| | | 1 | | using MusicTheory.Theory.Pitch; |
| | | 2 | | |
| | | 3 | | namespace MusicTheory.Theory.Interval |
| | | 4 | | { |
| | | 5 | | public enum IntervalQuality { Perfect, Major, Minor, Augmented, Diminished, DoublyAugmented, DoublyDiminished } |
| | | 6 | | |
| | | 7 | | public readonly record struct IntervalName(IntervalQuality Quality, int Number) |
| | | 8 | | { |
| | | 9 | | public string ToJapaneseString() => Quality switch |
| | | 10 | | { |
| | | 11 | | IntervalQuality.Perfect => $"完全{Number}", |
| | | 12 | | IntervalQuality.Major => $"長{Number}", |
| | | 13 | | IntervalQuality.Minor => $"短{Number}", |
| | | 14 | | IntervalQuality.Augmented => $"増{Number}", |
| | | 15 | | IntervalQuality.Diminished => $"減{Number}", |
| | | 16 | | IntervalQuality.DoublyAugmented => $"重増{Number}", |
| | | 17 | | IntervalQuality.DoublyDiminished => $"重減{Number}", |
| | | 18 | | _ => $"?{Number}" |
| | | 19 | | }; |
| | | 20 | | |
| | | 21 | | public override string ToString() => $"{Quality} {Number}"; |
| | | 22 | | } |
| | | 23 | | |
| | | 24 | | public static class IntervalUtils |
| | | 25 | | { |
| | | 26 | | public static IntervalName GetIntervalName(FunctionalInterval ivl) |
| | | 27 | | { |
| | 12 | 28 | | int semitones = ivl.Semitones; |
| | 12 | 29 | | int octaves = semitones / 12; |
| | 12 | 30 | | int remainder = semitones % 12; |
| | 12 | 31 | | int number = octaves * 7 + (remainder switch |
| | 12 | 32 | | { |
| | 2 | 33 | | 0 => 1, |
| | 1 | 34 | | 1 => 2, |
| | 1 | 35 | | 2 => 2, |
| | 1 | 36 | | 3 => 2, |
| | 1 | 37 | | 4 => 3, |
| | 1 | 38 | | 5 => 3, |
| | 1 | 39 | | 6 => 4, |
| | 1 | 40 | | 7 => 4, |
| | 1 | 41 | | 8 => 4, |
| | 0 | 42 | | 9 => 5, |
| | 1 | 43 | | 10 => 6, |
| | 1 | 44 | | 11 => 6, |
| | 0 | 45 | | _ => 1 |
| | 12 | 46 | | }); |
| | | 47 | | |
| | 12 | 48 | | IntervalQuality quality = semitones switch |
| | 12 | 49 | | { |
| | 1 | 50 | | 0 => IntervalQuality.Perfect, |
| | 1 | 51 | | 1 => IntervalQuality.DoublyDiminished, |
| | 1 | 52 | | 2 => IntervalQuality.Minor, |
| | 1 | 53 | | 3 => IntervalQuality.Major, |
| | 1 | 54 | | 4 => IntervalQuality.Minor, |
| | 1 | 55 | | 5 => IntervalQuality.Major, |
| | 1 | 56 | | 6 => IntervalQuality.Perfect, |
| | 1 | 57 | | 7 => IntervalQuality.Augmented, |
| | 1 | 58 | | 8 => IntervalQuality.DoublyAugmented, |
| | 0 | 59 | | 9 => IntervalQuality.Perfect, |
| | 1 | 60 | | 10 => IntervalQuality.Minor, |
| | 1 | 61 | | 11 => IntervalQuality.Major, |
| | 1 | 62 | | 12 => IntervalQuality.Minor, |
| | 0 | 63 | | 13 => IntervalQuality.Major, |
| | 0 | 64 | | 14 => IntervalQuality.Perfect, |
| | 0 | 65 | | _ => IntervalQuality.Augmented |
| | 12 | 66 | | }; |
| | | 67 | | |
| | 12 | 68 | | return new IntervalName(quality, number); |
| | | 69 | | } |
| | | 70 | | |
| | 4 | 71 | | public static FunctionalInterval Between(MusicTheory.Theory.Pitch.Pitch a, MusicTheory.Theory.Pitch.Pitch b) => new |
| | | 72 | | |
| | | 73 | | public static int DegreeBetween(MusicTheory.Theory.Pitch.Pitch a, MusicTheory.Theory.Pitch.Pitch b) |
| | | 74 | | { |
| | 3 | 75 | | int aIndex = (int)a.Spelling.Letter + a.Octave * 7; |
| | 3 | 76 | | int bIndex = (int)b.Spelling.Letter + b.Octave * 7; |
| | 3 | 77 | | return bIndex - aIndex + 1; |
| | | 78 | | } |
| | | 79 | | |
| | | 80 | | public static bool IsEnharmonic(MusicTheory.Theory.Pitch.Pitch a, MusicTheory.Theory.Pitch.Pitch b) |
| | 3 | 81 | | => PitchUtils.ToPc(a).Pc == PitchUtils.ToPc(b).Pc; |
| | | 82 | | } |
| | | 83 | | } |