lily/hyphen-spanner.cc

   1 /*
   2   hyphen-spanner.cc -- implement Hyphen_spanner
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1999--2003 Glen Prideaux <glenprideaux@iname.com>
   7
   8  (adapted from lyric-extender)
   9 */
  10
  11 #include <math.h>
  12
  13 #include "box.hh"
  14 #include "lookup.hh"
  15 #include "molecule.hh"
  16 #include "paper-def.hh"
  17 #include "hyphen-spanner.hh"
  18 #include "paper-column.hh"
  19 #include "spanner.hh"
  20 #include "item.hh"
  21
  22 MAKE_SCHEME_CALLBACK (Hyphen_spanner,set_spacing_rods,1);
  23 SCM
  24 Hyphen_spanner::set_spacing_rods (SCM smob)
  25 {
  26   Grob*me = unsmob_grob (smob);
  27
  28   Rod rod;
  29   Spanner*sp = dynamic_cast<Spanner*> (me);
  30   Item * l = sp->get_bound (LEFT);
  31   Item * r =  sp->get_bound (RIGHT);
  32   rod.item_l_drul_[LEFT] = l;
  33   rod.item_l_drul_[RIGHT] =r;
  34   rod.distance_ =
  35     gh_scm2double (me->get_grob_property ("minimum-length"))
  36     + l->extent (l, X_AXIS)[RIGHT]
  37     - r->extent (r, X_AXIS)[LEFT];
  38
  39   rod.add_to_cols ();
  40   return SCM_UNSPECIFIED;
  41 }
  42
  43 MAKE_SCHEME_CALLBACK (Hyphen_spanner,brew_molecule,1)
  44 SCM
  45 Hyphen_spanner::brew_molecule (SCM smob)
  46 {
  47   Spanner * sp = unsmob_spanner (smob);
  48
  49   Grob * common = sp;
  50   Direction d = LEFT;
  51   do
  52     {
  53       common = common->common_refpoint (sp->get_bound (d), X_AXIS);
  54     }
  55   while (flip (&d) != LEFT);
  56   Interval bounds;
  57
  58   do
  59     {
  60       Interval iv = sp->get_bound (d)->extent (common, X_AXIS);
  61
  62       bounds[d] = iv.empty_b ()
  63         ? sp->get_bound (d)->relative_coordinate (common, X_AXIS)
  64         : iv[-d];
  65     }
  66   while (flip (&d) != LEFT);
  67
  68   Real lt = sp->get_paper ()->get_realvar (ly_symbol2scm ("linethickness"));
  69   Real th = gh_scm2double (sp->get_grob_property ("thickness")) * lt ;
  70   Real h = gh_scm2double (sp->get_grob_property ("height"));
  71
  72   // interval?
  73   Real x = gh_scm2double (sp->get_grob_property ("maximum-length"));
  74   SCM space =  sp->get_bound (LEFT)->get_grob_property ("word-space");
  75
  76   Real word_space  = 1.0;
  77   if (gh_number_p (space))
  78     {
  79       word_space = gh_scm2double (space);
  80     }
  81
  82   /*
  83     We remove word space from the distance so it doesn't look like an extender.
  84
  85    */
  86   Real l = (gh_scm2double (sp->get_grob_property ("minimum-length"))
  87     - word_space ) >? word_space;
  88
  89
  90   /*
  91     we should probably do something more intelligent when bounds is
  92     empty, but at least this doesn't crash.
  93   */
  94   Real w  = bounds.empty_b () ? 0 : bounds.length ();
  95
  96   /* for length, use a geometric mean of the available space and some minimum
  97    */
  98   if (l < w)
  99     {
 100       l = sqrt (l*w);
 101       if (l > x)
 102         l = x;
 103     }
 104   else
 105     {
 106       /* OK, we have a problem. Usually this means that we're on the
 107          first column, and we have a long lyric which extends to near
 108          the offset for stuff */
 109       /* This test for being on the first column has been shamelessly
 110          ripped from spanner.cc */
 111       Paper_column *sc = dynamic_cast<Paper_column*> (sp->get_bound (LEFT)->get_column ());
 112       if (sc != NULL &&
 113           sc->break_status_dir () == RIGHT)
 114         {
 115           /* We are on the first column, so it's probably harmless to
 116              get the minimum length back by extending leftwards into
 117              the space under the clef/key sig/time sig */
 118           bounds[LEFT] = bounds[RIGHT] - l;
 119         }
 120       else
 121         {
 122           /* We can't get the length desired. Maybe we should warn. */
 123           l = w;
 124         }
 125     }
 126   Box b (Interval (-l/2,l/2), Interval (h,h+th));
 127   Molecule mol (Lookup::filledbox (b));
 128   Real ct = bounds.empty_b () ? 0 : bounds.center () ;
 129   mol.translate_axis (ct -sp->relative_coordinate (common, X_AXIS), X_AXIS);
 130   return mol.smobbed_copy ();
 131 }
 132
 133 void
 134 Hyphen_spanner::set_textitem (Direction d, Grob* b)
 135 {
 136   elt_->set_bound (d, b);
 137   elt_->add_dependency (b);
 138 }
 139
 140 Hyphen_spanner::Hyphen_spanner (Spanner*s)
 141 {
 142   elt_ = s;
 143 }
 144
 145
 146
 147 ADD_INTERFACE (Hyphen_spanner, "lyric-hyphen-interface",
 148   "A centred hyphen is a simple line between lyrics used to divide "
 149 "syllables.   The length of the hyphen line should stretch based on the "
 150 "size of the gap between syllables.",
 151   "thickness height minimum-length maximum-length word-space");
 152