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5.6.3 Real music example
We end this section on Tweaks by showing the steps to be taken to deal with a tricky example which needs several tweaks to produce the desired output. The example has been deliberately chosen to illustrate the use of the Notation Reference to resolve unusual problems with notation. It is not representative of the more usual engraving process, so please do not let these difficulties put you off! Fortunately, difficulties like these are not very common!
The example is from Chopin’s Première Ballade, Op. 23, bars 6 to 9, the transition from the opening Lento to Moderato. Here, first, is what we want the output to look like, but to avoid over-complicating the example too much we have left out the dynamics, fingering and pedalling.
![[image of music]](../47/lily-bb73f8d6.png)
We note first that the right hand part in the third bar requires four voices. These are the five beamed eighth notes, the tied C, the half-note D which is merged with the eighth note D, and the dotted quarter note F-sharp, which is also merged with the eighth note at the same pitch. Everything else is in a single voice, so the easiest way is to introduce these extra three voices temporarily at the time they are needed. If you have forgotten how to do this, look at I’m hearing Voices and Explicitly instantiating voices. Here we choose to use explicitly instantiated voices for the polyphonic passage, as LilyPond is better able to avoid collisions if all voices are instantiated explicitly in this way.
So let us begin by entering the notes as two variables, setting up the staff structure in a score block, and seeing what LilyPond produces by default:
rhMusic = \relative { \new Voice { r2 c''4. g8 | bes1~ | \time 6/4 bes2. r8 % Start polyphonic section of four voices << { c,8 d fis bes a } % continuation of main voice \new Voice { \voiceTwo c,8~ 2 } \new Voice { \voiceThree s8 d2 } \new Voice { \voiceFour s4 fis4. } >> | g2. % continuation of main voice } } lhMusic = \relative { r2 <c' g ees>2 | <d g, d>1 | r2. d,,4 r4 r | r4 } \score { \new PianoStaff << \new Staff = "RH" << \key g \minor \rhMusic >> \new Staff = "LH" << \key g \minor \clef "bass" \lhMusic >> >> }
![[image of music]](../2d/lily-3ebcd93d.png)
All the notes are right, but the appearance is far from satisfactory. The tie collides with the change in time signature, some notes are not merged together, and several notation elements are missing. Let’s first deal with the easier things. We can easily add the left hand slur and the right hand phrasing slur, since these were all covered in the Tutorial. Doing this gives:
rhMusic = \relative { \new Voice { r2 c''4.\( g8 | bes1~ | \time 6/4 bes2. r8 % Start polyphonic section of four voices << { c,8 d fis bes a } % continuation of main voice \new Voice { \voiceTwo c,8~ 2 } \new Voice { \voiceThree s8 d2 } \new Voice { \voiceFour s4 fis4. } >> | g2.\) % continuation of main voice } } lhMusic = \relative { r2 <c' g ees>2( | <d g, d>1) | r2. d,,4 r4 r | r4 } \score { \new PianoStaff << \new Staff = "RH" << \key g \minor \rhMusic >> \new Staff = "LH" << \key g \minor \clef "bass" \lhMusic >> >> }
![[image of music]](../16/lily-ec7f1c19.png)
The first bar is now correct. The second bar contains an arpeggio and
is terminated by a double bar line. How do we do these, as they have
not been mentioned in this Learning Manual? This is where we need to
turn to the Notation Reference. Looking up ‘arpeggio’ and ‘bar
line’ in the index quickly shows us that an arpeggio is produced by
appending \arpeggio to a chord, and a double bar line is
produced by the \bar "||" command. That’s easily done. We
next need to correct the collision of the tie with the time signature.
This is best done by moving the tie upwards. Moving objects was
covered earlier in Moving objects, which says that objects
positioned relative to the staff can be moved vertically by overriding
their staff-position property, which is specified in half staff
spaces relative to the center line of the staff. So the following
override placed just before the first tied note would move the tie up
to 3.5 half staff spaces above the center line:
\once \override Tie.staff-position = #3.5
This completes bar two, giving:
rhMusic = \relative { \new Voice { r2 c''4.\( g8 | \once \override Tie.staff-position = #3.5 bes1~ | \bar "||" \time 6/4 bes2. r8 % Start polyphonic section of four voices << { c,8 d fis bes a } % continuation of main voice \new Voice { \voiceTwo c,8~ 2 } \new Voice { \voiceThree s8 d2 } \new Voice { \voiceFour s4 fis4. } >> | g2.\) % continuation of main voice } } lhMusic = \relative { r2 <c' g ees>2( | <d g, d>1)\arpeggio | r2. d,,4 r4 r | r4 } \score { \new PianoStaff << \new Staff = "RH" << \key g \minor \rhMusic >> \new Staff = "LH" << \key g \minor \clef "bass" \lhMusic >> >> }
![[image of music]](../87/lily-9fd63a15.png)
On to bar three and the start of the Moderato section. The tutorial
showed how to add a tempo indication with the \tempo command, so
adding “Moderato” is easy. But how do we merge notes in
different voices together? This is where we need to turn again to
the Notation Reference for help. A search for “merge” in the
Notation Reference index quickly leads us to the commands for merging
differently headed and differently dotted notes in
Collision resolution. In our example we need to merge both
types of note for the duration of the polyphonic section in bar 3,
so using the information we find in the Notation Reference we add
\mergeDifferentlyHeadedOn \mergeDifferentlyDottedOn
to the start of that section and
\mergeDifferentlyHeadedOff \mergeDifferentlyDottedOff
to the end, giving:
![[image of music]](../3e/lily-115dea38.png)
These overrides have merged the two F-sharp notes, but not the two
on D. Why not? The answer is there in the same section in the
Notation Reference – notes being merged must have stems in
opposite directions and two notes cannot be merged successfully if
there is a third note in the same note column. Here the two D’s
both have upward stems and there is a third note – the C. We know
how to change the stem direction using \stemDown, and
the Notation Reference also says how to move the C – apply a shift
using one of the \shift commands. But which one?
The C is in voice two which has shift off, and the two D’s are in
voices one and three, which have shift off and shift on,
respectively. So we have to shift the C a further level still
using \shiftOnn to avoid it interfering with the two D’s.
Applying these changes gives:
rhMusic = \relative { \new Voice { r2 c''4.\( g8 | \once \override Tie.staff-position = #3.5 bes1~ | \bar "||" \time 6/4 bes2.\tempo "Moderato" r8 \mergeDifferentlyHeadedOn \mergeDifferentlyDottedOn % Start polyphonic section of four voices << { c,8 d fis bes a } % continuation of main voice \new Voice { \voiceTwo % Move the c2 out of the main note column % so the merge will work c,8~ \shiftOnn c2 } \new Voice { \voiceThree % Stem on the d2 must be down to permit merging s8 \stemDown d2 } \new Voice { \voiceFour s4 fis4. } >> | \mergeDifferentlyHeadedOff \mergeDifferentlyDottedOff g2.\) % continuation of main voice } } lhMusic = \relative { r2 <c' g ees>2( | <d g, d>1)\arpeggio | r2. d,,4 r4 r | r4 } \score { \new PianoStaff << \new Staff = "RH" << \key g \minor \rhMusic >> \new Staff = "LH" << \key g \minor \clef "bass" \lhMusic >> >> }
![[image of music]](../19/lily-5dc9ba5e.png)
Nearly there. Only two problems remain: The downward stem on the
merged D should not be there, and the C would be better positioned
to the right of the D’s. We know how to do both of these from the
earlier tweaks: we make the stem transparent, and move the C with
the force-hshift property. Here’s the final result:
rhMusic = \relative { \new Voice { r2 c''4.\( g8 | \once \override Tie.staff-position = #3.5 bes1~ | \bar "||" \time 6/4 bes2.\tempo "Moderato" r8 \mergeDifferentlyHeadedOn \mergeDifferentlyDottedOn % Start polyphonic section of four voices << { c,8 d fis bes a } % continuation of main voice \new Voice { \voiceTwo c,8~ % Reposition the c2 to the right of the merged note \once \override NoteColumn.force-hshift = #1.0 % Move the c2 out of the main note column % so the merge will work \shiftOnn c2 } \new Voice { \voiceThree s8 % Stem on the d2 must be down to permit merging \stemDown % Stem on the d2 should be invisible \tweak Stem.transparent ##t d2 } \new Voice { \voiceFour s4 fis4. } >> | \mergeDifferentlyHeadedOff \mergeDifferentlyDottedOff g2.\) % continuation of main voice } } lhMusic = \relative { r2 <c' g ees>2( | <d g, d>1)\arpeggio | r2. d,,4 r4 r | r4 } \score { \new PianoStaff << \new Staff = "RH" << \key g \minor \rhMusic >> \new Staff = "LH" << \key g \minor \clef "bass" \lhMusic >> >> }
![[image of music]](../ff/lily-9f5380d5.png)
| [ << Tweaking output ] | [首页][目录][索引] | [ Templates >> ] |
| [ < The force-hshift property ] | [ 上 : Collisions of objects ] | [ Further tweaking > ] |