X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fduration.cc;h=0b80b1ce1f33dba7ed7ec97910edfdd33913e5b7;hb=38d7d319eabc906e82fb42002678c6d42a23b6f7;hp=7eb75b54237dbcfeb5ec26f0f0f68887dd625007;hpb=bb36bac02a64770871780231ecc709cb18b20932;p=lilypond.git

diff --git a/lily/duration.cc b/lily/duration.cc
index 7eb75b5423..0b80b1ce1f 100644
--- a/lily/duration.cc
+++ b/lily/duration.cc
@@ -1,73 +1,173 @@
 /*
-  duration.cc -- implement Duration, Plet, 
+  duration.cc -- implement Duration
 
   source file of the LilyPond music typesetter
 
-  (c)  1997--2000 Jan Nieuwenhuizen <janneke@gnu.org>
-           Han-Wen Nienhuys <hanwen@cs.uu.nl>
-
+  (c) 1997--2009 Jan Nieuwenhuizen <janneke@gnu.org>
+  Han-Wen Nienhuys <hanwen@xs4all.nl>
 */
 
-#include <assert.h>
+#include "duration.hh"
 
+#include "misc.hh"
 #include "lily-proto.hh"
-#include "string.hh"
-#include "moment.hh"
-#include "duration.hh"
+
+#include "ly-smobs.icc"
+
+int
+Duration::compare (Duration const &left, Duration const &right)
+{
+  return Rational::compare (left.get_length (), right.get_length ());
+}
 
 Duration::Duration ()
 {
-  durlog_i_ = 0;
-  dots_i_ = 0;
-  tuplet_iso_i_ = 1;
-  tuplet_type_i_ = 1;
+  durlog_ = 0;
+  dots_ = 0;
+  factor_ = Rational (1, 1);
+}
+
+Duration::Duration (int log, int d)
+{
+  durlog_ = log;
+  dots_ = d;
+  factor_ = Rational (1, 1);
 }
 
-void
-Duration::compress (Rational m)
+Duration::Duration (Rational r, bool scale)
 {
-  tuplet_iso_i_  *= m.num_i ();
-  tuplet_type_i_ *= m.den_i (); 
+  factor_ = Rational (1, 1);
+
+  if (r.num () == 0.0)
+    {
+      durlog_ = 0;
+      dots_ = 0;
+    }
+  else
+    {
+      /* we want to find the integer k for which 2q/p > 2^k >= q/p.
+	 It's simple to check that k' = \floor \log q - \floor \log p
+	 satisfies the left inequality and is within a factor of 2 of
+	 satistying the right one. Therefore either k = k' or k = k'+1 */
+
+      int p = r.num ();
+      int q = r.den ();
+      int k = intlog2 (q) - intlog2 (p);
+      if (shift_left(p, k) < q)
+	k++;
+
+      assert (shift_left(p, k) >= q && shift_left(p, (k-1)) < q);
+
+      /* If we were to write out log (p/q) in base 2, then the position of the
+	 first non-zero bit (ie. k in our notation) would be the durlog
+	 and the number of consecutive 1s after that bit would be the number of
+	 dots */
+      p = shift_left(p, k) - q;
+      dots_ = 0;
+      while ((p *= 2) >= q)
+	{
+	  p -= q;
+	  dots_++;
+	}
+
+      /* we only go up to 64th notes */
+      if (k > 6)
+	{
+	  durlog_ = 6;
+	  dots_ = 0;
+	}
+      else
+	durlog_ = k;
+
+      if (scale || k > 6)
+	factor_ = r / get_length ();
+    }
+}
+
+Duration
+Duration::compressed (Rational m) const
+{
+  Duration d (*this);
+  d.factor_ *= m;
+  return d;
 }
 
 Rational
-Duration::length_mom () const
+Duration::get_length () const
 {
-  Rational mom (1 << abs (durlog_i_));
+  Rational mom (1 << abs (durlog_));
 
-  if (durlog_i_> 0)
-    mom = Moment (1)/mom;
+  if (durlog_ > 0)
+    mom = Rational (1) / mom;
 
   Rational delta = mom;
-
-  for (int d = dots_i_; d; d--)
+  for (int i = 0; i < dots_; i++)
     {
-      delta /= Moment (2);
+      delta /= Rational (2);
       mom += delta;
     }
 
-  return mom * Moment (tuplet_iso_i_, tuplet_type_i_);
+  return mom * factor_;
 }
 
-void
-Duration::set_plet (int i, int t)
+string
+Duration::to_string () const
 {
-  tuplet_iso_i_ = i; 
-  tuplet_type_i_ = t;
+  string s;
+
+  if (durlog_ < 0)
+    s = "log = " + ::to_string (durlog_);
+  else
+    s = ::to_string (1 << durlog_);
+
+  s += ::to_string ('.', dots_);
+  if (factor_ != Moment (Rational (1, 1)))
+    s += "*" + factor_.to_string ();
+  return s;
 }
 
+IMPLEMENT_TYPE_P (Duration, "ly:duration?");
 
-String
-Duration::str () const
+SCM
+Duration::mark_smob (SCM)
 {
-  return to_str (durlog_i_) + to_str ('.', dots_i_);
+  return SCM_EOL;
 }
 
+IMPLEMENT_SIMPLE_SMOBS (Duration);
+int
+Duration::print_smob (SCM s, SCM port, scm_print_state *)
+{
+  Duration *r = (Duration *) SCM_CELL_WORD_1 (s);
+
+  scm_puts ("#<Duration ", port);
+  scm_display (ly_string2scm (r->to_string ()), port);
+  scm_puts (" >", port);
 
-bool
-Duration::plet_b ()
+  return 1;
+}
+
+SCM
+Duration::equal_p (SCM a, SCM b)
 {
-  return tuplet_iso_i_ != 1 || tuplet_type_i_ != 1;
+  Duration *p = (Duration *) SCM_CELL_WORD_1 (a);
+  Duration *q = (Duration *) SCM_CELL_WORD_1 (b);
+
+  bool eq = p->dots_ == q->dots_
+    && p->durlog_ == q->durlog_
+    && p->factor_ == q->factor_;
+
+  return eq ? SCM_BOOL_T : SCM_BOOL_F;
 }
 
+int
+Duration::duration_log () const
+{
+  return durlog_;
+}
 
+int
+Duration::dot_count () const
+{
+  return dots_;
+}