lily/time-description.cc

   1 /*
   2   time-description.cc -- implement Time_description
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--1998 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "time-description.hh"
  10 #include "debug.hh"
  11
  12 String
  13 Time_description::str () const
  14 {
  15   String s ("Time_description { ");
  16   if (cadenza_b_)
  17         s += String ("(") + _("cadenza") + ")";
  18   s += "at ";
  19   s += when_.str ();
  20   s +="\ntime_signature " + (whole_per_measure_/one_beat_).str () +":" +
  21          (Rational (Rational (1)/one_beat_)).str ();
  22   s += "\nposition " + to_str (bars_i_) + ":"+ whole_in_measure_.str () +"\n}\n";
  23   return s;
  24 }
  25
  26 void
  27 Time_description::print() const
  28 {
  29 #ifndef NPRINT
  30   DOUT << str ();
  31 #endif
  32 }
  33 void
  34 Time_description::OK() const
  35 {
  36 #ifndef NDEBUG
  37   if (!cadenza_b_)
  38         assert (whole_in_measure_ < whole_per_measure_);
  39   assert (Moment (0) <= whole_in_measure_);
  40   assert (one_beat_);
  41 #endif
  42 }
  43
  44 void
  45 Time_description::set_cadenza (bool b)
  46 {
  47   if (cadenza_b_ && !b)
  48     {
  49         if (whole_in_measure_)
  50           {
  51             bars_i_ ++;         // should do?
  52             whole_in_measure_ = 0;
  53           }
  54     }
  55   cadenza_b_ = b ;
  56 }
  57
  58 Time_description::Time_description()
  59 {
  60   error_b_ =  false;
  61   whole_per_measure_ = 1;
  62   whole_in_measure_ =0;
  63   one_beat_ = Moment (1,4);
  64   when_ = 0;
  65   bars_i_ = 1;                  // musician start counting at 1
  66   cadenza_b_ = false;
  67 }
  68
  69 void
  70 Time_description::add (Moment dt)
  71 {
  72   assert (dt >= Rational (0));
  73   when_ +=  dt;
  74   whole_in_measure_ += dt;
  75
  76   while (!cadenza_b_ && whole_in_measure_ >= whole_per_measure_)
  77     {
  78         whole_in_measure_ -= whole_per_measure_;
  79         bars_i_ ++;
  80     }
  81 }
  82
  83 void
  84 Time_description::set_time_signature (int l, int o)
  85 {
  86   assert (o);
  87   one_beat_ = Rational (1)/Moment (o);
  88   whole_per_measure_ = Moment (l) * one_beat_;
  89 }
  90
  91 bool
  92 Time_description::allow_time_signature_change_b()
  93 {
  94   return!(whole_in_measure_);
  95 }
  96
  97 /**
  98   retrieve error messages.
  99   @return
 100   error messages if not possible, "" if possible
 101   */
 102 String
 103 Time_description::try_set_partial_str (Moment p) const
 104 {
 105   if (p<Rational (0))
 106         return (_ ("partial measure must be non-negative"));
 107   if (p > whole_per_measure_)
 108         return (_ ("partial measure too large"));
 109   return "";
 110 }
 111
 112 void
 113 Time_description::setpartial (Moment p)
 114 {
 115   whole_in_measure_ = whole_per_measure_ - p;
 116 }
 117
 118 Moment
 119 Time_description::barleft() const
 120 {
 121   assert (!cadenza_b_);
 122   return whole_per_measure_-whole_in_measure_;
 123 }
 124
 125 int
 126 Time_description::compare (Time_description const &t1,  Time_description const&t2)
 127 {
 128   int i = sign (t1.when_-t2.when_);
 129
 130   if (!i)
 131     {
 132         assert (t1.bars_i_==t2.bars_i_);
 133         assert (t1.one_beat_ == t2.one_beat_);
 134         assert (t1.whole_in_measure_ == t2.whole_in_measure_);
 135         assert (t1.whole_per_measure_ == t2.whole_per_measure_);
 136     }
 137
 138   return i;
 139 }
 140
 141 Moment
 142 Time_description::next_bar_moment() const
 143 {
 144   return when_ + barleft();
 145 }