lily/time-signature.cc

   1 /*
   2   time-signature.cc --  implement Time_signature
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10
  11 #include "molecule.hh"
  12 #include "text-item.hh"
  13 #include "time-signature.hh"
  14 #include "paper-def.hh"
  15 #include "font-interface.hh"
  16
  17 MAKE_SCHEME_CALLBACK (Time_signature,brew_molecule,1);
  18 /*
  19   TODO: make different functions for special and normal timesigs.
  20  */
  21 SCM
  22 Time_signature::brew_molecule (SCM smob)
  23 {
  24   Grob * me = unsmob_grob (smob);
  25   SCM st = me->get_grob_property ("style");
  26   SCM frac = me->get_grob_property ("fraction");
  27   int n = 4;
  28   int d = 4;
  29   if (gh_pair_p (frac))
  30     {
  31       n = gh_scm2int (gh_car (frac));
  32       d = gh_scm2int (gh_cdr (frac));
  33     }
  34
  35
  36   if (gh_symbol_p (st))
  37     {
  38       String style (ly_scm2string (scm_symbol_to_string (st)));
  39       if (style[0]=='1')
  40         {
  41           return time_signature (me, n, 0).smobbed_copy ();
  42         }
  43       else
  44         {
  45           return special_time_signature (me, style, n, d).smobbed_copy ();
  46         }
  47     }
  48   else
  49     return time_signature (me, n,d).smobbed_copy ();
  50 }
  51
  52 Molecule
  53 Time_signature::special_time_signature (Grob*me, String s, int n, int d)
  54 {
  55   /*
  56     Randomly probing the font sucks?
  57   */
  58
  59   SCM alist_chain = Font_interface::font_alist_chain (me);
  60
  61   SCM style_chain =
  62     Font_interface::add_style (me, ly_symbol2scm ("timesig-symbol"),
  63                                alist_chain);
  64
  65   Font_metric *feta = Font_interface::get_font (me, style_chain);
  66
  67   /*
  68     First guess: s contains only the signature style, append fraction.
  69   */
  70   String symbolname = "timesig-" + s + to_str (n) + "/" + to_str (d);
  71
  72   Molecule m = feta->find_by_name (symbolname);
  73   if (!m.empty_b ())
  74     return m;
  75
  76   /*
  77     Second guess: s contains the full signature name
  78   */
  79   m = feta->find_by_name ("timesig-" + s);
  80   if (!m.empty_b ())
  81     return m;
  82
  83   // Resort to default layout with numbers
  84   return time_signature (me, n, d);
  85 }
  86
  87
  88 Molecule
  89 Time_signature::time_signature (Grob*me,int num, int den)
  90 {
  91   SCM chain = Font_interface::font_alist_chain (me);
  92
  93   Molecule n = Text_item::text2molecule (me,
  94                                          ly_str02scm (to_str (num).ch_C ()),
  95                                          chain);
  96   Molecule d = Text_item::text2molecule (me,
  97                                          ly_str02scm (to_str (den).ch_C ()),
  98                                          chain);
  99   n.align_to (X_AXIS, CENTER);
 100   d.align_to (X_AXIS, CENTER);
 101   Molecule m;
 102   if (den)
 103     {
 104       m.add_at_edge (Y_AXIS, UP, n, 0.0);
 105       m.add_at_edge (Y_AXIS, DOWN, d, 0.0);
 106     }
 107   else
 108     {
 109       m = n;
 110       m.align_to (Y_AXIS, CENTER);
 111     }
 112   return m;
 113 }
 114