/// <summary>
/// The rootPitch and all the pitches in the MidiChordDef must be contained in the gamut.
/// The vertical velocity sequence remains unchanged except when notes are removed because they are duplicates.
/// Calculates the number of steps to transpose, and then calls TransposeStepsInGamut.
/// When this function returns, rootPitch is the lowest pitch in both BasicMidiChordDefs[0] and NotatedMidiPitches.
/// </summary>
public void TransposeToRootInGamut(Gamut gamut, int rootPitch)
{
#region conditions
Debug.Assert(gamut != null);
Debug.Assert(gamut.Contains(rootPitch));
Debug.Assert(gamut.Contains(BasicMidiChordDefs[0].Pitches[0]));
#endregion conditions
int stepsToTranspose = gamut.IndexOf(rootPitch) - gamut.IndexOf(BasicMidiChordDefs[0].Pitches[0]);
// checks that all the pitches are in the gamut.
TransposeStepsInGamut(gamut, stepsToTranspose);
}
private byte DoTranspose(byte initialValue, Gamut gamut, int steps)
{
int index = gamut.IndexOf(initialValue);
int newIndex = index + steps;
newIndex = (newIndex >= 0) ? newIndex : 0;
newIndex = (newIndex < gamut.Count) ? newIndex : gamut.Count - 1;
return (byte)gamut[newIndex];
}
private void OppositePitches(Gamut gamut, Gamut oppositeGamut, List<byte> pitches)
{
for(int i = 0; i < pitches.Count; ++i)
{
int pitchIndex = gamut.IndexOf(pitches[i]);
// N.B. it is not necessarily true that gamut.Count == oppositeGamut.Count.
pitchIndex = (pitchIndex < oppositeGamut.Count) ? pitchIndex : oppositeGamut.Count - 1;
pitches[i] = (byte)oppositeGamut[pitchIndex];
}
}
