2 stem.cc -- implement Stem
4 source file of the GNU LilyPond music typesetter
6 (c) 1996--2004 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"
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"
36 #include "stem-tremolo.hh"
39 Stem::set_beaming (Grob
*me
, int beam_count
, Direction d
)
41 SCM pair
= me
->get_property ("beaming");
43 if (!gh_pair_p (pair
))
45 pair
= gh_cons (SCM_EOL
, SCM_EOL
);
46 me
->set_property ("beaming", pair
);
49 SCM l
= index_get_cell (pair
, d
);
50 for (int i
= 0; i
< beam_count
; i
++)
52 l
= gh_cons (gh_int2scm (i
), l
);
54 index_set_cell (pair
, d
, l
);
59 Stem::head_positions (Grob
*me
)
67 Drul_array
<Grob
*> e (extremal_heads (me
));
69 return Interval (Staff_symbol_referencer::get_position (e
[DOWN
]),
70 Staff_symbol_referencer::get_position (e
[UP
]));
75 Stem::chord_start_y (Grob
*me
)
77 return head_positions (me
)[get_direction (me
)]
78 * Staff_symbol_referencer::staff_space (me
)/2.0;
82 Stem::stem_end_position (Grob
*me
)
84 SCM p
=me
->get_property ("stem-end-position");
88 pos
= get_default_stem_end_position (me
);
89 me
->set_property ("stem-end-position", gh_double2scm (pos
));
92 pos
= gh_scm2double (p
);
98 Stem::get_direction (Grob
*me
)
100 Direction d
= get_grob_direction (me
);
104 d
= get_default_dir (me
);
106 set_grob_direction (me
, d
);
113 Stem::set_stemend (Grob
*me
, Real se
)
116 Direction d
= get_direction (me
);
118 if (d
&& d
* head_positions (me
)[get_direction (me
)] >= se
*d
)
119 me
->warning (_ ("Weird stem size; check for narrow beams"));
121 me
->set_property ("stem-end-position", gh_double2scm (se
));
126 Note head that determines hshift for upstems
128 WARNING: triggers direction
131 Stem::support_head (Grob
*me
)
133 if (head_count (me
) == 1)
139 return unsmob_grob (ly_car (me
->get_property ("note-heads")));
142 return first_head (me
);
147 Stem::head_count (Grob
*me
)
149 return Pointer_group_interface::count (me
, "note-heads");
153 The note head which forms one end of the stem.
155 WARNING: triggers direction
158 Stem::first_head (Grob
*me
)
160 Direction d
= get_direction (me
);
163 return extremal_heads (me
)[-d
];
167 The note head opposite to the first head.
170 Stem::last_head (Grob
*me
)
172 Direction d
= get_direction (me
);
175 return extremal_heads (me
)[d
];
179 START is part where stem reaches `last' head.
182 Stem::extremal_heads (Grob
*me
)
184 const int inf
= 1000000;
185 Drul_array
<int> extpos
;
189 Drul_array
<Grob
*> exthead
;
190 exthead
[LEFT
] = exthead
[RIGHT
] =0;
192 for (SCM s
= me
->get_property ("note-heads"); gh_pair_p (s
); s
= ly_cdr (s
))
194 Grob
* n
= unsmob_grob (ly_car (s
));
197 int p
= Staff_symbol_referencer::get_rounded_position (n
);
201 if (d
* p
> d
* extpos
[d
])
206 } while (flip (&d
) != DOWN
);
213 icmp (int const &a
, int const &b
)
219 The positions, in ascending order.
222 Stem::note_head_positions (Grob
*me
)
225 for (SCM s
= me
->get_property ("note-heads"); gh_pair_p (s
); s
= ly_cdr (s
))
227 Grob
* n
= unsmob_grob (ly_car (s
));
228 int p
= Staff_symbol_referencer::get_rounded_position (n
);
239 Stem::add_head (Grob
*me
, Grob
*n
)
241 n
->set_property ("stem", me
->self_scm ());
242 n
->add_dependency (me
);
245 TODO: why not store Rest pointers?
247 if (Note_head::has_interface (n
))
249 Pointer_group_interface::add_grob (me
, ly_symbol2scm ("note-heads"), n
);
254 Stem::is_invisible (Grob
*me
)
256 return ! (head_count (me
)
257 && gh_scm2int (me
->get_property ("duration-log")) >= 1);
261 Stem::get_default_dir (Grob
*me
)
263 int staff_center
= 0;
264 Interval hp
= head_positions (me
);
270 int udistance
= (int) (UP
* hp
[UP
] - staff_center
);
271 int ddistance
= (int) (DOWN
* hp
[DOWN
] - staff_center
);
273 if (sign (ddistance
- udistance
))
274 return Direction (sign (ddistance
-udistance
));
276 return to_dir (me
->get_property ("neutral-direction"));
280 Stem::get_default_stem_end_position (Grob
*me
)
282 Real ss
= Staff_symbol_referencer::staff_space (me
);
284 int durlog
= duration_log (me
);
290 Real length
= 7; // WARNING: IN HALF SPACES
291 SCM scm_len
= me
->get_property ("length");
292 if (gh_number_p (scm_len
))
294 length
= gh_scm2double (scm_len
);
298 s
= me
->get_property ("lengths");
301 length
= 2* gh_scm2double (robust_list_ref (durlog
-2, s
));
306 'set-default-stemlen' sets direction too
308 Direction dir
= get_direction (me
);
311 dir
= get_default_dir (me
);
312 set_grob_direction (me
, dir
);
315 /* stems in unnatural (forced) direction should be shortened,
316 according to [Roush & Gourlay] */
317 if (dir
* head_positions (me
)[dir
] >= 0)
319 SCM sshorten
= me
->get_property ("stem-shorten");
320 SCM scm_shorten
= gh_pair_p (sshorten
) ?
321 robust_list_ref ((duration_log (me
) - 2) >? 0, sshorten
): SCM_EOL
;
322 Real shorten
= 2* robust_scm2double (scm_shorten
,0);
325 /* On boundary: shorten only half */
326 if (abs (head_positions (me
)[dir
]) <= 1)
335 Grob
* trem
= unsmob_grob (me
->get_property ("tremolo-flag"));
336 if (trem
&& !unsmob_grob (me
->get_property ("beam")))
339 Crude hack: add extra space if tremolo flag is there.
341 We can't do this for the beam, since we get into a loop
342 (Stem_tremolo::raw_stencil () looks at the beam.)
348 1.0 + 2 * Stem_tremolo::raw_stencil (trem
).extent (Y_AXIS
).length () / ss
;
352 Interval flag_ext
= flag (me
).extent (Y_AXIS
) ;
353 if (!flag_ext
.is_empty ())
354 minlen
+= 2 * flag_ext
.length () / ss
;
357 The clash is smaller for down stems (since the tremolo is
364 length
= length
>? (minlen
+ 1.0);
367 Interval hp
= head_positions (me
);
368 Real st
= hp
[dir
] + dir
* length
;
371 TODO: change name to extend-stems to staff/center/'()
373 bool no_extend_b
= to_boolean (me
->get_property ("no-stem-extend"));
374 if (!no_extend_b
&& dir
* st
< 0) // junkme?
378 Make a little room if we have a upflag and there is a dot.
379 previous approach was to lengthen the stem. This is not
380 good typesetting practice.
383 if (!get_beam (me
) && dir
== UP
386 Grob
* closest_to_flag
= extremal_heads (me
)[dir
];
387 Grob
* dots
= closest_to_flag
388 ? Rhythmic_head::get_dots (closest_to_flag
) : 0;
392 Real dp
= Staff_symbol_referencer::get_position (dots
);
393 Real flagy
= flag (me
).extent (Y_AXIS
)[-dir
] * 2
397 Very gory: add myself to the X-support of the parent,
398 which should be a dot-column.
400 if (dir
* (st
+ flagy
- dp
) < 0.5)
402 Grob
*par
= dots
->get_parent (X_AXIS
);
404 if (Dot_column::has_interface (par
))
406 Side_position_interface::add_support (par
, me
);
409 TODO: apply some better logic here. The flag is
410 curved inwards, so this will typically be too
426 the log of the duration (Number of hooks on the flag minus two)
429 Stem::duration_log (Grob
*me
)
431 SCM s
= me
->get_property ("duration-log");
432 return (gh_number_p (s
)) ? gh_scm2int (s
) : 2;
436 Stem::position_noteheads (Grob
*me
)
438 if (!head_count (me
))
441 Link_array
<Grob
> heads
=
442 Pointer_group_interface__extract_grobs (me
, (Grob
*)0, "note-heads");
444 heads
.sort (compare_position
);
445 Direction dir
=get_direction (me
);
451 Real thick
= thickness (me
);
453 Grob
*hed
= support_head (me
);
454 Real w
= Note_head::head_extent (hed
,X_AXIS
)[dir
];
455 for (int i
=0; i
< heads
.size (); i
++)
457 heads
[i
]->translate_axis (w
- Note_head::head_extent (heads
[i
],X_AXIS
)[dir
],
462 Real lastpos
= Real (Staff_symbol_referencer::get_position (heads
[0]));
463 for (int i
=1; i
< heads
.size (); i
++)
465 Real p
= Staff_symbol_referencer::get_position (heads
[i
]);
466 Real dy
=fabs (lastpos
- p
);
469 dy should always be 0.5, 0.0, 1.0, but provide safety margin
476 Real l
= Note_head::head_extent (heads
[i
], X_AXIS
).length ();
478 Direction d
= get_direction (me
);
480 Reversed head should be shifted l-thickness, but this
481 looks too crowded, so we only shift l-0.5*thickness.
483 This leads to assymetry: Normal heads overlap the
484 stem 100% whereas reversed heads only overlaps the
489 Real reverse_overlap
=0.5;
490 heads
[i
]->translate_axis ((l
-thick
*reverse_overlap
) * d
, X_AXIS
);
492 if (is_invisible (me
))
493 heads
[i
]->translate_axis (-thick
*(2 - reverse_overlap
) * d
, X_AXIS
);
498 For some cases we should kern some more: when the
499 distance between the next or prev note is too large, we'd
500 get large white gaps, eg.
519 MAKE_SCHEME_CALLBACK (Stem
,before_line_breaking
,1);
521 Stem::before_line_breaking (SCM smob
)
523 Grob
*me
= unsmob_grob (smob
);
527 Do the calculations for visible stems, but also for invisible stems
528 with note heads (i.e. half notes.)
532 stem_end_position (me
); // ugh. Trigger direction calc.
533 position_noteheads (me
);
537 me
->set_property ("print-function", SCM_EOL
);
540 return SCM_UNSPECIFIED
;
545 When in a beam with tuplet brackets, brew_mol is called early,
546 caching a wrong value.
548 MAKE_SCHEME_CALLBACK (Stem
, height
, 2);
550 Stem::height (SCM smob
, SCM ax
)
552 Axis a
= (Axis
)gh_scm2int (ax
);
553 Grob
* me
= unsmob_grob (smob
);
554 assert (a
== Y_AXIS
);
556 SCM mol
= me
->get_uncached_stencil ();
559 iv
= unsmob_stencil (mol
)->extent (a
);
560 if (Grob
*b
=get_beam (me
))
562 Direction d
= get_direction (me
);
563 iv
[d
] += d
* Beam::get_thickness (b
) /2.0 ;
566 return ly_interval2scm (iv
);
573 /* TODO: maybe property stroke-style should take different values,
574 e.g. "" (i.e. no stroke), "single" and "double" (currently, it's
578 SCM flag_style_scm
= me
->get_property ("flag-style");
579 if (gh_symbol_p (flag_style_scm
))
581 flag_style
= ly_symbol2string (flag_style_scm
);
584 if (flag_style
== "no-flag")
591 String staffline_offs
;
592 if (String::compare (flag_style
, "mensural") == 0)
593 /* Mensural notation: For notes on staff lines, use different
594 flags than for notes between staff lines. The idea is that
595 flags are always vertically aligned with the staff lines,
596 regardless if the note head is on a staff line or between two
597 staff lines. In other words, the inner end of a flag always
598 touches a staff line.
603 /* Urrgh! We have to detect wether this stem ends on a staff
604 line or between two staff lines. But we can not call
605 stem_end_position (me) or get_default_stem_end_position (me),
606 since this encounters the flag and hence results in an
607 infinite recursion. However, in pure mensural notation,
608 there are no multiple note heads attached to a single stem,
609 neither is there usually need for using the stem_shorten
610 property (except for 32th and 64th notes, but that is not a
611 problem since the stem length in this case is augmented by
612 an integral multiple of staff_space). Hence, it should be
613 sufficient to just take the first note head, assume it's
614 the only one, look if it's on a staff line, and select the
615 flag's shape accordingly. In the worst case, the shape
616 looks slightly misplaced, but that will usually be the
617 programmer's fault (e.g. when trying to attach multiple
618 note heads to a single stem in mensural notation).
622 perhaps the detection whether this correction is needed should
623 happen in a different place to avoid the recursion.
627 int p
= Staff_symbol_referencer::get_rounded_position (me
);
628 staffline_offs
= Staff_symbol_referencer::on_staffline (me
, p
) ?
633 staffline_offs
= "2";
641 char dir
= (get_direction (me
) == UP
) ? 'u' : 'd';
643 flag_style
+ to_string (dir
) + staffline_offs
+ to_string (duration_log (me
));
644 Font_metric
*fm
= Font_interface::get_default_font (me
);
645 Stencil flag
= fm
->find_by_name ("flags-" + font_char
);
646 if (flag
.is_empty ())
648 me
->warning (_f ("flag `%s' not found", font_char
));
651 SCM stroke_style_scm
= me
->get_property ("stroke-style");
652 if (gh_string_p (stroke_style_scm
))
654 String stroke_style
= ly_scm2string (stroke_style_scm
);
655 if (!stroke_style
.is_empty ())
657 String font_char
= to_string (dir
) + stroke_style
;
658 Stencil stroke
= fm
->find_by_name ("flags-" + font_char
);
659 if (stroke
.is_empty ())
661 me
->warning (_f ("flag stroke `%s' not found", font_char
));
665 flag
.add_stencil (stroke
);
673 MAKE_SCHEME_CALLBACK (Stem
,dim_callback
,2);
675 Stem::dim_callback (SCM e
, SCM ax
)
677 Axis a
= (Axis
) gh_scm2int (ax
);
678 assert (a
== X_AXIS
);
679 Grob
*me
= unsmob_grob (e
);
681 if (unsmob_grob (me
->get_property ("beam")) || abs (duration_log (me
)) <= 2)
685 r
= flag (me
).extent (X_AXIS
)
688 return ly_interval2scm (r
);
692 Stem::thickness (Grob
* me
)
694 return gh_scm2double (me
->get_property ("thickness"))
695 * Staff_symbol_referencer::line_thickness (me
);
698 MAKE_SCHEME_CALLBACK (Stem
,print
,1);
701 Stem::print (SCM smob
)
703 Grob
*me
= unsmob_grob (smob
);
705 Direction d
= get_direction (me
);
708 TODO: make the stem start a direction ?
710 This is required to avoid stems passing in tablature chords...
712 Grob
*lh
= to_boolean (me
->get_property ("avoid-note-head"))
713 ? last_head (me
) : lh
= first_head (me
);
718 if (is_invisible (me
))
721 Real y1
= Staff_symbol_referencer::get_position (lh
);
722 Real y2
= stem_end_position (me
);
724 Interval
stem_y (y1
<? y2
,y2
>? y1
);
728 Real dy
= Staff_symbol_referencer::staff_space (me
) * 0.5;
730 if (Grob
*hed
= support_head (me
))
733 must not take ledgers into account.
735 Interval head_height
= Note_head::head_extent (hed
,Y_AXIS
);
736 Real y_attach
= Note_head::stem_attachment_coordinate (hed
, Y_AXIS
);
738 y_attach
= head_height
.linear_combination (y_attach
);
739 stem_y
[Direction (-d
)] += d
* y_attach
/dy
;
744 Real stem_width
= thickness (me
);
746 me
->get_paper ()->get_realvar (ly_symbol2scm ("blotdiameter"));
748 Box b
= Box (Interval (-stem_width
/2, stem_width
/2),
749 Interval (stem_y
[DOWN
]*dy
, stem_y
[UP
]*dy
));
751 Stencil ss
= Lookup::round_filled_box (b
, blot
);
752 mol
.add_stencil (ss
);
754 if (!get_beam (me
) && abs (duration_log (me
)) > 2)
756 Stencil fl
= flag (me
);
757 fl
.translate_axis (stem_y
[d
]*dy
- d
* blot
/2, Y_AXIS
);
758 fl
.translate_axis (stem_width
/2, X_AXIS
);
759 mol
.add_stencil (fl
);
762 return mol
.smobbed_copy ();
766 move the stem to right of the notehead if it is up.
768 MAKE_SCHEME_CALLBACK (Stem
,off_callback
,2);
770 Stem::off_callback (SCM element_smob
, SCM
)
772 Grob
*me
= unsmob_grob (element_smob
);
776 if (head_count (me
) == 0)
778 return gh_double2scm (0.0);
781 if (Grob
* f
= first_head (me
))
783 Interval head_wid
= Note_head::head_extent (f
, X_AXIS
);
787 if (is_invisible (me
))
792 attach
= Note_head::stem_attachment_coordinate (f
, X_AXIS
);
794 Direction d
= get_direction (me
);
796 Real real_attach
= head_wid
.linear_combination (d
* attach
);
801 If not centered: correct for stem thickness.
808 r
+= - d
* rule_thick
* 0.5;
811 return gh_double2scm (r
);
816 Stem::get_beam (Grob
*me
)
818 SCM b
= me
->get_property ("beam");
819 return unsmob_grob (b
);
823 Stem::get_stem_info (Grob
*me
)
825 /* Return cached info if available */
826 SCM scm_info
= me
->get_property ("stem-info");
827 if (!gh_pair_p (scm_info
))
830 scm_info
= me
->get_property ("stem-info");
834 si
.dir_
= get_grob_direction (me
);
835 si
.ideal_y_
= gh_scm2double (gh_car (scm_info
));
836 si
.shortest_y_
= gh_scm2double (gh_cadr (scm_info
));
842 TODO: add extra space for tremolos!
845 Stem::calc_stem_info (Grob
*me
)
847 Direction my_dir
= get_grob_direction (me
);
851 programming_error ("No stem dir set?");
855 Real staff_space
= Staff_symbol_referencer::staff_space (me
);
856 Grob
*beam
= get_beam (me
);
857 Real beam_translation
= Beam::get_beam_translation (beam
);
858 Real beam_thickness
= Beam::get_thickness (beam
);
859 int beam_count
= Beam::get_direction_beam_count (beam
, my_dir
);
862 /* Simple standard stem length */
863 SCM lengths
= me
->get_property ("beamed-lengths");
865 gh_scm2double (robust_list_ref (beam_count
- 1,lengths
))
868 /* stem only extends to center of beam */
869 - 0.5 * beam_thickness
;
871 /* Condition: sane minimum free stem length (chord to beams) */
872 lengths
= me
->get_property ("beamed-minimum-free-lengths");
873 Real ideal_minimum_free
=
874 gh_scm2double (robust_list_ref (beam_count
- 1, lengths
))
879 It seems that also for ideal minimum length, we must use
880 the maximum beam count (for this direction):
882 \score{ \notes\relative c''{ [a8 a32] }}
884 must be horizontal. */
885 Real height_of_my_beams
= beam_thickness
886 + (beam_count
- 1) * beam_translation
;
888 Real ideal_minimum_length
= ideal_minimum_free
890 /* stem only extends to center of beam */
891 - 0.5 * beam_thickness
;
893 ideal_length
= ideal_length
>? ideal_minimum_length
;
896 /* Convert to Y position, calculate for dir == UP */
898 /* staff positions */
899 head_positions (me
)[my_dir
] * 0.5
900 * my_dir
* staff_space
;
901 Real ideal_y
= note_start
+ ideal_length
;
904 /* Conditions for Y position */
906 /* Lowest beam of (UP) beam must never be lower than second staffline
910 Although this (additional) rule is probably correct,
911 I expect that highest beam (UP) should also never be lower
912 than middle staffline, just as normal stems.
916 Obviously not for grace beams.
918 Also, not for knees. Seems to be a good thing. */
919 bool no_extend_b
= to_boolean (me
->get_property ("no-stem-extend"));
920 bool is_knee
= to_boolean (beam
->get_property ("knee"));
921 if (!no_extend_b
&& !is_knee
)
923 /* Highest beam of (UP) beam must never be lower than middle
925 ideal_y
= ideal_y
>? 0;
926 /* Lowest beam of (UP) beam must never be lower than second staffline */
927 ideal_y
= ideal_y
>? (-staff_space
928 - beam_thickness
+ height_of_my_beams
);
932 ideal_y
-= robust_scm2double (beam
->get_property ("shorten"), 0);
935 gh_scm2double (robust_list_ref
938 ("beamed-extreme-minimum-free-lengths")))
941 Real minimum_length
= minimum_free
943 /* stem only extends to center of beam */
944 - 0.5 * beam_thickness
;
946 Real minimum_y
= note_start
+ minimum_length
;
950 Real shortest_y
= minimum_y
* my_dir
;
952 me
->set_property ("stem-info",
953 scm_list_n (gh_double2scm (ideal_y
),
954 gh_double2scm (shortest_y
),
959 Stem::beam_multiplicity (Grob
*stem
)
961 SCM beaming
= stem
->get_property ("beaming");
962 Slice l
= int_list_to_slice (gh_car (beaming
));
963 Slice r
= int_list_to_slice (gh_cdr (beaming
));
971 these are too many props.
973 ADD_INTERFACE (Stem
,"stem-interface",
974 "The stem represent the graphical stem. "
975 " In addition, it internally connects note heads, beams, tremolos. Rests "
976 " and whole notes have invisible stems."
980 "tremolo-flag french-beaming "
981 "avoid-note-head thickness "
982 "stem-info beamed-lengths beamed-minimum-free-lengths "
983 "beamed-extreme-minimum-free-lengths lengths beam stem-shorten "
984 "duration-log beaming neutral-direction stem-end-position "
985 "note-heads direction length flag-style "
986 "no-stem-extend stroke-style");
990 /****************************************************************/
992 Stem_info::Stem_info ()
994 ideal_y_
= shortest_y_
=0;
999 Stem_info::scale (Real x
)