2 pitch-scheme.cc -- implement scheme functions for Pitch
4 source file of the GNU LilyPond music typesetter
6 (c) 2005--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
11 LY_DEFINE (ly_pitch_transpose, "ly:pitch-transpose",
12 2, 0, 0, (SCM p, SCM delta),
13 "Transpose @var{p} by the amount @var{delta}, "
14 "where @var{delta} is relative to middle C.")
16 LY_ASSERT_SMOB (Pitch, p, 1);
17 LY_ASSERT_SMOB (Pitch, delta, 2);
19 Pitch *t = unsmob_pitch (p);
20 Pitch *d = unsmob_pitch (delta);
21 return t->transposed (*d).smobbed_copy ();
24 /* Should add optional args. */
25 LY_DEFINE (ly_make_pitch, "ly:make-pitch",
26 2, 1, 0, (SCM octave, SCM note, SCM alter),
27 "@var{octave} is specified by an integer, "
28 "zero for the octave containing middle C. "
29 "@var{note} is a number from 0 to 6, "
30 "with 0 corresponding to C and 6 corresponding to B. "
31 "The @var{alter} is a rational number of whole tones for alteration.")
33 LY_ASSERT_TYPE (scm_is_integer, octave, 1);
34 LY_ASSERT_TYPE (scm_is_integer, note, 2);
35 LY_ASSERT_TYPE (scm_is_rational, alter, 3);
37 Pitch p (scm_to_int (octave), scm_to_int (note),
38 ly_scm2rational (alter));
40 return p.smobbed_copy ();
43 LY_DEFINE (ly_pitch_negate, "ly:pitch-negate", 1, 0, 0,
47 LY_ASSERT_SMOB (Pitch, p, 1);
48 Pitch *pp = unsmob_pitch (p);
49 return pp->negated ().smobbed_copy ();
52 LY_DEFINE (ly_pitch_steps, "ly:pitch-steps", 1, 0, 0,
54 "Number of steps counted from middle C of the pitch @var{p}.")
56 LY_ASSERT_SMOB (Pitch, p, 1);
57 Pitch *pp = unsmob_pitch (p);
58 return scm_from_int (pp->steps ());
61 LY_DEFINE (ly_pitch_octave, "ly:pitch-octave",
63 "Extract the octave from pitch @var{p}.")
65 LY_ASSERT_SMOB (Pitch, pp, 1);
66 Pitch *p = unsmob_pitch (pp);
67 int q = p->get_octave ();
68 return scm_from_int (q);
71 LY_DEFINE (ly_pitch_alteration, "ly:pitch-alteration",
73 "Extract the alteration from pitch @var{p}.")
75 LY_ASSERT_SMOB (Pitch, pp, 1);
76 Pitch *p = unsmob_pitch (pp);
77 Rational q = p->get_alteration ();
79 return ly_rational2scm (q);
82 LY_DEFINE (pitch_notename, "ly:pitch-notename",
84 "Extract the note name from pitch @var{pp}.")
86 LY_ASSERT_SMOB (Pitch, pp, 1);
87 Pitch *p = unsmob_pitch (pp);
88 int q = p->get_notename ();
89 return scm_from_int (q);
92 LY_DEFINE (ly_pitch_quartertones, "ly:pitch-quartertones",
94 "Calculate the number of quarter tones of @var{p} from middle C.")
96 LY_ASSERT_SMOB (Pitch, pp, 1);
97 Pitch *p = unsmob_pitch (pp);
98 int q = p->rounded_quartertone_pitch ();
99 return scm_from_int (q);
102 LY_DEFINE (ly_pitch_semitones, "ly:pitch-semitones",
104 "calculate the number of semitones of @var{p} from middle C.")
106 LY_ASSERT_SMOB (Pitch, pp, 1);
107 Pitch *p = unsmob_pitch (pp);
108 int q = p->rounded_semitone_pitch ();
109 return scm_from_int (q);
112 LY_DEFINE (ly_pitch_less_p, "ly:pitch<?",
113 2, 0, 0, (SCM p1, SCM p2),
114 "Is @var{p1} lexicographically smaller than @var{p2}?")
116 LY_ASSERT_SMOB (Pitch, p1, 1);
117 LY_ASSERT_SMOB (Pitch, p2, 2);
119 Pitch *a = unsmob_pitch (p1);
120 Pitch *b = unsmob_pitch (p2);
122 if (Pitch::compare (*a, *b) < 0)
128 LY_DEFINE (ly_pitch_diff, "ly:pitch-diff",
129 2, 0, 0, (SCM pitch, SCM root),
130 "Return pitch @var{delta} such that @code{pitch} transposed by "
131 "@var{delta} equals @var{root}")
134 LY_ASSERT_SMOB (Pitch, pitch, 1);
135 LY_ASSERT_SMOB (Pitch, root, 2);
137 Pitch *p = unsmob_pitch (pitch);
138 Pitch *r = unsmob_pitch (root);
140 return pitch_interval (*r, *p).smobbed_copy ();