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>
14 #include "note-head.hh"
15 #include "staff-symbol-referencer.hh"
16 #include "staff-symbol.hh"
19 #include "group-interface.hh"
20 #include "paper-column.hh"
22 struct Ledger_line_spanner
24 DECLARE_SCHEME_CALLBACK (print, (SCM ));
25 DECLARE_SCHEME_CALLBACK (set_spacing_rods, (SCM ));
26 static Stencil brew_ledger_lines (Grob *me,
33 static bool has_interface (Grob*);
38 Ledger_line_spanner::brew_ledger_lines (Grob *staff,
42 Real ledgerlinethickness,
46 int line_count = ((abs (pos) < interspaces)
48 : (abs (pos) - interspaces) / 2);
52 Real blotdiameter = ledgerlinethickness;
54 Interval (-0.5*(ledgerlinethickness),
55 +0.5*(ledgerlinethickness));
56 Stencil proto_ledger_line =
57 Lookup::round_filled_box (Box (x_extent, y_extent), blotdiameter);
59 x_extent[LEFT] += left_shorten;
60 Stencil proto_first_line =
61 Lookup::round_filled_box (Box (x_extent, y_extent), blotdiameter);
63 Direction dir = (Direction)sign (pos);
64 Real offs = (Staff_symbol_referencer::on_staffline (staff, pos))
69 offs += pos * halfspace;
70 for (int i = 0; i < line_count; i++)
72 Stencil ledger_line ((i == 0)
76 ledger_line.translate_axis (-dir * halfspace * i * 2 + offs, Y_AXIS);
77 stencil.add_stencil (ledger_line);
85 typedef std::map<int, Drul_array<Interval> > Head_extents_map;
86 typedef std::map<int, Grob*> Column_map;
88 MAKE_SCHEME_CALLBACK (Ledger_line_spanner, set_spacing_rods, 1);
90 Ledger_line_spanner::set_spacing_rods (SCM smob)
92 Spanner *me = dynamic_cast<Spanner*> (unsmob_grob (smob));
94 // find size of note heads.
95 Grob * staff = Staff_symbol_referencer::get_staff_symbol (me);
99 Link_array<Grob> heads (extract_grob_array (me, ly_symbol2scm ("note-heads")));
101 if (heads.is_empty ())
104 Real min_length_fraction
105 = robust_scm2double (me->get_property ("minimum-length-fraction"), 0.15);
107 Head_extents_map head_extents;
110 int interspaces = Staff_symbol::line_count (staff)-1;
111 for (int i = heads.size (); i--; )
113 Item *h = dynamic_cast<Item*> (heads[i]);
115 int pos = Staff_symbol_referencer::get_rounded_position (h);
117 && abs (pos) > interspaces)
119 Grob *column = h->get_column ();
120 int rank = Paper_column::get_rank (column);
122 Interval head_extent = h->extent (column, X_AXIS);
123 Direction vdir = Direction (sign (pos));
127 Interval prev_extent;
129 Head_extents_map::iterator j = head_extents.find (rank);
130 if (j != head_extents.end ())
131 prev_extent = (*j).second[vdir];
133 columns[rank] = column;
135 prev_extent.unite (head_extent);
136 head_extents[rank][vdir] = prev_extent;
140 for (Column_map::const_iterator c (columns.begin()); c != columns.end(); c++)
142 Grob *column = (*c).second;
143 int rank = (*c).first;
145 int next_rank = rank + 2;
147 if (head_extents.find (next_rank) != head_extents.end ())
149 Drul_array<Interval> extents_left = head_extents[rank];
150 Drul_array<Interval> extents_right = head_extents[next_rank];
155 if (!extents_right[d].is_empty () && !extents_right[d].is_empty ())
157 Real l1 = extents_right[d].length() * min_length_fraction;
158 Real l2 = extents_left[d].length() * min_length_fraction;
161 rod.distance_ = l1 + l2 + (l1+ l2)/2.0
162 + extents_left[d][RIGHT]
163 - extents_right[d][LEFT];
165 rod.item_drul_[LEFT] = dynamic_cast<Item*> (column);
166 rod.item_drul_[RIGHT] = dynamic_cast<Item*> (columns[next_rank]);
170 while (flip (&d) != DOWN);
174 return SCM_UNSPECIFIED;
178 struct Ledger_request
180 Interval ledger_extent_;
181 Interval head_extent_;
185 ledger_extent_.set_empty ();
186 head_extent_.set_empty ();
191 typedef std::map<int, Drul_array<Ledger_request> > Ledger_requests;
195 TODO: ledger share a lot of info. Lots of room to optimize away common
196 use of objects/variables.
198 MAKE_SCHEME_CALLBACK (Ledger_line_spanner, print, 1);
200 Ledger_line_spanner::print (SCM smob)
202 Spanner *me = dynamic_cast<Spanner*> (unsmob_grob (smob));
203 Link_array<Grob> heads (extract_grob_array (me, ly_symbol2scm ("note-heads")));
205 if (heads.is_empty ())
208 // find size of note heads.
209 Grob * staff = Staff_symbol_referencer::get_staff_symbol (me);
215 = robust_scm2double (me->get_property ("length-fraction"), 0.25);
218 Stencil default_ledger;
220 Grob * common[NO_AXES];
222 for (int i = X_AXIS; i < NO_AXES; i++)
225 common[a] = common_refpoint_of_array (heads, me, a);
226 for (int i = heads.size (); i--; )
227 if (Grob * g = unsmob_grob (me->get_property ("accidental-grob")))
228 common[a] = common[a]->common_refpoint (g, a);
231 int interspaces = Staff_symbol::line_count (staff)-1;
232 Ledger_requests reqs;
233 for (int i = heads.size (); i--; )
235 Item *h = dynamic_cast<Item*> (heads[i]);
237 int pos = Staff_symbol_referencer::get_rounded_position (h);
239 && abs (pos) > interspaces)
241 Interval head_extent = h->extent (common[X_AXIS], X_AXIS);
242 Interval ledger_extent = head_extent;
243 ledger_extent.widen (length_fraction * head_extent.length ());
245 Direction vdir = Direction (sign (pos));
246 int rank = Paper_column::get_rank (h->get_column ());
248 reqs[rank][vdir].ledger_extent_.unite (ledger_extent);
249 reqs[rank][vdir].head_extent_.unite (head_extent);
250 reqs[rank][vdir].position_ =
251 vdir * ((vdir* reqs[rank][vdir].position_) >? (vdir *pos));
255 // determine maximum size for non-colliding ledger.
256 Real gap = robust_scm2double (me->get_property ("gap"), 0.1);
257 Ledger_requests::iterator last (reqs.end ());
258 for (Ledger_requests::iterator i (reqs.begin ());
259 i != reqs.end (); last = i++)
261 if (last == reqs.end ())
269 if (abs (last->second[d].position_) > interspaces
270 && abs (i->second[d].position_) > interspaces)
273 (last->second[d].head_extent_[RIGHT]
274 + i->second[d].head_extent_[LEFT] )/2;
276 Direction which = LEFT;
279 Ledger_request &lr = ((which == LEFT) ? *last : *i).second[d];
281 // due tilt of quarter note-heads
283 (abs (last->second[d].position_) > interspaces + 1
284 && abs (i->second[d].position_) > interspaces + 1);
286 Real limit = (center + (both? which * gap/2 : 0));
287 lr.ledger_extent_.elem_ref (-which)
288 = which * (which * lr.ledger_extent_[-which] >? which * limit);
290 while (flip (&which) != LEFT);
293 while (flip (&d) != DOWN);
296 // create ledgers for note heads
297 Real ledgerlinethickness =
298 Staff_symbol::get_ledger_line_thickness (staff);
299 Real halfspace = Staff_symbol::staff_space (staff)/2;
300 for (int i = heads.size (); i--; )
302 Item *h = dynamic_cast<Item*> (heads[i]);
304 int pos = Staff_symbol_referencer::get_rounded_position (h);
305 if (abs (pos) > interspaces + 1)
307 Interval head_size = h->extent (common[X_AXIS], X_AXIS);
308 Interval ledger_size = head_size;
309 ledger_size.widen (ledger_size.length ()* length_fraction);
311 Interval max_size = reqs[Paper_column::get_rank (h->get_column ())][Direction (sign(pos))].ledger_extent_;
313 ledger_size.intersect (max_size);
314 Real left_shorten = 0.0;
315 if (Grob * g = unsmob_grob (h->get_property ("accidental-grob")))
317 Interval accidental_size = g->extent (common[X_AXIS], X_AXIS);
319 linear_combination (Drul_array<Real> (accidental_size[RIGHT],
323 left_shorten = (-ledger_size[LEFT] + d) >? 0 ;
326 TODO: shorten 2 ledger lines for the case natural +
332 ledgers.add_stencil (brew_ledger_lines (staff, pos, interspaces,
340 ledgers.translate_axis (-me->relative_coordinate (common[X_AXIS], X_AXIS),
343 return ledgers.smobbed_copy ();
346 ADD_INTERFACE (Ledger_line_spanner,
347 "ledger-line-interface",
348 "This spanner draws the ledger lines of a staff, for note heads that stick out. ",
349 "note-heads thickness minimum-length-fraction length-fraction gap");
352 struct Ledgered_interface {
353 static bool has_interface (Grob*);
356 ADD_INTERFACE (Ledgered_interface,
357 "ledgered-interface",
358 "Objects that need ledger lines.",