/*
- duration.cc -- implement Duration, Plet,
+ duration.cc -- implement Duration
source file of the LilyPond music typesetter
- (c) 1997--1999 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_;
+}