/// <summary>
/// Reverses the order of a sequence of notes for a randomly selected
/// chord in the given bar, or in a randomly selected bar if <paramref name="barIndex"/> is null.
/// <para> The revese operation is made in place locally to the selected chord.
/// The chord notes are determined by the logic in
/// <see cref="Bar.GetOverlappingNotesForChord(IChord, out IList{int})"/>.</para>
/// </summary>
/// <param name="melody"> The candidate melody to operate on.</param>
/// <param name="barIndex"> Index of the bar to do the reverse in. If no bar index supplied, then a random bar would be selected. </param>
private protected virtual void ReverseChordNotesMutation(MelodyCandidate melody, int?barIndex = null)
{
// initialize random generator
Random randomizer = new Random();
// if no specific bar has been requested then set it randomly
int selectedBarIndex = barIndex ?? randomizer.Next(melody.Bars.Count);
IBar selectedBar = melody.Bars[selectedBarIndex];
// select a random chord from within the selected bar
int randomChordIndex = randomizer.Next(selectedBar.Chords.Count);
IChord selectedChord = selectedBar.Chords[randomChordIndex];
// create a single chord element sequence
IChord[] chordsToReverse = new[] { selectedChord };
// delegate reverse operation to superclass
PermutateNotes(selectedBar, chordsToReverse, Permutation.Reversed);
}
private IChord ModifyChord(IChord chord, params string[] modifications)
{
bool prevArgModifiedChord = false;
int index = 0;
do
{
var argument = modifications[index].ToLowerInvariant();
if (argument.StartsWith("sus"))
{
chord.Suspend(Int32.Parse(argument.Substring(3)));
prevArgModifiedChord = true;
}
if (argument.StartsWith("add"))
{
chord.Add(Int32.Parse(argument.Substring(3)));
prevArgModifiedChord = true;
}
index++;
} while (prevArgModifiedChord && index < modifications.Length);
return(chord);
}
public bool Equals(IChord other) => ChordDefinition.Equals(other.ChordDefinition) && Key.Equals(other.Key);
public void UpdateChord(IChord chord)
{
_chordsRegistry.Update(chord, Owner.FromPrincipal(User));
}
public IUniqueItem AddChord(IChord chord)
{
return(_chordsRegistry.Add(chord, Owner.FromPrincipal(User)));
}
private (List <IStringInstrumentNotePosition> notePositions, bool isValidChord) IsChord(IChord chord, IList <IStringInstrumentNotePosition> notesPerString)
{
var notePositions = new List <IStringInstrumentNotePosition>();
foreach (var nps in notesPerString)
{
if (nps == null)
{
notePositions.Clear();
}
else
{
notePositions.Add(nps);
}
}
var isValid = chord.Notes.All(chordNote => notePositions.Any(t => t.Note.Equals(chordNote)));
return(notePositions, isValid);
}
private IStringInstrumentChord GetStringInstrumentChord(IStringInstrument stringInstrument, IChord chord)
{
var possibilities = new List <IStringInstrumentChordPossibility>();
var ret = new StringInstrumentChord();
ret.Chord = chord;
// semi tone index.
for (var sti = 0; sti < stringInstrument.SemiToneCount; sti++)
{
// string note index.
var stringNotePositions = stringInstrument.Strings
.Select(currentString =>
{
var notePositions = stringNotePositionForString(currentString, chord, sti, _typicalFingerSemiToneStretch);
return(notePositions);
})
.ToList();
stringNotePositions.ForEach(t => t.Insert(0, null));
var allCombinations = Combos(stringNotePositions);
var combinationCases = allCombinations
.Select(t => IsChord(chord, t))
.ToList();
var tempPossibilities = combinationCases
.Where(t => t.isValidChord)
.Select(t => new StringInstrumentChordPossibility
{
NotePositions = t.notePositions
});
possibilities.AddRange(tempPossibilities);
}
ret.ChordPossibilities = possibilities
.Aggregate(new List <IStringInstrumentChordPossibility>(), (prev, current) =>
{
if (!prev.Any(t => t.Equals(current)))
{
prev.Add(current);
}
return(prev);
});
return(ret);
}
/// <summary>
/// Returns notes that sound "good" under the given chord and pitch range restriction.
/// </summary>
/// <param name="chord"> he requested chrod to map the notes against. </param>
/// <param name="mappingSource"> The mapping source - either scale notes or the chord's arpeggio notes. </param>
/// <param name="minPitch"> Lower bound pitch range constraint for the mapped notes. </param>
/// <param name="maxPitch"> Upper bound pitch range constraint for the mapped notes. </param>
/// <returns> Notes that sound "good" under the given chord, mapping source, and pitch range restriction. </returns>
internal static IEnumerable <NotePitch> GetNotes(IChord chord, ChordNoteMappingSource mappingSource, NotePitch minPitch, NotePitch maxPitch)
{
// build the scale (sequence of intervals from the chord's root note)
var rootNote = ConvertToExternalNoteName(chord.ChordRoot);
Scale scale = null;
switch (chord.ChordType)
{
case ChordType.Diminished:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Three, Interval.Six }, rootNote);
}
else // diminished arppeigo with added 9th
{
scale = new Scale(new Interval[] { Interval.One, Interval.Two, Interval.Three, Interval.Six }, rootNote);
}
break;
case ChordType.Dominant7:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Three, Interval.Three, Interval.Two }, rootNote);
}
else // mixolydian scale with omitted 4th
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.Three, Interval.Two, Interval.One, Interval.Two }, rootNote);
}
break;
case ChordType.Dominant7b9:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Three, Interval.Three, Interval.Three, Interval.FromHalfSteps(-1) }, rootNote);
}
else // harmonic minor v scale with 6th omitted
{
scale = new Scale(new Interval[] { Interval.One, Interval.Three, Interval.One, Interval.Two, Interval.Three, Interval.Two }, rootNote);
}
break;
case ChordType.Dominant7Suspended4:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Five, Interval.Two, Interval.Three, Interval.Two }, rootNote);
}
else // mixolydian scale
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.One, Interval.Two, Interval.Two, Interval.One, Interval.Two }, rootNote);
}
break;
case ChordType.Dominant7Augmented5:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Four, Interval.Two, Interval.Two }, rootNote);
}
else // whole tone scale
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.Two, Interval.Two, Interval.Two, Interval.Two }, rootNote);
}
break;
case ChordType.Dominant7Sharped9:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Three, Interval.Three, Interval.Four, Interval.FromHalfSteps(-3) }, rootNote);
}
else // mixolydian #2 scale with omitted 4th
{
scale = new Scale(new Interval[] { Interval.Three, Interval.One, Interval.Three, Interval.Two, Interval.One, Interval.Two }, rootNote);
}
break;
case ChordType.HalfDiminished:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Three, Interval.Four, Interval.Two }, rootNote);
}
else // locrian mode scale with ommited 2nd
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Two, Interval.One, Interval.Two, Interval.Two, Interval.Two }, rootNote);
}
break;
case ChordType.Major:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Three, Interval.Five }, rootNote);
}
else // dorian major scale with omitted 4th and 7th
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.Three, Interval.Two, Interval.Three }, rootNote);
}
break;
case ChordType.Major7:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Three, Interval.Four, Interval.One }, rootNote);
}
else // dorian major scale with omitted 4th
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.Three, Interval.Two, Interval.Two, Interval.One }, rootNote);
}
break;
case ChordType.MajorAugmented5:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Four, Interval.Four }, rootNote);
}
else // lydian augmented scale
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.Two, Interval.Two, Interval.One, Interval.Two, Interval.One }, rootNote);
}
break;
case ChordType.MajorSuspended4:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Five, Interval.Two, Interval.Five }, rootNote);
}
else // mixolydian scale
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.One, Interval.Two, Interval.Two, Interval.One, Interval.Two }, rootNote);
}
break;
case ChordType.Minor:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Four, Interval.Five }, rootNote);
}
else // aeolian minor scale with omitted 2nd and 6th
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Two, Interval.Two, Interval.Three, Interval.Two }, rootNote);
}
break;
case ChordType.Minor6:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Four, Interval.Two, Interval.Three }, rootNote);
}
else // dorian minor scale with omitted 7th
{
scale = new Scale(new Interval[] { Interval.Two, Interval.One, Interval.Two, Interval.Two, Interval.Two, Interval.Three }, rootNote);
}
break;
case ChordType.Minor7:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Four, Interval.Three, Interval.Two }, rootNote);
}
else // aeolian minor scale with omitted 6th
{
scale = new Scale(new Interval[] { Interval.Two, Interval.One, Interval.Two, Interval.Two, Interval.Three, Interval.Two }, rootNote);
}
break;
case ChordType.MinorMajor7:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Three, Interval.Four, Interval.Four, Interval.One }, rootNote);
}
else // harmonic minor scale
{
scale = new Scale(new Interval[] { Interval.Two, Interval.One, Interval.Two, Interval.Two, Interval.One, Interval.Three, Interval.One }, rootNote);
}
break;
case ChordType.Major13:
if (mappingSource == ChordNoteMappingSource.Chord)
{
scale = new Scale(new Interval[] { Interval.Four, Interval.Three, Interval.Two, Interval.Three }, rootNote);
}
else // dorian major scale with omitted 4th and 7th
{
scale = new Scale(new Interval[] { Interval.Two, Interval.Two, Interval.Three, Interval.Two, Interval.Three }, rootNote);
}
break;
default:
break;
}
// get actual notes and filter out results according to range constraints
var result = from note in scale.GetNotes()
where (int)note.NoteNumber >= (byte)minPitch && (int)note.NoteNumber <= (byte) maxPitch
select(NotePitch)(int) note.NoteNumber;
return(result);
}
public IUniqueItem Add(IChord item, IUser owner)
{
throw new NotImplementedException();
}
public void Update(IChord item, IUser owner)
{
throw new NotImplementedException();
}
public IReadOnlyList <IChordTarget> GetItemsByChord(IChord chord)
{
throw new ArgumentException("Unable to find requested items: fake registry is always empty!", nameof(chord));
}
