2 ; should include default value?
4 ;;; ::::::: should generate documentation for score elements from here.
6 (define (property-description symbol type? description)
7 (list symbol type? description))
9 (define (lily-interface symbol description props)
17 (define (uniqued-alist alist acc)
19 (if (assoc (caar alist) acc)
20 (uniqued-alist (cdr alist) acc)
21 (uniqued-alist (cdr alist) (cons (car alist) acc)
24 (define (element-description name . interfaces)
25 (let* ((ifs (cons general-element-interface interfaces))
26 (props (map caddr ifs))
27 (prop-typep-pairs (map (lambda (x) (cons (car x) (cadr x)))
28 (apply append props)))
31 (list (cons 'separator "\n\n\n") ;easy printing.
33 (cons 'interfaces syms)
34 (cons 'interface-descriptions ifs)
35 ; (cons 'interface-descriptions (cadr merged))
36 ;; description of the element itself?
37 (cons 'properties prop-typep-pairs)
41 (define general-element-interface
43 'general-element-interface
44 "All elements support this"
46 (property-description 'X-offset-callbacks list? "list of functions, each taking an element and axis argument. The function determine the position relative to this element's parent. The last one in the list is called first")
47 (property-description 'Y-offset-callbacks list? "see <code> X-offset-callbacks</code>")
48 (property-description 'X-extent-callback procedure? "procedure taking an element and axis argument, returning a number-pair. The return value is the extent of the element.")
49 (property-description 'Y-extent-callback procedure? "see <code> X-extent-callback </code>")
50 (property-description 'font-relative-size integer? "")
51 (property-description 'extra-offset number-pair? "pair of reals (a cons) forcing an extra offset before outputting")
52 (property-description 'interfaces list? "list of symbols indicating the interfaces supported by this object. Is initialized from the <code>meta</code> field.")
53 (property-description 'dependencies list? "list of score-element pointers that indicate who to compute first for certain global passes")
54 (property-description 'no-spacing-rods boolean? "read from elements: boolean that makes Separation_item ignore this item (MOVE ME TO ITEM)")
55 (property-description 'extra-extent-X number-pair? "enlarge in X dimension by this much, measured in staff space")
56 (property-description 'extra-extent-Y number-pair? "see <code>extra-extent-Y</code>")
57 (property-description 'minimum-extent-X number-pair? "minimum size in X dimension, measured in staff space")
58 (property-description 'minimum-extent-Y number-pair? "see <code>minimum-extent-Y</code>")
59 (property-description 'origin ly-input-location? "location in input file of the definition")
60 (property-description 'transparent boolean? "This is almost the
61 same as setting molecule-callback to #f, but this retains the
62 dimensions of this element, which means that you can erase elements
64 (property-description 'molecule-callback procedure? "Function taking graphical element as argument, returning a Scheme encoded Molecule")
68 (define beam-interface
73 (property-description 'y-position number? "position of left edge")
74 (property-description 'height number? "dy")
75 (property-description 'flag-width-function procedure? "")
76 (property-description 'damping integer? "amount of beam slope damping should beam slope be damped? 0: no, 1: yes, 100000: horizontal beams ")
77 (property-description 'default-neutral-direction dir? "which
78 direction to choose if we're in the middle of the staff ")
79 (property-description 'thickness number? "weight of beams, in staffspace")
80 (property-description 'space-function procedure? "function of type multiplicity -> real (in staffspace)")
81 (property-description 'beamed-stem-shorten number? "")
82 (property-description 'height-quants number? "")
83 (property-description 'vertical-position-quant-function procedure? "")
84 (property-description 'dir-function procedure? "")
85 (property-description 'damping number? "damping factor.")
86 (property-description 'outer-stem-length-limit number? "catch
87 suspect beam slopes, set slope to zero if outer stem is lengthened
88 more than this (in staffspace)")
89 (property-description 'slope-limit number? "set slope to zero if slope is running away steeper than this.")
97 (define clef-interface
102 (property-description 'non-default boolean? "not set because of existence of a bar?")
103 (property-description 'change boolean? "is this a change clef (smaller size)?")
104 (property-description 'glyph string? "a string determining what glyph is typeset")
108 (define axis-group-interface
110 'axis-group-interface
111 "a group of coupled elements"
113 (property-description 'axes list? "list of axis (number) in which this group works")
116 (define note-column-interface
118 'note-column-interface
119 "Stem and noteheads combined"
121 (property-description 'horizontal-shift integer? "integer that identifies ranking of note-column for horizontal shifting.")
122 (property-description 'force-hshift number? "amount of collision_note_width that overides automatic collision settings.")
123 (property-description 'merge-differently-dotted boolean? "merge black noteheads with differing dot count in collisions.")
127 (define stem-interface
132 (property-description 'thickness number? "thickness, measured in stafflinethickness")
133 (property-description 'beamed-lengths list? "list of stem lengths given beam multiplicity ")
134 (property-description 'beamed-minimum-lengths list? "list of minimum stem lengths given beam multiplicity")
135 (property-description 'stem-centered boolean? "Center stems on note heads. Useful for mensural notation")
136 (property-description 'lengths list? "Stem length given multiplicity of flag")
137 (property-description 'beam ly-element? "pointer to the beam, if applicable")
138 (property-description 'stem-shorten list? "shorten stems in forced directions given flag multiplicity")
139 (property-description 'duration-log integer? "log of the duration, ie. 0=whole note, 1 = half note, etc.")
140 (property-description 'beaming number-pair? "number of beams extending to left and right")
141 (property-description 'default-neutral-direction dir? "Where to go if we're in the middle of the staff")
142 (property-description 'stem-end-position number? "Where does the stem end (the end is opposite to the support-head")
143 (property-description 'support-head ly-element? "the note head at
144 one end of the stem")
145 (property-description 'heads list? "list of note heads")
146 (property-description 'direction dir? "up or down")
147 (property-description 'stem-length number? "length of stem")
148 (property-description 'style string? "") ; symbol!?
149 (property-description 'flag-style string? "") ; symbol!?
150 (property-description 'dir-forced boolean? "set if direction has been forced; read by Beam.")
154 (define slur-interface
159 (property-description 'de-uglify-parameters list? "list of 3 real constants. They define the valid areas for the middle control points. Used in de_uglyfy. They are a bit empirical.")
160 (property-description 'details list? "alist containing contaning a few magic constants.")
161 (property-description 'attachment pair? "cons of symbols, '(LEFT-TYPE . RIGHT-TYPE), where both types may be alongside-stem, stem, head or loose-end")
162 (property-description 'direction dir? "up or down?")
163 (property-description 'attachment-offset pair? "cons of offsets, '(LEFT-offset . RIGHT-offset). This offset is added to the attachments to prevent ugly slurs.")
164 (property-description 'beautiful number? "number that dictates when a slur should be de-uglyfied. It correlates with the enclosed area between noteheads and slurs. A value of 0.1 yields only undisturbed slurs, a value of 5 will tolerate quite high blown slurs.")
165 (property-description 'y-free number? "minimal vertical gap between slur and noteheads or stems")
166 (property-description 'control-points list? "[internal] control points of bezier curve")
167 (property-description 'extremity-rules list? "an alist (procedure slur dir) -> attachment to determine the attachment (see above). If procedure returns #t, attachment is used. Otherwise, the next procedure is tried.")
168 (property-description 'extremity-offset-alist list? "an alist (attachment stem-dir*dir slur-dir*dir) -> offset. The offset adds to the centre of the notehead, or stem.")
169 (property-description 'thickness list? "The thickness[stafflinethickness] of slur in the centre.")
170 (property-description 'dashed number? "[FIXME: use dash-period/dash length; see text-spanner] number representing the length of the dashes.")
176 (define side-position-interface
178 'side-position-interface
179 "Position a victim object (this one) next to other objects (the support)."
181 (property-description 'side-support list? "the support, a list of score elements")
182 (property-description 'direction-source ly-element? "in case side-relative-direction is set, which element to get the direction from ")
183 (property-description 'direction dir? "where to put the victim object (left or right?)")
184 (property-description 'side-relative-direction dir? "if set: get the direction from a different object, and multiply by this.")
185 (property-description 'minimum-space number? "minimum distance that the victim should move (after padding)")
186 (property-description 'padding number? "add this much extra space between victim and support")
187 (property-description 'self-alignment-X number? "real number: -1 =
188 left aligned, 0 = center, 1 right-aligned in X direction. <p> Set to
189 an element pointer, if you want that element to be the center. In
190 this case, the center element should have this object as a reference
193 (property-description 'self-alignment-Y number? "like self-alignment-X but for Y axis")
198 (define accidentals-interface
200 'accidentals-interface
203 (property-description 'left-padding number? "space left of accs")
204 (property-description 'right-padding number? "space right of accs")
208 (define line-of-score-interface
210 'line-of-score-interface
211 "Super element, parent of all:
213 The columns of a score that form one line. The toplevel element.
214 Any element has a Line_of_score as both X and Y reference
215 point. The Paper_score contains one element of this type. Control
216 enters the Score_element dependency calculation from this single
217 Line_of_score object."
219 (property-description 'between-system-string string? "string
220 to dump between two systems. Useful for forcing pagebreaks")
221 (property-description 'spacing-procedure procedure? "procedure taking
222 graphical element as argument. This is called after before-line-breaking-callback, but before the actual line breaking itself. Return value is ignored")
223 (property-description 'before-line-breaking-callback procedure?
224 "Procedure taking graphical element as argument.
225 This procedure is called (using dependency resolution) before line breaking, but after generating discretionary items. Return value is ignored")
226 (property-description 'after-line-breaking-callback procedure?
227 "Procedure taking graphical element as argument.
228 This procedure is called (using dependency resolution) after line breaking. Return value is ignored")
229 (property-description 'all-elements list? "list of all score elements in this line. Needed for protecting elements from GC.")
230 (property-description 'columns list? "list of all paper columns")
233 (define note-head-interface
238 (property-description 'style symbol? "symbol that sets note head style")
242 (define note-name-interface
247 (property-description 'style symbol? "symbol that sets note name style")
252 (define rhythmic-head-interface
254 'rhythmic-head-interface
257 (property-description 'dot ly-element? "reference to Dots object.")
258 (property-description 'stem ly-element? "pointer to Stem object")
259 (property-description 'duration-log integer? "2-log of the notehead duration")
262 (define rest-interface
267 (property-description 'style string? "string specifying glyph style"))))
269 (define tuplet-bracket-interface
271 'tuplet-bracket-interface
272 "A bracket with a number in the middle, used for tuplets."
274 (property-description 'beams list? "list of beam ptrs.")
275 (property-description 'columns list? " list of note-columns.")
276 (property-description 'number-gap number? "")
277 (property-description 'delta-y number? "amount of ascension")
278 (property-description 'thick number? "thickness, in stafflinethickness")
283 (define align-interface
286 " Order elements top to bottom/left to right/right to left etc."
288 (property-description 'stacking-dir dir? "stack contents of elements in which direction ?")
289 (property-description 'align-dir dir? "Which side to align? -1: left side, 0: around center of width, 1: right side")
290 (property-description 'threshold number-pair? "(cons MIN MAX), where MIN and MAX are dimensions in staffspace")
291 (property-description 'alignment-done boolean? "boolean to administrate whether we've done the alignment already (to ensure that the process is done only once)")
292 (property-description 'center-element ly-element? "element which will be at the
293 center of the group after aligning (when using
294 Align_interface::center_on_element). ")
295 (property-description 'elements list? "to be aligned elements ")
296 (property-description 'axes list? "list of axis numbers. Should contain only one number.")
299 (define aligned-interface
302 "read by align-interface"
304 (property-description 'minimum-space number-pair? "(cons LEFT RIGHT)")
305 (property-description 'extra-space number-pair? "(cons LEFT RIGHT)")
308 (define break-aligned-interface
310 'break-aligned-interface
311 "Items that are aligned in prefatory matter"
313 (property-description 'break-align-symbol symbol? "the index in the spacing table (symbol) of the to be aligned item.")
314 (property-description 'visibility-lambda procedure? "a function that takes the break direction and returns a cons of booleans containing (TRANSPARENT . EMPTY)")
315 (property-description 'breakable boolean? "boolean indicating if this is a breakable item (clef, barline, key sig, etc.)")
318 (define chord-name-interface
320 'chord-name-interface
321 "generate a chord name"
323 (property-description 'pitches list? "list of musical-pitch")
324 (property-description 'inversion list? " musical-pitch, optional")
325 (property-description 'bass list? " musical-pitch, optional")
328 (define time-signature-interface
330 'time-signature-interface
331 "A time signature, in different styles"
333 (property-description 'fraction number-pair? "")
334 (property-description 'style string? "")
337 (define bar-line-interface
342 (property-description 'barsize-procedure procedure? "how to compute the size of a bar line")
343 (property-description 'kern number? "space after a thick line")
344 (property-description 'thin-kern number? "space after a hair-line")
345 (property-description 'hair-thickness number? "thickness, measured in stafflinethickness")
346 (property-description 'thick-thickness number? "thickness, measured in stafflinethickness")
347 (property-description 'glyph string? "what kind barline? A concatenation of |, : and .")
348 (property-description 'bar-size number? "")
349 (property-description 'break-glyph-function procedure? "function taking glyph and break-direction, returning the glyph at a line break")
355 (define hairpin-interface
360 (property-description 'grow-direction dir? "crescendo or decrescendo?")
361 (property-description 'thickness number? "thickness, measured in stafflinethickness")
362 (property-description 'height number? "height, measured in staffspace in ")
365 (define arpeggio-interface
370 (property-description 'stems list? "list of stem objects, corresponding to the notes that the arpeggio has to be before.")
375 (define note-collision-interface
377 'note-collision-interface
380 (property-description 'note-width 'number? "unit for horizontal translation, measured in staff-space.")
382 (define dot-interface
385 "The dots to go with a notehead/rest. A separate interface, since they
386 are a party in collision resolution."
388 (property-description 'dot-count integer? "number of dots")
391 (define text-interface
394 "A scheme markup text"
396 (property-description 'text (lambda (x) (or (string? x) (list? x))) "
397 Scheme markup text. It is defined as follows:
400 TEXT : STRING | (MARKUP SENTENCE)<br>
401 MARKUP: PROPERTY | ABBREV<br>
402 SENTENCE: TEXT | SENTENCE TEXT<br>
403 PROPERTY: (key . value)<br>
404 ABBREV: rows lines roman music bold italic named super sub text, or any font-style
407 So, TEXT is either a string, or a list of which the CAR is a MARKUP.
408 MARKUP is either a CONS: an element property '(key . value) or a symbol:
409 a predefined abbreviation for a list of element properties.
412 The following abbreviations are currently defined:
414 <dt>rows<dd> horizontal mode: set all text on one line (default)
415 <dt>lines<dd> vertical mode: set every text on new line
416 <dt>roman<dd> select roman font
417 <dt>music<dd> select feta font
418 <dt>bold<dd> select bold series
419 <dt>italic<dd> select italic shape
420 <dt>named<dd> lookup by character name
421 <dt>text<dd> plain text lookup (by character value)
422 <dt>super<dd> superscript
423 <dt>sub<dd> subscript
424 <dt> any font-style<dd> finger volta timesig mmrest mark script large Large dynamic
427 (property-description 'font-style symbol? "font definition for a special purpose, one of: finger volta timesig mark script large Large dynamic")
428 (property-description 'font-series symbol? "partial font definition: medium, bold")
429 (property-description 'font-shape symbol? "partial font definition: upright or italic")
430 (property-description 'font-family symbol? "partial font definition: music roman braces dynamic math ...")
431 (property-description 'font-name symbol? "partial font definition: base name of font file FIXME: should override other partials")
432 (property-description 'font-point-size number? "partial font definition: exact font size in points FIXME: should override font-relative-size")
433 (property-description 'font-relative-size number? "partial font definition: the relative size, 0 is style-sheet's normal size, -1 is smaller, +1 is bigger")
435 ;; Should move this somewhere else?
436 (property-description 'align number? "the alignment of the text, 0 is horizontal, 1 is vertical")
437 (property-description 'lookup symbol? "lookup method: 'value for plain text, 'name for character-name")
438 (property-description 'raise number? "height for text to be raised (a negative value lowers the text")
439 (property-description 'kern number? "amount of extra white space to add before text. This is `relative'(?) to the current alignment.")
440 (property-description 'magnify number? "the magnification factor. FIXME: doesn't work for feta fonts")
443 (define dot-column-interface
445 'dot-column-interface
446 "Interface that groups dots so they form a column"
450 (define dynamic-interface
453 "Any kind of loudness sign"
458 (define finger-interface
461 "A fingering instruction"
465 (define separation-spanner-interface
467 'separation-spanner-interface
468 "Spanner that containing <code>separation-item-interface</code> elements to calculate rods"
471 (define text-script-interface
473 'text-script-interface
478 (define grace-alignment-interface
480 'grace-alignment-interface
481 "put grace notes in line"
483 (property-description 'horizontal-space number? "amount of space to add after a note (in staff-space)")
487 (define hara-kiri-group-interface
489 'hara-kiri-group-interface
490 " As Vertical_group_spanner, but keep track of interesting items. If
491 we don't contain any interesting items after linebreaking, then
492 gracefully commit suicide. Objective: don't disgrace Lily by
493 typesetting empty lines in orchestral scores."
495 (property-description 'items-worth-living list? "list of interesting items. If empty in a particular system, clear that system.")
500 (define lyric-hyphen-interface
502 'lyric-hyphen-interface
503 "A centred hyphen is a simple line between lyrics used to divide
504 syllables. The length of the hyphen line should stretch based on the
505 size of the gap between syllables."
508 (property-description 'thickness number? "thickness of line (in stafflinethickness)")
509 (property-description 'height number? "vertical offset (in staffspace)")
511 (property-description 'minimum-length number? "try to make the hyphens at least this long. Also works as a scaling parameter for the length")
512 (property-description 'word-space number? "elongate left by this much (FIXME: cumbersome semantics)")
515 (define key-signature-interface
517 'key-signature-interface
518 "A group of accidentals."
520 (property-description 'c0-position integer? "integer indicating the position of central C")
521 (property-description 'old-accidentals list? "list of (pitch, accidental) pairs")
522 (property-description 'new-accidentals list? "list of (pitch, accidental) pairs")
525 (define lyric-extender-interface
527 'lyric-extender-interface
528 "The extender is a simple line at the baseline of the lyric
529 that helps show the length of a melissima (tied/slurred note)."
531 (property-description 'word-space number? "")
532 (property-description 'height number? "in stafflinethickness")
533 (property-description 'right-trim-amount number? "")
537 (define lyric-syllable-interface
539 'lyric-syllable-interface
540 "a single piece of lyrics"
542 (property-description 'word-space number? "")
546 (define mark-interface
553 (define multi-measure-rest-interface
555 'multi-measure-rest-interface
556 "A rest that spans a whole number of measures."
559 (property-description 'columns list? "list of paper-columns")
560 (property-description 'expand-limit integer? "maximum number of measures expanded in church rests")
561 (property-description 'minimum-width number? "minimum-width of rest symbol, in staffspace")
562 (property-description 'padding number? "padding between number and rest. Measured in staffspace.")
565 (define paper-column-interface
567 'paper-column-interface
570 (property-description 'column-space-strength number? "relative strength of space following breakable columns (eg. prefatory matter)")
571 (property-description 'before-musical-spacing-factor number?
572 "space before musical columns (eg. taken by accidentals) get this much
573 stretched when they follow a musical column, in absence of grace
574 notes. 0.0 means no extra space (accidentals are ignored)")
575 (property-description 'stem-spacing-correction number? "optical correction amount.")
576 (property-description 'before-grace-spacing-factor number? " stretch space this much if there are grace notes before the column")
577 (property-description 'when moment? "when does this column happen?")
578 (property-description 'bounded-by-me list? "list of spanners that have this
579 column as start/begin point. Only columns that have elements or act as bounds are spaced.")
580 (property-description 'dir-list list? "list of stem directions")
581 (property-description 'shortest-playing-duration moment? "duration of the shortest playing in that column.")
582 (property-description 'shortest-starter-duration moment? "duration of the shortest notes that starts exactly in this column.")
583 (property-description 'contains-grace boolean? "Used to widen entries for grace notes.")
584 (property-description 'extra-space number-pair? "pair of distances")
585 (property-description 'stretch-distance number-pair? "pair of distances")
588 (define spaceable-element-interface
590 'spaceable-element-interface
591 "An element (generally a Paper_column) that takes part in the
594 (property-description 'minimum-distances list? "list of rods (ie. (OBJ . DIST) pairs)")
595 (property-description 'ideal-distances list? "(OBJ . (DIST . STRENGTH)) pairs")
596 (property-description 'dir-list list? "list of stem directions, needed for optical spacing correction.")
599 (define rest-collision-interface
601 'rest-collision-interface
602 "Move around ordinary rests (not multi-measure-rests) to avoid
605 (property-description 'maximum-rest-count integer? "kill off rests so we don't more than this number left.")
606 (property-description 'minimum-distance number? "minimum distance between notes and rests.")
607 (property-description 'elements list? "list of elements (NoteColumn,
608 generally) participating in the collision. The
609 <code>rest-collision</code> property in <code>elements</code> is set
610 to a pointer to the collision")
613 (define script-interface
618 (property-description 'script-priority number? "A sorting key that determines in what order a script is within a stack of scripts")
621 (define script-column-interface
623 'script-column-interface
624 "An interface that sorts scripts according to their <code>script-priority</code>"
628 (define spacing-spanner-interface
630 'spacing-spanner-interface
633 (property-description 'maximum-duration-for-spacing moment? "space as if a duration of this type is available in this measure.")
634 (property-description 'arithmetic-basicspace number? "The space taken by a note is determined by the formula
636 SPACE = arithmetic_multiplier * ( C + log2 (TIME) ))
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
650 2*quartwidth = arithmetic_multiplier * ( C + log2 (SHORTEST) ))
652 { using: C = arithmetic_basicspace - log2 (mininum (SHORTEST, 1/8)) }
653 { assuming: SHORTEST <= 1/8 }
655 = arithmetic_multiplier *
656 ( arithmetic_basicspace - log2 (SHORTEST) + log2 (SHORTEST) )
658 = arithmetic_multiplier * arithmetic_basicspace
660 { choose: arithmetic_multiplier = 1.0*quartwidth (why?)}
662 = quartwidth * arithmetic_basicspace
666 arithmetic_basicspace = 2/1 = 2
668 If you want to space your music wider, use something like:
670 arithmetic_basicspace = 4.;
673 (property-description 'arithmetic-multiplier number? "see arithmetic-basicspace")
677 (define staff-symbol-interface
679 'staff-symbol-interface
680 "This spanner draws the lines of a staff. The middle line is
683 (property-description 'staff-space number? "Amount of line leading relative to global staffspace")
684 (property-description 'line-count integer? "Number of staff lines")
687 (define stem-tremolo-interface
689 'stem-tremolo-interface
692 (property-description 'stem ly-element? "pointer to the stem object.")
693 (property-description 'beam-width number? "width of the tremolo sign")
694 (property-description 'beam-thickness number? "thickness, measured in staffspace")
695 (property-description 'beam-space-function procedure? "function returning space given multiplicity")
698 (define separation-item-interface
700 'separation-item-interface
701 "Item that computes widths to generate spacing rods.
703 Calc dimensions for the Separating_group_spanner; this has to be
704 an item to get dependencies correct. It can't be an element_group
705 since these usually are in a different X_group
708 (property-description 'elements list? " -- list of items.")
711 (define sustain-pedal-interface
713 'sustain-pedal-interface
717 (define system-start-delimiter
719 'system-start-delimiter
722 (property-description 'collapse-height number? "")
723 (property-description 'thickness number? "thickness, measured in stafflinethickness")
725 ; Should collapse into (bracket . ((height . ) ... ))
727 (property-description 'arch-height number? "")
728 (property-description 'arch-angle number? "")
729 (property-description 'arch-thick number? "")
730 (property-description 'arch-width number? "")
731 (property-description 'bracket-thick number? "")
732 (property-description 'bracket-width number? "")
733 (property-description 'glyph symbol? "bar-line, bracket or brace")
736 (define text-spanner-interface
738 'text-spanner-interface
739 "generic text spanner"
741 (property-description 'dash-period number? "the length of one dash + white space")
742 (property-description 'dash-length number? "the length of a dash")
743 (property-description 'line-thickness number? "the thickness[stafflinethickness] of the line")
744 (property-description 'edge-height pair? "a cons that specifies the heights of the vertical egdes '(LEFT-height . RIGHT-height)")
745 (property-description 'edge-text pair? "a cons that specifies the texts to be set at the edges '(LEFT-text . RIGHT-text)")
746 (property-description 'type string? "one of: line, dashed-line or dotted-line") ; SYMBOL!!?
750 (define text-script-interface
752 'text-script-interface
759 (define tie-interface
762 "A tie connecting two noteheads."
764 (property-description 'staffline-clearance number? "don't get closer than this to stafflines.")
765 (property-description 'control-points list? "List of 4 offsets (number-pairs) controlling the tie shape")
766 (property-description 'heads pair? "pair of element pointers, pointing to the two heads of the tie. ")
767 (property-description 'details list? "alist of parameters for the curve shape")
768 (property-description 'thickness number? "thickness, measured in stafflinethickness")
769 (property-description 'x-gap number? "horizontal gap between notehead and tie")
770 (property-description 'direction dir? "up or down?")
771 (property-description 'minimum-length number? "minimum length in staffspace")
776 (define tie-column-interface
778 'tie-column-interface
779 "that sets tie directions in a tied chord"
783 (define volta-bracket-interface
785 'volta-bracket-interface
786 "Volta bracket with number"
788 (property-description 'bars list? "list of barline ptrs.")
789 (property-description 'thickness number? "thickness, measured in stafflinethickness")
790 (property-description 'height number? "in staffspace ")
793 (define span-bar-interface