lily/break-align-interface.cc

   1 /*
   2   break-align-interface.cc -- implement Break_align_interface
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9
  10 #include <math.h>
  11 #include <libc-extension.hh>    // isinf
  12
  13 #include "self-alignment-interface.hh"
  14 #include "side-position-interface.hh"
  15 #include "axis-group-interface.hh"
  16 #include "warn.hh"
  17 #include "lily-guile.hh"
  18 #include "break-align-interface.hh"
  19 #include "dimensions.hh"
  20 #include "output-def.hh"
  21 #include "paper-column.hh"
  22 #include "group-interface.hh"
  23 #include "align-interface.hh"
  24
  25 MAKE_SCHEME_CALLBACK (Break_align_interface,alignment_callback,2);
  26
  27 SCM
  28 Break_align_interface::alignment_callback (SCM element_smob, SCM axis)
  29 {
  30   Grob *me = unsmob_grob (element_smob);
  31   Axis a = (Axis) ly_scm2int (axis);
  32
  33   assert (a == X_AXIS);
  34   Grob *par = me->get_parent (a);
  35   if (par && !to_boolean (par->get_property ("positioning-done")))
  36     {
  37       par->set_property ("positioning-done", SCM_BOOL_T);
  38       Break_align_interface::do_alignment (par);
  39     }
  40
  41   return scm_make_real (0);
  42 }
  43
  44 MAKE_SCHEME_CALLBACK (Break_align_interface,self_align_callback,2);
  45 SCM
  46 Break_align_interface::self_align_callback (SCM element_smob, SCM axis)
  47 {
  48   Grob *me = unsmob_grob (element_smob);
  49   Axis a = (Axis) ly_scm2int (axis);
  50   assert (a == X_AXIS);
  51
  52   Item* item = dynamic_cast<Item*> (me);
  53   Direction bsd = item->break_status_dir ();
  54   if (bsd == LEFT)
  55     {
  56       me->set_property ("self-alignment-X", scm_int2num (RIGHT));
  57     }
  58
  59   /*
  60     Force break alignment itself to be done first, in the case
  61    */
  62   return Self_alignment_interface::aligned_on_self (element_smob, axis);
  63 }
  64
  65
  66 /*
  67   This is tricky: we cannot modify 'elements, since callers are
  68   iterating the same list. Reordering the list in-place, or resetting
  69   'elements will skip elements in the loops of callers.
  70
  71   So we return the correct order as an array.
  72  */
  73 Link_array<Grob>
  74 Break_align_interface::ordered_elements (Grob *grob)
  75 {
  76   Item *me  = dynamic_cast<Item*> (grob);
  77   SCM elts = me->get_property ("elements");
  78   SCM order_vec = me->get_property ("break-align-orders");
  79   if (!ly_c_vector_p (order_vec)
  80       || ly_vector_length (order_vec) < 3)
  81     return  Pointer_group_interface__extract_grobs (me, (Grob*)0,
  82                                                     "elements");
  83   SCM order = scm_vector_ref (order_vec,
  84                               scm_int2num (me->break_status_dir() + 1));
  85
  86
  87   /*
  88     Copy in order specified in BREAK-ALIGN-ORDER.
  89   */
  90   Link_array<Grob> new_elts;
  91   for (; ly_c_pair_p (order); order = ly_cdr (order))
  92     {
  93       SCM sym = ly_car (order);
  94
  95       for (SCM s =elts; ly_c_pair_p (s); s = ly_cdr (s))
  96         {
  97           Grob *g = unsmob_grob (ly_car (s));
  98           if (g && sym == g->get_property ("break-align-symbol"))
  99             {
 100               new_elts.push (g);
 101               elts = scm_delq (g->self_scm (), elts);
 102             }
 103         }
 104     }
 105   return new_elts;
 106 }
 107
 108 void
 109 Break_align_interface::add_element (Grob*me, Grob *toadd)
 110 {
 111   Axis_group_interface::add_element (me, toadd);
 112 }
 113
 114 void
 115 Break_align_interface::do_alignment (Grob *grob)
 116 {
 117   Item * me = dynamic_cast<Item*> (grob);
 118
 119
 120   Link_array<Grob> elems = ordered_elements (me);
 121   Array<Interval> extents;
 122
 123   int last_nonempty = -1;
 124   for (int i=0; i < elems.size (); i++)
 125     {
 126       Interval y = elems[i]->extent (elems[i], X_AXIS);
 127       extents.push (y);
 128       if (!y.is_empty ())
 129         last_nonempty = i;
 130     }
 131
 132   int idx  = 0;
 133   while (idx < extents.size  () && extents[idx].is_empty ())
 134     idx++;
 135
 136   Array<Real> offsets;
 137   offsets.set_size (elems.size ());
 138   for (int i= 0; i < offsets.size ();i ++)
 139     offsets[i] = 0.0;
 140
 141
 142   Real extra_right_space = 0.0;
 143   int edge_idx = -1;
 144   while (idx < elems.size ())
 145     {
 146       int next_idx = idx+1;
 147       while (next_idx < elems.size () &&
 148              extents[next_idx].is_empty () )
 149         next_idx++;
 150
 151       Grob *l = elems[idx];
 152       Grob *r = 0;
 153
 154       if (next_idx < elems.size ())
 155         r = elems[next_idx];
 156
 157       SCM alist = SCM_EOL;
 158
 159
 160       /*
 161         Find the first grob with a space-alist entry.
 162        */
 163       for (SCM s = l->get_property ("elements");
 164            ly_c_pair_p (s) ; s = ly_cdr (s))
 165           {
 166             Grob *elt = unsmob_grob (ly_car (s));
 167
 168             if (edge_idx < 0
 169                 && elt->get_property ("break-align-symbol")
 170                 == ly_symbol2scm ( "left-edge"))
 171               edge_idx = idx;
 172
 173             SCM l =elt->get_property ("space-alist");
 174             if (ly_c_pair_p (l))
 175               {
 176                 alist= l;
 177                 break;
 178               }
 179           }
 180
 181       SCM rsym = r ? SCM_EOL : ly_symbol2scm ("right-edge");
 182
 183       /*
 184         We used to use #'cause to find out the symbol and the spacing
 185         table, but that gets icky when that grob is suicided for some
 186         reason.
 187       */
 188       for (SCM s = r ? r->get_property ("elements") : SCM_EOL;
 189            !ly_c_symbol_p (rsym) && ly_c_pair_p (s); s = ly_cdr (s))
 190         {
 191           Grob * elt =unsmob_grob (ly_car (s));
 192
 193           rsym = elt->get_property ("break-align-symbol");
 194         }
 195
 196       if (rsym  == ly_symbol2scm ("left-edge"))
 197         edge_idx = next_idx;
 198
 199       SCM entry = SCM_EOL;
 200       if (ly_c_symbol_p (rsym))
 201         entry = scm_assq (rsym, alist);
 202
 203       bool entry_found = ly_c_pair_p (entry);
 204       if (!entry_found)
 205         {
 206           String sym_string;
 207           if (ly_c_symbol_p (rsym))
 208             sym_string = ly_symbol2string (rsym);
 209
 210           String orig_string ;
 211           if (unsmob_grob (l->get_property ("cause")))
 212             orig_string = unsmob_grob (l->get_property ("cause"))->name ();
 213
 214           programming_error (_f ("No spacing entry from %s to `%s'",
 215                                 orig_string.to_str0 (),
 216                                 sym_string.to_str0 ()));
 217         }
 218
 219       Real distance = 1.0;
 220       SCM type = ly_symbol2scm ("extra-space");
 221
 222       if (entry_found)
 223         {
 224           entry = ly_cdr (entry);
 225
 226           distance = ly_scm2double (ly_cdr (entry));
 227           type = ly_car (entry) ;
 228         }
 229
 230       if (r)
 231         {
 232           if (type == ly_symbol2scm ("extra-space"))
 233             offsets[next_idx] = extents[idx][RIGHT] + distance
 234               - extents[next_idx][LEFT];
 235           /* should probably junk minimum-space */
 236           else if (type == ly_symbol2scm ("minimum-space"))
 237             offsets[next_idx] = extents[idx][RIGHT] >? distance;
 238         }
 239       else
 240         {
 241           extra_right_space = distance;
 242         }
 243
 244       idx = next_idx;
 245     }
 246
 247   Real here = 0.0;
 248   Interval total_extent;
 249
 250   Real alignment_off =0.0;
 251   for (int i =0 ; i < offsets.size (); i++)
 252     {
 253       here += offsets[i];
 254       if (i == edge_idx)
 255         alignment_off = -here;
 256       total_extent.unite (extents[i] + here);
 257     }
 258
 259
 260   if (me->break_status_dir () == LEFT)
 261     {
 262       alignment_off = - total_extent[RIGHT] - extra_right_space;
 263     }
 264   else if (edge_idx < 0)
 265     alignment_off = -total_extent[LEFT];
 266
 267   here = alignment_off;
 268   for (int i =0 ; i < offsets.size (); i++)
 269     {
 270       here += offsets[i];
 271       elems[i]->translate_axis (here, X_AXIS);
 272     }
 273 }
 274
 275
 276 ADD_INTERFACE (Break_aligned_interface, "break-aligned-interface",
 277                "Items that are aligned in prefatory matter.\n"
 278                "\n"
 279                "The spacing of these items is controlled by the @code{space-alist}\n"
 280                "property. It contains a list @code{break-align-symbol}s with a specification\n"
 281                "of the associated space. The space specification can be "
 282                "@table @code\n"
 283                "@item (minimum-space . @var{spc}))\n"
 284                "  Pad space until the distance is @var{spc}\n"
 285                "@item (fixed-space . @var{spc})\n"
 286                "  Set a fixed space\n"
 287                "@item (semi-fixed-space . @var{spc})\n"
 288                "  Set a space. Half of it is fixed and half is stretchable. \n"
 289                "(does not work at start of line. fixme)\n"
 290                "@item (extra-space . @var{spc})\n"
 291                "  Add @var{spc} amount of space.\n"
 292                "@end table\n"
 293                "\n"
 294                "Special keys for the alist are @code{first-note} and @code{next-note}, signifying\n"
 295                "the first note on a line, and the next note halfway a line.\n"
 296                "\n"
 297                "Rules for this spacing are much more complicated than this. \n"
 298                "See [Wanske] page 126 -- 134, [Ross] pg 143 -- 147\n",
 299                "break-align-symbol space-alist");
 300
 301 ADD_INTERFACE (Break_align_interface, "break-alignment-interface",
 302                "The object that performs break aligment. See @ref{break-aligned-interface}.",
 303                "positioning-done break-align-orders");
 304
 305
 306