lily/break-align-item.cc

   1 /*
   2   break-align-item.cc -- implement Break_align_item
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "dimension-cache.hh"
  10 #include "lily-guile.hh"
  11 #include "break-align-item.hh"
  12 #include "dimensions.hh"
  13 #include "paper-score.hh"
  14 #include "paper-def.hh"
  15 #include "paper-column.hh"
  16
  17 /*
  18   Handle spacing for prefatory matter.
  19
  20   TODO: rewrite this.  It is kludgy
  21 */
  22
  23 void
  24 Break_align_item::do_pre_processing()
  25 {
  26   if (break_status_dir() == LEFT)
  27     align_dir_ = LEFT;
  28   else
  29     align_dir_ = RIGHT;
  30
  31   flip (&align_dir_);
  32
  33   Real interline= paper_l ()->get_var ("interline");
  34
  35   Link_array<Score_element> elems;
  36   Link_array<Score_element> all_elems (elem_l_arr ());
  37
  38   for (int i=0; i < all_elems.size(); i++)
  39     {
  40       Interval y = all_elems[i]->extent(axis ());
  41       if (!y.empty_b())
  42         elems.push (dynamic_cast<Score_element*> (all_elems[i]));
  43     }
  44
  45   if (!elems.size ())
  46     return;
  47
  48   SCM symbol_list = SCM_EOL;
  49   Array<Real> dists;
  50   SCM current_origin = ly_str02scm ("");
  51   for (int i=0; i <= elems.size (); i++)
  52     {
  53       Score_element *next_elt  = i < elems.size ()
  54         ? elems[i]
  55         : 0 ;
  56
  57       SCM next_origin;
  58
  59       if (next_elt)
  60         {
  61           next_origin = next_elt->get_elt_property ("origin");
  62           next_origin =
  63             (next_origin == SCM_UNDEFINED)
  64             ? ly_str02scm ("")
  65             : next_origin;
  66         }
  67       else
  68         next_origin = ly_str02scm ("begin-of-note");
  69
  70       SCM extra_space
  71         = scm_eval (scm_listify (ly_symbol2scm ("break-align-spacer"),
  72                                  current_origin, next_origin, SCM_UNDEFINED));
  73       SCM symbol = gh_car  (extra_space);
  74       Real spc = gh_scm2double (SCM_CADR(extra_space));
  75       spc *= interline;
  76
  77       dists.push(spc);
  78       symbol_list = gh_cons (symbol, symbol_list);
  79       current_origin = next_origin;
  80     }
  81
  82
  83   // skip the first sym.
  84   symbol_list  = gh_cdr (scm_reverse (symbol_list));
  85   for (int i=0; i <elems.size()-1; i++)
  86     {
  87       String sym_str = ly_symbol2string (gh_car  (symbol_list));
  88       elems[i]->set_elt_property (sym_str,
  89                                   scm_cons (gh_double2scm (0),
  90                                             gh_double2scm (dists[i+1])));
  91
  92       symbol_list = gh_cdr (symbol_list);
  93     }
  94
  95
  96   // urg
  97   SCM first_pair = elems[0]->get_elt_property ("minimum-space");
  98   if (gh_pair_p (first_pair))
  99     first_pair = first_pair;
 100   else
 101     first_pair = gh_cons (gh_double2scm (0.0), gh_double2scm (0.0));
 102
 103   scm_set_car_x (first_pair, gh_double2scm (-dists[0]));
 104   elems[0]->set_elt_property ("minimum-space", first_pair);
 105
 106   Axis_align_item::do_pre_processing();
 107
 108
 109   Real pre_space = elems[0]->extent (X_AXIS)[LEFT]
 110     + elems[0]->relative_coordinate (column_l (), X_AXIS);
 111   Real spring_len = elems.top ()->extent (X_AXIS)[RIGHT]
 112     + elems.top ()->relative_coordinate (column_l (), X_AXIS);
 113
 114   Real stretch_distance =0.;
 115
 116   if (gh_car  (symbol_list) == ly_symbol2scm ("extra-space"))
 117     {
 118       spring_len += dists.top ();
 119       stretch_distance = dists.top ();
 120     }
 121   else if (gh_car  (symbol_list) == ly_symbol2scm ("minimum-space"))
 122     {
 123       spring_len = spring_len >? dists.top ();
 124       stretch_distance = spring_len;
 125     }
 126
 127   /*
 128     Hint the spacing engine how much space to put in.
 129
 130
 131     The pairs are in the format of an interval (ie. CAR <  CDR).
 132   */
 133   column_l ()->set_elt_property ("extra-space",
 134                                  scm_cons (gh_double2scm (pre_space),
 135                                            gh_double2scm (spring_len)));
 136
 137   column_l ()->set_elt_property ("stretch-distance",
 138                                  gh_cons (gh_double2scm (-dists[0]),
 139                                           gh_double2scm (stretch_distance)));
 140
 141 }
 142
 143 Break_align_item::Break_align_item ()
 144 {
 145   stacking_dir_ = RIGHT;
 146   set_axis (X_AXIS);
 147 }