1 ;;;; interface-description.scm -- part of generated backend documentation
3 ;;;; source file of the GNU LilyPond music typesetter
5 ;;;; (c) 1998--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
6 ;;;; Jan Nieuwenhuizen <janneke@gnu.org>
9 ; should include default value?
13 ;;; Score elements are called `objects' now and then, which gets
14 ;;; rather confusing, we now have `elements', `items', `spanners'
18 (define all-interfaces '())
20 (define (lily-interface symbol description props)
21 (set! all-interfaces (acons symbol (list symbol
23 props) all-interfaces)
27 (define (grob-description . interfaces)
28 (let* ((ifs (cons grob-interface interfaces))
29 (props (map caddr ifs))
30 ; (prop-typep-pairs (map (lambda (x) (cons (car x) (cadr x)))
31 ; (apply append props)))
34 (list (cons 'separator "\n\n\n") ;easy printing.
35 (cons 'interfaces syms)
36 (cons 'interface-descriptions ifs)
37 ; (cons 'interface-descriptions (cadr merged))
38 ;; description of the grob itself?
39 ; (cons 'properties prop-typep-pairs)
45 "All grobs support this"
70 #'thickness= weight of beams, in staffspace
82 vertical-position-quant-function
84 outer-stem-length-limit
91 'staff-spacing-interface
97 'note-spacing-interface
114 'axis-group-interface
115 "a group of coupled grobs"
122 'note-column-interface
123 "Stem and noteheads combined"
137 beamed-minimum-lengths
169 extremity-offset-alist
179 'side-position-interface
180 "Position a victim object (this one) next to other objects (the support).
181 #'direction = where to put the victim object (left or right?)
187 side-relative-direction
198 'accidentals-interface
210 'line-of-score-interface
211 "Super grob, parent of all:
213 The columns of a score that form one line. The toplevel grob. Any
214 grob has a Line_of_score as both X and Y reference point. The
215 Paper_score contains one grob of this type. Control enters the
216 Grob dependency calculation from this single Line_of_score
219 between-system-string
221 before-line-breaking-callback
222 after-line-breaking-callback
231 '( style stem-attachment-function note-character ))
242 'rhythmic-head-interface
258 'tuplet-bracket-interface
259 "A bracket with a number in the middle, used for tuplets."
264 tuplet-bracket-visibility
265 tuplet-number-visibility
273 " Order grobs top to bottom/left to right/right to left etc."
287 "read by align-interface"
295 'break-aligned-interface
296 "Items that are aligned in prefatory matter"
305 'chord-name-interface
306 "generate a chord name"
307 '( pitches inversion bass))
311 'time-signature-interface
312 "A time signature, in different styles.
313 The following values for 'style are are recognized:
317 4/4 and 2/2 are typeset as C and struck C, respectively. All
318 other time signatures are written with two digits.
321 2/2, 3/2, 2/4, 3/4, 4/4, 6/4, 9/4, 4/8, 6/8 and 9/8 are
322 typeset with old-style mensuration marks. All other time
323 signatures are written with two digits.
326 All time signatures are typeset with a single
327 digit, e.g. 3/2 is written as 3. (Any symbol starting
328 with the digit @code{1} will do.)
330 @item @code{C}@var{M}@code{/}@var{N},
331 @code{old}@var{M}@code{/}@var{N} or
333 Tells LilyPond to use a specific symbol as time signature,
334 regardless of the actual time signature.
337 See also the test-file @file{input/test/time.ly}.
346 This is a request to print a special bar symbol. It replaces the
347 regular bar symbol with a special
348 symbol. The argument @var{bartype} is a string which specifies the
349 kind of bar to print. Options are @code{\":|\"}
350 @cindex \"|A@@@code{:|}
353 @cindex \"|B@@@code{|:}
355 @cindex \"|C@@@code{:|:}
358 @cindex \"|D@@@code{||}
360 @cindex \"|E@@@code{|.}
363 @cindex \"|F@@@code{.|}
365 @cindex \"|G@@@code{.|.}
368 These produce, respectively, a right repeat, a left repeat, a double
369 repeat, a double bar, a start bar, an end bar, and a thick double bar.
370 If @var{bartype} is set to @code{\"empty\"} then nothing is printed,
371 but a line break is allowed at that spot.
374 '(bar-size-procedure kern thin-kern hair-thickness thick-thickness glyph bar-size break-glyph-function ))
381 padding -- horizontal padding. This is useful if a crescendo is set next to a text like `mf'
384 '( grow-direction thickness height padding
390 "Functions and settings for drawing an arpeggio symbol (a wavy line left to noteheads."
391 '(stems arpeggio-direction))
396 'note-collision-interface
397 "An object that handles collisions between notes with different
398 stem directions and horizontal shifts. Most of the interesting
399 properties are to be set in @ref{note-column-interface}"
400 '(merge-differently-dotted note-width))
406 "A custos is a staff context symbol that appears at the end of a
407 staff line with monophonic musical contents (i.e. with a single
408 voice). It anticipates the pitch of the first note of the following
409 line and thus helps the player or singer to manage line breaks
410 during performance, thus enhancing readability of a score.
412 Custodes were frequently used in music notation until the 16th
413 century. There were different appearences for different notation
414 styles. Nowadays, they have survived only in special forms of
415 musical notation such as via the editio vaticana dating back to the
416 beginning of the 20th century.
418 [TODO: add to glossary]"
429 "The dots to go with a notehead/rest. A separate interface, since they
430 are a party in collision resolution.
431 #'direction is the Direction to handle staff-line collisions in."
432 '(direction dot-count))
437 "Any symbol that is typeset through fixed sets of glyphs (ie. fonts)"
438 '(font-style font-series font-shape font-family font-name
439 font-design-size font-relative-size)
446 "A scheme markup text"
447 '(text align baseline-skip lookup raise kern magnify))
451 'dot-column-interface
452 "Interface that groups dots so they form a column"
459 "Any kind of loudness sign"
467 "A fingering instruction"
473 'separation-spanner-interface
474 "Spanner that containing @code{separation-item-interface} grobs to calculate rods"
479 'text-script-interface
486 'grace-alignment-interface
487 "put grace notes in line"
495 'hara-kiri-group-interface
496 " As Vertical_group_spanner, but keep track of interesting items. If
497 we don't contain any interesting items after linebreaking, then
498 gracefully commit suicide. Objective: don't disgrace Lily by
499 typesetting empty lines in orchestral scores."
500 '( items-worth-living )
505 'line-spanner-interface
506 "Generic line drawn between two objects, eg. for use with glissandi.
507 gap is measured in staff-spaces. "
509 '(gap dash-period dash-length line-thickness type
514 'lyric-hyphen-interface
515 "A centred hyphen is a simple line between lyrics used to divide
516 syllables. The length of the hyphen line should stretch based on the
517 size of the gap between syllables."
519 '( thickness height minimum-length word-space
524 'key-signature-interface
525 "A group of accidentals."
534 'lyric-extender-interface
535 "The extender is a simple line at the baseline of the lyric
536 that helps show the length of a melissima (tied/slurred note)."
546 'lyric-syllable-interface
547 "a single piece of lyrics"
551 ignore-length-mismatch
566 'multi-measure-rest-interface
567 "A rest that spans a whole number of measures. For typesetting the
568 numbers, fields from font-interface may be used.
570 padding is the space between number and rest. Measured in staffspace.
573 '( columns expand-limit minimum-width padding))
577 'paper-column-interface
580 '(column-space-strength before-musical-spacing-factor
581 stem-spacing-correction before-grace-spacing-factor when bounded-by-me
582 dir-list shortest-playing-duration shortest-starter-duration
583 contains-grace extra-space stretch-distance ))
589 "A porrectus ligature, joining two note heads into a single grob."
595 'spaceable-element-interface
596 "An grob (generally a Paper_column) that takes part in the
606 'rest-collision-interface
607 "Move around ordinary rests (not multi-measure-rests) to avoid
625 'script-column-interface
626 "An interface that sorts scripts according to their @code{script-priority}"
632 'spacing-spanner-interface
633 " SPACE = arithmetic_multiplier * ( C + log2 (TIME) ))
634 The space taken by a note is determined by the formula
638 where TIME is the amount of time a note occupies. The value of C is
639 chosen such that the smallest space within a measure is
640 arithmetic_basicspace:
642 C = arithmetic_basicspace - log2 (mininum (SHORTEST, 1/8))
644 The smallest space is the one following the shortest note in the
645 measure, or the space following a hypothetical 1/8 note. Typically
646 arithmetic_basicspace is set to a value so that the shortest note
647 takes about two noteheads of space (ie, is followed by a notehead of
651 2*quartwidth = arithmetic_multiplier * ( C + log2 (SHORTEST) ))
653 @{ using: C = arithmetic_basicspace - log2 (mininum (SHORTEST, 1/8)) @}
654 @{ assuming: SHORTEST <= 1/8 @}
656 = arithmetic_multiplier *
657 ( arithmetic_basicspace - log2 (SHORTEST) + log2 (SHORTEST) )
659 = arithmetic_multiplier * arithmetic_basicspace
661 @{ choose: arithmetic_multiplier = 1.0*quartwidth (why?) @}
663 = quartwidth * arithmetic_basicspace
667 arithmetic_basicspace = 2/1 = 2
670 If you want to space your music wider, use something like:
672 arithmetic_basicspace = 4.;
676 maximum-duration-for-spacing
677 arithmetic-basicspace
678 arithmetic-multiplier
684 'staff-symbol-referencer-interface
686 "Object whose Y position is meaning with reference to a staff
687 symbol. Objects that have this interface should include
688 Staff_symbol_referencer::callback in their Y-offset-callback.
697 'staff-symbol-interface
698 "This spanner draws the lines of a staff. The middle line is
708 'stem-tremolo-interface
710 '( stem beam-width beam-thickness beam-space-function
715 'separation-item-interface
716 "Item that computes widths to generate spacing rods.
718 Calc dimensions for the Separating_group_spanner; this has to be
719 an item to get dependencies correct. It can't be an grob_group
720 since these usually are in a different X_group
728 'sustain-pedal-interface
734 'system-start-delimiter-interface
735 "#'style can be bar-line, bracket or brace"
736 '(bar-line-collapse-height brace-collapse-height bracket-collapse-height
737 thickness arch-height arch-angle arch-thick
738 arch-width bracket-thick glyph ))
742 'text-spanner-interface
743 "generic text spanner"
756 "A tie connecting two noteheads.
757 direction = Forced direction for all ties"
774 'tie-column-interface
775 "that sets tie directions in a tied chord"
780 'percent-repeat-interface
781 "Repeats that look like percent signs"
785 'volta-bracket-interface
786 "Volta bracket with number"
796 "A bar line that spans other barlines (typically used to get cross-staff barlines."
801 (primitive-eval (cons
803 (map (lambda (x) (list 'define (car x) (list 'quote (cdr x))))
807 (define (interface-names) (map (lambda (x) (symbol->string (car x))) all-interfaces))