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local lua_sig = pd.Class:new():register("lua_sig")
function lua_sig:initialize(sel, atoms)
self.inlets = {SIGNAL}
self.outlets = {SIGNAL}
self.phase = 0
self.freq = 220
self.amp = 0.5
return true
end
-- dsp method is called when processing is about to start
function lua_sig:dsp(samplerate, blocksize)
self.samplerate = samplerate
end
-- message to set frequency...
function lua_sig:in_1_freq(atoms)
self.freq = atoms[1]
end
-- ... and amplitude.
function lua_sig:in_1_amp(atoms)
self.amp = atoms[1]
end
-- perform method gets called with a table for each signal inlet
-- you must return a table for each signal outlet
function lua_sig:perform(in1)
local frequency = self.freq -- frequency of the sine wave in Hz
local amplitude = self.amp -- amplitude of the sine wave (0 to 1)
-- Calculate the angular frequency (in radians per sample)
local angular_freq = 2 * math.pi * frequency / self.samplerate
-- Loop through each sample index
for i = 1, #in1 do
-- NOTE: We ignore the input signal in this example. Try multiplying by
-- in1[i] for an amplitude/ring modulation effect.
in1[i] = amplitude * math.sin(self.phase)
self.phase = self.phase + angular_freq
if self.phase >= 2 * math.pi then
self.phase = self.phase - 2 * math.pi
end
end
return in1
end
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