lily/paper-column.cc

   1 /*
   2   paper-column.cc -- implement Paper_column
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "moment.hh"
  10 #include "paper-column.hh"
  11 #include "paper-score.hh"
  12 #include "warn.hh"
  13 #include "axis-group-interface.hh"
  14 #include "spaceable-grob.hh"
  15 #include "molecule.hh"
  16 #include "text-item.hh"
  17 #include "lookup.hh"
  18 #include "font-interface.hh"
  19
  20
  21
  22
  23
  24 ADD_INTERFACE (Paper_column, "paper-column-interface",
  25   "  Paper_columns form the top-most item parent. (The Paper_columns X\n"
  26 "  parent is System, which is a spanner.)\n"
  27 "\n"
  28 "  Paper_columns form the units for the spacing engine. They are\n"
  29 "  numbered, the first (leftmost) is column 0. Numbering happens before\n"
  30 "  line-breaking, and columns are not renumbered after line breaking.\n"
  31 "\n"
  32 "  Since many columns go unused, you should only use the rank field to\n"
  33 "  get ordering information.  Two adjacent columns may have\n"
  34 "  non-adjacent numbers.\n"
  35 "\n"
  36 "  Don't be confused by right-items: each spacing wish can also contain\n"
  37 "  a number of items, with which a spacing constraint may be kept. It's\n"
  38 "  a little baroque, but it might come in handy later on?\n"
  39 "\n",
  40   "between-cols between-system-string when bounded-by-me shortest-playing-duration shortest-starter-duration");
  41
  42
  43 void
  44 Paper_column::do_break_processing ()
  45 {
  46   Spaceable_grob::remove_interface (this);
  47   Item::do_break_processing ();
  48 }
  49
  50
  51 int
  52 Paper_column::get_rank (Grob*me)
  53 {
  54   return dynamic_cast<Paper_column*> (me)->rank_;
  55 }
  56
  57 System*
  58 Paper_column::get_system () const
  59 {
  60   return system_;
  61 }
  62
  63 Paper_column*
  64 Paper_column::get_column () const
  65 {
  66   return (Paper_column*) (this);
  67 }
  68
  69 Paper_column::Paper_column (SCM l)
  70   : Item (l)            // guh.?
  71 {
  72   system_=0;
  73   rank_ = -1;
  74 }
  75
  76 Moment
  77 Paper_column::when_mom (Grob*me)
  78 {
  79   SCM m = me->get_grob_property ("when");
  80   Moment s (0);
  81   if (unsmob_moment (m))
  82     {
  83       return *unsmob_moment (m);
  84     }
  85   return s;
  86 }
  87
  88 bool
  89 Paper_column::musical_b (Grob *me)
  90 {
  91   SCM m = me->get_grob_property ("shortest-starter-duration");
  92   Moment s (0);
  93   if (unsmob_moment (m))
  94     {
  95       s = *unsmob_moment (m);
  96     }
  97   return s != Moment (0);
  98
  99 }
 100
 101
 102 bool
 103 Paper_column::used_b (Grob*me)
 104 {
 105   return gh_pair_p (me->get_grob_property ("elements")) ||  Item::breakable_b (me)
 106     || gh_pair_p (me->get_grob_property ("bounded-by-me"))
 107     ;
 108 }
 109
 110 /*
 111   Print a vertical line and  the rank number, to aid debugging.
 112  */
 113
 114 MAKE_SCHEME_CALLBACK(Paper_column,brew_molecule,1);
 115 SCM
 116 Paper_column::brew_molecule (SCM p)
 117 {
 118   Grob *me = unsmob_grob (p);
 119
 120   String r = to_string (Paper_column::get_rank (me));
 121   SCM properties = Font_interface::font_alist_chain (me);
 122
 123   Molecule t = Text_item::text2molecule (me, scm_makfrom0str (r.to_str0 ()),
 124                                          properties);
 125   t.align_to (X_AXIS, CENTER);
 126   t.align_to (Y_AXIS, DOWN);
 127
 128   Molecule l = Lookup::filledbox (Box (Interval (-0.01, 0.01),
 129                                        Interval (-2, -1)));
 130
 131   t.add_molecule (l);
 132   return t.smobbed_copy ();
 133 }
 134
 135 /*
 136   This is all too hairy. We use bounded-by-me to make sure that some
 137   columns are kept "alive". Unfortunately, when spanners are suicided,
 138   this falls apart again. (sigh.)
 139
 140   THIS IS BROKEN KLUDGE. WE SHOULD INVENT SOMETHING BETTER.
 141  */
 142 MAKE_SCHEME_CALLBACK(Paper_column,before_line_breaking,1);
 143 SCM
 144 Paper_column::before_line_breaking (SCM grob)
 145 {
 146   Grob *me = unsmob_grob (grob);
 147
 148   SCM c = me->get_grob_property ("bounded-by-me");
 149   SCM *ptrptr = &c;
 150
 151   while (gh_pair_p (*ptrptr))
 152     {
 153       Grob * g = unsmob_grob (gh_car (*ptrptr));
 154
 155       if (!g || !g->live ())
 156         {
 157           *ptrptr = gh_cdr (*ptrptr);
 158         }
 159       else
 160         {
 161           ptrptr = SCM_CDRLOC (*ptrptr);
 162         }
 163     }
 164
 165   me->set_grob_property ("bounded-by-me", c);
 166   return SCM_UNSPECIFIED;
 167 }