1 \input texinfo @c -*-texinfo-*- vim:tw=72
2 @setfilename regression-test.info
3 @settitle LilyPond Regression test
7 @author Han-Wen Nienhuys and Jan Nieuwenhuizen
8 @title LilyPond Regression test
15 This document tries give a brief overview of LilyPond features. When
16 the text correspond with the shown notation, we consider LilyPond
17 Officially BugFree (tm). This document is intended for finding bugs,
18 and documenting bugfixes.
20 [TODO: revise and completize this. ]
22 [TODO: should generate out of header fields using ly2dvi?]
26 @section Notes and rests
28 Rests. Note that the dot of 8th, 16th and 32nd rests rest should be
29 next to the top of the rest. All rests except the whole rest are
30 centered on the middle staff line.
34 Note head shapes are settable. The stem endings should be adjusted
35 per note head. If you want different note head styles on one stem,
36 you must create a special context called Thread.
38 Harmonic notes have a different shape and different
39 dimensions. Nevertheless, noteheads in both styles can be combined, on
40 either up or down stems.
42 @mudelafile{noteheadstyle.ly}
44 Noteheads can have dots, and rests can too. Augmentation dots should
45 never be printed on a staff line, but rather be shifted vertically. They
46 should go up, but in case of multiple parts, the down stems have down
47 shifted dots. (Wanske p. 186) In case of chords, all dots should be in
48 a column. The dots go along as rests are shifted to avoid collisions.
52 Accidentals work: the second note does not get a sharp. The third and
53 fourth show forced and courtesy accidentals
55 @mudelafile{accidental.ly}
57 Multiple measure rests do not collide with barlines and clefs. They
58 are not expanded when you set @code{Score.skipBars}. Although the
59 multi-measure-rest is a Spanner, minimum distances are set to keep it
60 colliding from barlines.
63 @mudelafile{multi-measure-rest.ly}
65 If @code{Score.skipBars} is set,
66 the signs for four, two, and one measure rest are combined to
67 produce the graphical representation of rests for up to 10 bars.
68 The number of bars will be written above the sign.
70 @mudelafile{mm-rests2.ly}
72 A sharp sign after a double sharp sign, as well as a flat sign
73 after a double flat sign is automatically prepended with a
76 @mudelafile{accidental-single-double.ly}
80 Stem tremolos or rolls are tremolo signs that look like beam segments
81 crossing stems. If the stem is in a beam, the tremolo must be parallel
82 to the beam. If the stem is invisible (eg. on a whole note), the
83 tremolo must be centered on the note.
85 @mudelafile{stem-tremolo.ly}
87 Chord tremolos look like beams, but are a kind of repeat symbol.
88 To avoid confusion, chord tremolo beams do not reach the stems, but
89 leave a gap. Chord tremolo beams on half notes are not ambiguous,
90 as half notes cannot appear in a regular beam, and should reach the
93 @mudelafile{chord-tremolo.ly}
95 Beams, stems and noteheads often have communication troubles, since
96 the two systems for y dimensions (1 unit = staffspace, 1 unit = 1
99 Stems, beams, ties and slurs should behave similarly, when placed
100 on the middle staff line. Of course stem-direction is down for high
101 notes, and up for low notes.
103 @mudelafile{stem-direction.ly}
105 Similarly, if @code{stem_default_neutral_direction} is set to @code{-1}.
107 @mudelafile{stem-direction-down.ly}
111 The staccato dot (and all scripts with follow-into-staff set), must
112 not be on staff lines.
114 @mudelafile{staccato-pos.ly}
116 Dynamics appear below or above the staff. If multiple dynamics are
117 linked with (de)crescendi, they should be on the same line.
119 @mudelafile{dyn-line.ly}
123 Chord names are generated from a list pitches, and are customisable
124 from guile. For some unlogical names, guile customisation is used
127 @mudelafile{chord-names.ly}
131 Grace notes are typeset as an encapsulated piece of music. You can
132 have beams, notes, chords, stems etc. within a @code{\grace} section.
133 Slurs that start within a grace section, but aren't ended are attached
134 to the next normal note. Grace notes have zero duration. If there
135 are tuplets, the grace notes won't be under the brace. Grace notes
136 can have accidentals, but they are (currently) spaced at a fixed
137 distance. Grace notes (of course) come before the accidentals of the
138 main note. Grace notes can also be positioned after the main note.
140 Grace notes without beams should have a slash, if @code{flagStyle} is
141 not set. Main note scripts don't end up on the grace note.
143 @mudelafile{grace.ly}
145 @section Beams, slurs and other spanners
147 Beaming is generated automatically. Beams may cross bar lines. In that
148 case, line breaks are forbidden. Yet clef and key signatures are
149 hidden just as with breakable bar lines.
151 @mudelafile{beaming.ly}
153 Beams should behave reasonably well, even under extreme circumstances.
154 Stems may be short, but noteheads should never touch the beam.
156 @mudelafile{beam-extreme.ly}
158 Beams should always reach the middle staff line. The second beam
159 counting from the note head side, should never be lower than the
160 second staff line. This does not hold for grace note beams.
161 Override with @code{noStemExtend}.
163 @mudelafile{beam-position.ly}
165 Slurs should look nice and symmetric. The curvature may increase
166 only to avoid noteheads, and as little as possible. Slurs never
167 run through noteheads or stems.
169 @mudelafile{slur-nice.ly}
170 @mudelafile{slur-symmetry.ly}
171 @mudelafile{slur-symmetry-1.ly}
173 Across line breaks, slurs behave nicely. On the left, they extend to
174 just after the preferatory matter, and on the right to the end of the
175 staff. A slur should follow the same vertical direction it would have
178 @mudelafile{slur-broken-trend.ly}
180 Ties are strictly horizontal. They are placed in between note heads.
181 The horizontal middle should not overlap with a staffline.
185 When tieing chords, the outer slurs point outwards, the inner slurs
186 point away from the center of the staff. Override with
187 @code{tieVerticalDirection}.
189 @mudelafile{tie-chord.ly}
191 When tieing notes with accidentals across a bar boundary, the accidental
192 must not be drawn on the note in the new bar. Instead, the next note of
193 the same pitch in this bar should always show the accidental (even if
194 it's natural). Slurring a accidentaled note to a natural one across bar
195 boundaries should be explicit.
197 Pitches can be verified by printing them with the @code{NoteNames} context.
199 @mudelafile{tie-accidental.ly}
201 Beams can be typeset over fixed distance aligned staffs, beam
202 beautification doesn't really work, but knees do. Beams should be
203 behave well, wherever the switching point is.
205 @mudelafile{beam-cross-staff.ly}
207 The same goes for slurs. They behave decently when broken across
210 @mudelafile{slur-cross-staff.ly}
212 Tuplets are indicated by a bracket with a number. There should be no
213 bracket if there is one beam that matches the length of the tuplet.
214 The bracket does not interfere with the stafflines, and the number is
215 centered in the gap in the bracket.
219 @section Property details
221 More specific settings take precendence over less specific settings. The
222 second slur has slurDirection set to down, overriding the stemup setting.
224 @mudelafile{generic-property-override.ly}
228 LilyPond has three modes for repeats: folded, unfolded and
229 semi-unfolded. Unfolded repeats are fully written out. Semi unfolded
230 repeats have the body written and all alternatives sequentially.
231 Folded repeats have the body written and all alternatives
232 simultaneo.ly. If the number of alternatives is larger than the
233 repeat count, the excess alternatives are ignored. If the number of
234 alternatives is smaller, the first alternative is multiplied to get to
235 the number of repeats.
239 @mudelafile{repeat-unfold.ly}
241 Volta (Semi folded) behavior. Voltas can start on non-barline moments.
242 If they don't barlines should still be shown.
244 @mudelafile{repeat-volta.ly}
246 Folded. This doesn't make sense without alternatives, but it works.
248 @mudelafile{repeat-fold.ly}
250 Across linebreaks, the left edge of a first and second alternative
251 bracket should be equal
253 @mudelafile{repeat-line-break.ly}
255 Auto change piano staff switches voices between up and down staffs
256 automatically; rests are switched along with the coming note.
258 @mudelafile{auto-change.ly}
262 Lyrics can be set to a melody automatically. Excess lyrics will be
263 dumped. Lyrics will not be set over rests. You can have melismata
264 either by setting a property melismaBusy, or by setting
265 automaticMelismas (which will set melismas during slurs and ties). If
266 you want a different order than first Music, then Lyrics, you must
267 precook a chord of staffs/lyrics and label those. Of course
268 @code{\rhythm} ignores any other rhythms in the piece. Hyphens and
269 extenders do not assume anything about lyric lengths, so they continue
272 @mudelafile{lyric-combine.ly}
276 @mudelafile{lyrics-multi-stanza.ly}
278 @section Multiple notes
280 Rests should not collide with beams, stems and noteheads. Rests may
281 be under beams. Rests should be move by integral number of spaces
282 inside the staff, and by half spaces outside. Notice that the half
283 and whole rests just outside the staff get ledger lines in different
286 @mudelafile{rest-collision.ly}
288 Normal collisions. We have support for polyphony, where the
289 middle voices are horizontally shifted.
291 @mudelafile{collisions.ly}
293 The number of stafflines of a staff can be set with the property
294 numberOfStaffLines. Ledger lines both on note heads and rests are
295 adjusted. Barlines also are adjusted.
298 @mudelafile{number-staff-lines.ly}
302 In a limited number of cases, LilyPond corrects for optical spacing
303 effects. In this example, space for opposite pointed stems is adjusted
305 @mudelafile{stem-spacing.ly}
307 If there are accidentals in the music, we add space, but the space
308 between note and accidentals is less than between the notes with the
309 same value. Clef changes also get extra space, but not as much as
312 Even if a line is very tightly spaced, there will still be room
313 between prefatory matter and the following notes. The space after the
314 prefatory is very rigid. In contrast, the space before the barline
315 must stretch like the space within the measure.
319 @mudelafile{spacing-tight.ly}
323 @mudelafile{spacing-natural.ly}
327 @mudelafile{spacing-loose.ly}
329 Adding a @code{Bar_engraver} to the LyricsVoice context makes sure that
330 lyrics don't collide with barlines.
332 @mudelafile{lyrics-bar.ly}
334 Text is set with empty horizontal dimensions. The boolean property
335 textNonEmpty is used to respect the horizontal size of text.
337 @mudelafile{non-empty-text.ly}
346 @section Global stuff
348 Breaks can be encouraged and discouraged using @code{\break} and
349 @code{\nobreak}. They are abbrevs for @code{\penalty} commands.
351 @mudelafile{break.ly}
353 Markings that are attached to (invisible) barlines are
354 delicate: the are attached to the rest of the score without the score
355 knowing it. Consequently, they fall over often.
357 @mudelafile{bar-scripts.ly}
359 Staff margins are also markings attached to barlines. They should be
360 left of the staff, and be centered vertically wrt the staff. They may
361 be on normal staffs, but also on compound staffs, like the PianoStaff
363 @mudelafile{staff-margin.ly}
365 Breathing signs, also used for phrasing, do normally not influence
366 global spacing -- only if space gets tight, notes are shifted to make
367 room for the breathing sign. Breathing signs break beams running
368 through their voice. In the following example, the notes in the first
369 two measures all have the same distance from each other:
371 @mudelafile{breathing-sign.ly}
373 Hara kiri staffs kill themselves if they are empty. This example really
374 contains two staffs, but the second contains only spaces, and is
377 @mudelafile{hara-kiri-short.ly}
379 In orchestral scores and hymns, voices are traditionally combined onto
380 one staff. LilyPond has a part combiner, that combines or separates two
381 voices according to actual rhythm and pitch. User-defined texts such as
382 ``solo'' and ``@`a2'' are typeset automagically, as appropriate.
384 @mudelafile{part-combine.ly}
387 Fonts are available in a default set of sizes: 11, 13, 16, 20, 23 and
388 26pt staffheight. Sizes of the text fonts and symbol fonts are made
389 to match the staff dimensions.
391 @mudelafile[nonfragment]{size11.ly}
393 @mudelafile[nonfragment]{size13.ly}
395 @mudelafile[nonfragment]{size16.ly}
397 @mudelafile[nonfragment]{size20.ly}
399 @mudelafile[nonfragment]{size23.ly}
401 @mudelafile[nonfragment]{size26.ly}
404 @section Clefs and Time Signatures
406 The transparent clef should not occupy any space and with style
407 @code{fullSizeChanges}, the changing clef should be typeset in full
408 size. For octaviated clefs, the ``8'' should appear closely above or
409 below the clef respectively. The ``8'' is processed in a convoluted
410 way, so this is fragile as well.
412 @mudelafile{clefs.ly}
415 Key signatures appear on key changes. They may also
416 appear without barlines. The restoration accidentals are not printed at
417 the start of the line. If @code{createKeyOnClefChange} is set, they're
418 also created on a clef change.
426 @c the input file is too long and does not test for specific bugs
428 By default, time signatures are written with two numbers. With style
429 ``C'', 4/4 and 2/2 are written with their corresponding symbols and
430 with style ``old'', 2/2, 3/2, 2/4, 3/4, 4/4, 6/4, 9/4, 4/8, 6/8 and
431 9/8 are typeset with symbols, all other signatures retain the default
432 layout. The style ``1'', gives single number signatures for all
435 \mu delafile{time.ly}
440 @section Hacks and Features
442 As a last resort, the placement of items can be adjusted manually, by
443 setting the @code{extra-offset} of an output object.
445 @mudelafile{generic-output-property.ly}
447 The same mechanism can be used to force pagebreaks.
449 @mudelafile{between-systems.ly}