lily/duration-scheme.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2010 Jan Nieuwenhuizen <janneke@gnu.org>
   5   Han-Wen Nienhuys <hanwen@xs4all.nl>
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "duration.hh"
  22 #include "misc.hh"
  23
  24 MAKE_SCHEME_CALLBACK (Duration, less_p, 2);
  25 SCM
  26 Duration::less_p (SCM p1, SCM p2)
  27 {
  28   Duration *a = unsmob_duration (p1);
  29   Duration *b = unsmob_duration (p2);
  30
  31   if (compare (*a, *b) < 0)
  32     return SCM_BOOL_T;
  33   else
  34     return SCM_BOOL_F;
  35 }
  36
  37 LY_DEFINE (ly_duration_less_p, "ly:duration<?",
  38            2, 0, 0, (SCM p1, SCM p2),
  39            "Is @var{p1} shorter than @var{p2}?")
  40 {
  41   LY_ASSERT_SMOB (Duration, p1, 1);
  42   LY_ASSERT_SMOB (Duration, p2, 2);
  43
  44   Duration *a = unsmob_duration (p1);
  45   Duration *b = unsmob_duration (p2);
  46
  47   if (Duration::compare (*a, *b) < 0)
  48     return SCM_BOOL_T;
  49   else
  50     return SCM_BOOL_F;
  51 }
  52
  53 LY_DEFINE (ly_make_duration, "ly:make-duration",
  54            1, 3, 0, (SCM length, SCM dotcount, SCM num, SCM den),
  55            "@var{length} is the negative logarithm (base 2) of the duration:"
  56            " 1@tie{}is a half note, 2@tie{}is a quarter note, 3@tie{}is an"
  57            " eighth note, etc.  The number of dots after the note is given by"
  58            " the optional argument @var{dotcount}.\n"
  59            "\n"
  60            "The duration factor is optionally given by @var{num} and"
  61            " @var{den}.\n"
  62            "\n"
  63            "A duration is a musical duration, i.e., a length of time"
  64            " described by a power of two (whole, half, quarter, etc.) and a"
  65            " number of augmentation dots.")
  66 {
  67   LY_ASSERT_TYPE (scm_is_integer, length, 1);
  68
  69   int dots = 0;
  70   if (dotcount != SCM_UNDEFINED)
  71     {
  72       LY_ASSERT_TYPE (scm_is_integer, dotcount, 2);
  73       dots = scm_to_int (dotcount);
  74     }
  75
  76   bool compress = false;
  77   if (num != SCM_UNDEFINED)
  78     {
  79       LY_ASSERT_TYPE (scm_is_number, num, 3);
  80       compress = true;
  81     }
  82   else
  83     num = scm_from_int (1);
  84
  85   if (den != SCM_UNDEFINED)
  86     {
  87       LY_ASSERT_TYPE (scm_is_number, den, 4);
  88       compress = true;
  89     }
  90   else
  91     den = scm_from_int (1);
  92
  93   Duration p (scm_to_int (length), dots);
  94   if (compress)
  95     p = p.compressed (Rational (scm_to_int (num), scm_to_int (den)));
  96
  97   return p.smobbed_copy ();
  98 }
  99
 100 LY_DEFINE (ly_duration_log, "ly:duration-log",
 101            1, 0, 0, (SCM dur),
 102            "Extract the duration log from @var{dur}.")
 103 {
 104   LY_ASSERT_SMOB (Duration, dur, 1);
 105   return scm_from_int (unsmob_duration (dur)->duration_log ());
 106 }
 107
 108 LY_DEFINE (ly_duration_dot_count, "ly:duration-dot-count",
 109            1, 0, 0, (SCM dur),
 110            "Extract the dot count from @var{dur}.")
 111 {
 112   LY_ASSERT_SMOB (Duration, dur, 1);
 113   return scm_from_int (unsmob_duration (dur)->dot_count ());
 114 }
 115
 116 LY_DEFINE (ly_intlog2, "ly:intlog2",
 117            1, 0, 0, (SCM d),
 118            "The 2-logarithm of 1/@var{d}.")
 119 {
 120   LY_ASSERT_TYPE (scm_is_number, d, 1);
 121   int log = intlog2 (scm_to_int (d));
 122   return scm_from_int (log);
 123 }
 124
 125 LY_DEFINE (ly_duration_length, "ly:duration-length",
 126            1, 0, 0, (SCM dur),
 127            "The length of the duration as a @code{moment}.")
 128 {
 129   LY_ASSERT_SMOB (Duration, dur, 1);
 130   return Moment (unsmob_duration (dur)->get_length ()).smobbed_copy ();
 131 }
 132
 133 LY_DEFINE (ly_duration_2_string, "ly:duration->string",
 134            1, 0, 0, (SCM dur),
 135            "Convert @var{dur} to a string.")
 136 {
 137   LY_ASSERT_SMOB (Duration, dur, 1);
 138   return ly_string2scm (unsmob_duration (dur)->to_string ());
 139 }
 140
 141 LY_DEFINE (ly_duration_factor, "ly:duration-factor",
 142            1, 0, 0, (SCM dur),
 143            "Extract the compression factor from @var{dur}."
 144            "  Return it as a pair.")
 145 {
 146   LY_ASSERT_SMOB (Duration, dur, 1);
 147   Rational r = unsmob_duration (dur)->factor ();
 148   return scm_cons (scm_from_int64 (r.num ()), scm_from_int64 (r.den ()));
 149 }