2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2004--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
6 LilyPond is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 LilyPond is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
23 #include "note-head.hh"
24 #include "staff-symbol-referencer.hh"
25 #include "staff-symbol.hh"
28 #include "pointer-group-interface.hh"
29 #include "paper-column.hh"
31 struct Ledger_line_spanner
33 DECLARE_SCHEME_CALLBACK (print, (SCM));
34 DECLARE_SCHEME_CALLBACK (set_spacing_rods, (SCM));
35 DECLARE_GROB_INTERFACE ();
39 set_rods (Drul_array<Interval> const ¤t_extents,
40 Drul_array<Interval> const &previous_extents,
42 Item *previous_column,
43 Real min_length_fraction)
48 if (!current_extents[d].is_empty ()
49 && !previous_extents[d].is_empty ())
51 Real total_head_length = previous_extents[d].length ()
52 + current_extents[d].length ();
55 rod.distance_ = total_head_length
56 * (3 / 2 * min_length_fraction)
58 we go from right to left.
60 - previous_extents[d][LEFT]
61 + current_extents[d][RIGHT];
63 rod.item_drul_[LEFT] = current_column;
64 rod.item_drul_[RIGHT] = previous_column;
68 while (flip (&d) != DOWN);
71 MAKE_SCHEME_CALLBACK (Ledger_line_spanner, set_spacing_rods, 1);
73 Ledger_line_spanner::set_spacing_rods (SCM smob)
75 Spanner *me = dynamic_cast<Spanner *> (unsmob_grob (smob));
77 // find size of note heads.
78 Grob *staff = Staff_symbol_referencer::get_staff_symbol (me);
85 Real min_length_fraction
86 = robust_scm2double (me->get_property ("minimum-length-fraction"), 0.15);
88 Drul_array<Interval> current_extents;
89 Drul_array<Interval> previous_extents;
90 Item *previous_column = 0;
91 Item *current_column = 0;
93 Real halfspace = Staff_symbol::staff_space (staff) / 2;
95 Interval staff_extent = staff->extent (staff, Y_AXIS);
96 staff_extent *= 1 / halfspace;
99 Run through heads using a loop. Since Ledger_line_spanner can
100 contain a lot of noteheads, superlinear performance is too slow.
102 extract_item_set (me, "note-heads", heads);
103 for (vsize i = heads.size (); i--;)
107 int pos = Staff_symbol_referencer::get_rounded_position (h);
108 if (staff_extent.contains (pos))
111 Item *column = h->get_column ();
112 if (current_column != column)
114 set_rods (current_extents, previous_extents,
115 current_column, previous_column,
116 min_length_fraction);
118 previous_column = current_column;
119 current_column = column;
120 previous_extents = current_extents;
122 current_extents[DOWN].set_empty ();
123 current_extents[UP].set_empty ();
126 Interval head_extent = h->extent (column, X_AXIS);
127 Direction vdir = Direction (sign (pos));
131 current_extents[vdir].unite (head_extent);
134 if (previous_column && current_column)
135 set_rods (current_extents, previous_extents,
136 current_column, previous_column,
137 min_length_fraction);
139 return SCM_UNSPECIFIED;
142 struct Ledger_request
144 Interval ledger_extent_;
145 Interval head_extent_;
149 ledger_extent_.set_empty ();
150 head_extent_.set_empty ();
155 typedef map < int, Drul_array<Ledger_request> > Ledger_requests;
158 TODO: ledger share a lot of info. Lots of room to optimize away
159 common use of objects/variables.
161 MAKE_SCHEME_CALLBACK (Ledger_line_spanner, print, 1);
163 Ledger_line_spanner::print (SCM smob)
165 Spanner *me = dynamic_cast<Spanner *> (unsmob_grob (smob));
167 extract_grob_set (me, "note-heads", heads);
172 // find size of note heads.
173 Grob *staff = Staff_symbol_referencer::get_staff_symbol (me);
177 Real halfspace = Staff_symbol::staff_space (staff) / 2;
179 Interval staff_extent = staff->extent (staff, Y_AXIS);
180 staff_extent *= 1 / halfspace;
183 = robust_scm2double (me->get_property ("length-fraction"), 0.25);
187 Grob *common[NO_AXES];
189 for (int i = X_AXIS; i < NO_AXES; i++)
192 common[a] = common_refpoint_of_array (heads, me, a);
193 for (vsize i = heads.size (); i--;)
194 if (Grob *g = unsmob_grob (me->get_object ("accidental-grob")))
195 common[a] = common[a]->common_refpoint (g, a);
198 Ledger_requests reqs;
199 for (vsize i = heads.size (); i--;)
201 Item *h = dynamic_cast<Item *> (heads[i]);
203 int pos = Staff_symbol_referencer::get_rounded_position (h);
204 if (pos && !staff_extent.contains (pos))
206 Interval head_extent = h->extent (common[X_AXIS], X_AXIS);
207 Interval ledger_extent = head_extent;
208 ledger_extent.widen (length_fraction * head_extent.length ());
210 Direction vdir = Direction (sign (pos));
211 int rank = h->get_column ()->get_rank ();
213 reqs[rank][vdir].ledger_extent_.unite (ledger_extent);
214 reqs[rank][vdir].head_extent_.unite (head_extent);
215 reqs[rank][vdir].position_
216 = vdir * max (vdir * reqs[rank][vdir].position_, vdir * pos);
220 // determine maximum size for non-colliding ledger.
221 Real gap = robust_scm2double (me->get_property ("gap"), 0.1);
222 Ledger_requests::iterator last (reqs.end ());
223 for (Ledger_requests::iterator i (reqs.begin ());
224 i != reqs.end (); last = i++)
226 if (last == reqs.end ())
229 for (DOWN_and_UP (d))
231 if (!staff_extent.contains (last->second[d].position_)
232 && !staff_extent.contains (i->second[d].position_))
235 = (last->second[d].head_extent_[RIGHT]
236 + i->second[d].head_extent_[LEFT]) / 2;
238 for (LEFT_and_RIGHT (which))
240 Ledger_request &lr = ((which == LEFT) ? * last : *i).second[d];
242 // due tilt of quarter note-heads
245 = (!staff_extent.contains (last->second[d].position_
246 - sign (last->second[d].position_))
247 && !staff_extent.contains (i->second[d].position_
248 - sign (i->second[d].position_)));
249 Real limit = (center + (both ? which * gap / 2 : 0));
250 lr.ledger_extent_.at (-which)
251 = which * max (which * lr.ledger_extent_[-which], which * limit);
257 // create ledgers for note heads
258 Real ledgerlinethickness
259 = Staff_symbol::get_ledger_line_thickness (staff);
260 for (vsize i = heads.size (); i--;)
262 Item *h = dynamic_cast<Item *> (heads[i]);
264 int pos = Staff_symbol_referencer::get_rounded_position (h);
265 vector<Real> ledger_positions = Staff_symbol::ledger_positions (staff, pos);
266 if (!ledger_positions.empty ())
268 int ledger_count = ledger_positions.size ();
269 Interval head_size = h->extent (common[X_AXIS], X_AXIS);
270 Interval ledger_size = head_size;
271 ledger_size.widen (ledger_size.length () * length_fraction);
273 if (pos && !staff_extent.contains (pos))
275 Interval max_size = reqs[h->get_column ()->get_rank ()]
276 [Direction (sign (pos))].ledger_extent_;
278 if (!max_size.is_empty ())
279 ledger_size.intersect (max_size);
282 for (int i = 0; i < ledger_count; i++)
284 Real lpos = ledger_positions[i];
285 Interval x_extent = ledger_size;
288 if (Grob *g = unsmob_grob (h->get_object ("accidental-grob")))
290 Interval accidental_size = g->extent (common[X_AXIS], X_AXIS);
292 = linear_combination (Drul_array<Real> (accidental_size[RIGHT],
296 Real left_shorten = max (-ledger_size[LEFT] + d, 0.0);
298 x_extent[LEFT] += left_shorten;
300 TODO: shorten 2 ledger lines for the case natural +
305 Real blotdiameter = ledgerlinethickness;
307 = Interval (-0.5 * (ledgerlinethickness),
308 +0.5 * (ledgerlinethickness));
310 = Lookup::round_filled_box (Box (x_extent, y_extent), blotdiameter);
312 ledger_line.translate_axis ( lpos * halfspace, Y_AXIS);
313 ledgers.add_stencil (ledger_line);
318 ledgers.translate_axis (-me->relative_coordinate (common[X_AXIS], X_AXIS),
321 return ledgers.smobbed_copy ();
324 ADD_INTERFACE (Ledger_line_spanner,
325 "This spanner draws the ledger lines of a staff. This is a"
326 " separate grob because it has to process all potential"
327 " collisions between all note heads.",
332 "minimum-length-fraction "
337 struct Ledgered_interface
339 DECLARE_GROB_INTERFACE ();
342 ADD_INTERFACE (Ledgered_interface,
343 "Objects that need ledger lines, typically note heads. See"
344 " also @ref{ledger-line-spanner-interface}.",