/// <summary>
/// Is this NotePair dissonant?
/// </summary>
/// <returns>Whether the NotePair is dissnont or not</returns>
public bool IsDissonant()
{
var cantusFirmusScaleDegree = _scaleDegreeEvaluator.GetScaleDegreeFromNote(CantusFirmusNote);
var counterPointScaleDegree = _scaleDegreeEvaluator.GetScaleDegreeFromNote(CounterPointNote);
return(cantusFirmusScaleDegree.IsDissonantWith(counterPointScaleDegree));
}
/// <summary>
/// Determines whether nor not the distance between two notes is a dissonant leap or not.
/// </summary>
/// <param name="currentNote">The current note</param>
/// <param name="nextNote">The next note</param>
/// <returns>Whether the distance between two notes is a dissonant leap or not</returns>
private bool IsDissonantLeap(
int currentNote,
int nextNote
)
{
if (_context.GetNoteMotionSpanFromNotes(currentNote, nextNote) != NoteMotionSpan.Leap)
{
return(false);
}
var currentScaleDegree = _scaleDegreeEvaluator.GetScaleDegreeFromNote(currentNote);
var nextScaleDegree = _scaleDegreeEvaluator.GetScaleDegreeFromNote(nextNote);
return(currentScaleDegree.IsDissonantWith(nextScaleDegree));
}
public void GetCorrectScaleDegree(int pitch, ScaleDegree expectedScaleDegree)
{
var scaleDegreeEvaluator = new ScaleDegreeEvaluator();
var scaleDegree = scaleDegreeEvaluator.GetScaleDegreeFromNote(pitch);
Assert.AreEqual(expectedScaleDegree, scaleDegree);
}
/// <inheritdoc />
/// <summary>
/// Evaluates a given composition for doubled notes.
/// </summary>
/// <param name="composition">The given composition to evaluate</param>
/// <returns>The composition's total error count</returns>
public int EvaluateComposition(Composition composition)
{
var errorCount = 0;
for (var index = 1; index < composition.GetNotePairs().Count; index++)
{
var notePair = composition.GetNotePairs()[index];
if (_scaleDegreeEvaluator.GetScaleDegreeFromNote(notePair.CantusFirmusNote) !=
_scaleDegreeEvaluator.GetScaleDegreeFromNote(notePair.CounterPointNote))
{
continue;
}
notePair.IsDetrimental = true;
errorCount += 1;
}
return(errorCount);
}
/// <inheritdoc />
/// <summary>
/// Decorates the composition based on the current and next notes.
/// </summary>
/// <param name="currentNote">The current note</param>
/// <param name="nextNote">The next note</param>
/// <returns>A list of decorative notes, possibly empty</returns>
protected override List <int> GetPossibleDecorations(int currentNote, int nextNote)
{
var currentScaleDegree = ScaleDegreeEvaluator.GetScaleDegreeFromNote(currentNote);
var nextScaleDegree = ScaleDegreeEvaluator.GetScaleDegreeFromNote(nextNote);
if (!currentScaleDegree.IsThirdWith(nextScaleDegree) || Random.Next(1, 3) % 2 != 0)
{
return(EmptyDecoration);
}
return(new List <int> {
(currentNote + nextNote) / 2
});
}
/// <summary>
/// CompositionContext constructor.
/// </summary>
/// <param name="previousNotes">The previous notes in the composition</param>
/// <param name="currentNotes">The current notes in the composition</param>
/// <param name="scaleDegreeEvaluator">ScaleDegreeEvaluator used to help initialize class properties</param>
public CompositionContext(NotePair previousNotes, NotePair currentNotes,
ScaleDegreeEvaluator scaleDegreeEvaluator)
{
CantusFirmusNoteScaleDegree = scaleDegreeEvaluator.GetScaleDegreeFromNote(currentNotes.CantusFirmusNote);
CantusFirmusNoteMotion = GetNoteMotionFromNotes(
previousNotes.CantusFirmusNote,
currentNotes.CantusFirmusNote
);
CantusFirmusNoteMotionSpan = GetNoteMotionSpanFromNotes(
previousNotes.CantusFirmusNote,
currentNotes.CantusFirmusNote
);
CounterPointNoteScaleDegree = scaleDegreeEvaluator.GetScaleDegreeFromNote(currentNotes.CounterPointNote);
CounterPointNoteMotion = GetNoteMotionFromNotes(
previousNotes.CounterPointNote,
currentNotes.CounterPointNote
);
CounterPointNoteMotionSpan = GetNoteMotionSpanFromNotes(
previousNotes.CounterPointNote,
currentNotes.CounterPointNote
);
}
/// <inheritdoc />
/// <summary>
/// Decorates the composition based on the current and next notes.
/// </summary>
/// <param name="currentNote">The current note</param>
/// <param name="nextNote">The next note</param>
/// <returns>A list of decorative notes, possibly empty</returns>
protected override List <int> GetPossibleDecorations(int currentNote, int nextNote)
{
var currentScaleDegree = ScaleDegreeEvaluator.GetScaleDegreeFromNote(currentNote);
var nextScaleDegree = ScaleDegreeEvaluator.GetScaleDegreeFromNote(nextNote);
if (!currentScaleDegree.IsAdjacentTo(nextScaleDegree) || Random.Next(1, 3) % 2 != 0)
{
return(EmptyDecoration);
}
if (currentNote < nextNote)
{
return(new List <int> {
currentNote + 1, currentNote - 1, currentNote
});
}
return(currentScaleDegree != ScaleDegree.Sixth
? new List <int> {
currentNote - 1, currentNote + 1, currentNote
}
: EmptyDecoration);
}
/// <summary>
/// Determines whether or not the given notes correctly resolve according to the ascending seventh rule.
/// </summary>
/// <param name="currentNote">The current note</param>
/// <param name="nextNote">The next note</param>
/// <param name="currentNoteArrivedFromNoteMotion">The note motion which the current note arrived from</param>
/// <returns>Whether the given notes correctly resolve</returns>
private bool IncorrectlyResolves(int currentNote, int nextNote, NoteMotion currentNoteArrivedFromNoteMotion)
{
return(_scaleDegreeEvaluator.GetScaleDegreeFromNote(currentNote) == ScaleDegree.Seventh &&
currentNoteArrivedFromNoteMotion == NoteMotion.Ascending &&
_scaleDegreeEvaluator.GetScaleDegreeFromNote(nextNote) != ScaleDegree.Root);
}