lily/midi-def.cc

   1 /*
   2   midi-def.cc -- implement Midi_def
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2001 Jan Nieuwenhuizen <janneke@gnu.org>
   7
   8 */
   9 #include <math.h>
  10 #include "misc.hh"
  11 #include "midi-def.hh"
  12 #include "performance.hh"
  13 #include "debug.hh"
  14 #include "scope.hh"
  15
  16 Midi_def::Midi_def ()
  17 {
  18   // ugh
  19   set_tempo (Moment (Rational (1, 4)), 60);
  20 }
  21
  22 int
  23 Midi_def::get_tempo_i (Moment one_beat_mom)
  24 {
  25   Moment w = *unsmob_moment (scope_p_->scm_elem ("whole-in-seconds"));
  26   Moment wholes_per_min = Moment (60) /w;
  27   int beats_per_min =  int ((wholes_per_min / one_beat_mom).main_part_);
  28   return int (beats_per_min);
  29 }
  30
  31 void
  32 Midi_def::set_tempo (Moment one_beat_mom, int beats_per_minute_i)
  33 {
  34   Moment beats_per_second = Moment (beats_per_minute_i) / Moment (60);
  35
  36   Moment m = Moment (1)/Moment (beats_per_second * one_beat_mom);
  37   scope_p_->set ("whole-in-seconds", m.smobbed_copy ());
  38 }
  39
  40
  41 int Midi_def::score_count_i_=0;
  42
  43 int
  44 Midi_def::get_next_score_count () const
  45 {
  46   return score_count_i_++;
  47 }
  48
  49 void
  50 Midi_def::reset_score_count ()
  51 {
  52   score_count_i_ = 0;
  53 }