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 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,brew_molecule,1)
  23
  24 SCM
  25 Hyphen_spanner::brew_molecule (SCM smob)
  26 {
  27   Spanner * sp = unsmob_spanner (smob);
  28
  29   Grob * common = sp;
  30   Direction d = LEFT;
  31   do
  32     {
  33       common = common->common_refpoint (sp->get_bound (d), X_AXIS);
  34     }
  35   while (flip (&d) != LEFT);
  36   Interval bounds;
  37
  38   do
  39     {
  40       Interval iv = sp->get_bound (d)->extent (common, X_AXIS);
  41
  42       bounds[d] = iv.empty_b ()
  43         ? sp->get_bound (d)->relative_coordinate (common, X_AXIS)
  44         : iv[-d];
  45     }
  46   while (flip (&d) != LEFT);
  47
  48   Real lt = sp->get_paper ()->get_var ("linethickness");
  49   Real th = gh_scm2double (sp->get_grob_property ("thickness")) * lt ;
  50   Real h = gh_scm2double (sp->get_grob_property ("height"));
  51
  52   // interval?
  53   Real l = gh_scm2double (sp->get_grob_property ("minimum-length"));
  54   Real x = gh_scm2double (sp->get_grob_property ("maximum-length"));
  55   // The hyphen can exist in the word space of the left lyric ...
  56   SCM space =  sp->get_bound (LEFT)->get_grob_property ("word-space");
  57   if (gh_number_p (space))
  58     {
  59       bounds[LEFT] -=  gh_scm2double (space);
  60     }
  61
  62   /*
  63     we should probably do something more intelligent when bounds is
  64     empty, but at least this doesn't crash.
  65   */
  66   Real w  = bounds.empty_b () ? 0 : bounds.length ();
  67
  68   /* for length, use a geometric mean of the available space and some minimum
  69    */
  70   if (l < w)
  71     {
  72       l = sqrt (l*w);
  73       if (l > x)
  74         l = x;
  75     }
  76   else
  77     {
  78       /* OK, we have a problem. Usually this means that we're on the
  79          first column, and we have a long lyric which extends to near
  80          the offset for stuff */
  81       /* This test for being on the first column has been shamelessly
  82          ripped from spanner.cc */
  83       Paper_column *sc = dynamic_cast<Paper_column*> (sp->get_bound (LEFT)->get_column ());
  84       if (sc != NULL &&
  85           sc->break_status_dir () == RIGHT)
  86         {
  87           /* We are on the first column, so it's probably harmless to
  88              get the minimum length back by extending leftwards into
  89              the space under the clef/key sig/time sig */
  90           bounds[LEFT] = bounds[RIGHT] - l;
  91         }
  92       else
  93         {
  94           /* We can't get the length desired. Maybe we should warn. */
  95           l = w;
  96         }
  97     }
  98   Box b (Interval (-l/2,l/2), Interval (h,h+th));
  99   Molecule mol (Lookup::filledbox (b));
 100   Real ct = bounds.empty_b () ? 0 : bounds.center () ;
 101   mol.translate_axis (ct -sp->relative_coordinate (common, X_AXIS), X_AXIS);
 102   return mol.smobbed_copy ();
 103 }
 104
 105 void
 106 Hyphen_spanner::set_textitem (Direction d, Grob* b)
 107 {
 108   elt_->set_bound (d, b);
 109   elt_->add_dependency (b);
 110 }
 111
 112 Hyphen_spanner::Hyphen_spanner (Spanner*s)
 113 {
 114   elt_ = s;
 115 }
 116
 117
 118
 119 ADD_INTERFACE (Hyphen_spanner, "lyric-hyphen-interface",
 120   "A centred hyphen is a simple line between lyrics used to divide
 121 syllables.   The length of the hyphen line should stretch based on the
 122 size of the gap between syllables.",
 123   "thickness height minimum-length maximum-length word-space");
 124