CircleOfFiths

CircleOfFiths

Cirlce of Fifths Wave Generator

Generates waves using the Circle of Fifths

Parameters

Start

The starting point along the circle of fifths

required	type	position	pipeline	wildcard	aliases
false	Object	1	false	false

NoteCount

The note count (by default, 13)

required	type	position	pipeline	wildcard	aliases
false	Int32	2	false	false

Octave

Play in octave 3 by default

required	type	position	pipeline	wildcard	aliases
false	Int32	3	false	false

Duration

The note timing

required	type	position	pipeline	wildcard	aliases
false	TimeSpan	4	false	false

View Source

<#
.SYNOPSIS
    Cirlce of Fifths Wave Generator
.DESCRIPTION
    Generates waves using the Circle of Fifths
.LINK
    https://en.wikipedia.org/wiki/Circle_of_fifths
.NOTES
#>
param(
# The starting point along the circle of fifths
$Start = 0,

# The note count (by default, 13)
[int]
$NoteCount =  13,

# Play in octave 3 by default
[int]
$Octave = 3,

# The note timing
[Alias('bpm')]
[timespan]
$Duration = ([TimeSpan]::FromSeconds(60/128))
)

$noteSequence = 'C','G','D','A','E','B','F#', 'C#','A','E','B'

$currentWave = $this
if (-not $currentWave) {
    $currentWave = wave
}

if ($start -is [int]) {
    $startIndex = $start
}

if ($start -is [string]) {
    for ($startIndex = 0; $startIndex -lt $noteSequence.Length; $startIndex++) {
        if ($start -eq $noteSequence[$startIndex]) {
            break        
        }
    }
}
$noteFrequency = $currentWave.NoteFrequency
[Collections.IDictionary[]]$tune = 
    for ($index = $startIndex; $index -lt ($startIndex + $NoteCount); $index++) {
        
        $noteIndex =  $index % $noteSequence.Length
        
        $letterNote = $noteSequence[$noteIndex] -replace 
            '(?<=\p{L})', $Octave -replace 
            '(?<d>\d)\#', '#${d}'
        
        [Ordered]@{
            Name = 'LetterNote'
            Letter = $letterNote
            Octave = $Octave
            Frequency = $noteFrequency[$letterNote -replace '#', '♯']
            Duration = $Duration
        }
    }
    
$currentWave.Melody += $tune
return $currentWave.Sound()