2 stem.cc -- implement Stem
4 source file of the GNU LilyPond music typesetter
6 (c) 1996--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
7 Jan Nieuwenhuizen <janneke@gnu.org>
9 TODO: This is way too hairy
13 Stem-end, chord-start, etc. is all confusing naming.
16 #include <math.h> // rint
19 #include "directional-element-interface.hh"
20 #include "note-head.hh"
23 #include "paper-def.hh"
24 #include "rhythmic-head.hh"
25 #include "font-interface.hh"
26 #include "molecule.hh"
27 #include "paper-column.hh"
31 #include "group-interface.hh"
32 #include "staff-symbol-referencer.hh"
34 #include "side-position-interface.hh"
35 #include "dot-column.hh"
38 Stem::set_beaming (Grob*me, int beam_count, Direction d)
40 SCM pair = me->get_grob_property ("beaming");
42 if (!gh_pair_p (pair))
44 pair = gh_cons (SCM_EOL, SCM_EOL);
45 me->set_grob_property ("beaming", pair);
48 SCM l = index_get_cell (pair, d);
49 for( int i = 0; i< beam_count; i++)
51 l = gh_cons (gh_int2scm (i), l);
53 index_set_cell (pair, d, l);
58 Stem::head_positions (Grob*me)
66 Drul_array<Grob*> e (extremal_heads (me));
68 return Interval (Staff_symbol_referencer::get_position (e[DOWN]),
69 Staff_symbol_referencer::get_position (e[UP]));
74 Stem::chord_start_y (Grob*me)
76 return head_positions (me)[get_direction (me)]
77 * Staff_symbol_referencer::staff_space (me)/2.0;
81 Stem::stem_end_position (Grob*me)
83 SCM p =me->get_grob_property ("stem-end-position");
87 pos = get_default_stem_end_position (me);
88 me->set_grob_property ("stem-end-position", gh_double2scm (pos));
91 pos = gh_scm2double (p);
97 Stem::get_direction (Grob*me)
99 Direction d = Directional_element_interface::get (me);
103 d = get_default_dir (me);
105 Directional_element_interface::set (me, d);
112 Stem::set_stemend (Grob*me, Real se)
115 Direction d= get_direction (me);
117 if (d && d * head_positions (me)[get_direction (me)] >= se*d)
118 me->warning (_ ("Weird stem size; check for narrow beams"));
120 me->set_grob_property ("stem-end-position", gh_double2scm (se));
125 Note head that determines hshift for upstems
127 WARNING: triggers direction
130 Stem::support_head (Grob*me)
132 SCM h = me->get_grob_property ("support-head");
133 Grob * nh = unsmob_grob (h);
136 else if (head_count (me) == 1)
142 return unsmob_grob (ly_car (me->get_grob_property ("note-heads")));
145 return first_head (me);
150 Stem::head_count (Grob*me)
152 return Pointer_group_interface::count (me, "note-heads");
156 The note head which forms one end of the stem.
158 WARNING: triggers direction
161 Stem::first_head (Grob*me)
163 Direction d = get_direction (me);
166 return extremal_heads (me)[-d];
170 The note head opposite to the first head.
173 Stem::last_head (Grob*me)
175 Direction d = get_direction (me);
178 return extremal_heads (me)[d];
182 START is part where stem reaches `last' head.
185 Stem::extremal_heads (Grob*me)
187 const int inf = 1000000;
188 Drul_array<int> extpos;
192 Drul_array<Grob *> exthead;
193 exthead[LEFT] = exthead[RIGHT] =0;
195 for (SCM s = me->get_grob_property ("note-heads"); gh_pair_p (s); s = ly_cdr (s))
197 Grob * n = unsmob_grob (ly_car (s));
200 int p = int (Staff_symbol_referencer::get_position (n));
204 if (d* p > d* extpos[d])
209 } while (flip (&d) != DOWN);
216 icmp (int const &a, int const &b)
222 Stem::note_head_positions (Grob *me)
225 for (SCM s = me->get_grob_property ("note-heads"); gh_pair_p (s); s = ly_cdr (s))
227 Grob * n = unsmob_grob (ly_car (s));
228 int p = int (Staff_symbol_referencer::get_position (n));
239 Stem::add_head (Grob*me, Grob *n)
241 n->set_grob_property ("stem", me->self_scm ());
242 n->add_dependency (me);
244 if (Note_head::has_interface (n))
246 Pointer_group_interface::add_grob (me, ly_symbol2scm ("note-heads"), n);
251 Stem::invisible_b (Grob*me)
253 return ! (head_count (me)
254 && gh_scm2int (me->get_grob_property ("duration-log")) >= 1);
258 Stem::get_default_dir (Grob*me)
260 int staff_center = 0;
261 Interval hp = head_positions (me);
267 int udistance = (int) (UP * hp[UP] - staff_center);
268 int ddistance = (int) (DOWN* hp[DOWN] - staff_center);
270 if (sign (ddistance - udistance))
271 return Direction (sign (ddistance -udistance));
273 return to_dir (me->get_grob_property ("neutral-direction"));
277 Stem::get_default_stem_end_position (Grob*me)
279 /* Tab notation feature: make stem end extend out of staff. */
280 SCM up_to_staff = me->get_grob_property ("up-to-staff");
281 if (to_boolean (up_to_staff))
283 int line_count = Staff_symbol_referencer::line_count (me);
284 Direction dir = get_direction (me);
285 return dir * (line_count + 3.5);
288 bool grace_b = to_boolean (me->get_grob_property ("grace"));
293 SCM scm_len = me->get_grob_property ("length");
294 if (gh_number_p (scm_len))
296 length = gh_scm2double (scm_len);
300 s = me->get_grob_property ("lengths");
303 length = 2* gh_scm2double (robust_list_ref (duration_log(me) -2, s));
309 SCM sshorten = me->get_grob_property ("stem-shorten");
310 SCM scm_shorten = gh_pair_p (sshorten) ?
311 robust_list_ref ((duration_log (me) - 2) >? 0, sshorten): SCM_EOL;
312 if (gh_number_p (scm_shorten))
314 shorten = 2* gh_scm2double (scm_shorten);
320 'set-default-stemlen' sets direction too
322 Direction dir = get_direction (me);
325 dir = get_default_dir (me);
326 Directional_element_interface::set (me, dir);
329 /* On boundary: shorten only half */
330 if (abs (head_positions (me)[get_direction (me)]) <= 1)
333 /* stems in unnatural (forced) direction should be shortened,
334 according to [Roush & Gourlay] */
335 if (!chord_start_y (me)
336 || (get_direction (me) != get_default_dir (me)))
339 Interval hp = head_positions (me);
340 Real st = hp[dir] + dir * length;
343 TODO: change name to extend-stems to staff/center/'()
345 bool no_extend_b = to_boolean (me->get_grob_property ("no-stem-extend"));
346 if (!grace_b && !no_extend_b && dir * st < 0) // junkme?
350 Make a little room if we have a upflag and there is a dot.
351 previous approach was to lengthen the stem. This is not
352 good typesetting practice.
355 if (!get_beam (me) && dir == UP
356 && duration_log (me) > 2)
358 Grob * closest_to_flag = extremal_heads (me)[dir];
359 Grob * dots = closest_to_flag
360 ? Rhythmic_head::get_dots (closest_to_flag ) : 0;
364 Real dp = Staff_symbol_referencer::get_position (dots);
365 Real flagy = flag (me).extent (Y_AXIS)[-dir] * 2
366 / Staff_symbol_referencer::staff_space (me);
369 Very gory: add myself to the X-support of the parent,
370 which should be a dot-column.
372 if (dir * (st + flagy - dp) < 0.5)
374 Grob *par = dots->get_parent (X_AXIS);
376 if (Dot_column::has_interface (par))
378 Side_position_interface::add_support (par, me);
381 TODO: apply some better logic here. The flag is
382 curved inwards, so this will typically be too
398 the log of the duration (Number of hooks on the flag minus two)
401 Stem::duration_log (Grob*me)
403 SCM s = me->get_grob_property ("duration-log");
404 return (gh_number_p (s)) ? gh_scm2int (s) : 2;
408 Stem::position_noteheads (Grob*me)
410 if (!head_count (me))
413 Link_array<Grob> heads =
414 Pointer_group_interface__extract_grobs (me, (Grob*)0, "note-heads");
416 heads.sort (compare_position);
417 Direction dir =get_direction (me);
423 Real thick = gh_scm2double (me->get_grob_property ("thickness"))
424 * me->get_paper ()->get_var ("linethickness");
426 Grob *hed = support_head (me);
427 Real w = Note_head::head_extent (hed,X_AXIS)[dir];
428 for (int i=0; i < heads.size (); i++)
430 heads[i]->translate_axis (w - Note_head::head_extent (heads[i],X_AXIS)[dir],
435 int lastpos = int (Staff_symbol_referencer::get_position (heads[0]));
436 for (int i=1; i < heads.size (); i ++)
438 Real p = Staff_symbol_referencer::get_position (heads[i]);
439 int dy =abs (lastpos- (int)p);
445 Real l = Note_head::head_extent (heads[i], X_AXIS).length ();
447 Direction d = get_direction (me);
448 /* reversed head should be shifted l-thickness, but this looks
449 too crowded, so we only shift l-0.5*thickness.
450 Notice that this leads to assymetry: Normal heads overlap
451 the stem 100% whereas reversed heads only overlaps the stem
454 heads[i]->translate_axis ((l-thick*magic) * d, X_AXIS);
457 heads[i]->translate_axis (-thick*(2-magic) * d , X_AXIS);
462 For some cases we should kern some more: when the
463 distance between the next or prev note is too large, we'd
464 get large white gaps, eg.
483 MAKE_SCHEME_CALLBACK (Stem,before_line_breaking,1);
485 Stem::before_line_breaking (SCM smob)
487 Grob*me = unsmob_grob (smob);
491 Do the calculations for visible stems, but also for invisible stems
492 with note heads (i.e. half notes.)
496 stem_end_position (me); // ugh. Trigger direction calc.
497 position_noteheads (me);
501 me->set_grob_property ("molecule-callback", SCM_EOL);
504 return SCM_UNSPECIFIED;
509 When in a beam with tuplet brackets, brew_mol is called early,
510 caching a wrong value.
512 MAKE_SCHEME_CALLBACK (Stem, height, 2);
514 Stem::height (SCM smob, SCM ax)
516 Axis a = (Axis)gh_scm2int (ax);
517 Grob * me = unsmob_grob (smob);
518 assert (a == Y_AXIS);
520 SCM mol = me->get_uncached_molecule ();
523 iv = unsmob_molecule (mol)->extent (a);
524 if (Grob *b =get_beam (me))
526 Direction d = get_direction (me);
527 iv[d] += d * Beam::get_thickness (b) /2.0 ;
530 return ly_interval2scm (iv);
537 /* TODO: maybe property stroke-style should take different values,
538 e.g. "" (i.e. no stroke), "single" and "double" (currently, it's
542 SCM flag_style_scm = me->get_grob_property ("flag-style");
543 if (gh_symbol_p (flag_style_scm))
545 flag_style = ly_symbol2string (flag_style_scm);
548 if (flag_style == "no-flag")
553 bool adjust = to_boolean (me->get_grob_property ("adjust-if-on-staffline"));
555 String staffline_offs;
556 if (String::compare (flag_style, "mensural") == 0)
557 /* Mensural notation: For notes on staff lines, use different
558 flags than for notes between staff lines. The idea is that
559 flags are always vertically aligned with the staff lines,
560 regardless if the note head is on a staff line or between two
561 staff lines. In other words, the inner end of a flag always
562 touches a staff line.
567 /* Urrgh! We have to detect wether this stem ends on a staff
568 line or between two staff lines. But we can not call
569 stem_end_position(me) or get_default_stem_end_position(me),
570 since this encounters the flag and hence results in an
571 infinite recursion. However, in pure mensural notation,
572 there are no multiple note heads attached to a single stem,
573 neither is there usually need for using the stem_shorten
574 property (except for 32th and 64th notes, but that is not a
575 problem since the stem length in this case is augmented by
576 an integral multiple of staff_space). Hence, it should be
577 sufficient to just take the first note head, assume it's
578 the only one, look if it's on a staff line, and select the
579 flag's shape accordingly. In the worst case, the shape
580 looks slightly misplaced, but that will usually be the
581 programmer's fault (e.g. when trying to attach multiple
582 note heads to a single stem in mensural notation). */
585 perhaps the detection whether this correction is needed should
586 happen in a different place to avoid the recursion.
590 int p = (int)rint (Staff_symbol_referencer::get_position (first_head (me)));
591 staffline_offs = Staff_symbol_referencer::on_staffline (me, p) ?
596 staffline_offs = "2";
604 char dir = (get_direction (me) == UP) ? 'u' : 'd';
606 flag_style + to_string (dir) + staffline_offs + to_string (duration_log (me));
607 Font_metric *fm = Font_interface::get_default_font (me);
608 Molecule flag = fm->find_by_name ("flags-" + font_char);
611 me->warning (_f ("flag `%s' not found", font_char));
614 SCM stroke_style_scm = me->get_grob_property ("stroke-style");
615 if (gh_string_p (stroke_style_scm))
617 String stroke_style = ly_scm2string (stroke_style_scm);
618 if (!stroke_style.empty_b ())
620 String font_char = to_string (dir) + stroke_style;
621 Molecule stroke = fm->find_by_name ("flags-" + font_char);
622 if (stroke.empty_b ())
624 me->warning (_f ("flag stroke `%s' not found", font_char));
628 flag.add_molecule (stroke);
636 MAKE_SCHEME_CALLBACK (Stem,dim_callback,2);
638 Stem::dim_callback (SCM e, SCM ax)
640 Axis a = (Axis) gh_scm2int (ax);
641 assert (a == X_AXIS);
642 Grob *se = unsmob_grob (e);
644 if (unsmob_grob (se->get_grob_property ("beam")) || abs (duration_log (se)) <= 2)
648 r = flag (se).extent (X_AXIS);
650 return ly_interval2scm (r);
655 MAKE_SCHEME_CALLBACK (Stem,brew_molecule,1);
658 Stem::brew_molecule (SCM smob)
660 Grob*me = unsmob_grob (smob);
662 Direction d = get_direction (me);
669 This is required to avoid stems passing in tablature chords...
674 TODO: make the stem start a direction ?
676 if (to_boolean (me->get_grob_property ("avoid-note-head")))
678 Grob * lh = last_head (me);
681 y1 = Staff_symbol_referencer::get_position (lh);
685 Grob * lh = first_head (me);
688 y1 = Staff_symbol_referencer::get_position (lh);
691 Real y2 = stem_end_position (me);
693 Interval stem_y (y1 <? y2,y2 >? y1);
697 Real dy = Staff_symbol_referencer::staff_space (me) * 0.5;
699 if (Grob *hed = support_head (me))
702 must not take ledgers into account.
704 Interval head_height = Note_head::head_extent (hed,Y_AXIS);
705 Real y_attach = Note_head::stem_attachment_coordinate ( hed, Y_AXIS);
707 y_attach = head_height.linear_combination (y_attach);
708 stem_y[Direction (-d)] += d * y_attach/dy;
711 if (!invisible_b (me))
713 Real stem_width = gh_scm2double (me->get_grob_property ("thickness"))
715 * me->get_paper ()->get_var ("linethickness");
717 Molecule ss =Lookup::filledbox (Box (Interval (-stem_width/2, stem_width/2),
718 Interval (stem_y[DOWN]*dy, stem_y[UP]*dy)));
719 mol.add_molecule (ss);
722 if (!get_beam (me) && abs (duration_log (me)) > 2)
724 Molecule fl = flag (me);
725 fl.translate_axis (stem_y[d]*dy, Y_AXIS);
726 mol.add_molecule (fl);
729 return mol.smobbed_copy ();
733 move the stem to right of the notehead if it is up.
735 MAKE_SCHEME_CALLBACK (Stem,off_callback,2);
737 Stem::off_callback (SCM element_smob, SCM)
739 Grob *me = unsmob_grob (element_smob);
743 if (head_count (me) == 0)
745 return gh_double2scm (0.0);
748 if (Grob * f = first_head (me))
750 Interval head_wid = Note_head::head_extent(f, X_AXIS);
755 if (invisible_b (me))
760 attach = Note_head::stem_attachment_coordinate(f, X_AXIS);
762 Direction d = get_direction (me);
764 Real real_attach = head_wid.linear_combination (d * attach);
769 If not centered: correct for stem thickness.
774 = gh_scm2double (me->get_grob_property ("thickness"))
775 * me->get_paper ()->get_var ("linethickness");
778 r += - d * rule_thick * 0.5;
781 return gh_double2scm (r);
785 Stem::get_beam (Grob*me)
787 SCM b= me->get_grob_property ("beam");
788 return unsmob_grob (b);
792 Stem::get_stem_info (Grob *me)
794 /* Return cached info if available */
795 SCM scm_info = me->get_grob_property ("stem-info");
796 if (!gh_pair_p (scm_info))
799 scm_info = me->get_grob_property ("stem-info");
803 si.dir_ = Directional_element_interface::get (me);
804 si.ideal_y_ = gh_scm2double (gh_car (scm_info));
805 si.shortest_y_ = gh_scm2double (gh_cadr (scm_info));
810 Stem::calc_stem_info (Grob *me)
812 /* Tab notation feature: make stem end extend out of staff. */
813 SCM up_to_staff = me->get_grob_property ("up-to-staff");
814 if (to_boolean (up_to_staff))
816 int line_count = Staff_symbol_referencer::line_count (me);
817 Direction dir = get_direction (me);
818 Real ideal_y = dir * (line_count + 1.5);
819 Real shortest_y = ideal_y;
821 me->set_grob_property ("stem-info",
822 scm_list_n (gh_double2scm (ideal_y),
823 gh_double2scm (shortest_y),
828 Direction my_dir = Directional_element_interface::get (me);
829 Real staff_space = Staff_symbol_referencer::staff_space (me);
830 Grob *beam = get_beam (me);
831 Real beam_translation = Beam::get_beam_translation (beam);
832 Real beam_thickness = gh_scm2double (beam->get_grob_property ("thickness"));
833 int beam_count = Beam::get_direction_beam_count (beam, my_dir);
836 /* Simple standard stem length */
837 SCM lengths = me->get_grob_property ("beamed-lengths");
839 gh_scm2double (robust_list_ref (beam_count - 1,lengths))
842 /* stem only extends to center of beam */
843 - 0.5 * beam_thickness;
845 /* Condition: sane minimum free stem length (chord to beams) */
846 lengths = me->get_grob_property ("beamed-minimum-free-lengths");
847 Real ideal_minimum_free =
848 gh_scm2double (robust_list_ref (beam_count - 1, lengths))
853 It seems that also for ideal minimum length, we must use
854 the maximum beam count (for this direction):
856 \score{ \notes\relative c''{ [a8 a32] }}
858 must be horizontal. */
859 Real height_of_my_beams = beam_thickness
860 + (beam_count - 1) * beam_translation;
862 Real ideal_minimum_length = ideal_minimum_free
864 /* stem only extends to center of beam */
865 - 0.5 * beam_thickness;
867 ideal_length = ideal_length >? ideal_minimum_length;
870 /* Convert to Y position, calculate for dir == UP */
872 /* staff positions */
873 head_positions (me)[my_dir] * 0.5
875 Real ideal_y = note_start + ideal_length;
878 /* Conditions for Y position */
880 /* Lowest beam of (UP) beam must never be lower than second staffline
884 Although this (additional) rule is probably correct,
885 I expect that highest beam (UP) should also never be lower
886 than middle staffline, just as normal stems.
890 Obviously not for grace beams.
892 Also, not for knees. Seems to be a good thing. */
893 SCM grace = me->get_grob_property ("grace");
894 bool grace_b = to_boolean (grace);
895 bool no_extend_b = to_boolean (me->get_grob_property ("no-stem-extend"));
896 bool knee_b = to_boolean (beam->get_grob_property ("knee"));
897 if (!grace_b && !no_extend_b && !knee_b)
899 /* Highest beam of (UP) beam must never be lower than middle
901 ideal_y = ideal_y >? 0;
902 /* Lowest beam of (UP) beam must never be lower than second staffline */
903 ideal_y = ideal_y >? (-staff_space
904 - beam_thickness + height_of_my_beams);
908 SCM shorten = beam->get_grob_property ("shorten");
909 if (gh_number_p (shorten))
910 ideal_y -= gh_scm2double (shorten);
913 gh_scm2double (robust_list_ref
915 me->get_grob_property
916 ("beamed-extreme-minimum-free-lengths")))
919 Real minimum_length = minimum_free
921 /* stem only extends to center of beam */
922 - 0.5 * beam_thickness;
924 Real minimum_y = note_start + minimum_length;
928 Real shortest_y = minimum_y * my_dir;
930 me->set_grob_property ("stem-info",
931 scm_list_n (gh_double2scm (ideal_y),
932 gh_double2scm (shortest_y),
937 Stem::beam_multiplicity (Grob *stem)
939 SCM beaming= stem->get_grob_property ("beaming");
940 Slice l = int_list_to_slice (gh_car (beaming));
941 Slice r = int_list_to_slice (gh_cdr (beaming));
948 ADD_INTERFACE (Stem,"stem-interface",
950 "french-beaming up-to-staff avoid-note-head adjust-if-on-staffline thickness stem-info beamed-lengths beamed-minimum-free-lengths beamed-extreme-minimum-free-lengths lengths beam stem-shorten duration-log beaming neutral-direction stem-end-position support-head note-heads direction length flag-style no-stem-extend stroke-style");