public static async Task <ScaleFinderResultSet> FindScalesAsync(IScaleFinderOptions scaleFinderOptions, CancellationToken cancelToken)
{
if (null == scaleFinderOptions)
{
throw new ArgumentNullException("scaleFinderOptions");
}
InternalNote root = NoteUtils.ToInternalNote(scaleFinderOptions.RootNote);
IScale scale = scaleFinderOptions.Scale;
InternalNote[] notesInScale = NamedInterval.GetNotes(root, scale.Intervals);
ScaleFinderResultSet results = new ScaleFinderResultSet(scaleFinderOptions);
if (cancelToken.IsCancellationRequested)
{
return(results);
}
foreach (NoteNode startingNode in FindNodes(notesInScale[0], scaleFinderOptions))
{
await FindAllScalesAsync(results, startingNode, notesInScale, 1, startingNode.String, scaleFinderOptions, cancelToken);
}
return(results);
}
public static ScaleFinderResultSet FindScales(IScaleFinderOptions scaleFinderOptions)
{
CancellationTokenSource cts = new CancellationTokenSource();
Task <ScaleFinderResultSet> task = FindScalesAsync(scaleFinderOptions, cts.Token);
task.Wait();
return(task.Result);
}
private static IEnumerable <NoteNode> FindNodes(InternalNote targetNote, IScaleFinderOptions scaleFinderOptions)
{
for (int str = 0; str < scaleFinderOptions.Instrument.NumStrings; str++)
{
InternalNote rootNote = scaleFinderOptions.Tuning.RootNotes[str].InternalNote;
int fret = NoteUtils.GetShift(rootNote, targetNote);
while (fret <= scaleFinderOptions.MaxFret)
{
yield return(new NoteNode(str, fret, targetNote, null));
fret += 12;
}
}
}
public static bool ValidateScale(IEnumerable <MarkPosition> scaleMarks, IScaleFinderOptions scaleFinderOptions)
{
if (null == scaleMarks)
{
throw new ArgumentNullException("scaleMarks");
}
if (null == scaleFinderOptions)
{
throw new ArgumentNullException("scaleFinderOptions");
}
MarkAnalysis ma = ScaleAnalysis(scaleMarks, scaleFinderOptions.Instrument.NumStrings);
bool reachPass = ma.Reach <= scaleFinderOptions.MaxReach;
bool openPass = scaleFinderOptions.AllowOpenStrings ? true : !ma.HasOpenStrings;
bool mutePass = scaleFinderOptions.AllowMutedStrings ? true : !ma.HasMutedStrings;
return(reachPass && openPass && mutePass);
}
internal ScaleFinderResultSet(IScaleFinderOptions scaleFinderOptions)
{
ScaleFinderOptions = scaleFinderOptions;
_results = new List <ScaleFinderResult>();
}
private static async Task FindAllScalesAsync(ScaleFinderResultSet results, NoteNode noteNode, InternalNote[] targetNotes, int nextNote, int str, IScaleFinderOptions scaleFinderOptions, CancellationToken cancelToken)
{
if (cancelToken.IsCancellationRequested)
{
return;
}
IInstrument instrument = scaleFinderOptions.Instrument;
if (nextNote == targetNotes.Length) // Build a scale result
{
List <MarkPosition> marks = new List <MarkPosition>();
NoteNode nn = noteNode;
// Walk back up the tree to set the marks on the result and flag each target note
while (null != nn)
{
if (nn.Fret >= 0)
{
marks.Add(new MarkPosition(nn.String + 1, nn.Fret));
}
nn = nn.Parent;
}
results.AddResult(marks);
}
else if (str < instrument.NumStrings) // Keep building the tree
{
// Look at all the notes on the string
int startingFret = scaleFinderOptions.AllowOpenStrings ? 0 : 1;
if (null != noteNode && noteNode.String == str)
{
startingFret = noteNode.Fret + 1;
}
for (int fret = startingFret; fret <= scaleFinderOptions.MaxFret; fret++)
{
InternalNote note = NoteUtils.Shift(scaleFinderOptions.Tuning.RootNotes[str].InternalNote, fret);
// See if the note is the next target note
if (note == targetNotes[nextNote])
{
NoteNode child = new NoteNode(str, fret, note, noteNode); // Add found note
await FindAllScalesAsync(results, child, targetNotes, nextNote + 1, str, scaleFinderOptions, cancelToken); // Look for the next note on the same string
}
}
await FindAllScalesAsync(results, noteNode, targetNotes, nextNote, str + 1, scaleFinderOptions, cancelToken); // Look for the next note on the next string
}
}
