// find where to place a ratio on the scale
private int FindNextBestCandidate(List <IntervalRatio> toPlace, out int stepIdx)
{
stepIdx = -1;
int ratioIdx = -1;
double bestPlacediff = double.PositiveInfinity;
for (int i = 0; i < toPlace.Count; i++)
{
IntervalRatio ratio = toPlace[i];
// place ratio between smaller and greater entries
int idxStart = 0;
int idxEnd = 0;
FindValidRange(ratio, out idxStart, out idxEnd);
for (int j = idxStart; j <= idxEnd; j++)
{
var checkStep = scaleSteps[j];
if (checkStep.Ratio == null)
{
double diff = Math.Abs(ratio.Cents - checkStep.Cents);
if (diff < bestPlacediff)
{
ratioIdx = i;
stepIdx = j;
bestPlacediff = diff;
}
}
}
}
return(ratioIdx);
}
private void FindValidRange(IntervalRatio ratio, out int idxStart, out int idxEnd)
{
idxStart = 1; // we dont place anything on step 0, it is the root, no interval
idxEnd = scaleSteps.Length - 1;
// start at last placed ratio entry smaller than ratio
for (int i = scaleSteps.Length - 1; i >= 0; i--)
{
if (scaleSteps[i].Ratio != null && scaleSteps[i].Ratio.Cents < ratio.Cents)
{
idxStart = i;
break;
}
}
// end at 1st placed ratio entry greater than ratio
for (int i = 0; i < scaleSteps.Length; i++)
{
if (scaleSteps[i].Ratio != null && scaleSteps[i].Ratio.Cents > ratio.Cents)
{
idxEnd = i;
break;
}
}
}
public void PlaceRatios()
{
List <IntervalRatio> toPlace = new List <IntervalRatio>(refIntervalRatios);
// always place C on 1st entry, idx = 0
scaleSteps[0].Ratio = new IntervalRatio(1, 1, "P1", "C");
while (toPlace.Count > 0)
{
// find next best candidate
int stepIdx = -1;
int ratioIdx = FindNextBestCandidate(toPlace, out stepIdx);
if (stepIdx < 0)
{
break;
}
// place it
IntervalRatio ratio = toPlace[ratioIdx];
ScaleStep scaleStep = scaleSteps[stepIdx];
toPlace.RemoveAt(ratioIdx);
scaleStep.Ratio = ratio;
//## debug
//Console.WriteLine("placing ratio {0} {1:F2} @ {2} {3:F2}", ratio, ratio.Cents, stepIdx, scaleStep.Cents);
}
}