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local bar = pd.Class:new():register("bar~")
function bar:initialize(sel, atoms)
self.outlets = {SIGNAL}
self.phase = 0
self.cycle = 0
self.freq = 233
return true
end
function bar:dsp(samplerate, blocksize)
self.samplerate = samplerate
self.blocksize = blocksize
end
function bar:random_walk(dmin, dmax)
self.cycle = self.cycle + 1
if self.cycle > 100 then
self.freq = self.freq + math.random(-1, 1)*math.random(dmin, dmax)
self.freq = math.min(600, math.max(150, self.freq))
self.cycle = 0
end
end
function bar:perform()
-- random frequency change
local dmin, dmax = 30, 70
self:random_walk(dmin, dmax)
local freq, a, b = self.freq, 0.4, 0.08
local out = {} -- result table
-- random phase offset
local d = b * math.random()
for i = 1, self.blocksize do
-- phase in radians
local x = 2 * math.pi * (self.phase + d)
out[i] = a * math.sin(x)
self.phase = self.phase + freq / self.samplerate
if self.phase >= 1 then
self.phase = self.phase - 1
end
end
return out
end
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