diff options
| -rw-r--r-- | applause.lua | 30 |
1 files changed, 17 insertions, 13 deletions
diff --git a/applause.lua b/applause.lua index 70aaf21..a52b617 100644 --- a/applause.lua +++ b/applause.lua @@ -375,41 +375,45 @@ end -- -- Ramp from 0 to 1 -function Stream.Phasor(freq) +function Stream.Phasor(freq, phase) + phase = phase or 0 + return ScanStream:new(freq, function(accu, f) - return ((accu or 0) + f/samplerate) % 1 + return ((accu or phase) + f/samplerate) % 1 end) end -- Saw tooth wave from -1 to 1 -function Stream.SawOsc(freq) +function Stream.SawOsc(freq, phase) + phase = (phase or 0)*2+1 + return ScanStream:new(freq, function(accu, f) - return ((accu or 1) + 2*f/samplerate) % 2 - end):sub(1) + return ((accu or phase) + 2*f/samplerate) % 2 + end):minus(1) end -function Stream.SinOsc(freq) - return Stream.Phasor(freq):mul(2*math.pi):sin() +function Stream.SinOsc(freq, phase) + return Stream.Phasor(freq, phase):mul(2*math.pi):sin() end Stream["\u{25CB}"] = Stream.SinOsc -- APL Circle -- Pulse between 0 and 1 in half a period (width = 0.5) -function Stream.PulseOsc(freq) - return Stream.Phasor(freq):map(function(x) +function Stream.PulseOsc(freq, phase) + return Stream.Phasor(freq, phase):map(function(x) return x < 0.5 and 1 or 0 end) end -function Stream.SqrOsc(freq) - return Stream.Phasor(freq):map(function(x) +function Stream.SqrOsc(freq, phase) + return Stream.Phasor(freq, phase):map(function(x) return x < 0.5 and 1 or -1 end) end -function Stream.TriOsc(freq) +function Stream.TriOsc(freq, phase) local abs = math.abs - return Stream.SawOsc(freq):map(function(x) + return Stream.SawOsc(freq, phase):map(function(x) return abs(x)*2 - 1 end) end |