Table of Contents

Class MusicMath

Namespace
Celeritas.Core
Assembly
Celeritas.dll

Bulk pitch/velocity/timing operations over a NoteBuffer, plus MIDI note-name conversions. Timing is in whole-note units.

public static class MusicMath
Inheritance
MusicMath
Inherited Members

Methods

MidiToNoteName(int)

Convert MIDI pitch to note name (e.g., 60 -> "C4").

public static string MidiToNoteName(int midiPitch)

Parameters

midiPitch int

Returns

string

NoteNameToMidi(string)

Convert note name to MIDI pitch (e.g., "C4" -> 60).

public static int NoteNameToMidi(string noteName)

Parameters

noteName string

Returns

int

Exceptions

ArgumentNullException

noteName is null.

Quantize(NoteBuffer, Rational)

Quantize note start times to a grid (round to nearest grid step, half-way cases round up).

public static void Quantize(NoteBuffer buffer, Rational grid)

Parameters

buffer NoteBuffer
grid Rational

Remarks

Start times only: a note keeps the length it had, so on a grid coarser than the material it still ends off the grid. And notes closer together than one grid step land on the same step and sound together — four sixteenths quantized to a quarter become two pairs — which is what quantizing to that grid means, not a fault in the arithmetic. Choose a grid no coarser than the shortest note that should stay distinct.

Exceptions

ArgumentNullException

buffer is null.

ScaleVelocity(NoteBuffer, float)

SIMD scaling of velocity, using a portable Vector<T> loop that the JIT widens to the platform's widest vector unit.

The result is clamped into Velocity's documented 0..1 range, so a factor of 2 saturates rather than storing a loudness the type says cannot exist. That makes the operation lossy at the ends: scaling up and back down does not restore the original velocities. 

public static void ScaleVelocity(NoteBuffer buffer, float factor)

Parameters

buffer NoteBuffer
factor float

Exceptions

ArgumentNullException

buffer is null.

ArgumentException

factor is NaN.

Transpose(NoteBuffer, int)

Adds semitones to every pitch. Results are NOT clamped to the MIDI 0-127 range; callers that need valid MIDI pitches must clamp afterwards.

Rests are left where they are: RestPitch is silence, and silence has no pitch to move. Because that value is reserved, a note transposed exactly onto it reads as a rest from then on — clamp, or transpose back, before analysing a buffer that has been moved below the bottom of the keyboard.

The single-note reading takes the other contract: pitch.Transpose(ChromaticInterval) throws when the pitch or the result leaves 0-127. This one moves a whole buffer and cannot stop partway through, so it moves everything and leaves the range to the caller. 

public static void Transpose(NoteBuffer buffer, int semitones)

Parameters

buffer NoteBuffer
semitones int

Exceptions

ArgumentNullException

buffer is null.