public static int CalculateFifths(int midiPitch, MajorAndMinorScaleFlags flags)
{
var fifths = 0;
var neutralScaleTonicMidiPitch = flags.IsMinor ? Pitch.A3.MidiPitch : Pitch.C4.MidiPitch;
var currentPitch = neutralScaleTonicMidiPitch;
while (currentPitch != midiPitch)
{
if (!flags.IsFlat)
{
if (currentPitch - midiPitch > Interval.PerfectFifth.Halftones)
{
currentPitch -= Interval.PerfectOctave.Halftones;
}
else
{
currentPitch += Interval.PerfectFifth.Halftones;
fifths++;
}
}
else
{
if (currentPitch - midiPitch < Interval.PerfectFifth.MakeDescending().Halftones)
{
currentPitch += Interval.PerfectOctave.Halftones;
}
else
{
currentPitch -= Interval.PerfectFifth.Halftones;
fifths--;
}
}
}
return(fifths % 12);
}
/// <summary>
/// Creates a score with just one staff (other staves can be added later).
/// </summary>
/// <returns>A new score</returns>
public static Score CreateOneStaffScore(Clef clef, Step tonic, MajorAndMinorScaleFlags flags)
{
var score = CreateOneStaffScore();
score.FirstStaff.Elements.Add(clef);
score.FirstStaff.Elements.Add(Key.FromTonic(tonic, flags));
return(score);
}
/// <summary>
/// Adds a new staff to the score.
/// </summary>
/// <param name="clef">Clef</param>
/// <param name="timeSignature">Time signature</param>
/// <param name="tonic">Tonic of key</param>
/// <param name="flags">Scale flags</param>
/// <returns>This score</returns>
public Score AddStaff(Clef clef, TimeSignature timeSignature, Step tonic, MajorAndMinorScaleFlags flags)
{
var staff = new Staff();
staff.Elements.Add(clef);
staff.Elements.Add(Key.FromTonic(tonic, flags));
Staves.Add(staff);
return(this);
}
public static int CalculateFifths(Step step, MajorAndMinorScaleFlags flags)
{
return(CalculateFifths(step.ToPitch(4).MidiPitch, flags));
}
/// <summary>
/// Creates a new instance of Key from given step.
/// </summary>
/// <param name="step"></param>
/// <param name="flags"></param>
/// <returns></returns>
public static Key FromTonic(Step step, MajorAndMinorScaleFlags flags)
{
return(new Key(CircleOfFifths.CalculateFifths(step, flags)));
}
/// <summary>
/// Creates a new instance of Key from given midi pitch.
/// </summary>
/// <param name="midiPitch">Midi pitch</param>
/// <param name="flags">Flags</param>
/// <returns>Key</returns>
public static Key FromMidiPitch(int midiPitch, MajorAndMinorScaleFlags flags)
{
return(new Key(CircleOfFifths.CalculateFifths(midiPitch, flags)));
}
