lily/duration.cc

   1 /*
   2   duration.cc -- implement Duration, Plet,
   3
   4   source file of the LilyPond music typesetter
   5
   6   (c)  1997--2001 Jan Nieuwenhuizen <janneke@gnu.org>
   7            Han-Wen Nienhuys <hanwen@cs.uu.nl>
   8
   9 */
  10
  11 #include <assert.h>
  12
  13 #include "lily-proto.hh"
  14 #include "string.hh"
  15 #include "moment.hh"
  16 #include "duration.hh"
  17 #include "ly-smobs.icc"
  18
  19
  20
  21 int
  22 Duration::compare (Duration const &left, Duration const &right)
  23 {
  24   return Rational::compare (left.length_mom (), right.length_mom ());
  25 }
  26
  27 Duration::Duration ()
  28 {
  29   durlog_i_ = 0;
  30   dots_i_ = 0;
  31   factor_ = Moment (1,1);
  32 }
  33
  34 Duration::Duration (int l, int d)
  35 {
  36   durlog_i_ = l;
  37   dots_i_ = d;
  38   factor_ = Moment (1,1);
  39 }
  40
  41 Duration
  42 Duration::compressed (Rational m) const
  43 {
  44   Duration d (*this);
  45   d.factor_ *= m;
  46   return d;
  47 }
  48
  49 Rational
  50 Duration::length_mom () const
  51 {
  52   Rational mom (1 << abs (durlog_i_));
  53
  54   if (durlog_i_> 0)
  55     mom = Moment (1)/mom;
  56
  57   Rational delta = mom;
  58
  59   for (int d = dots_i_; d; d--)
  60     {
  61       delta /= Moment (2);
  62       mom += delta;
  63     }
  64
  65   return mom * factor_;
  66 }
  67
  68
  69
  70 String
  71 Duration::str () const
  72 {
  73   String s =  to_str (durlog_i_) + to_str ('.', dots_i_);
  74   if (factor_ != Moment (1,1))
  75     {
  76       s += "*" + factor_.str ();
  77     }
  78   return s;
  79 }
  80
  81
  82 IMPLEMENT_TYPE_P (Duration, "duration?");
  83 IMPLEMENT_UNSMOB (Duration, duration);
  84
  85 SCM
  86 Duration::mark_smob (SCM)
  87 {
  88   return SCM_EOL;
  89 }
  90
  91 IMPLEMENT_SIMPLE_SMOBS (Duration);
  92
  93
  94 int
  95 Duration::print_smob (SCM s, SCM port, scm_print_state *)
  96 {
  97   Duration  *r = (Duration *) gh_cdr (s);
  98
  99   scm_puts ("#<Duration ", port);
 100   scm_display (ly_str02scm (r->str ().ch_C ()), port);
 101   scm_puts (" >", port);
 102
 103   return 1;
 104 }
 105
 106 SCM
 107 Duration::equal_p (SCM a , SCM b)
 108 {
 109   Duration  *p = (Duration *) gh_cdr (a);
 110   Duration  *q = (Duration *) gh_cdr (b);
 111
 112   bool eq = p->dots_i_ == q->dots_i_
 113     && p->durlog_i_ == q->durlog_i_
 114     && p->factor_ == q->factor_;
 115
 116   return eq ? SCM_BOOL_T : SCM_BOOL_F;
 117 }
 118
 119 MAKE_SCHEME_CALLBACK (Duration, less_p, 2);
 120 SCM
 121 Duration::less_p (SCM p1, SCM p2)
 122 {
 123   Duration *a = unsmob_duration (p1);
 124   Duration *b = unsmob_duration (p2);
 125
 126   if (compare (*a, *b) < 0)
 127     return SCM_BOOL_T;
 128   else
 129     return SCM_BOOL_F;
 130 }
 131
 132 static SCM
 133 make_duration (SCM l, SCM d)
 134 {
 135   Duration p (gh_scm2int (l), gh_scm2int (d));
 136   return p.smobbed_copy ();
 137 }
 138
 139 static void
 140 add_funcs ()
 141 {
 142   scm_make_gsubr ("make-duration", 2, 0, 0, (Scheme_function_unknown)make_duration);
 143 }
 144
 145 ADD_SCM_INIT_FUNC (duration, add_funcs);
 146
 147 SCM
 148 Duration::smobbed_copy ()const
 149 {
 150   Duration *  p = new Duration (*this);
 151   return p->smobbed_self ();
 152 }
 153
 154 int
 155 Duration::duration_log () const
 156 {
 157   return durlog_i_;
 158 }
 159
 160 int
 161 Duration::dot_count () const
 162 {
 163   return dots_i_;
 164 }
 165