 The term @q{Object} is a generic term used to refer to the
72 multitude of internal structures built by LilyPond during the
73 processing of an input file. So when a command like @code{\new
74 Staff} is encountered a new object of type @code{Staff} is
75 constructed. That @code{Staff} object then holds all the
76 properties associated with that particular staff, for example, its
77 name and its key signature, together with details of the engravers
78 which have been assigned to operate within that staff's context.
79 Similarly, there are objects to hold the properties of all other
80 contexts, such as @code{Voice} objects, @code{Score} objects,
81 @code{Lyrics} objects, as well as objects to represent all
82 notational elements such as bar lines,
83 note heads, ties, dynamics, etc. Every object has its own set of
86 Some types of object are given special names. Objects which
87 represent items of notation on the printed output such as
88 note heads, stems, slurs, ties, fingering, clefs, etc are called
89 @q{Layout objects}, often known as @q{Graphical Objects}, or
90 @q{Grobs} for short. These are still objects in the generic sense
91 above, and so they too all have properties associated with them,
92 such as their position, size, color, etc.
94 Some layout objects are still more specialised. Phrasing slurs,
95 crescendo hairpins, ottavo marks, and many other grobs are not
96 localised in a single place -- they have a starting point, an
97 ending point, and maybe other properties concerned with their
98 shape. Objects with an extended shape like these are called
101 It remains to explain what @q{Interfaces} are. Many objects,
102 even though they are quite different, share common features
103 which need to be processed in the same way.
104 For example, all grobs have a color, a size, a position, etc,
105 and all these properties are processed in the same way during
107 interpretation of the input file. To simplify these internal
108 operations these common actions and properties are grouped
109 together in an object called a @code{grob-interface}. There
110 are many other groupings of common properties like this, each
111 one given a name ending in @code{-interface}. In total there
112 are over 100 such interfaces. We shall see later why this is
113 of interest and use to the user.
115 These, then, are the main terms relating to objects which we
116 shall use in this chapter.
118 @node Naming conventions of objects and properties
119 @subsection Naming conventions of objects and properties
121 We met some object naming conventions previously, in
122 @ref{Contexts and engravers}. Here for reference is a list
123 of the most common object and property types together with
124 the conventions for naming them and a couple of examples of
125 some real names. We have used A to stand for any capitalised
126 alphabetic character and aaa to stand for any number of
127 lower-case alphabetic characters. Other characters are used
130 @multitable @columnfractions .33 .33 .33
131 @headitem Object/property type
132 @tab Naming convention
135 @tab Aaaa or AaaaAaaaAaaa
136 @tab Staff, GrandStaff
138 @tab Aaaa or AaaaAaaaAaaa
141 @tab Aaaa_aaa_engraver
142 @tab Clef_engraver, Note_heads_engraver
144 @tab aaa-aaa-interface
145 @tab grob-interface, break-aligned-interface
146 @item Context Properties
147 @tab aaa or aaaAaaaAaaa
148 @tab alignAboveContext, skipBars
149 @item Layout Object Properties
150 @tab aaa or aaa-aaa-aaa
151 @tab direction, beam-thickness
154 As we shall see shortly, the properties of different types of
155 object are modified by different commands, so it is useful to
156 be able to recognise the type of object from the names of its
160 @node Tweaking methods
161 @subsection Tweaking methods
164 @item @strong{override command}
166 @cindex override command
169 We have already met the commands @code{\set} and @code{\with},
170 used to change the properties of @strong{contexts} and to remove
171 and add @strong{engravers}, in
172 @ref{Modifying context properties} and @ref{Adding
173 and removing engravers}. We now must meet one more important
176 The command to change the properties of @strong{layout objects} is
177 @code{\override}. Because this command has to modify
178 internal properties deep within LilyPond its syntax is not
179 as simple as the commands you have met so far. It needs to
180 know precisely which property of which object in which context
181 has to be modified, and what its new value is to be. Let's see
184 The general syntax of this command is:
187 \override @emph{context}.@emph{layout_object} #'@emph{layout_property} = #@emph{value}
191 This will set the property with the name @emph{layout_property}
192 of the layout object with the name
193 @emph{layout_object}, which is a member of the @emph{context}
194 context, to the value @emph{value}.
196 The @emph{context} can be omitted (and usually is) when the
197 required context is unambiguously implied and is one of lowest
198 level contexts, i.e., @code{Voice}, @code{ChordNames} or
199 @code{Lyrics}, and we shall omit it in many of the following
200 examples. We shall see later when it must be specified.
202 For now, don't worry about the @code{#'}, which must precede the
203 layout property, and the @code{#}, which must precede the value.
204 These must always be present in exactly this form. This is the
205 most common command used in tweaking, and most of the rest of
206 this chapter will be directed to presenting examples of how it is
209 Once overridden, the property retains its new value until it is
210 overridden again or a @code{\revert} command is encountered.
211 The @code{\revert} command has the following syntax and causes
212 the value of the property to revert to its original default
213 value; note, not its previous value if several @code{\override}
214 commands have been issued.
217 \revert @emph{context}.@emph{layout_object} #'@emph{layout_property}
220 Again, just like @emph{context} in the @code{\override} command,
221 @emph{context} is often not needed. It will be omitted
222 in many of the following examples.
224 @item @strong{overrideProperty command}
226 @cindex overrideProperty command
227 @funindex \overrideProperty
229 There is another form of the override command,
230 @code{\overrideProperty}, which is occasionally required.
231 We mention it here for completeness, but for details see
232 @ruser{Difficult tweaks}.
233 @c Maybe explain in a later iteration -td
235 @item @strong{tweak command}
237 @cindex tweak command
240 The final tweaking command which is available is @code{\tweak}.
241 This should be used to change the properties of objects which
242 occur at the same musical moment, such as the notes within a
243 chord. Using @code{\override} would affect all the notes
244 within a chord, whereas @code{\tweak} affects just the following
245 item in the input stream.
247 Here's an example. Suppose we wish to change the size of the
248 middle note (the E) in a C major chord. Let's first see what
249 @code{\once \override} would do:
251 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
253 \once \override NoteHead #'font-size = #-3
257 We see the override affects @emph{all} the notes in the chord.
258 This is because all the notes of a chord occur at the same
259 @emph{musical moment}, and the action of @code{\once} is to
260 apply the override to all layout objects of the type specified
261 which occur at the same musical moment as the @code{\override}
264 The @code{\tweak} command operates in a different way. It acts
265 on the immediately following item in the input stream. However,
266 it is effective only on objects which are created directly from
267 the input stream, essentially note heads and articulations.
268 (Objects such as stems and accidentals are created later and
269 cannot be tweaked in this way). Furthermore, when it is applied
270 to note heads these must be within a chord, i.e., within single
271 angle brackets, so to tweak a single note the @code{\tweak}
272 command must be placed inside single angle brackets with the
275 So to return to our example, the size of the middle note of
276 a chord would be changed in this way:
278 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
280 <c \tweak #'font-size #-3 e g>4
283 Just one in a series of articulations can be modified with
284 @code{\tweak}, as shown here:
286 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
288 -\tweak #'color #red ^Red
289 -\tweak #'color #green _Green
292 Note that the @code{\tweak} command must be preceded by an
293 articulation mark as if it were an articulation itself.
295 You can find more details of the @code{\tweak} command in
296 @ruser{Objects connected to the input}.
301 @node The Internals Reference manual
302 @section The Internals Reference manual
304 @cindex Internals Reference
307 * Properties of layout objects::
308 * Properties found in interfaces::
309 * Types of properties::
312 @node Properties of layout objects
313 @subsection Properties of layout objects
315 @cindex properties of layout objects
316 @cindex properties of grobs
317 @cindex grobs, properties of
318 @cindex layout objects, properties of
320 Suppose you have a slur in a score which, to your mind,
321 appears too thin and you'd like to draw it a little heavier.
322 How do you go about doing this? You know from the statements
323 earlier about the flexibility of LilyPond that such a thing
324 should be possible, and you would probably guess that an
325 @code{\override} command would be needed. But is there a
326 heaviness property for a slur, and if there is, how might it
327 be modified? This is where the Internals Reference manual
328 comes in. It contains all the information you might need to
329 construct this and all other @code{\override} commands.
331 Before we look at the Internals Reference a word of warning.
332 This is a @strong{reference} document, which means there is
333 little or no explanation contained within it: its purpose is
334 to present information precisely and concisely. This
335 means it might look daunting at first sight. Don't worry!
336 The guidance and explanation presented here will enable you
337 to extract the information from the Internals Reference for
338 yourself with just a little practice.
340 @cindex override example
341 @cindex Internals Reference, example of using
343 Let's use a concrete example with a simple fragment of real
346 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
351 g[( e]) e d[( f]) a |
355 The man who feels love's sweet e -- mo -- tion
360 Suppose now that we decide we would like the slurs to be a
361 little heavier. Is this possible? The slur is certainly a
362 layout object, so the question is, @q{Is there a property
363 belonging to a slur which controls the heaviness?} To answer
364 this we must look in the Internals Reference, or IR for short.
366 The IR for the version of LilyPond you are using may be found
367 on the LilyPond website at @uref{http://lilypond.org}. Go to the
368 documentation page and click on the Internals Reference link.
369 For learning purposes you should use the standard html version,
370 not the @q{one big page} or the PDF. For the next few
371 paragraphs to make sense you will need to actually do this
374 Under the heading @strong{Top} you will see five links. Select
375 the link to the @emph{Backend}, which is where information about
376 layout objects is to be found. There, under the heading
377 @strong{Backend}, select the link to @emph{All layout objects}.
378 The page that appears lists all the layout objects used in your
379 version of LilyPond, in alphabetic order. Select the link to
380 Slur, and the properties of Slurs are listed.
382 (An alternative way of finding this page is from the Notation
383 Reference. On one of the pages that deals with slurs you may
384 find a link to the Internals Reference. This link will
385 take you directly to this page, but often it is easier to go
386 straight to the IR and search there.)
388 This Slur page in the IR tells us first that Slur objects are
390 Slur_engraver. Then it lists the standard settings. Note
391 these are @strong{not} in alphabetic order. Browse down
392 them looking for a property that might control the heaviness
393 of slurs, and you should find
396 @code{thickness} (number)
398 Line thickness, generally measured in @code{line-thickness}
401 This looks a good bet to change the heaviness. It tells us that
402 the value of @code{thickness} is a simple @emph{number},
403 that the default value is 1.2, and that the units are
404 in another property called @code{line-thickness}.
406 As we said earlier, there are few to no explanations in the IR,
407 but we already have enough information to try changing the
408 slur thickness. We see that the name of the layout object
409 is @code{Slur}, that the name of the property to change is
410 @code{thickness} and that the new value should be a number
411 somewhat larger than 1.2 if we are to make slurs thicker.
413 We can now construct the @code{\override} command by simply
414 substituting the values we have found for the names, omitting
415 the context. Let's use a very large value for the thickness
416 at first, so we can be sure the command is working. We get:
419 \override Slur #'thickness = #5.0
422 Don't forget the @code{#'} preceding the
423 property name and and @code{#} preceding the new value!
425 The final question is, @q{Where should this command be
426 placed?} While you are unsure and learning, the best
427 answer is, @q{Within the music, before the first slur and
428 close to it.} Let's do that:
430 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
434 % Increase thickness of all following slurs from 1.2 to 5.0
435 \override Slur #'thickness = #5.0
437 g[( e]) e d[( f]) a |
441 The man who feels love's sweet e -- mo -- tion
447 and we see that the slur is indeed heavier.
449 So this is the basic way of constructing @code{\override}
450 commands. There are a few more complications that we
451 shall meet in later sections, but you now know all the
452 essentials required to make up your own -- but you will
453 still need some practice. This is provided in the examples
456 @subheading Finding the context
457 @cindex context, finding
459 But first, what if we had needed to specify the Context?
460 What should it be? We could guess that slurs are in
461 the Voice context, as they are clearly closely associated
462 with individual lines of music, but can we be sure? To
463 find out, go back to the top of the IR page describing the
464 Slur, where it says @q{Slur objects are created by: Slur
465 engraver}. So slurs will be created in whichever context
466 the @code{Slur_engraver} is in. Follow the link to the
467 @code{Slur_engraver} page. At the very bottom it tells
468 us that @code{Slur_engraver} is part of five Voice contexts,
469 including the standard voice context, @code{Voice}, so our
470 guess was correct. And because @code{Voice} is one of the
471 lowest level contexts which is implied unambiguously by
472 the fact that we are entering notes, we can omit it in this
475 @subheading Overriding once only
477 @cindex overriding once only
478 @cindex once override
481 As you can see, @emph{all} the slurs are thicker in the
482 final example above. But what if we
483 wanted just the first slur to be thicker? This is achieved
484 with the @code{\once} command. Placed immediately before
485 the @code{\override} command it causes it to change only the
486 slur which begins on the @strong{immediately following} note.
488 immediately following note does not begin a slur the command
489 has no effect at all -- it is not remembered until a slur
490 is encountered, it is simply discarded. So the command with
492 repositioned as follows:
494 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
499 % Increase thickness of immediately following slur only
500 \once \override Slur #'thickness = #5.0
502 g[( e]) e d[( f]) a |
506 The man who feels love's sweet e -- mo -- tion
512 Now only the first slur is made heavier.
514 The @code{\once} command can also be used before @code{\set}
515 and @code{\unset}, and before the command to be introduced
516 in the following section -- @code{revert}.
518 @subheading Reverting
521 @cindex default properties, reverting
524 Finally, what if we wanted just the first two slurs to be
525 heavier? Well, we could use two commands, each preceded by
526 @code{\once} placed immediately before each of the notes where
529 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
534 % Increase thickness of immediately following slur only
535 \once \override Slur #'thickness = #5.0
537 % Increase thickness of immediately following slur only
538 \once \override Slur #'thickness = #5.0
539 g[( e]) e d[( f]) a |
543 The man who feels love's sweet e -- mo -- tion
549 or we could omit the @code{\once} command and use the
550 @code{\revert} command
551 to return the @code{thickness} property to its default value
552 after the second slur:
554 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
559 % Increase thickness of all following slurs from 1.2 to 5.0
560 \override Slur #'thickness = #5.0
563 % Revert thickness of all following slurs to default of 1.2
564 \revert Slur #'thickness
569 The man who feels love's sweet e -- mo -- tion
575 The @code{\revert} command can be used to return any property
576 changed with @code{\override} back to its default value.
577 You may use whichever method best suits what you want to do.
579 That concludes our introduction to the IR, and the basic
580 method of tweaking. Several examples follow in the later
581 sections of this Chapter, partly to introduce you to some of the
582 additional features of the IR, and partly to give you more
583 practice in extracting information from it. These examples will
584 contain progressively fewer words of guidance and explanation.
586 @node Properties found in interfaces
587 @subsection Properties found in interfaces
589 @cindex interface properties
590 @cindex properties in interfaces
592 Suppose now that we wish to print the lyrics in italics. What
593 form of @code{\override} command do we need to do this?
594 We first look in the IR page listing @q{All layout objects}, as
595 before, and look for an object that might control lyrics. We
596 find @code{LyricText}, which looks right. Clicking on this shows
597 the settable properties for lyric text. These include the
598 @code{font-series} and @code{font-size}, but nothing that might
599 give an italic shape.
600 This is because the shape property is one that is common to all
601 font objects, so, rather than including it in every layout
602 object, it is grouped together with other similar common
603 properties and placed in an @strong{Interface}, the
604 @code{font-interface}.
606 So now we need to learn how to find the properties of interfaces,
607 and to discover what objects use these interface properties.
609 Look again at the IR page which describes LyricText. At the
610 bottom of the page is a list of clickable (in the html versions
611 of the IR) interfaces which LyricText supports. The list has
612 seven items, including @code{font-interface}.
613 Clicking on this brings up the properties associated
614 with this interface, which are also properties of all the objects
615 which support it, including LyricText.
617 Now we see all the user-settable properties which control fonts,
618 including @code{font-shape(symbol)}, where @code{symbol} can be
619 set to @code{upright}, @code{italics} or @code{caps}.
621 You will notice that that @code{font-series} and @code{font-size}
622 are also listed there.
623 This immediately raises the question: Why are the common font
624 properties @code{font-series} and @code{font-size} listed under
625 @code{LyricText} as well as under the interface
626 @code{font-interface} but @code{font-shape} is not? The answer
627 is that @code{font-series} and @code{font-size} are changed
628 from their global default values when a @code{LyricText} object
629 is created, but @code{font-shape} is not. The entries in
630 @code{LyricText} then tell you the values for those two
631 properties which apply to @code{LyricText}. Other objects
632 which support @code{font-interface} will set these
633 properties diferently when they are created.
635 Let's see if we can now construct the @code{\override} command
636 to change the lyrics to italics. The object is @code{LyricText},
637 the property is @code{font-shape} and the value is
638 @code{italic}. As before, we'll omit the context.
640 As an aside, although it is an important one, note that because
642 @code{font-shape} are symbols they must be introduced with a
643 single apostrophe, @code{'}. That is why apostrophes
644 are needed before @code{thickness} in the earlier example
645 and @code{font-shape}. These are both symbols too.
646 Symbols are special names which are known internally to
647 LilyPond. Some of them are the names of properties,
648 like @code{thickness} or @code{font-shape}, others are in
649 effect special values that can be given to properties, like
650 @code{italic}. Note the distinction from arbitary
651 text strings, which would appear as @code{"a text string"}.
653 Ok, so the @code{\override} command we need to print the lyrics
657 \override LyricText #'font-shape = #'italic
661 and this should be placed just in front of and close to the
662 lyrics which it should affect, like this:
664 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
669 g[( e]) e d[( f]) a |
673 \override LyricText #'font-shape = #'italic
674 The man who feels love's sweet e -- mo -- tion
680 and the lyrics are all printed in italics.
682 @subheading Specifying context in lyric mode
683 @cindex context, specifying in lyric mode
685 In the case of lyrics, if you try specifying the context in the
686 format given earlier the command will fail. A syllable
687 entered in lyricmode is terminated by either a space,
688 a newline or a digit. All other characters are included
689 as part of the syllable. For this reason a space or newline
690 must appear before the terminating @code{@}} to prevent it being
691 included as part of the final syllable. Similarly,
692 spaces must be inserted before and after the
693 period or dot, @q{.}, separating the context name from the
694 object name, as otherwise the two names are run together and
695 the interpreter cannot recognise them. So the command should be:
698 \override Lyrics . LyricText #'font-shape = #'italic
701 @warning{In lyrics always leave whitespace between the final
702 syllable and the terminating brace.}
704 @warning{In overrides in lyrics always place spaces around
705 the dot between the context name and the object name.}
707 @node Types of properties
708 @subsection Types of properties
710 @cindex Property types
712 So far we have seen two types of property: @code{number} and
713 @code{symbol}. To be valid, the value given to a property
714 must be of the correct type and obey the rules for that type.
715 The type of property is always shown in brackets after the
716 property name in the IR. Here is a list of the types you may
717 need, together with the rules for that type, and some examples.
718 You must always add a hash symbol, @code{#}, of course,
719 to the front of these values when they are entered in the
720 @code{\override} command.
722 @multitable @columnfractions .2 .45 .35
723 @headitem Property type
727 @tab Either True or False, represented by #t or #f
728 @tab @code{#t}, @code{#f}
729 @item Dimension (in staff space)
730 @tab A positive decimal number (in units of staff space)
731 @tab @code{2.5}, @code{0.34}
733 @tab A valid direction constant or its numerical equivalent
734 @tab @code{#LEFT}, @code{#CENTER}, @code{#UP},
737 @tab A positive whole number
738 @tab @code{3}, @code{1}
740 @tab A bracketed set of items separated by spaces,
741 preceded by an apostrophe
742 @tab @code{'(left-edge staff-bar)}, @code{'(1)},
743 @code{'(1.0 0.25 0.5)}
745 @tab Any valid markup
746 @tab @code{\markup @{ \italic "cresc." @}}
748 @tab A fraction of a whole note constructed with the
750 @tab @code{(ly:make-moment 1 4)},
751 @code{(ly:make-moment 3 8)}
753 @tab Any positive or negative decimal value
754 @tab @code{3.5}, @code{-2.45}
755 @item Pair (of numbers)
756 @tab Two numbers separated by a @q{space . space} and enclosed
757 in brackets preceded by an apostrophe
758 @tab @code{'(2 . 3.5)}, @code{'(0.1 . -3.2)}
760 @tab Any of the set of permitted symbols for that property,
761 preceded by an apostrophe
762 @tab @code{'italic}, @code{'inside}
764 @tab A procedure or @code{#f} (to cause no action)
765 @tab @code{bend::print}, @code{ly:text-interface::print},
768 @tab A list of three items enclosed in brackets and preceded
769 by a hash sign, @code{#}.
770 @tab @code{#(#t #t #f)}
773 @node Appearance of objects
774 @section Appearance of objects
776 Let us now put what we have learnt into practice with a few
777 examples which show how tweaks may be used to change the
778 appearance of the printed music.
781 * Visibility and color of objects::
783 * Length and thickness of objects::
786 @node Visibility and color of objects
787 @subsection Visibility and color of objects
789 In the educational use of music we might wish to print a score
790 with certain elements omitted as an exercise for the student,
791 who is required to supply them. As a simple example,
792 let us suppose the exercise is to supply the missing bar lines
793 in a piece of music. But the bar lines are normally inserted
794 automatically. How do we prevent them printing?
796 Before we tackle this, let us remember that object properties
797 are grouped in what are called @emph{interfaces} -- see
798 @ref{Properties found in interfaces}. This is simply to
799 group together those properties that are commonly required
800 together -- if one of them is required for an object, so are
801 the others. Some objects then need the properties in some
802 interfaces, others need them from other interfaces. The
803 interfaces which contain the properties required by a
804 particular grob are listed in the IR at the bottom of the
805 page describing that grob, and those properties may be
806 viewed by looking at those interfaces.
808 We explained how to find information about grobs in
809 @ref{Properties of layout objects}. Using the same approach,
810 we go to the IR to find the layout object which prints
811 bar lines. Going via @emph{Backend} and @emph{All layout objects}
813 is a layout object called @code{BarLine}. Its properties include
814 two that control its visibility: @code{break-visibility} and
815 @code{stencil}. Barline also supports a number of interfaces,
816 including the @code{grob-interface}, where we find the
817 @code{transparent} and the @code{color} properties. All
818 of these can affect the visibility of bar lines (and, of course,
819 by extension, many other layout objects too.) Let's consider
820 each of these in turn.
823 @cindex stencil property
825 This property controls the appearance of the bar lines by specifying
826 the symbol (glyph) which should be printed. In common
827 with many other properties, it can be set to print nothing by
828 setting its value to @code{#f}. Let's try it, as before, omitting
829 the implied Context, @code{Voice}:
831 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
834 \override BarLine #'stencil = ##f
841 The bar lines are still printed. What is wrong? Go back to the
842 IR and look again at the page giving the properties of BarLine.
843 At the top of the page it says @qq{Barline objects are created
844 by: Bar_engraver}. Go to the @code{Bar_engraver} page.
846 it gives a list of Contexts in which the bar engraver operates.
847 All of them are of the type @code{Staff}, so the reason the
848 @code{\override} command failed to work as expected is because
849 @code{Barline} is not in the default @code{Voice} context.
851 is specified wrongly, the command simply does not work. No
852 error message is produced, and nothing is logged in the log
853 file. Let's try correcting it by adding the correct context:
855 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
858 \override Staff.BarLine #'stencil = ##f
865 Now the bar lines have vanished.
867 @subheading break-visibility
869 @cindex break-visibility property
871 We see from the @code{BarLine} properties in the IR that the
872 @code{break-visibility} property requires a vector of three
874 These control respectively whether bar lines are printed at
875 the end of a line, in the middle of lines, and at the beginning
876 of lines. For our example we want all bar lines to be suppressed,
877 so the value we need is @code{#(#f #f #f)}.
878 Let's try that, remembering
879 to include the @code{Staff} context. Note also that in writing
880 this value we have two hash signs before the opening bracket.
881 One is required as part of the value to introduce a vector,
882 and one is required, as always, to precede the value itself in
883 the @code{\override} command.
885 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
888 \override Staff.BarLine #'break-visibility = ##(#f #f #f)
895 And we see this too removes all the bar lines.
897 @subheading transparent
898 @cindex transparent property
900 We see from the properties specified in the @code{grob-interface}
901 page in the IR that the @code{transparent} property is a boolean.
903 should be set to @code{#t} to make the grob transparent.
904 In this next example let us make the time signature invisible
905 rather than the bar lines.
906 To do this we need to find the grob name for the time signature.
908 the @q{All layout objects} page in the IR to find the properties
909 of the @code{TimeSignature} layout object. This is produced by
910 the @code{Time_signature_engraver} which you can check also lives
911 in the @code{Staff} context and also supports the
912 @code{grob-interface}. So the command to make the time signature
915 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
918 \override Staff.TimeSignature #'transparent = ##t
926 The time signature is gone, but this command leaves a gap where
927 the time signature should be. Maybe this is what is wanted for
928 an exercise for the student to fill it in, but in other
929 circumstances a gap might be undesirable. To remove it, the
930 stencil for the time signature should be set to @code{#f}
933 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
936 \override Staff.TimeSignature #'stencil = ##f
944 and the difference is obvious: setting the stencil to @code{#f}
945 removes the object entirely; making the object @code{transparent}
946 leaves it where it is, but makes it invisible.
949 @cindex color property
951 Finally we could make the bar lines invisible by coloring
952 them white. The @code{grob-interface} specifies that the
953 color property value is a list, but there is no
954 explanation of what that list should be. The list it
955 requires is actually a list of values in internal units,
956 but, to avoid having to know what these are, several ways
957 are provided to specify colors. The first way is to use one
958 of the @q{normal} colours listed in the first table in
959 @ruser{List of colors}. To set the bar lines to white
962 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
965 \override Staff.BarLine #'color = #white
973 and again, we see the bar lines are not visible. Note that
974 @emph{white} is not preceded by an apostrophe -- it is not
975 a symbol, but a @emph{function}. When called, it provides
976 the list of internal values required to set the color to
977 white. The other colors in the normal list are functions
978 too. To convince yourself this is working you might like
979 to change the color to one of the other functions in the
985 The second way of changing the color is to use the list of
986 X11 color names in the second list in @ruser{List of colors}.
987 However, these must be preceded by another function, which
988 converts X11 color names into the list of internal values,
989 @code{x11-color}, like this:
991 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
994 \override Staff.BarLine #'color = #(x11-color 'white)
1002 Note that in this case the function @code{x11-color} takes
1003 a symbol as an argument, so the symbol must be preceded by
1004 an apostrophe and the two enclosed in brackets.
1009 There is yet a third function, one which converts RGB values into
1010 internal colors -- the @code{rgb-color} function. This takes
1011 three arguments giving the intensities of the red, green and
1012 blue colors. These take values in the range 0 to 1. So to
1013 set the color to red the value should be @code{(rgb-color 1 0 0)}
1014 and to white it should be @code{(rgb-color 1 1 1)}:
1016 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1019 \override Staff.BarLine #'color = #(rgb-color 1 1 1)
1021 g, a16 b8 c d4 e16 |
1026 Finally, there is also a grey scale available as part of the
1027 X11 set of colors. These range from black, @code{'grey0'},
1028 to white, @code{'grey100}, in steps of 1. Let's illustrate
1029 this by setting all the layout objects in our example to
1030 various shades of grey:
1032 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1035 \override Staff.StaffSymbol #'color = #(x11-color 'grey30)
1036 \override Staff.TimeSignature #'color = #(x11-color 'grey60)
1037 \override Staff.Clef #'color = #(x11-color 'grey60)
1038 \override Voice.NoteHead #'color = #(x11-color 'grey85)
1039 \override Voice.Stem #'color = #(x11-color 'grey85)
1040 \override Staff.BarLine #'color = #(x11-color 'grey10)
1042 g, a16 b8 c d4 e16 |
1048 Note the contexts associated with each of the layout objects.
1049 It is important to get these right, or the commands will not
1050 work! Remember, the context is the one in which the appropriate
1051 engraver is placed. The default context for engravers can be
1052 found by starting from the layout object, going from there to
1053 the engraver which produces it, and on the engraver page in the
1054 IR it tells you in which context the engraver will normally be
1058 @node Size of objects
1059 @subsection Size of objects
1061 Let us begin by looking again at the earlier example
1062 see @ref{Nesting music expressions}) which showed
1063 how to introduce a new temporary staff, as in an @rglos{ossia}.
1065 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1066 \new Staff ="main" {
1073 alignAboveContext = "main" }
1081 Ossia are normally written without clef and time signature, and
1082 are usually printed slightly smaller than the main staff. We
1083 already know now how to remove the clef and time signature --
1084 we simply set the stencil of each to @code{#f}, as follows:
1086 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1087 \new Staff ="main" {
1094 alignAboveContext = "main"
1097 \override Staff.Clef #'stencil = ##f
1098 \override Staff.TimeSignature #'stencil = ##f
1108 where the extra pair of braces after the @code{\with} clause are
1109 required to ensure the enclosed overrrides and music are applied
1112 But what is the difference between modifying the staff context by
1113 using @code{\with} and modifying the stencils of the clef and the
1114 time signature with \override? The main difference is that
1115 changes made in a @code{\with} clause are made at the time the
1116 context is created, and remain in force as the @strong{default}
1117 values for the duration of that context, whereas
1118 @code{\set} or @code{\override} commands embedded in the
1119 music are dynamic -- they make changes synchronised with
1120 a particular point in the music. If changes are unset or
1121 reverted using @code{\unset} or @code{\revert} they return to
1122 their default values, which will be the ones set in the
1123 @code{\with} clause, or if none have been set there, the normal
1126 Some context properties
1127 can be modified only in @code{\with} clauses. These are those
1128 properties which cannot sensibly be changed after the context
1129 has been created. @code{alignAboveContext} and its partner,
1130 @code{alignBelowContext}, are two such properties -- once the
1131 staff has been created its alignment is decided and it would
1132 make no sense to try to change it later.
1134 The default values of layout object properties can also be set
1135 in @code{\with} clauses. Simply use the normal @code{\override}
1136 command leaving out the context name, since this is unambiguously
1137 defined as the context which the @code{\with} clause is modifying.
1138 If fact, an error will be generated if a context is specified
1141 So we could replace the example above with
1143 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1144 \new Staff ="main" {
1151 alignAboveContext = "main"
1152 % Don't print clefs in this staff
1153 \override Clef #'stencil = ##f
1154 % Don't print time signatures in this staff
1155 \override TimeSignature #'stencil = ##f
1164 Finally we come to changing the size of layout objects.
1166 Some layout objects are created as glyphs selected from
1167 a typeface font. These include note heads, accidentals, markup,
1168 clefs, time signatures, dynamics and lyrics.
1169 Their size is changed by modifying the
1170 @code{font-size} property, as we shall shortly see. Other
1171 layout objects such as slurs and ties -- in general, spanner
1172 objects -- are drawn individually, so there is no
1174 associated with them. These objects generally derive their
1175 size from the objects to which they are attached, so usually
1176 there is no need to change their size manually. Still other
1177 properties such as the length of stems and bar lines, thickness
1178 of beams and other lines, and the separation of staff lines all
1179 need to be modified in special ways.
1181 Returning to the ossia example, let us first change the font-size.
1182 We can do this in two ways. We can either change the size of the
1183 fonts of each object type, like @code{NoteHead}s with commands
1187 \override NoteHead #'font-size = #-2
1190 or we can change the size of all fonts by setting a special
1191 property, @code{fontSize}, using @code{\set}, or by including
1192 it in a @code{\with} clause (but without the @code{\set}).
1198 Both of these statements would cause the font size to be reduced
1199 by 2 steps from its previous value, where each
1200 step reduces or increases the size by approximately 12%.
1202 Let's try it in our ossia example:
1204 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1205 \new Staff ="main" {
1212 alignAboveContext = "main"
1213 \override Clef #'stencil = ##f
1214 \override TimeSignature #'stencil = ##f
1215 % Reduce all font sizes by ~24%
1225 This is still not quite right. The note heads and flags are
1226 smaller, but the stems are too long in proportion and the
1227 staff lines are spaced too widely apart. These need to be
1228 scaled down in proportion to the font reduction. The next
1229 sub-section discusses how this is done.
1231 @node Length and thickness of objects
1232 @subsection Length and thickness of objects
1238 @cindex size, changing
1239 @cindex stem length, changing
1240 @cindex staff line spacing, changing
1242 Distances and lengths in LilyPond are generally measured in
1243 staff-spaces, the distance between adjacent lines in the staff,
1244 (or occasionally half staff spaces) while most @code{thickness}
1245 properties are measured in units of an internal property called
1246 @code{line-thickness.} For example, by default, the lines of
1247 hairpins are given a thickness of 1 unit of @code{line-thickness},
1248 while the @code{thickness} of a note stem is 1.3. Note, though,
1249 that some thickness properties are different; for example, the
1250 thickness of beams is measured in staff-spaces.
1252 So how are lengths to be scaled in proportion to the font size?
1253 This can be done with the help of a special function called
1254 @code{magstep} provided for exactly this purpose. It takes
1255 one argument, the change in font size (#-2 in the example above)
1256 and returns a scaling factor suitable for reducing other
1257 objects in proportion. It is used like this:
1259 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1260 \new Staff ="main" {
1267 alignAboveContext = "main"
1268 \override Clef #'stencil = ##f
1269 \override TimeSignature #'stencil = ##f
1271 % Reduce stem length and line spacing to match
1272 \override StaffSymbol #'staff-space = #(magstep -2)
1282 Since the length of stems and many other length-related properties
1283 are always calculated relative to the
1284 value of the @code{staff-space} property these are automatically
1285 scaled down in length too. Note that this affects only the
1286 vertical scale of the ossia -- the horizontal scale is determined
1287 by the layout of the main music in order to remain synchronised
1288 with it, so it is not affected by any of these changes in size.
1289 Of course, if the scale of all the main music were changed in this
1290 way then the horizontal spacing would be affected. This is
1291 discussed later in the layout section.
1293 This, then, completes the creation of an ossia. The sizes and
1294 lengths of all other objects may be modified in analogous ways.
1296 For small changes in scale, as in the example above, the
1297 thickness of the various drawn lines such as bar lines,
1298 beams, hairpins, slurs, etc does not usually require global
1299 adjustment. If the thickness of any particular layout object
1300 needs to be adjusted this can be best achieved by overriding its
1301 @code{thickness} property. An example of changing the thickness
1302 of slurs was shown above in @ref{Properties of layout objects}.
1303 The thickness of all drawn objects (i.e., those not produced
1304 from a font) may be changed in the same way.
1307 @node Placement of objects
1308 @section Placement of objects
1311 * Automatic behaviour::
1312 * Within-staff objects::
1313 * Outside staff objects::
1317 @node Automatic behaviour
1318 @subsection Automatic behaviour
1320 There are some objects in musical notation that belong to
1321 the staff and there are other objects that should be
1322 placed outside the staff. These are called within-staff
1323 objects and outside-staff objects respectively.
1325 Within-staff objects are those that are located on the staff
1326 -- note heads, stems, accidentals, etc. The positions of
1327 these are usually fixed by the music itself -- they are
1328 vertically positioned on specific lines of the staff or are
1329 tied to other objects that are so positioned. Collisions of
1330 note heads, stems and accidentals in closely set chords are
1331 normally avoided automatically. There are commands and
1332 overrides which can modify this automatic behaviour, as we
1335 Objects belonging outside the staff include things such as
1336 rehearsal marks, text and dynamic markings. LilyPond's rule for
1337 the vertical placement of outside-staff objects is to place them
1338 as close to the staff as possible but not so close that they
1339 collide with any other object. LilyPond uses the
1340 @code{outside-staff-priority} property to determine the order in
1341 which the objects should be placed, as follows.
1343 First, LilyPond places all the within-staff objects.
1344 Then it sorts the outside-staff objects according to their
1345 @code{outside-staff-priority}. The outside-staff objects are
1346 taken one by one, beginning with the object with the lowest
1347 @code{outside-staff-priority}, and placed so that they do not
1348 collide with any objects that have already been placed. That is,
1349 if two outside-staff grobs are competing for the same space, the
1350 one with the lower @code{outside-staff-priority} will be placed
1351 closer to the staff. If two objects have the same
1352 @code{outside-staff-priority} the one encountered first will be
1353 placed closer to the staff.
1355 In the following example all the markup texts have the same
1356 priority (since it is not explicity set). Note that @q{Text3}
1357 is automatically positioned close to the staff again, nestling
1360 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1367 Staves are also positioned, by default, as closely together as
1368 possible (subject to a minimum separation). If notes project
1369 a long way towards an adjacent staff they will force the
1370 staves further apart only if an overlap of the notation
1371 would otherwise occur. The following example demonstrates
1372 this @q{nestling} of the notes on adjacent staves:
1374 @lilypond[quote,ragged-right,verbatim]
1377 \relative c' { c a, }
1380 \relative c'''' { c a, }
1386 @node Within-staff objects
1387 @subsection Within-staff objects
1389 We have already seen how the commands @code{\voiceXXX} affect
1390 the direction of slurs, ties, fingering and
1391 everything else which depends on the direction of the stems.
1392 These commands are essential when writing polyphonic music to
1393 permit interweaving melodic lines to be distinguished.
1394 But occasionally it may be necessary to override this automatic
1395 behaviour. This can be done for whole sections of music or even
1396 for an individual note. The property which controls this
1397 behaviour is the @code{direction} property of each layout object.
1398 We first explain what this does, and then introduce a number of
1399 ready-made commands which avoid your having to code explicit
1400 overrides for the more common modifications.
1402 Some layout objects like slurs and ties curve, bend or point
1403 either up or down; others like stems and flags also move to
1404 right or left when they point up or down. This is controlled
1405 automatically when @code{direction} is set.
1407 The following example shows in bar 1 the default behaviour of
1409 with those on high notes pointing down and those on low notes
1410 pointing up, followed by four notes with all stems forced down,
1411 four notes with all stems forced up, and finally four notes
1412 reverted back to the default behaviour.
1414 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1416 \override Stem #'direction = #DOWN
1418 \override Stem #'direction = #UP
1420 \revert Stem #'direction
1424 Here we use the constants @code{DOWN} and @code{UP}.
1425 These have the values @code{-1} and @code{+1} respectively, and
1426 these numerical values may be used instead. The value @code{0}
1427 may also be used in some cases. It is simply treated as meaning
1428 @code{UP} for stems, but for some objects it means @q{center}.
1429 There is a constant, @code{CENTER} which has the value @code{0}.
1431 However, these explicit overrides are not usually used, as there
1432 are simpler equivalent predefined commands available.
1433 Here is a table of the commonest. The meaning of each is stated
1434 where it is not obvious.
1436 @multitable @columnfractions .2 .2 .2 .4
1441 @item @code{\arpeggioDown}
1442 @tab @code{\arpeggioUp}
1443 @tab @code{\arpeggioNeutral}
1444 @tab Arrow is at bottom, at top, or no arrow
1445 @item @code{\dotsDown}
1447 @tab @code{\dotsNeutral}
1448 @tab Direction of movement to avoid staff lines
1449 @item @code{\dynamicDown}
1450 @tab @code{\dynamicUp}
1451 @tab @code{\dynamicNeutral}
1453 @item @code{\phrasingSlurDown}
1454 @tab @code{\phrasingSlurUp}
1455 @tab @code{\phrasingSlurNeutral}
1456 @tab Note: distinct from slur commands
1457 @item @code{\slurDown}
1459 @tab @code{\slurNeutral}
1461 @item @code{\stemDown}
1463 @tab @code{\stemNeutral}
1465 @item @code{\textSpannerDown}
1466 @tab @code{\textSpannerUp}
1467 @tab @code{\textSpannerNeutral}
1468 @tab Text entered as spanner is below/above staff
1469 @item @code{\tieDown}
1471 @tab @code{\tieNeutral}
1473 @item @code{\tupletDown}
1474 @tab @code{\tupletUp}
1475 @tab @code{\tupletNeutral}
1476 @tab Tuplets are below/above notes
1479 Note that these predefined commands may @strong{not} be
1480 preceded by @code{\once}. If you wish to limit the
1481 effect to a single note you must either use the equivalent
1482 @code{\once \override} command or use the predefined command
1483 followed after the affected note by the corresponding
1484 @code{\xxxNeutral} command.
1486 @subheading Fingering
1487 @cindex fingering, placement
1489 The placement of fingering is also affected by the value
1490 of its @code{direction} property, but there are special
1491 commands which allow the fingering of individual notes
1492 of chords to be controlled, with the fingering being placed
1493 above, below, to the left or to the right of each note.
1495 First, here's the effect of @code{direction} on fingering,
1496 the first bar shows the default, then the effect of specifying
1497 @code{DOWN} and @code{UP}:
1499 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1501 \override Fingering #'direction = #DOWN
1503 \override Fingering #'direction = #UP
1507 This is how to control fingering on single notes, but the
1509 property is ignored for chords. Instead, by default, the
1510 fingering is automatically placed both above and below the
1511 notes of a chord, as shown:
1513 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1519 Greater control over the placement of fingering of the
1520 individual notes in a chord is possible by using
1521 the @code{\set fingeringOrientations} command. The format of
1525 @code{\set fingeringOrientations = #'([up] [left/right] [down])}
1529 @code{\set} is used because @code{fingeringOrientations} is a
1530 property of the @code{Voice} context, created and used by the
1531 @code{New_fingering_engraver}.
1533 The property may be set to a list of one to three values.
1534 It controls whether fingerings may be placed above (if
1535 @code{up} appears in the list), below (if @code{down} appears),
1536 to the left (if @code{left} appears, or to the right
1537 (if @code{right} appears). Conversely, if a location is not
1538 listed, no fingering is placed there. LilyPond takes these
1539 contraints and works out the best placement for the fingering
1540 of the notes of the following chords. Note that @code{left} and
1541 @code{right} are mutually exclusive -- fingering may be placed
1542 only on one side or the other, not both.
1544 To control the placement of the fingering of a single note
1545 using this command it is necessary to write it as a single
1546 note chord by placing angle brackets round it.
1548 Here are a few examples:
1550 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1551 \set fingeringOrientations = #'(left)
1553 < c-1 e-2 g-3 b-5 > 4
1554 \set fingeringOrientations = #'(left)
1556 < c-1 e-2 g-3 b-5 > 4
1557 \set fingeringOrientations = #'(up left down)
1559 < c-1 e-2 g-3 b-5 > 4
1560 \set fingeringOrientations = #'(up left)
1562 < c-1 e-2 g-3 b-5 > 4
1563 \set fingeringOrientations = #'(right)
1565 < c-1 e-2 g-3 b-5 > 4
1569 If the fingering seems a little crowded the @code{font-size}
1570 could be reduced. The default value can be seen from the
1571 @code{Fingering} object in the IR to be @code{-5}, so let's
1574 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1575 \override Fingering #'font-size = #-7
1576 \set fingeringOrientations = #'(left)
1578 < c-1 e-2 g-3 b-5 > 4
1579 \set fingeringOrientations = #'(left)
1581 < c-1 e-2 g-3 b-5 > 4
1582 \set fingeringOrientations = #'(up left down)
1584 < c-1 e-2 g-3 b-5 > 4
1585 \set fingeringOrientations = #'(up left)
1587 < c-1 e-2 g-3 b-5 > 4
1588 \set fingeringOrientations = #'(right)
1590 < c-1 e-2 g-3 b-5 > 4
1593 @node Outside staff objects
1594 @subsection Outside staff objects
1596 Outside-staff objects are automatically placed to avoid collisions.
1597 Objects with the lower value of the @code{outside-staff-priority}
1598 property are placed nearer to the staff, and other outside-staff
1599 objects are then raised as far as necessary to avoid collisions.
1600 The @code{outside-staff-priority} is defined in the
1601 @code{grob-interface} and so is a property of all layout objects.
1602 By default it is set to @code{#f} for all within-staff objects,
1603 and to a numerical value appropriate to each outside-staff object
1604 when the object is created. The following table shows
1605 the default numerical values for some of the commonest
1606 outside-staff objects which are, by default, placed in the
1607 @code{Staff} or @code{Voice} contexts.
1609 @multitable @columnfractions .3 .3 .3
1610 @headitem Layout Object
1612 @tab Controls position of:
1613 @item @code{MultiMeasureRestText}
1615 @tab Text over full-bar rests
1616 @item @code{TextScript}
1619 @item @code{OttavaBracket}
1621 @tab Ottava brackets
1622 @item @code{TextSpanner}
1625 @item @code{DynamicLineSpanner}
1627 @tab All dynamic markings
1628 @item @code{VoltaBracketSpanner}
1631 @item @code{TrillSpanner}
1633 @tab Spanning trills
1636 Here is an example showing the default placement of some of
1639 @cindex text spanner
1640 @funindex \startTextSpan
1641 @funindex \stopTextSpan
1642 @cindex ottava bracket
1644 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1645 % Set details for later Text Spanner
1646 \override TextSpanner #'bound-details #'left #'text
1647 = \markup { \small \bold Slower }
1648 % Place dynamics above staff
1650 % Start Ottava Bracket
1655 % Add Dynamic Line Spanner
1661 c\ff c \stopTextSpan
1662 % Stop Ottava Bracket
1667 This example also shows how to create Text Spanners --
1668 text with extender lines above a section of music. The
1669 spanner extends from the @code{\startTextSpan} command to
1670 the @code{\stopTextSpan} command, and the format of the
1671 text is defined by the @code{\override TextSpanner} command.
1672 For more details see @ruser{Text spanners}.
1674 It also shows how ottava brackets are created.
1676 Note that bar numbers, metronome marks and rehearsal marks
1677 are not shown. By default these are created in the
1678 @code{Score} context and their @code{outside-staff-priority}
1679 is ignored relative to the layout objects which are created
1680 in the @code{Staff} context.
1681 If you wish to place bar numbers, metronome marks or rehearsal
1682 marks in accordance with the value of their
1683 @code{outside-staff-priority} the @code{Bar_number_engraver},
1684 @code{Metronome_mark_engraver} or @code{Mark_engraver} respectively
1685 should be removed from the @code{Score} context and placed in the
1686 top @code{Staff} context. If this is done, these marks will be
1687 given the following default @code{outside-staff-priority} values:
1689 @multitable @columnfractions .3 .3
1690 @headitem Layout Object @tab Priority
1691 @item @code{RehearsalMark} @tab @code{1500}
1692 @item @code{MetronomeMark} @tab @code{1000}
1693 @item @code{BarNumber} @tab @code{ 100}
1696 If the default values of @code{outside-staff-priority} do not
1697 give you the placing you want, the priority of any of the objects
1698 may be overridden. Suppose we would
1699 like the ottava bracket to be placed below the text spanner in the
1700 example above. All we need to do is to look up the priority of
1701 @code{OttavaBracket} in the IR or in the tables above, and reduce
1702 it to a value lower than that of a @code{TextSpanner}, remembering
1703 that @code{OttavaBracket} is created in the @code{Staff} context:
1705 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1706 % Set details for later Text Spanner
1707 \override TextSpanner #'bound-details #'left #'text
1708 = \markup { \small \bold Slower }
1709 % Place dynamics above staff
1711 %Place following Ottava Bracket below Text Spanners
1712 \once \override Staff.OttavaBracket #'outside-staff-priority = #340
1713 % Start Ottava Bracket
1718 % Add Dynamic Line Spanner
1724 c\ff c \stopTextSpan
1725 % Stop Ottava Bracket
1730 Changing the @code{outside-staff-priority} can also be used to
1731 control the vertical placement of individual objects, although
1732 the results may not always be desirable. Suppose we would
1733 like @qq{Text3} to be placed above @qq{Text4} in the example
1734 under Automatic behaviour, above (see @ref{Automatic behaviour}).
1735 All we need to do is to look up the priority of @code{TextScript}
1736 in the IR or in the tables above, and increase the priority of
1737 @qq{Text3} to a higher value:
1739 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1742 \once \override TextScript #'outside-staff-priority = #500
1747 This certainly lifts @qq{Text3} above @qq{Text4} but it also
1748 lifts it above @qq{Text2}, and @qq{Text4} now drops down.
1749 Perhaps this is not so good. What we would really like to do
1750 is to position all the annotation at the same distance above
1751 the staff? To do this, we clearly
1752 will need to space the notes out horizontally to make more
1753 room for the text. This is done using the @code{textLengthOn}
1756 @subheading \textLengthOn
1758 @funindex \textLengthOn
1759 @cindex notes, spreading out with text
1761 By default, text produced by markup takes up no horizontal space
1762 as far as laying out the music is concerned. The @code{\textLengthOn}
1763 command reverses this behaviour, causing the notes to be spaced
1764 out as far as is necessary to accommodate the text:
1766 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1767 \textLengthOn % Cause notes to space out to accommodate text
1774 The command to revert to the default behaviour is
1775 @code{\textLengthOff}. Remember @code{\once} only works with
1776 @code{\override}, @code{\set}, @code{\revert} or @code{unset},
1777 so cannot be used with @code{\textLengthOn}.
1779 Markup text will also avoid notes which project above the staff.
1780 If this is not desired, the automatic displacement upwards may
1781 be turned off by setting the priority to @code{#f}. Here's an
1782 example to show how markup text interacts with such notes.
1784 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1785 % This markup is short enough to fit without collision
1789 % This is too long to fit, so it is displaced upwards
1793 % Turn off collision avoidance
1794 \once \override TextScript #'outside-staff-priority = ##f
1798 % Turn off collision avoidance
1799 \once \override TextScript #'outside-staff-priority = ##f
1800 \textLengthOn % and turn on textLengthOn
1801 c,,2^"Long Text " % Spaces at end are honoured
1806 @subheading Dynamics
1808 Dynamic markings will normally be positioned beneath the
1809 staff, but may be positioned above with the @code{dynamicUp}
1810 command. They will be positioned vertically relative to the
1811 note to which they are attached, and will float below (or above)
1812 all within-staff objects such as phrasing slurs and bar numbers.
1813 This can give quite acceptable results, as this example
1816 @lilypond[quote,fragment,ragged-right,verbatim,relative=1]
1821 bes4.~\f\< \( bes4 bes8 des4\ff\> c16 bes\! |
1822 ees,2.~\)\mf ees4 r8 |
1825 However, if the notes and attached dynamics are close
1826 together the automatic placement will avoid collisions
1827 by displacing later dynamic markings further away, but this may
1828 not be the optimum placement, as this rather artificial example
1831 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1837 Should a similar situation arise in @q{real} music, it may
1838 be preferable to space out the notes
1839 a little further, so the dynamic markings can all fit at the
1840 same vertical distance from the staff. We were able to do this
1841 for markup text by using the @code{\textLengthOn} command, but there
1842 is no equivalent command for dynamic marks. So we shall have to
1843 work out how to do this using @code{\override} commands.
1845 @subheading Grob sizing
1848 @cindex sizing grobs
1849 @cindex @code{X-offset}
1850 @cindex @code{Y-offset}
1851 @cindex @code{X-extent}
1852 @cindex @code{Y-extent}
1854 First we must learn how grobs are sized. All grobs have a
1855 reference point defined within them which is used to position
1856 them relative to their parent object. This point in the grob
1857 is then positioned at a horizontal distance, @code{X-offset},
1858 and at a vertical distance, @code{Y-offset}, from its parent.
1859 The horizontal extent of the object is given by a pair of
1860 numbers, @code{X-extent}, which say where the left and right
1861 edges are relative to the reference point. The vertical extent
1862 is similarly defined by a pair of numbers, @code{Y-extent}.
1863 These are properties of all grobs which support the
1864 @code{grob-interface}.
1866 @cindex @code{extra-spacing-width}
1868 By default, outside-staff objects are given a width of zero so
1869 that they may overlap in the horizontal direction. This is done
1870 by the trick of adding infinity to the leftmost extent and
1871 minus infinity to the rightmost extent by setting the
1872 @code{extra-spacing-width} to @code{'(+inf.0 . -inf.0)}. So
1873 to ensure they do not overlap in the horizontal direction we
1874 must override this value of @code{extra-spacing-width} to
1875 @code{'(0 . 0)} so the true width shines through. This is
1876 the command to do this for dynamic text:
1879 \override DynamicText #'extra-spacing-width = #'(0 . 0)
1883 Let's see if this works in our previous example:
1885 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1887 \override DynamicText #'extra-spacing-width = #'(0 . 0)
1892 Well, it has certainly stopped the dynamic marks being
1893 displaced, but two problems remain. The marks should be
1894 spaced a little further apart and it would be better
1895 if they were all the same distance from the staff.
1896 We can solve the first problem easily. Instead of making
1897 the @code{extra-spacing-width} zero we could add a little
1898 more to it. The units are the space between two staff
1899 lines, so moving the left edge half a unit to the left and the
1900 right edge half a unit to the right should do it:
1902 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
1904 % Extend width by 1 staff space
1905 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
1910 This looks better, but maybe we would prefer the dynamic marks
1911 to be aligned along the same baseline rather than going up and
1912 down with the notes. The property to do this is
1913 @code{staff-padding} which is covered in the following section.
1916 @node Collisions of objects
1917 @section Collisions of objects
1921 * Fixing overlapping notation::
1922 * Real music example::
1925 @node Moving objects
1926 @subsection Moving objects
1928 This may come as a surprise, but LilyPond is not perfect. Some
1929 notation elements can overlap. This is unfortunate, but in fact
1930 rather rare. Usually the need to move objects is for clarity or
1931 aesthetic reasons -- they would look better with a little more
1932 or a little less space around them.
1934 There are three main main approaches to resolving overlapping
1935 notation. They should be considered in the following order:
1939 The @strong{direction} of one of the overlapping objects may
1940 be changed using the predefined commands listed above for
1941 within-staff objects (see @ref{Within-staff objects}).
1942 Stems, slurs, beams, ties, dynamics, text and tuplets may be
1943 repositioned easily in this way. The limitation is that you
1944 have a choice of only two positions, and neither may be
1948 The @strong{object properties}, which LilyPond uses
1949 when positioning layout objects, may be modified using
1950 @code{\override}. The advantages
1951 of making changes to this type of property are (a) that some
1952 other objects will be moved automatically if necessary to make
1953 room and (b) the single override can apply to all instances of
1954 the same type of object. Such properties include:
1960 This has already been covered in some detail -- see
1961 @ref{Within-staff objects}.
1964 @code{padding}, @code{left-padding},
1965 @code{right-padding}, @code{staff-padding}
1967 @cindex left-padding property
1968 @cindex padding property
1969 @cindex right-padding property
1970 @cindex staff-padding property
1971 As an object is being positioned the value of its @code{padding}
1972 property specifies the gap that must be left between itself and
1973 the nearest edge of the object against which it is being
1974 positioned. Note that it is the @code{padding} value of the object
1975 @strong{being placed} that is used;
1976 the @code{padding} value of the object which is already placed is
1977 ignored. Gaps specified by @code{padding} can be applied
1978 to all objects which support the @code{side-position-interface}.
1980 Instead of @code{padding}, the placement of groups of accidentals
1981 is controlled by @code{left-padding} and @code{right-padding}.
1982 These properties are to be found in the @code{AccidentalPlacement}
1983 object which, note, lives in the @strong{staff} context. Because
1984 accidentals are always positioned after and to the left of
1985 note heads only the @code{right-padding} property has any effect.
1987 The @code{staff-padding} property is closely related to the
1988 @code{padding} property: @code{padding}
1989 controls the minimum amount of space between any object which
1990 supports the @code{side-position-interface} and the nearest
1991 other object (generally the note or the staff lines);
1992 @code{staff-padding} applies only to those objects which are always
1993 set outside the staff -- it controls the minimum amount of space
1994 that should be inserted between that object and the staff. Note
1995 that @code{staff-padding} has no effect on objects which are
1996 positioned relative to the note rather than the staff, even though
1997 it may be overridden without error for such objects -- it is simply
2000 To discover which padding property is required for the object
2001 you wish to reposition, you
2002 need to return to the IR and look up the object's properties.
2003 Be aware that the padding properties might not be located in the
2004 obvious object, so look in objects that appear to be related.
2006 All padding values are measured in staff spaces. For most
2007 objects, this value is set by default to be around 1.0 or less
2008 (it varies with each object). It may be overridden if a larger
2009 (or smaller) gap is required.
2012 @code{self-alignment-X}
2014 @cindex self-alignment-X property
2015 This property can be used to align the object to the left, to
2016 the right, or to center it with respect to the parent object's
2017 reference point. It may be used with all objects which support
2018 the @code{self-alignment-interface}. In general these are objects
2019 that contain text. The values are @code{LEFT}, @code{RIGHT}
2020 or @code{CENTER}. Alternatively, a numerical value between
2021 @code{-1} and @code{+1} may be specified, where @code{-1} is
2022 left-aligned, @code{+1} is right-aligned, and numbers in between
2023 move the text progressively from left-aligned to right-aligned.
2024 Numerical values greater than @code{1} may be specified to move
2025 the text even further to the left, or less than @code{-1} to
2026 move the text even further to the right. A change of @code{1}
2027 in the value corresponds to a movement of half the text's length.
2030 @code{extra-spacing-width}
2032 @cindex extra-spacing-width property
2033 This property is available for all objects which support the
2034 @code{item-interface}. It takes two numbers, the first is added
2035 to the leftmost extent and the second is added to the rightmost
2036 extent. Negative numbers move the edge to the left, positive to
2037 the right, so to widen an object the first number must be negative,
2038 the second positive. Note that not all objects honour both
2039 numbers. For example, the @code{Accidental} object only takes
2040 notice of the first (left edge) number.
2043 @code{staff-position}
2045 @cindex staff-position property
2046 @code{staff-position} is a property of the
2047 @code{staff-symbol-referencer-interface}, which is supported by
2048 objects which are positioned relative to the staff. It specifies
2049 the vertical position of the object relative to the center line
2050 of the staff in half staff-spaces. It is useful in resolving
2051 collisions between layout objects like multi-measure rests, ties
2052 and notes in different voices.
2057 @cindex force-hshift property
2059 Closely spaced notes in a chord, or notes occuring at the same
2060 time in different voices, are arranged in two, occasionally more,
2061 columns to prevent the note heads overlapping. These are called
2062 note columns, and an object called @code{NoteColumn} is created
2063 to lay out the notes in that column.
2065 The @code{force-hshift}
2066 property is a property of a @code{NoteColumn} (actually of the
2067 @code{note-column-interface}). Changing it permits a note column
2068 to be moved in units appropriate to a note column, viz. the note
2069 head width of the first voice note. It should be used in
2070 complex situations where the normal @code{\shiftOn} commands (see
2071 @ref{Explicitly instantiating voices}) do
2072 not resolve the note conflict. It is preferable to the
2073 @code{extra-offset} property for this purpose as there is no need
2074 to work out the distance in staff-spaces, and moving the notes
2075 into or out of a @code{NoteColumn} affects other actions such as
2080 Objects do not all have all of these properties in general.
2081 It is necessary to go to the IR to look up which properties
2082 are available for the object in question.
2085 Finally, when all else fails, objects may be manually repositioned
2086 relative to the staff center line verically, or by
2087 displacing them by any distance to a new position. The
2088 disadvantages are that the correct values for the repositioning
2089 have to be worked out, often by trial and error, for every object
2090 individually, and, because the movement is done after LilyPond has
2091 placed all other objects, the user is responsible for avoiding any
2092 collisions that might ensue. But the main difficulty with this
2093 approach is that the repositioning values may need to be reworked
2094 if the music is later modified. The properties that can be used
2095 for this type of manual repositioning are:
2099 @cindex extra-offset property
2100 This property applies to any layout object
2101 supporting the @code{grob-interface}. It takes a pair of
2102 numbers which specify the extra displacement in the horizontal and
2103 vertical directions. Negative numbers move the object to
2104 the left or down. The units are staff-spaces. The extra
2105 displacement is made after the typesetting of objects is
2106 finished, so an object may be repositioned anywhere without
2107 affecting anything else.
2110 @cindex positions property
2111 This is most useful for manually adjusting the slope and height
2112 of beams, slurs, and tuplets. It takes a pair of numbers
2113 giving the position of the left and right ends of the beam, slur,
2114 etc. relative to the center line of the staff. Units are
2115 staff-spaces. Note, though, that slurs and phrasing slurs cannot
2116 be repositioned by arbitrarily large amounts. LilyPond first
2117 generates a list of possible positions for the slur and by default
2118 finds the slur that @qq{looks best}. If the @code{positions}
2119 property has been overridden the slur that is closest to the
2120 requested positions is selected from the list.
2123 Objects do not all have all of these properties in general.
2124 It is necessary to go to the IR to look up which properties
2125 are available for the object in question.
2129 Here is a list of the objects which are most likely to be
2130 involved in collisions, together with the name of the object which
2131 should be looked up in the IR in order to discover which properties
2132 should be used to move them.
2134 @multitable @columnfractions .5 .5
2135 @headitem Object type @tab Object name
2136 @item Articulations @tab @code{Script}
2137 @item Beams @tab @code{Beam}
2138 @item Dynamics (vertically) @tab @code{DynamicLineSpanner}
2139 @item Dynamics (horizontally) @tab @code{DynamicText}
2140 @item Fingerings @tab @code{Fingering}
2141 @item Rehearsal / Text marks @tab @code{RehearsalMark}
2142 @item Slurs @tab @code{Slur}
2143 @item Text e.g. @code{^"text"} @tab @code{TextScript}
2144 @item Ties @tab @code{Tie}
2145 @item Tuplets @tab @code{TupletBracket}
2149 @node Fixing overlapping notation
2150 @subsection Fixing overlapping notation
2152 Let's now see how the properties in the previous section can
2153 help to resolve overlapping notation.
2155 @subheading padding property
2156 @cindex padding property
2158 The @code{padding} property can be set to increase
2159 (or decrease) the distance between symbols that are printed
2160 above or below notes.
2162 @lilypond[quote,fragment,relative=1,verbatim]
2164 \override Script #'padding = #3
2168 @lilypond[quote,fragment,relative=1,verbatim]
2169 % This will not work, see below:
2170 \override MetronomeMark #'padding = #3
2174 \override Score.MetronomeMark #'padding = #3
2179 Note in the second example how important it is to figure out what
2180 context handles a certain object. Since the @code{MetronomeMark}
2182 is handled in the @code{Score} context, property changes in the
2183 @code{Voice} context will not be noticed. For more details, see
2184 @ruser{Constructing a tweak}.
2186 If the @code{padding} property of an object is increased when that
2187 object is in a stack of objects being positioned according to
2188 their @code{outside-staff-priority}, then that object and all
2189 objects outside it are moved.
2192 @subheading left-padding and right-padding
2193 @cindex left-padding property
2194 @cindex right-padding property
2196 The @code{right-padding} property affects the spacing between the
2197 accidental and the note to which it applies. It is not often
2198 required, but the following example shows one situation where it
2199 is needed. Suppose we wish to show a chord containing both
2200 a B-natural and a B-flat. To avoid ambiguity we would like to
2201 precede the notes with both a natural and a flat sign. Here
2202 are a few attempts to do this:
2204 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2210 None work, with the second two showing a bad collision between
2213 One way of achieving this is to override the accidental stencil
2214 with a markup containing the natural and flat symbols in the
2215 order we would like, like this:
2217 @lilypond[quote,ragged-right,verbatim]
2218 naturalplusflat = \markup { \natural \flat }
2220 \once \override Accidental
2221 #'stencil = #ly:text-interface::print
2222 \once \override Accidental #'text = #naturalplusflat
2223 \once \override Score.AccidentalPlacement #'right-padding = #1.5
2229 This necessarily uses an override for the accidental stencil which
2230 will not be covered until later. The stencil type must be a
2231 procedure, here changed to print the contents of the @code{text}
2232 property of @code{Accidental}, which itself is set to be a natural
2233 sign followed by a flat sign. These are then moved further away
2234 from the note head by overriding @code{right-padding}.
2238 @subheading staff-padding property
2239 @cindex staff-padding property
2241 @code{staff-padding} can be used to align objects such as dynamics
2242 along a baseline at a fixed height above the staff, rather than
2243 at a height dependent on the position of the note to which they
2244 are attached. It is not a property of
2245 @code{DynamicText} but of @code{DynamicLineSpanner}.
2246 This is because the baseline should apply equally to @strong{all}
2247 dynamics, including those created as extended spanners.
2248 So this is the way to align the dynamic marks in the example
2249 taken from the previous section:
2251 @lilypond[quote,fragment,ragged-right,verbatim,relative=2]
2253 % Extend width by 1 unit
2254 \override DynamicText #'extra-spacing-width = #'(-0.5 . 0.5)
2255 % Align dynamics to a base line 2 units above staff
2256 \override DynamicLineSpanner #'staff-padding = #2
2261 @subheading self-alignment-X property
2262 @cindex self-alignment-X property
2264 The following example shows how this can resolve the collision
2265 of a string fingering object with a note's stem by aligning the
2266 right edge with the reference point of the parent note:
2268 @lilypond[quote,fragment,ragged-right,verbatim,relative=3]
2271 \once \override StringNumber #'self-alignment-X = #RIGHT
2275 @subheading staff-position property
2276 @cindex staff-position property
2278 Multimeasure rests in one voice can collide with notes in another.
2279 Since these rests are typeset centered between the bar lines, it
2280 would require significant effort for LilyPond to figure out which
2281 other notes might collide with it, since all the current collision
2282 handling between notes and between notes and rests is done only
2283 for notes and rests that occur at the same time. Here's an
2284 example of a collision of this type:
2286 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2287 << {c c c c} \\ {R1} >>
2290 The best solution here is to move the multimeasure rest down,
2291 since the rest is in voice two.
2292 The default in @code{\voiceTwo} (i.e. in the second voice of a
2293 @code{<<@{...@} \\ @{...@}>>} construct)
2294 is that @code{staff-position} is set to -4 for MultiMeasureRest,
2295 so we need to move it, say, four half-staff spaces down to
2298 @lilypond[quote,verbatim,fragment,ragged-right, relative=1]
2302 \override MultiMeasureRest #'staff-position = #-8
2307 This is better than using, for example, @code{extra-offset},
2308 because the ledger line above the rest is inserted automatically.
2310 @subheading extra-offset property
2311 @cindex extra-offset property
2313 The @code{extra-offset} property provides complete control over the
2314 positioning of an object both horizontally and vertically.
2316 In the following example, the second fingering is moved a little to
2317 the left, and 1.8 staff space downwards:
2319 @lilypond[quote,fragment,relative=1,verbatim]
2322 \once \override Fingering
2323 #'extra-offset = #'(-0.3 . -1.8)
2328 @subheading positions property
2329 @cindex positions property
2331 The @code{positions} property allows the position and slope of
2332 tuplets, slurs, phrasing slurs and beams to be controlled
2333 manually. Here's an example which has an ugly phrasing slur
2334 due to its trying to avoid the slur on the acciaccatura.
2336 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2337 r4 \acciaccatura e8\( d8 c ~c d c d\)
2341 We could simply move the phrasing slur above the notes, and this
2342 would be the preferred solution:
2344 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2347 \acciaccatura e8\( d8 c ~c d c d\)
2351 but if there were some reason why this could not be done the
2352 other alternative would be to move the left end of the phrasing
2353 slur down a little using the @code{positions} property. This
2354 also resolves the rather nasty shape.
2356 @lilypond[quote,verbatim,fragment,ragged-right,relative=1]
2358 \once \override PhrasingSlur #'positions = #'(-4 . -3)
2360 e8\( d8 c ~c d c d\)
2363 Here's a further example taken from the opening of the left-hand
2364 staff of Chopin's Prelude Op 28 No. 2. We see that the beam
2365 collides with the upper notes:
2367 @lilypond[quote,verbatim,fragment,ragged-right]
2370 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2371 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2376 This can be resolved by manually moving both ends of the beam
2377 up from their position at 2 staff-spaces above the center line to,
2380 @lilypond[quote,verbatim,fragment,ragged-right]
2384 \override Beam #'positions = #'(3 . 3)
2389 << {b,8 ais, b, g,} \\ {e, g e, g} >>
2394 Note that the override continues to apply in the first voice of
2395 the second block of quavers, but not to any of the beams in the
2398 @subheading force-hshift property
2399 @cindex force-hshift property
2400 @c FIXME: formatting stuff (ie not important right now IMO)
2401 @c @a nchor Chopin finally corrected TODOgp
2403 We can now see how to apply the final corrections to the Chopin
2404 example introduced at the end of @ref{I'm hearing Voices}, which
2405 was left looking like this:
2407 @lilypond[quote,verbatim,fragment,ragged-right]
2408 \new Staff \relative c'' {
2411 { c2 aes4. bes8 } \\
2423 The lower two notes of the first chord (i.e,
2424 those in the third voice) should not be shifted away from the
2425 note column of the higher two notes. To correct this we set
2426 @code{force-hshift}, which is a property of
2427 @code{NoteColumn}, of these notes to zero.
2428 The lower note of the second chord is best placed just to the
2429 right of the higher notes. We achieve this by setting
2430 @code{force-hshift} of this note to 0.5, ie half a note head's
2431 width to the right of the note column of the higher notes.
2433 Here's the final result:
2435 @lilypond[quote,verbatim,fragment,ragged-right]
2436 \new Staff \relative c'' {
2439 { c2 aes4. bes8 } \\
2442 \once \override NoteColumn #'force-hshift = #0 <ees c>2
2443 \once \override NoteColumn #'force-hshift = #0.5 des2
2451 @node Real music example
2452 @subsection Real music example
2454 We end this section on Tweaks by showing the steps to be taken to
2455 deal with a tricky example which needs several tweaks to produce
2456 the desired output. The example has been deliberately chosen to
2457 illustrate the use of the Notation Reference to resolve unusual
2458 problems with notation. It is not representative of more usual
2459 engraving process, so please do not let these difficulties put
2460 you off! Fortunately, difficulties like these are not very common!
2462 The example is from Chopin's Première Ballade, Op. 23, bars 6 to
2463 9, the transition from the opening Lento to Moderato.
2464 Here, first, is what we want the output to look like, but to avoid
2465 over-complicating the example too much we have left out the
2466 dynamics, fingering and pedalling.
2468 @c The following should appear as music without code
2469 @lilypond[quote,ragged-right]
2470 rhMusic = \relative c'' {
2473 \once \override Tie #'staff-position = #3.5
2477 \override Staff.NoteCollision #'merge-differently-headed = ##t
2478 \override Staff.NoteCollision #'merge-differently-dotted = ##t
2479 bes2.^\markup {\bold "Moderato"} r8
2481 {c,8[ d fis bes a] | }
2483 % Reposition the c2 to the right of the merged note
2484 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
2485 % Move the c2 out of the main note column so the merge will work
2488 % Stem on the d2 must be down to permit merging
2489 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
2493 \revert Staff.NoteCollision #'merge-differently-headed
2494 \revert Staff.NoteCollision #'merge-differently-dotted
2498 lhMusic = \relative c' {
2500 <d g, d>1)\arpeggio |
2507 \new Staff = "RH" <<
2511 \new Staff = "LH" <<
2520 We note first that the right hand part in the third bar
2521 requires four voices. These are the five beamed eighth notes,
2522 the tied C, the half-note D which is merged with the eighth note
2523 D, and the dotted quarter note F-sharp, which is also merged with
2524 the eighth note at the same pitch. Everything else is in a single
2525 voice, so the easiest way is to introduce these four voices
2526 temporarily at the time they are needed. If you have forgotten
2527 how to do this, look at @ref{I'm hearing Voices}. Let us begin
2528 by entering the notes as two variables and setting up the staff
2529 structure in a score block, and see what LilyPond produces by
2532 @lilypond[quote,verbatim,ragged-right]
2533 rhMusic = \relative c'' {
2538 % Start polyphonic section of four voices
2540 {c,8 d fis bes a | }
2551 lhMusic = \relative c' {
2560 \new Staff = "RH" <<
2564 \new Staff = "LH" <<
2573 All the notes are right, but the appearance is far from
2574 satisfactory. The tie clashes with the change in time signature,
2575 the beaming in the third bar is wrong, the notes are not
2576 merged together, and several notation elements are missing.
2577 Let's first deal with the easier things.
2578 We can correct the beaming by inserting a beam
2579 manually, and we can easily add the left hand slur and the right
2580 hand phrasing slur, since these were all covered in the Tutorial.
2583 @lilypond[quote,verbatim,ragged-right]
2584 rhMusic = \relative c'' {
2589 % Start polyphonic section of four voices
2591 {c,8[ d fis bes a] | }
2602 lhMusic = \relative c' {
2611 \new Staff = "RH" <<
2615 \new Staff = "LH" <<
2624 The first bar is now correct. The second bar contains an arpeggio
2625 and is terminated by a double bar line. How do we do these, as they
2626 have not been mentioned in this Learning Manual? This is where
2627 we need to turn to the Notation Reference. Looking up @q{arpeggio}
2628 and @q{bar line} in the
2629 index quickly shows us that an arpeggio is produced by appending
2630 @code{\arpeggio} to a chord, and a double bar line is produced by
2631 the @code{\bar "||"} command. That's easily done. We next need
2632 to correct the collision of the tie with the time signature. This
2633 is best done by moving the tie upwards. Moving objects was covered
2634 earlier in @ref{Moving objects}, which says that objects positioned
2635 relative to the staff can be moved by overriding their
2636 @code{staff-position} property, which is specified in half staff
2637 spaces relative to the center line of the staff. So the following
2638 override placed just before the first tied note would move the tie
2639 up to 3.5 half staff spaces above the center line:
2641 @code{\once \override Tie #'staff-position = #3.5}
2643 This completes bar two, giving:
2645 @lilypond[quote,verbatim,ragged-right]
2646 rhMusic = \relative c'' {
2648 \once \override Tie #'staff-position = #3.5
2653 % Start polyphonic section of four voices
2655 {c,8[ d fis bes a] | }
2666 lhMusic = \relative c' {
2668 <d g, d>1)\arpeggio |
2675 \new Staff = "RH" <<
2679 \new Staff = "LH" <<
2688 On to bar three and the start of the Moderato section. The
2689 tutorial showed how to add embolded text with the
2690 @code{\markup} command, so adding @q{Moderato} in bold is easy.
2691 But how do we merge notes in different voices together? The
2692 index in the Notation Reference does not mention merging,
2693 but a search of the text for @q{merge} quickly leads us to
2694 the overrides for merging differently headed and differently
2695 dotted notes in @ruser{Collision Resolution}. In our
2696 example we need to merge both types of note for the duration
2697 of the polyphonic section in bar 3, so using the information
2698 in the Notation Reference we add
2701 \override Staff.NoteCollision #'merge-differently-headed = ##t
2702 \override Staff.NoteCollision #'merge-differently-dotted = ##t
2706 to the start of that section and
2709 \revert Staff.NoteCollision #'merge-differently-headed
2710 \revert Staff.NoteCollision #'merge-differently-dotted
2716 @lilypond[quote,verbatim,ragged-right]
2717 rhMusic = \relative c'' {
2719 \once \override Tie #'staff-position = #3.5
2723 bes2.^\markup {\bold "Moderato"} r8
2724 \override Staff.NoteCollision #'merge-differently-headed = ##t
2725 \override Staff.NoteCollision #'merge-differently-dotted = ##t
2726 % Start polyphonic section of four voices
2728 {c,8[ d fis bes a] | }
2736 \revert Staff.NoteCollision #'merge-differently-headed
2737 \revert Staff.NoteCollision #'merge-differently-dotted
2741 lhMusic = \relative c' {
2743 <d g, d>1)\arpeggio |
2750 \new Staff = "RH" <<
2754 \new Staff = "LH" <<
2763 These overrides have merged the two F-sharp notes, but not the two
2764 on D. Why not? The answer is there in the same section in the
2765 Notation Reference -- notes being merged must have stems in
2766 opposite directions and two notes cannot be merged successfully if
2767 there is a third note in the same note column. Here the two D's
2768 both have upward stems and there is a third note -- the C. We know
2769 how to change the stem direction using @code{\stemDown}, and
2770 the Notation Reference also says how to move the C -- apply a shift
2771 using one of the @code{\shift} commands. But which one?
2772 The C is in voice two which has shift off, and the two D's are in
2773 voices one and three, which have shift off and shift on,
2774 respectively. So we have to shift the C a further level still
2775 using @code{\shiftOnn} to avoid it interferring with the two D's.
2776 Applying these changes gives:
2778 @lilypond[quote,verbatim,ragged-right]
2779 rhMusic = \relative c'' {
2781 \once \override Tie #'staff-position = #3.5
2785 bes2.^\markup {\bold "Moderato"} r8
2786 \override Staff.NoteCollision #'merge-differently-headed = ##t
2787 \override Staff.NoteCollision #'merge-differently-dotted = ##t
2788 % Start polyphonic section of four voices
2790 {c,8[ d fis bes a] | }
2792 % Move the c2 out of the main note column so the merge will work
2793 {c,8~ \shiftOnn c2 | }
2795 % Stem on the d2 must be down to permit merging
2796 {s8 \stemDown d2 | }
2800 \revert Staff.NoteCollision #'merge-differently-headed
2801 \revert Staff.NoteCollision #'merge-differently-dotted
2805 lhMusic = \relative c' {
2807 <d g, d>1)\arpeggio |
2814 \new Staff = "RH" <<
2818 \new Staff = "LH" <<
2827 Nearly there. Only two problems remain: The downward stem on the
2828 merged D should not be there, and the C would be better positioned
2829 to the right of the D's. We know how to do both of these from the
2830 earlier tweaks: we make the stem transparent, and move the C with
2831 the @code{force-hshift} property. Here's the final result:
2833 @lilypond[quote,verbatim,ragged-right]
2834 rhMusic = \relative c'' {
2837 \once \override Tie #'staff-position = #3.5
2841 bes2.^\markup {\bold "Moderato"} r8
2842 \override Staff.NoteCollision #'merge-differently-headed = ##t
2843 \override Staff.NoteCollision #'merge-differently-dotted = ##t
2845 {c,8[ d fis bes a] | }
2847 % Reposition the c2 to the right of the merged note
2848 {c,8~ \once \override NoteColumn #'force-hshift = #1.0
2849 % Move the c2 out of the main note column so the merge will work
2852 % Stem on the d2 must be down to permit merging
2853 {s8 \stemDown \once \override Stem #'transparent = ##t d2}
2857 \revert Staff.NoteCollision #'merge-differently-headed
2858 \revert Staff.NoteCollision #'merge-differently-dotted
2862 lhMusic = \relative c' {
2864 <d g, d>1)\arpeggio |
2871 \new Staff = "RH" <<
2875 \new Staff = "LH" <<
2885 @node Further tweaking
2886 @section Further tweaking
2889 * Other uses for tweaks::
2890 * Using variables for tweaks::
2891 * Other sources of information::
2892 * Avoiding tweaks with slower processing::
2893 * Advanced tweaks with Scheme::
2896 @node Other uses for tweaks
2897 @subsection Other uses for tweaks
2901 @cindex transparent property, use of
2902 @cindex objects, making invisible
2903 @cindex removing objects
2904 @cindex objects, removing
2905 @cindex hiding objects
2906 @cindex invisible objects
2907 @cindex tying notes across voices
2910 @subheading Tying notes across voices
2912 The following example demonstrates how to connect notes in
2913 different voices using ties. Normally, only two notes in the
2914 same voice can be connected with ties. By using two voices,
2915 with the tied notes in one of them
2917 @lilypond[quote,fragment,relative=2]
2918 << { b8~ b8\noBeam }
2924 and blanking the first up-stem in that voice, the tie appears to
2927 @lilypond[quote,fragment,relative=2,verbatim]
2930 \once \override Stem #'transparent = ##t
2938 To make sure that the just-blanked stem doesn't squeeze the tie
2939 too much, we can lengthen the stem by setting the
2940 @code{length} to @code{8},
2942 @lilypond[quote,fragment,relative=2,verbatim]
2945 \once \override Stem #'transparent = ##t
2946 \once \override Stem #'length = #8
2955 @subheading Simulating a fermata
2957 @cindex stencil property, use of
2958 @cindex fermata, implementing in MIDI
2960 For outside-staff objects it is usually better to override the
2961 object's @code{stencil} property rather than its @code{transparent}
2962 property when you wish to remove it from the printed output.
2963 Setting the @code{stencil} property of an object to @code{#f} will
2964 remove that object entirely from the printed output. This means it
2965 has no effect on the placement of other objects placed relative to
2968 For example, if we wished to change the metronome setting in order
2969 to simulate a fermata in the MIDI output we would not want the
2970 metronome markings to appear in the printed output, and we would
2971 not want it to influence the spacing between the two systems or
2972 the spacing of the notes on the staff. So setting its
2973 @code{stencil} property to @code{#f} would be the best way.
2974 We show here the effect of the two methods:
2976 @lilypond[quote,verbatim,ragged-right]
2979 % Visible tempo marking
2982 \once \override Score.MetronomeMark #'transparent = ##t
2983 % Invisible tempo marking to lengthen fermata note in MIDI
2986 \once \override Score.MetronomeMark #'stencil = ##f
2987 % Invisible tempo marking to restore tempo in MIDI
2997 Both methods remove the metronome mark from the printed output,
2998 and both affect the MIDI timing as required, but the first
2999 (transparent) metronome mark still influences the note spacing
3000 while the second (with no stencil) does not.
3004 @node Using variables for tweaks
3005 @subsection Using variables for tweaks
3007 Override commands are often long and tedious to type, and they
3008 have to be absolutely correct. If the same overrides are to be
3009 used many times it may be worth defining variables to hold them.
3010 Suppose we wish to emphasize certain words in lyrics by printing
3011 them in bold italics. The @code{\italic} and @code{\bold}
3012 commands do not work within lyrics so we must instead use the
3013 following @code{\override} and @code{\revert} commands:
3016 @code{\override Lyrics . LyricText #'font-shape = #'italic}
3017 @code{\override Lyrics . LyricText #'font-series = #'bold}
3019 @code{\revert Lyrics . LyricText #'font-shape}
3020 @code{\revert Lyrics . LyricText #'font-series}
3023 These would be extremely tedious to enter if there were many words
3024 requiring emphasis. So instead we define these as two variables,
3025 and use them as follows:
3027 @lilypond[quote,verbatim]
3029 \override Lyrics . LyricText #'font-shape = #'italic
3030 \override Lyrics . LyricText #'font-series = #'bold
3033 \revert Lyrics . LyricText #'font-shape
3034 \revert Lyrics . LyricText #'font-series
3037 global = { \time 4/4 \partial 4 \key c \major}
3038 SopMusic = \relative c' { c4 | e4. e8 g4 g | a a g }
3039 AltoMusic = \relative c' { c4 | c4. c8 e4 e | f f e }
3040 TenorMusic = \relative c { e4 | g4. g8 c4. b8 | a8 b c d e4 }
3041 BassMusic = \relative c { c4 | c4. c8 c4 c | f8 g a b c4 }
3042 VerseOne = \lyrics { E -- | ter -- nal \emph Fa -- ther, \norm | strong to save, }
3043 VerseTwo = \lyricmode { O | \emph Christ, \norm whose voice the | wa -- ters heard, }
3044 VerseThree = \lyricmode { O | \emph Ho -- ly Spi -- rit, \norm | who didst brood }
3045 VerseFour = \lyricmode { O | \emph Tri -- ni -- ty \norm of | love and pow'r }
3051 \new Voice = "Sop" { \voiceOne \global \SopMusic }
3052 \new Voice = "Alto" { \voiceTwo \AltoMusic }
3053 \new Lyrics \lyricsto "Sop" { \VerseOne }
3054 \new Lyrics \lyricsto "Sop" { \VerseTwo }
3055 \new Lyrics \lyricsto "Sop" { \VerseThree }
3056 \new Lyrics \lyricsto "Sop" { \VerseFour }
3060 \new Voice = "Tenor" { \voiceOne \TenorMusic }
3061 \new Voice = "Bass" { \voiceTwo \BassMusic }
3069 @node Other sources of information
3070 @subsection Other sources of information
3072 The Internals Reference documentation contains a lot of information
3073 about LilyPond, but even more information can be gathered by
3074 looking at the internal LilyPond files. To explore these, first
3075 find the directory appropriate to your system, as follows:
3083 @file{@var{installdir}/lilypond/usr/share/lilypond/current/}
3089 @file{@var{installdir}/LilyPond.app/Contents/Resources/share/lilypond/current/}
3090 by either @code{cd}-ing into this directory from the
3091 Terminal, or control-clicking on the LilyPond application and
3092 selecting @q{Show Package Contents}.
3097 Using Windows Explorer, navigate to
3098 @file{@var{installdir}/LilyPond/usr/share/lilypond/current/}
3102 Within this directory the two interesting subdirectories are
3106 @item @file{../ly/ } - contains files in LilyPond format
3108 @item @file{../scm/} - contains files in Scheme format
3112 Let's begin by looking at some files in @file{../ly/}.
3113 Open @file{../ly/property-init.ly} in a text editor. The one
3114 you normally use for @code{.ly} files will be fine. This file
3115 contains the definitions of all the standard LilyPond built-in
3116 commands, such as @code{\stemUp} and @code{\slurDotted}. You will
3117 see that these are nothing more than definitions of variables
3118 containing one or a group of @code{\override} commands. For
3119 example, @code{/tieDotted} is defined to be:
3123 \override Tie #'dash-period = #0.75
3124 \override Tie #'dash-fraction = #0.1
3128 If you do not like the default values these built-in commands can
3129 be redefined easily, just like any other variable, at the
3130 head of your input file.
3132 The following are the most useful files to be found in
3135 @multitable @columnfractions .4 .6
3138 @item @file{../ly/engraver-init.ly}
3139 @tab Definitions of engraver Contexts
3140 @item @file{../ly/paper-defaults.ly}
3141 @tab Specifications of paper-related defaults
3142 @item @file{../ly/performer-init.ly}
3143 @tab Definitions of performer Contexts
3144 @item @file{../ly/property-init.ly}
3145 @tab Definitions of all common built-in commands
3148 Other settings (such as the definitions of markup commands) are
3149 stored as @code{.scm} (Scheme) files. The Scheme programming
3150 language is used to provide a programmable interface into
3151 LilyPond internal operation. Further explanation of these files
3152 is currently outside the scope of this manual, as a knowledge of
3153 the Scheme language is required. Users should be warned that
3154 a substantial amount of technical knowledge or time is required
3155 to understand Scheme and these files (see @ref{Scheme tutorial}).
3157 If you have this knowledge, the Scheme files which may be of
3160 @multitable @columnfractions .4 .6
3163 @item @file{../scm/auto-beam.scm}
3164 @tab Sub-beaming defaults
3165 @item @file{../scm/define-grobs.scm}
3166 @tab Default settings for grob properties
3167 @item @file{../scm/define-markup-commands.scm}
3168 @tab Specify all markup commands
3169 @item @file{../scm/midi.scm}
3170 @tab Default settings for MIDI output
3171 @item @file{../scm/output-lib.scm}
3172 @tab Settings that affect appearance of frets, colors,
3173 accidentals, bar lines, etc
3174 @item @file{../scm/parser-clef.scm}
3175 @tab Definitions of supported clefs
3176 @item @file{../scm/script.scm}
3177 @tab Default settings for articulations
3182 @node Avoiding tweaks with slower processing
3183 @subsection Avoiding tweaks with slower processing
3185 LilyPond can perform extra checks while it processes files. These
3186 checks will take extra time to perform, but fewer manual tweaks
3187 may be required to obtain an acceptable result. If a text script
3188 or part of the lyrics extends over the margins these checks will
3189 compress that line of the score just enough to fit within the
3192 To be effective under all circumstances these checks must be enabled
3193 by placing the overrides in a Score @code{\with} block, rather than
3194 in-line in music, as follows:
3198 % Makes sure text scripts and lyrics are within the paper margins
3199 \override PaperColumn #'keep-inside-line = ##t
3200 \override NonMusicalPaperColumn #'keep-inside-line = ##t
3206 @node Advanced tweaks with Scheme
3207 @subsection Advanced tweaks with Scheme
3209 Although many things are possible with the @code{\override} and
3210 @code{\tweak} commands, an even more powerful way of modifying
3211 the action of LilyPond is available through a programmable
3212 interface to the LilyPond internal operation. Functions are
3213 provided which enable the user to incorporate Scheme code directly
3214 in the internal operation of LilyPond. For example, it is
3215 possible to parametrize an override command which is used often
3216 but with different values.
3218 As the use of these functions require code to be written in the
3219 Scheme programming language, at least a basic knowledge of
3220 programming in Scheme is required. An introduction to this is
3221 provided in the @ref{Scheme tutorial}, and examples showing the
3222 use of these programmable interfaces can be found in
3223 @ref{Tweaking with Scheme}.