2 tie.cc -- implement Tie
4 source file of the GNU LilyPond music typesetter
6 (c) 1997--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
12 #include "paper-def.hh"
14 #include "rhythmic-head.hh"
16 #include "paper-column.hh"
18 #include "staff-symbol-referencer.hh"
19 #include "directional-element-interface.hh"
20 #include "molecule.hh"
21 #include "bezier-bow.hh"
23 #include "note-head.hh"
26 tie: Connect two noteheads.
30 c4 ~ \clef bass ; c4 or
34 do we have non-horizontal ties then?
39 Tie::set_head (Score_element*me,Direction d, Item * head_l)
41 assert (!head (me,d));
42 index_set_cell (me->get_elt_property ("heads"), d, head_l->self_scm ());
44 dynamic_cast<Spanner*> (me)->set_bound (d, head_l);
45 me->add_dependency (head_l);
49 Tie::set_interface (Score_element*me)
51 me->set_elt_property ("heads", gh_cons (SCM_EOL, SCM_EOL));
52 me->set_interface (ly_symbol2scm ("tie-interface"));
56 Tie::has_interface (Score_element*me)
58 return me->has_interface (ly_symbol2scm ("tie-interface"));
62 Tie::head (Score_element*me, Direction d)
64 SCM c = me->get_elt_property ("heads");
65 c = index_cell (c, d);
67 return unsmob_element (c);
71 Tie::position_f (Score_element*me)
73 Direction d = head (me,LEFT) ? LEFT:RIGHT;
74 return Staff_symbol_referencer::position_f (head (me,d));
79 The direction of the Tie is more complicated (See [Ross] p136 and
80 further), the case of multiple ties is handled by Tie_column.
83 Tie::get_default_dir (Score_element*me)
85 Item * sl = head(me,LEFT) ? Rhythmic_head::stem_l (head (me,LEFT)) :0;
86 Item * sr = head(me,RIGHT) ? Rhythmic_head::stem_l (head (me,RIGHT)) :0;
91 if (Directional_element_interface (sl).get () == UP
92 && Directional_element_interface (sr).get () == UP)
97 Item *s = sl ? sl : sr;
98 return - Directional_element_interface (s). get ();
107 Tie::get_control_points (SCM smob)
109 Spanner*me = dynamic_cast<Spanner*> (unsmob_element (smob));
110 Direction headdir = CENTER;
113 else if (head(me,RIGHT))
117 programming_error ("Tie without heads.");
119 return SCM_UNSPECIFIED;
122 if (!Directional_element_interface (me).get ())
123 Directional_element_interface (me).set (Tie::get_default_dir (me));
125 Real staff_space = Staff_symbol_referencer::staff_space (me);
127 Real x_gap_f = me->paper_l ()->get_var ("tie_x_gap");
129 Score_element* commonx = me->common_refpoint (me->get_bound (LEFT), X_AXIS);
130 commonx = me->common_refpoint (me->get_bound (RIGHT), X_AXIS);
132 Score_element* l = me->get_bound (LEFT);
133 Score_element* r = me->get_bound (RIGHT);
136 if (Note_head::has_interface (me->get_bound (LEFT)))
137 left_x = l->extent (X_AXIS)[RIGHT] + x_gap_f;
139 left_x = l->extent (X_AXIS).length () / 2;
142 if (Note_head::has_interface (me->get_bound (LEFT))
143 && Note_head::has_interface (me->get_bound (RIGHT)))
145 width = r->relative_coordinate (commonx, X_AXIS)
146 + r->extent (X_AXIS)[LEFT]
147 - l->relative_coordinate (commonx, X_AXIS)
148 - l->extent (X_AXIS)[RIGHT]
153 if (Note_head::has_interface (me->get_bound (LEFT)))
154 width = r->relative_coordinate (commonx, X_AXIS)
155 - l->relative_coordinate (commonx, X_AXIS)
156 - l->extent (X_AXIS)[RIGHT]
159 width = r->relative_coordinate (commonx, X_AXIS)
160 - l->extent (X_AXIS).length () / 2
161 + r->extent (X_AXIS)[LEFT]
162 - l->relative_coordinate (commonx, X_AXIS)
166 Direction dir = Directional_element_interface (me).get();
168 Real h_inf = me->paper_l ()->get_var ("tie_height_limit_factor") * staff_space;
169 Real r_0 = me->paper_l ()->get_var ("tie_ratio");
172 Bezier b = slur_shape (width, h_inf, r_0);
174 Offset leave_dir = b.control_[1] - b.control_[0];
176 Real dx = (head (me, headdir)->extent (X_AXIS).length () + x_gap_f)/2.0;
177 Real max_gap = leave_dir[Y_AXIS] * dx / leave_dir[X_AXIS];
180 for small ties (t small) we want to start in the Y-center (so dy = 0), for
181 large ties, the tie should appear to come from the center of the
182 head, so dy = max_gap
184 maybe use a different formula?
186 TODO: what if 2 heads have different size.
188 TODO: for small ties, it is better to start over the heads
189 iso. next to the heads.
191 Real t = (width / staff_space - 5.0); // ugh.
192 Real dy = t > 0 ? max_gap * sqr (t / (1 + t)) : 0.0;
194 Real ypos = Tie::position_f (me) * staff_space/2 + dir * dy;
197 todo: prevent ending / staffline collision.
199 todo: tie / stem collision
202 b = slur_shape(width,h_inf, r_0);
204 b.translate (Offset (left_x, ypos));
208 Avoid colliding of the horizontal part with stafflines.
210 should do me for slurs as well.
213 Array<Real> horizontal (b.solve_derivative (Offset (1,0)));
214 if (horizontal.size ())
217 ugh. Doesnt work for non-horizontal curves.
219 Real y = b.curve_point (horizontal[0])[Y_AXIS];
221 Real ry = rint (y/staff_space) * staff_space;
224 if (fabs (y) <= Staff_symbol_referencer::staff_radius (me)
225 && fabs (diff) < me->paper_l ()->get_var ("tie_staffline_clearance"))
227 newy = ry - 0.5 * staff_space * sign (diff) ;
230 Real y0 = b.control_ [0][Y_AXIS];
231 b.control_[2][Y_AXIS] =
232 b.control_[1][Y_AXIS] =
233 (b.control_[1][Y_AXIS] - y0) * ((newy - y0) / (y - y0)) + y0;
236 programming_error ("Tie is nowhere horizontal");
240 SCM controls = SCM_EOL;
242 controls = gh_cons ( ly_offset2scm (b.control_[i]), controls);
246 MAKE_SCHEME_CALLBACK(Tie,set_spacing_rods);
249 TODO: set minimum distances for begin/end of line
252 Tie::set_spacing_rods (SCM smob)
254 Score_element*me = unsmob_element (smob);
255 Spanner*sp = dynamic_cast<Spanner*> (me);
258 r.item_l_drul_ [LEFT]=sp->get_bound (LEFT);
259 r.item_l_drul_ [RIGHT]=sp->get_bound (RIGHT);
262 = gh_scm2double (me->get_elt_property ("minimum-length"))
263 * me->paper_l ()->get_var ("staffspace");
265 return SCM_UNSPECIFIED;
268 MAKE_SCHEME_CALLBACK(Tie,brew_molecule);
270 Tie::brew_molecule (SCM smob)
272 Score_element*me = unsmob_element (smob);
274 SCM cp = me->get_elt_property ("control-points");
277 cp = get_control_points (smob);
278 me->set_elt_property ("control-points", cp);
282 gh_scm2double (me->get_elt_property ("thickness"))
283 * me->paper_l ()->get_var ("stafflinethickness");
287 for (SCM s= cp; s != SCM_EOL; s = gh_cdr (s))
289 b.control_[i] = ly_scm2offset (gh_car (s));
293 Molecule a = me->lookup_l ()->slur (b, Directional_element_interface (me).get () * thick, thick);
295 return a.create_scheme ();