2 ledger-line-spanner.cc -- implement Ledger_line_spanner
4 source file of the GNU LilyPond music typesetter
6 (c) 2004--2005 Han-Wen Nienhuys <hanwen@xs4all.nl>
13 #include "note-head.hh"
14 #include "staff-symbol-referencer.hh"
15 #include "staff-symbol.hh"
18 #include "group-interface.hh"
19 #include "paper-column.hh"
21 struct Ledger_line_spanner
23 DECLARE_SCHEME_CALLBACK (print, (SCM));
24 DECLARE_SCHEME_CALLBACK (set_spacing_rods, (SCM));
25 static Stencil brew_ledger_lines (Grob *me,
32 static bool has_interface (Grob *);
36 Ledger_line_spanner::brew_ledger_lines (Grob *staff,
40 Real ledgerlinethickness,
44 int line_count = ((abs (pos) < interspaces)
46 : (abs (pos) - interspaces) / 2);
50 Real blotdiameter = ledgerlinethickness;
52 = Interval (-0.5* (ledgerlinethickness),
53 +0.5* (ledgerlinethickness));
54 Stencil proto_ledger_line
55 = Lookup::round_filled_box (Box (x_extent, y_extent), blotdiameter);
57 x_extent[LEFT] += left_shorten;
58 Stencil proto_first_line
59 = Lookup::round_filled_box (Box (x_extent, y_extent), blotdiameter);
61 Direction dir = (Direction)sign (pos);
62 Real offs = (Staff_symbol_referencer::on_staffline (staff, pos))
66 offs += pos * halfspace;
67 for (int i = 0; i < line_count; i++)
69 Stencil ledger_line ((i == 0)
72 ledger_line.translate_axis (-dir * halfspace * i * 2 + offs, Y_AXIS);
73 stencil.add_stencil (ledger_line);
80 typedef std::map < int, Drul_array<Interval> > Head_extents_map;
81 typedef std::map < int, Grob *> Column_map;
83 MAKE_SCHEME_CALLBACK (Ledger_line_spanner, set_spacing_rods, 1);
85 Ledger_line_spanner::set_spacing_rods (SCM smob)
87 Spanner *me = dynamic_cast<Spanner *> (unsmob_grob (smob));
89 // find size of note heads.
90 Grob *staff = Staff_symbol_referencer::get_staff_symbol (me);
94 Link_array<Grob> heads (extract_grob_array (me, ly_symbol2scm ("note-heads")));
96 if (heads.is_empty ())
99 Real min_length_fraction
100 = robust_scm2double (me->get_property ("minimum-length-fraction"), 0.15);
102 Head_extents_map head_extents;
105 int interspaces = Staff_symbol::line_count (staff) - 1;
106 for (int i = heads.size (); i--;)
108 Item *h = dynamic_cast<Item *> (heads[i]);
110 int pos = Staff_symbol_referencer::get_rounded_position (h);
112 && abs (pos) > interspaces)
114 Grob *column = h->get_column ();
115 int rank = Paper_column::get_rank (column);
117 Interval head_extent = h->extent (column, X_AXIS);
118 Direction vdir = Direction (sign (pos));
122 Interval prev_extent;
124 Head_extents_map::iterator j = head_extents.find (rank);
125 if (j != head_extents.end ())
126 prev_extent = (*j).second[vdir];
128 columns[rank] = column;
130 prev_extent.unite (head_extent);
131 head_extents[rank][vdir] = prev_extent;
135 for (Column_map::const_iterator c (columns.begin ()); c != columns.end (); c++)
137 Grob *column = (*c).second;
138 int rank = (*c).first;
140 int next_rank = rank + 2;
142 if (head_extents.find (next_rank) != head_extents.end ())
144 Drul_array<Interval> extents_left = head_extents[rank];
145 Drul_array<Interval> extents_right = head_extents[next_rank];
150 if (!extents_left[d].is_empty () && !extents_right[d].is_empty ())
152 Real l1 = extents_right[d].length () * min_length_fraction;
153 Real l2 = extents_left[d].length () * min_length_fraction;
156 rod.distance_ = l1 + l2 + (l1+ l2) / 2.0
157 + extents_left[d][RIGHT]
158 - extents_right[d][LEFT];
160 rod.item_drul_[LEFT] = dynamic_cast<Item *> (column);
161 rod.item_drul_[RIGHT] = dynamic_cast<Item *> (columns[next_rank]);
165 while (flip (&d) != DOWN);
169 return SCM_UNSPECIFIED;
172 struct Ledger_request
174 Interval ledger_extent_;
175 Interval head_extent_;
180 ledger_extent_.set_empty ();
181 head_extent_.set_empty ();
186 typedef std::map < int, Drul_array<Ledger_request> > Ledger_requests;
189 TODO: ledger share a lot of info. Lots of room to optimize away common
190 use of objects/variables.
192 MAKE_SCHEME_CALLBACK (Ledger_line_spanner, print, 1);
194 Ledger_line_spanner::print (SCM smob)
196 Spanner *me = dynamic_cast<Spanner *> (unsmob_grob (smob));
197 Link_array<Grob> heads (extract_grob_array (me, ly_symbol2scm ("note-heads")));
199 if (heads.is_empty ())
202 // find size of note heads.
203 Grob *staff = Staff_symbol_referencer::get_staff_symbol (me);
208 = robust_scm2double (me->get_property ("length-fraction"), 0.25);
211 Stencil default_ledger;
213 Grob *common[NO_AXES];
215 for (int i = X_AXIS; i < NO_AXES; i++)
218 common[a] = common_refpoint_of_array (heads, me, a);
219 for (int i = heads.size (); i--;)
220 if (Grob *g = unsmob_grob (me->get_property ("accidental-grob")))
221 common[a] = common[a]->common_refpoint (g, a);
224 int interspaces = Staff_symbol::line_count (staff) - 1;
225 Ledger_requests reqs;
226 for (int i = heads.size (); i--;)
228 Item *h = dynamic_cast<Item *> (heads[i]);
230 int pos = Staff_symbol_referencer::get_rounded_position (h);
232 && abs (pos) > interspaces)
234 Interval head_extent = h->extent (common[X_AXIS], X_AXIS);
235 Interval ledger_extent = head_extent;
236 ledger_extent.widen (length_fraction * head_extent.length ());
238 Direction vdir = Direction (sign (pos));
239 int rank = Paper_column::get_rank (h->get_column ());
241 reqs[rank][vdir].ledger_extent_.unite (ledger_extent);
242 reqs[rank][vdir].head_extent_.unite (head_extent);
243 reqs[rank][vdir].position_
244 = vdir * ((vdir* reqs[rank][vdir].position_) >? (vdir *pos));
248 // determine maximum size for non-colliding ledger.
249 Real gap = robust_scm2double (me->get_property ("gap"), 0.1);
250 Ledger_requests::iterator last (reqs.end ());
251 for (Ledger_requests::iterator i (reqs.begin ());
252 i != reqs.end (); last = i++)
254 if (last == reqs.end ())
262 if (abs (last->second[d].position_) > interspaces
263 && abs (i->second[d].position_) > interspaces)
266 = (last->second[d].head_extent_[RIGHT]
267 + i->second[d].head_extent_[LEFT]) / 2;
269 Direction which = LEFT;
272 Ledger_request &lr = ((which == LEFT) ? *last : *i).second[d];
274 // due tilt of quarter note-heads
276 = (abs (last->second[d].position_) > interspaces + 1
277 && abs (i->second[d].position_) > interspaces + 1);
279 Real limit = (center + (both? which * gap / 2 : 0));
280 lr.ledger_extent_.elem_ref (-which)
281 = which * (which * lr.ledger_extent_[-which] >? which * limit);
283 while (flip (&which) != LEFT);
286 while (flip (&d) != DOWN);
289 // create ledgers for note heads
290 Real ledgerlinethickness
291 = Staff_symbol::get_ledger_line_thickness (staff);
292 Real halfspace = Staff_symbol::staff_space (staff) / 2;
293 for (int i = heads.size (); i--;)
295 Item *h = dynamic_cast<Item *> (heads[i]);
297 int pos = Staff_symbol_referencer::get_rounded_position (h);
298 if (abs (pos) > interspaces + 1)
300 Interval head_size = h->extent (common[X_AXIS], X_AXIS);
301 Interval ledger_size = head_size;
302 ledger_size.widen (ledger_size.length ()* length_fraction);
304 Interval max_size = reqs[Paper_column::get_rank (h->get_column ())][Direction (sign (pos))].ledger_extent_;
306 ledger_size.intersect (max_size);
307 Real left_shorten = 0.0;
308 if (Grob *g = unsmob_grob (h->get_property ("accidental-grob")))
310 Interval accidental_size = g->extent (common[X_AXIS], X_AXIS);
312 = linear_combination (Drul_array<Real> (accidental_size[RIGHT],
316 left_shorten = (-ledger_size[LEFT] + d) >? 0;
319 TODO: shorten 2 ledger lines for the case natural +
325 ledgers.add_stencil (brew_ledger_lines (staff, pos, interspaces,
333 ledgers.translate_axis (-me->relative_coordinate (common[X_AXIS], X_AXIS),
336 return ledgers.smobbed_copy ();
339 ADD_INTERFACE (Ledger_line_spanner,
340 "ledger-line-interface",
341 "This spanner draws the ledger lines of a staff, for note heads that stick out. ",
342 "note-heads thickness minimum-length-fraction length-fraction gap");
344 struct Ledgered_interface
346 static bool has_interface (Grob *);
349 ADD_INTERFACE (Ledgered_interface,
350 "ledgered-interface",
351 "Objects that need ledger lines.",