lily/align-interface.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2000--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "align-interface.hh"
  21 #include "axis-group-interface.hh"
  22 #include "grob-array.hh"
  23 #include "hara-kiri-group-spanner.hh"
  24 #include "international.hh"
  25 #include "item.hh"
  26 #include "page-layout-problem.hh"
  27 #include "paper-book.hh"
  28 #include "paper-column.hh"
  29 #include "pointer-group-interface.hh"
  30 #include "spanner.hh"
  31 #include "skyline-pair.hh"
  32 #include "system.hh"
  33 #include "warn.hh"
  34
  35
  36 MAKE_SCHEME_CALLBACK (Align_interface, align_to_minimum_distances, 1);
  37 SCM
  38 Align_interface::align_to_minimum_distances (SCM smob)
  39 {
  40   Grob *me = unsmob_grob (smob);
  41
  42   me->set_property ("positioning-done", SCM_BOOL_T);
  43
  44   SCM axis = scm_car (me->get_property ("axes"));
  45   Axis ax = Axis (scm_to_int (axis));
  46
  47   Align_interface::align_elements_to_minimum_distances (me, ax);
  48
  49   return SCM_BOOL_T;
  50 }
  51
  52 MAKE_SCHEME_CALLBACK (Align_interface, align_to_ideal_distances, 1);
  53 SCM
  54 Align_interface::align_to_ideal_distances (SCM smob)
  55 {
  56   Grob *me = unsmob_grob (smob);
  57
  58   me->set_property ("positioning-done", SCM_BOOL_T);
  59
  60   Align_interface::align_elements_to_ideal_distances (me);
  61
  62   return SCM_BOOL_T;
  63 }
  64
  65 /* for each grob, find its upper and lower skylines. If the grob has
  66    an empty extent, delete it from the list instead. If the extent is
  67    non-empty but there is no skyline available (or pure is true), just
  68    create a flat skyline from the bounding box */
  69 // TODO(jneem): the pure and non-pure parts seem to share very little
  70 // code. Split them into 2 functions, perhaps?
  71 static void
  72 get_skylines (Grob *me,
  73               vector<Grob*> *const elements,
  74               Axis a,
  75               bool pure, int start, int end,
  76               vector<Skyline_pair> *const ret)
  77 {
  78   Grob *other_common = common_refpoint_of_array (*elements, me, other_axis (a));
  79
  80   for (vsize i = elements->size (); i--;)
  81     {
  82       Grob *g = (*elements)[i];
  83       Skyline_pair skylines;
  84
  85       if (!pure)
  86         {
  87           Skyline_pair *skys = Skyline_pair::unsmob (g->get_property (a == Y_AXIS
  88                                                                       ? "vertical-skylines"
  89                                                                       : "horizontal-skylines"));
  90           if (skys)
  91             skylines = *skys;
  92
  93           /* This skyline was calculated relative to the grob g. In order to compare it to
  94              skylines belonging to other grobs, we need to shift it so that it is relative
  95              to the common reference. */
  96           Real offset = g->relative_coordinate (other_common, other_axis (a));
  97           skylines.shift (offset);
  98         }
  99       else
 100         {
 101           assert (a == Y_AXIS);
 102           Interval extent = g->pure_height (g, start, end);
 103
 104           // This is a hack to get better accuracy on the pure-height of VerticalAlignment.
 105           // It's quite common for a treble clef to be the highest element of one system
 106           // and for a low note (or lyrics) to be the lowest note on another. The two will
 107           // never collide, but the pure-height stuff only works with bounding boxes, so it
 108           // doesn't know that. The result is a significant over-estimation of the pure-height,
 109           // especially on systems with many staves. To correct for this, we build a skyline
 110           // in two parts: the part we did above contains most of the grobs (note-heads, etc.)
 111           // while the bit we're about to do only contains the breakable grobs at the beginning
 112           // of the system. This way, the tall treble clefs are only compared with the treble
 113           // clefs of the other staff and they will be ignored if the staff above is, for example,
 114           // lyrics.
 115           if (Axis_group_interface::has_interface (g)
 116               && !Hara_kiri_group_spanner::request_suicide (g, start, end))
 117             {
 118               extent = Axis_group_interface::rest_of_line_pure_height (g, start, end);
 119               Interval begin_of_line_extent = Axis_group_interface::begin_of_line_pure_height (g, start);
 120               if (!begin_of_line_extent.is_empty ())
 121                 {
 122                   Box b;
 123                   b[a] = begin_of_line_extent;
 124                   b[other_axis (a)] = Interval (-infinity_f, -1);
 125                   skylines.insert (b, 0, other_axis (a));
 126                 }
 127             }
 128
 129           if (!extent.is_empty ())
 130             {
 131               Box b;
 132               b[a] = extent;
 133               b[other_axis (a)] = Interval (0, infinity_f);
 134               skylines.insert (b, 0, other_axis (a));
 135             }
 136         }
 137
 138       if (skylines.is_empty ())
 139         elements->erase (elements->begin () + i);
 140       else
 141         ret->push_back (skylines);
 142     }
 143   reverse (*ret);
 144 }
 145
 146 vector<Real>
 147 Align_interface::get_minimum_translations (Grob *me,
 148                                            vector<Grob*> const &all_grobs,
 149                                            Axis a,
 150                                            bool pure, int start, int end)
 151 {
 152   if (!pure && a == Y_AXIS && dynamic_cast<Spanner*> (me) && !me->get_system ())
 153     me->programming_error ("vertical alignment called before line-breaking");
 154
 155   Direction stacking_dir = robust_scm2dir (me->get_property ("stacking-dir"),
 156                                            DOWN);
 157   vector<Grob*> elems (all_grobs); // writable copy
 158   vector<Skyline_pair> skylines;
 159
 160   get_skylines (me, &elems, a, pure, start, end, &skylines);
 161
 162   Real where = 0;
 163   Real default_padding = robust_scm2double (me->get_property ("padding"), 0.0);
 164   vector<Real> translates;
 165   Skyline down_skyline (stacking_dir);
 166   Real last_spaceable_element_pos = 0;
 167   Grob *last_spaceable_element = 0;
 168   for (vsize j = 0; j < elems.size (); j++)
 169     {
 170       Real dy = 0;
 171       Real padding = default_padding;
 172
 173       if (j == 0)
 174         dy = skylines[j][-stacking_dir].max_height ();
 175       else
 176         {
 177           down_skyline.merge (skylines[j-1][stacking_dir]);
 178           dy = down_skyline.distance (skylines[j][-stacking_dir]);
 179
 180           SCM spec = Page_layout_problem::get_spacing_spec (elems[j-1], elems[j], pure, start, end);
 181           Page_layout_problem::read_spacing_spec (spec, &padding, ly_symbol2scm ("padding"));
 182
 183           Real min_distance = 0;
 184           if (Page_layout_problem::read_spacing_spec (spec, &min_distance, ly_symbol2scm ("minimum-distance")))
 185             dy = max (dy, min_distance);
 186
 187           if (Page_layout_problem::is_spaceable (elems[j]) && last_spaceable_element)
 188             {
 189               // Spaceable staves may have min-distance and padding
 190               // constraints coming from the previous spaceable staff
 191               // as well as from the previous staff.
 192               spec = Page_layout_problem::get_spacing_spec (last_spaceable_element, elems[j], pure, start, end);
 193               Real spaceable_padding = 0;
 194               Page_layout_problem::read_spacing_spec (spec,
 195                                                       &spaceable_padding,
 196                                                       ly_symbol2scm ("padding"));
 197               padding = max (padding, spaceable_padding);
 198
 199               Real min_distance = 0;
 200               if (Page_layout_problem::read_spacing_spec (spec,
 201                                                           &min_distance,
 202                                                           ly_symbol2scm ("minimum-distance")))
 203                 dy = max (dy, min_distance + stacking_dir*(last_spaceable_element_pos - where));
 204             }
 205         }
 206
 207       if (isinf (dy)) /* if the skyline is empty, maybe max_height is infinity_f */
 208         dy = 0.0;
 209
 210       dy = max (0.0, dy + padding);
 211       down_skyline.raise (-stacking_dir * dy);
 212       where += stacking_dir * dy;
 213       translates.push_back (where);
 214
 215       if (Page_layout_problem::is_spaceable (elems[j]))
 216         {
 217           last_spaceable_element = elems[j];
 218           last_spaceable_element_pos = where;
 219         }
 220     }
 221
 222   // So far, we've computed the translates for all the non-empty elements.
 223   // Here, we set the translates for the empty elements: an empty element
 224   // gets the same translation as the last non-empty element before it.
 225   vector<Real> all_translates;
 226   if (!translates.empty ())
 227     {
 228       Real w = translates[0];
 229       for  (vsize i = 0, j = 0; j < all_grobs.size (); j++)
 230         {
 231           if (i < elems.size () && all_grobs[j] == elems[i])
 232             w = translates[i++];
 233           all_translates.push_back (w);
 234         }
 235     }
 236   return all_translates;
 237 }
 238
 239 void
 240 Align_interface::align_elements_to_ideal_distances (Grob *me)
 241 {
 242   System *sys = me->get_system ();
 243   if (sys)
 244     {
 245       Page_layout_problem layout (NULL, SCM_EOL, scm_list_1 (sys->self_scm ()));
 246       layout.solution (true);
 247     }
 248   else
 249     programming_error ("vertical alignment called before line breaking");
 250 }
 251
 252 void
 253 Align_interface::align_elements_to_minimum_distances (Grob *me, Axis a)
 254 {
 255   extract_grob_set (me, "elements", all_grobs);
 256
 257   vector<Real> translates = get_minimum_translations (me, all_grobs, a, false, 0, 0);
 258   if (translates.size ())
 259     for (vsize j = 0; j < all_grobs.size (); j++)
 260       all_grobs[j]->translate_axis (translates[j], a);
 261 }
 262
 263 Real
 264 Align_interface::get_pure_child_y_translation (Grob *me, Grob *ch, int start, int end)
 265 {
 266   extract_grob_set (me, "elements", all_grobs);
 267   vector<Real> translates = get_minimum_translations (me, all_grobs, Y_AXIS, true, start, end);
 268
 269   if (translates.size ())
 270     {
 271       for (vsize i = 0; i < all_grobs.size (); i++)
 272         if (all_grobs[i] == ch)
 273           return translates[i];
 274     }
 275   else
 276     return 0;
 277
 278   programming_error ("tried to get a translation for something that is no child of mine");
 279   return 0;
 280 }
 281
 282 Axis
 283 Align_interface::axis (Grob *me)
 284 {
 285   return Axis (scm_to_int (scm_car (me->get_property ("axes"))));
 286 }
 287
 288 void
 289 Align_interface::add_element (Grob *me, Grob *element)
 290 {
 291   Axis a = Align_interface::axis (me);
 292   SCM sym = axis_offset_symbol (a);
 293   SCM proc = axis_parent_positioning (a);
 294
 295   element->set_property (sym, proc);
 296   Axis_group_interface::add_element (me, element);
 297 }
 298
 299 void
 300 Align_interface::set_ordered (Grob *me)
 301 {
 302   SCM ga_scm = me->get_object ("elements");
 303   Grob_array *ga = unsmob_grob_array (ga_scm);
 304   if (!ga)
 305     {
 306       ga_scm = Grob_array::make_array ();
 307       ga = unsmob_grob_array (ga_scm);
 308       me->set_object ("elements", ga_scm);
 309     }
 310
 311   ga->set_ordered (true);
 312 }
 313
 314 ADD_INTERFACE (Align_interface,
 315                "Order grobs from top to bottom, left to right, right to left"
 316                " or bottom to top.  For vertical alignments of staves, the"
 317                " @code{break-system-details} of the left"
 318                " @rinternals{NonMusicalPaperColumn} may be set to tune"
 319                " vertical spacing.",
 320
 321                /* properties */
 322                "align-dir "
 323                "axes "
 324                "elements "
 325                "padding "
 326                "positioning-done "
 327                "stacking-dir "
 328                );