2 break-align-item.cc -- implement Break_align_item
4 source file of the GNU LilyPond music typesetter
6 (c) 1997--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
10 #include "side-position-interface.hh"
12 #include "dimension-cache.hh"
13 #include "lily-guile.hh"
14 #include "break-align-item.hh"
15 #include "dimensions.hh"
16 #include "paper-score.hh"
17 #include "paper-def.hh"
18 #include "paper-column.hh"
19 #include "group-interface.hh"
22 Handle spacing for prefatory matter.
24 TODO: rewrite this. It is kludgy
28 Break_align_item::before_line_breaking ()
30 Direction ad = (break_status_dir() == LEFT) ? RIGHT : LEFT;
31 Real interline= paper_l ()->get_var ("interline");
33 set_elt_property ("self-alignment-X", gh_int2scm (ad));
36 Link_array<Score_element> elems;
37 Link_array<Score_element> all_elems
38 = Group_interface__extract_elements (this, (Score_element*)0,
41 for (int i=0; i < all_elems.size(); i++)
43 Interval y = all_elems[i]->extent(axis ());
45 elems.push (dynamic_cast<Score_element*> (all_elems[i]));
51 SCM symbol_list = SCM_EOL;
53 SCM current_origin = ly_str02scm ("");
54 for (int i=0; i <= elems.size (); i++)
56 Score_element *next_elt = i < elems.size ()
64 next_origin = next_elt->get_elt_property ("origin");
66 (next_origin == SCM_UNDEFINED)
71 next_origin = ly_str02scm ("begin-of-note");
74 = scm_eval (scm_listify (ly_symbol2scm ("break-align-spacer"),
75 current_origin, next_origin, SCM_UNDEFINED));
76 SCM symbol = gh_car (extra_space);
77 Real spc = gh_scm2double (SCM_CADR(extra_space));
81 symbol_list = gh_cons (symbol, symbol_list);
82 current_origin = next_origin;
86 // skip the first sym.
87 symbol_list = gh_cdr (scm_reverse (symbol_list));
88 for (int i=0; i <elems.size()-1; i++)
90 String sym_str = ly_symbol2string (gh_car (symbol_list));
91 elems[i]->set_elt_property (sym_str,
92 scm_cons (gh_double2scm (0),
93 gh_double2scm (dists[i+1])));
95 symbol_list = gh_cdr (symbol_list);
100 SCM first_pair = elems[0]->get_elt_property ("minimum-space");
101 if (gh_pair_p (first_pair))
102 first_pair = first_pair;
104 first_pair = gh_cons (gh_double2scm (0.0), gh_double2scm (0.0));
106 scm_set_car_x (first_pair, gh_double2scm (-dists[0]));
107 elems[0]->set_elt_property ("minimum-space", first_pair);
109 Axis_align_item::before_line_breaking ();
112 Real pre_space = elems[0]->relative_coordinate (column_l (), X_AXIS);
114 Real xl = elems[0]->extent (X_AXIS)[LEFT];
118 programming_error ("Infinity reached. ");
120 Real xr = elems.top ()->extent (X_AXIS)[RIGHT];
121 Real spring_len = elems.top ()->relative_coordinate (column_l (), X_AXIS);
125 programming_error ("Infinity reached.");
127 Real stretch_distance =0.;
129 if (gh_car (symbol_list) == ly_symbol2scm ("extra-space"))
131 spring_len += dists.top ();
132 stretch_distance = dists.top ();
134 else if (gh_car (symbol_list) == ly_symbol2scm ("minimum-space"))
136 spring_len = spring_len >? dists.top ();
137 stretch_distance = spring_len;
141 Hint the spacing engine how much space to put in.
144 The pairs are in the format of an interval (ie. CAR < CDR).
146 column_l ()->set_elt_property ("extra-space",
147 scm_cons (gh_double2scm (pre_space),
148 gh_double2scm (spring_len)));
150 column_l ()->set_elt_property ("stretch-distance",
151 gh_cons (gh_double2scm (-dists[0]),
152 gh_double2scm (stretch_distance)));
156 Break_align_item::Break_align_item ()
158 set_elt_property ("stacking-dir" , gh_int2scm (RIGHT));
161 add_offset_callback (Side_position_interface::aligned_on_self, X_AXIS);