X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fduration.cc;h=782804e9da31d90b610543c2570a2c71d744a3c7;hb=84cad110c3bbaeca8e5144dba7f8756b89100396;hp=7710e4dcc037d9a9c349674f67784c9adf65f434;hpb=11be23f380bcb249d49269cfa6f7889c6829011f;p=lilypond.git

diff --git a/lily/duration.cc b/lily/duration.cc
index 7710e4dcc0..782804e9da 100644
--- a/lily/duration.cc
+++ b/lily/duration.cc
@@ -1,99 +1,184 @@
 /*
-  duration.cc -- implement Duration, Plet, 
+  This file is part of LilyPond, the GNU music typesetter.
 
-  source file of the LilyPond music typesetter
+  Copyright (C) 1997--2012 Jan Nieuwenhuizen <janneke@gnu.org>
+  Han-Wen Nienhuys <hanwen@xs4all.nl>
 
-  (c)  1997--2000 Jan Nieuwenhuizen <janneke@gnu.org>
-           Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  LilyPond is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
 
+  LilyPond is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <assert.h>
+#include "duration.hh"
 
+#include "misc.hh"
 #include "lily-proto.hh"
-#include "string.hh"
-#include "moment.hh"
-#include "duration.hh"
 
-int
-compare (Array<Duration>* left, Array<Duration>* right)
-{
-  assert (left);
-  assert (right);
-  
-  if (left->size () == right->size ())
-    {
-      for (int i = 0; i < left->size (); i++)
-	{
-	  int r = Duration::compare ((*left)[i], (*right)[i]);
-	  if (r)
-	    return r;
-	}
-    }
-  else
-    return 1;
-  return 0;
-}
+#include "ly-smobs.icc"
 
 int
 Duration::compare (Duration const &left, Duration const &right)
 {
-  return Rational::compare (left.length_mom (), right.length_mom ());
+  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);
+}
+
+Duration::Duration (Rational r, bool scale)
+{
+  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 = (int) r.num ();
+      int q = (int) 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 ();
+    }
 }
 
-void
-Duration::compress (Rational m)
+Duration
+Duration::compressed (Rational m) const
 {
-  tuplet_iso_i_  *= m.num_i ();
-  tuplet_type_i_ *= m.den_i (); 
+  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);
 
-bool
-Duration::plet_b ()
+  scm_puts ("#<Duration ", port);
+  scm_display (ly_string2scm (r->to_string ()), port);
+  scm_puts (" >", port);
+
+  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_;
+}