public Tone ComputeSecondToneOfInterval(Tone firstTone, GeneralInterval itv)
{
int sumOfHalftones = 0;
Tone targetTone = firstTone;
Tone startingToneReference = firstTone.ReferenceTone;
if (firstTone.ChromaticChange == -1)
{
targetTone = startingToneReference;
sumOfHalftones += 1;
}
else if (firstTone.ChromaticChange == 1)
{
targetTone = startingToneReference;
sumOfHalftones -= 1;
}
for (int i = 1; i < itv.numeral; i++)
{
ToneRelationship nextBasicToneRelationship = this.GetBasicToneRelationship(targetTone);
targetTone = nextBasicToneRelationship.Tone2;
sumOfHalftones += nextBasicToneRelationship.NumberOfHalftones;
}
while (sumOfHalftones != itv.halftoneNumber)
{
ToneRelationship derivedToneRelationship = this.GetDerivedToneRelationship(targetTone, itv.halftoneNumber - sumOfHalftones);
targetTone = derivedToneRelationship.Tone2;
sumOfHalftones += derivedToneRelationship.NumberOfHalftones;
}
return(targetTone);
}
private ToneRelationship GetBasicToneRelationship(Tone tone)
{
for (int i = 0; i < tone.Neighbors.Count; i++)
{
ToneRelationship toneRelationship = tone.Neighbors.ElementAt(i);
if (ToneGraph.IsBasicTone(toneRelationship.Tone2))
{
return(toneRelationship);
}
}
return(null);
}
private ToneRelationship GetDerivedToneRelationship(Tone tone, int halftoneDifference)
{
for (int i = 0; i < tone.Neighbors.Count; i++)
{
ToneRelationship toneRelationship = tone.Neighbors.ElementAt(i);
if (!ToneGraph.IsBasicTone(toneRelationship.Tone2) &&
Math.Abs(halftoneDifference - toneRelationship.NumberOfHalftones) < Math.Abs(halftoneDifference))
{
return(toneRelationship);
}
}
return(null);
}