2 custos.cc -- implement Custos
4 source file of the GNU LilyPond music typesetter
6 (C) 2000, 2002 Juergen Reuter <reuter@ipd.uka.de>
11 - merge create_ledger_line () and Note_head::create_ledger_line ()
14 - rewrite create_ledger_line () to support short and thin ledger lines
16 - do not show if a clef change immediately follows in the next line
18 - decide: do or do not print custos if the next line starts with a rest
24 #include "direction.hh"
25 #include "staff-symbol-referencer.hh"
27 #include "molecule.hh"
29 #include "note-head.hh"
31 #include "font-interface.hh"
32 #include "math.h" // rint
35 This function is a patched and hopefully much more understandable
36 rewrite of Note_head::ledger_line (). It still has some
39 (1) The term thick/2 probably should be thick*2 (probably a bug,
42 (2) The minimal width of the resulting ledger line equals the width
43 of the noteheads-ledgerending symbol (a limitation):
45 (---- left ledger ending
46 ----) right ledger ending
47 (---) resulting ledger line (just ok)
49 If x_extent ("xwid" in Note_head) is less than the width of the
50 ledger ending, the width of the total ledger line is even *greater*
51 than the width of a ledger ending (I would call this a bug). In
52 the below code, the condition "if (x_extent.length () >
53 slice_x_extent.length ())" avoids outputting the left ending in such
54 cases (rather a silly workaround, but better than nothing).
56 (---- left ledger ending
57 ----) right ledger ending
58 (-) desired ledger line
59 ------- resulting ledger line (too long)
60 ----) resulting ledger line with additional "if" (still too long)
62 The algorithm works properly only for a desired ledger line width
63 greater than the width of the ledger ending:
65 (---- left ledger ending
66 ----) right ledger ending
67 (------) desired ledger line
68 (------) resulting ledger line (ok)
70 * (3) The thickness of the ledger line is fixed (limitation).
73 Custos::create_ledger_line (Interval x_extent, Grob *me)
76 Molecule slice = Font_interface::get_default_font (me)->find_by_name ("noteheads-ledgerending");
77 Interval slice_x_extent = slice.extent (X_AXIS);
78 Interval slice_y_extent = slice.extent (Y_AXIS);
80 // Create left ending of ledger line.
81 Molecule left_ending = slice;
82 left_ending.translate_axis (x_extent[LEFT] - slice_x_extent[LEFT], X_AXIS);
83 if (x_extent.length () > slice_x_extent.length ())
84 line.add_molecule (left_ending);
86 // Create right ending of ledger line.
87 Molecule right_ending = slice;
88 right_ending.translate_axis (x_extent[RIGHT] - slice_x_extent[RIGHT],
90 line.add_molecule (right_ending);
92 // Fill out space between left and right ending of ledger line by
93 // lining up a series of slices in a row between them.
94 Molecule fill_out_slice = left_ending;
95 Real thick = slice_y_extent.length ();
96 Real delta_x = slice_x_extent.length () - thick;
97 Real xpos = x_extent [LEFT] + 2*delta_x + thick/2; // TODO: check: thick*2?
98 while (xpos <= x_extent[RIGHT])
100 fill_out_slice.translate_axis (delta_x, X_AXIS);
101 line.add_molecule (fill_out_slice);
109 Custos::add_streepjes (Grob* me,
114 // TODO: This is (almost) duplicated code (see
115 // Note_head::brew_molecule). Junk me.
116 Real inter_f = Staff_symbol_referencer::staff_space (me)/2;
117 int streepjes_i = abs (pos) < interspaces
119 : (abs (pos) - interspaces) /2;
122 Direction dir = (Direction)sign (pos);
123 Molecule ledger_line (create_ledger_line (custos_p_->extent (X_AXIS),
125 ledger_line.set_empty (true);
126 Real offs = (Staff_symbol_referencer::on_staffline (me))
129 for (int i = 0; i < streepjes_i; i++)
131 Molecule streep (ledger_line);
132 streep.translate_axis (-dir * inter_f * i * 2 + offs,
134 custos_p_->add_molecule (streep);
139 MAKE_SCHEME_CALLBACK (Custos,brew_molecule,1);
141 Custos::brew_molecule (SCM smob)
143 Item *me = (Item *)unsmob_grob (smob);
144 SCM scm_style = me->get_grob_property ("style");
146 if (gh_symbol_p (scm_style))
148 String style = ly_scm2string (scm_symbol_to_string (scm_style));
150 to_boolean (me->get_grob_property ("adjust-if-on-staffline"));
152 String idx = "custodes-" + style + "-";
155 SCM ntr_pos = me->get_grob_property ("neutral-position");
156 if (gh_number_p (ntr_pos))
157 neutral_pos = gh_scm2int (ntr_pos);
161 Direction neutral_direction =
162 to_dir (me->get_grob_property ("neutral-direction"));
164 int pos = (int)rint (Staff_symbol_referencer::position_f (me));
165 int sz = Staff_symbol_referencer::line_count (me)-1;
167 if (pos < neutral_pos)
169 else if (pos > neutral_pos)
171 else if (neutral_direction == UP)
173 else if (neutral_direction == DOWN)
175 else // auto direction; not yet supported -> use "d"
180 idx += (((pos ^ sz) & 0x1) == 0) ? "1" : "0";
188 = Font_interface::get_default_font (me)->find_by_name (idx);
189 if (molecule.empty_b ())
191 String message = "no such custos: `" + idx + "'";
192 warning (_ (message.ch_C ()));
197 add_streepjes (me, (int)pos, sz, &molecule);
198 return molecule.smobbed_copy ();
206 Custos::has_interface (Grob*m)
208 return m && m->has_interface (ly_symbol2scm ("custos-interface"));