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Dubstep Dawn for Wavepot
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/** | |
* potasmic - dubstep dawn | |
* (because all other wavepot loops' names are part of the day hehehe) | |
**/ | |
var bpm = 148; | |
var tuning = 440; | |
var transpose = 0; | |
// constants | |
var tau = 2 * Math.PI; | |
// time coefficients | |
var t, tt; | |
function Osc(type, octave, size, alias){ | |
if (!(this instanceof Osc)) return new Osc(type, size, alias); | |
this.pos = 0; | |
this.octave = Math.pow(2,octave) || 1; | |
this.size = size || sampleRate; | |
this.coeff = this.size / sampleRate; | |
this.table = new Float32Array(this.size); | |
this.alias = alias === false ? false : true; | |
this.build(type); | |
} | |
Osc.prototype.build = function(type){ | |
switch (type) { | |
case 'sin': | |
var scale = 2 * Math.PI / this.size; | |
for (var i = 0; i < this.size; i++) { | |
this.table[i] = Math.sin(i * scale); | |
} | |
break; | |
case 'saw': | |
for (var i = 0; i < this.size; i++) { | |
var x = (i / this.size); | |
this.table[i] = +2.0 * (x - Math.round(x)); | |
} | |
break; | |
case 'ramp': | |
for (var i = 0; i < this.size; i++) { | |
var x = (i / this.size); | |
this.table[i] = -2.0 * (x - Math.round(x)); | |
} | |
break; | |
case 'tri': | |
for (var i = 0; i < this.size; i++) { | |
var x = (i / this.size) - 0.25; | |
this.table[i] = 1.0 - 4.0 * Math.abs(Math.round(x) - x); | |
} | |
break; | |
case 'sqr': | |
var half = this.size / 2; | |
for (var i = 0; i < this.size; i++) { | |
this.table[i] = i < half ? +1 : -1; | |
} | |
break; | |
} | |
}; | |
Osc.prototype.play = function(freq,oct){ | |
var octa = Math.pow(2,oct) || this.octave; | |
this.pos += freq * this.coeff * octa; | |
if (this.pos >= this.size) this.pos -= this.size; | |
this.index = this.pos | 0; | |
if (!this.alias) return this.table[this.index]; | |
this.alpha = this.pos - this.index; | |
this.next = this.table[this.index == this.size - 1 ? 0 : this.index + 1]; | |
this.curr = this.table[this.index]; | |
return this.curr + (this.next - this.curr) * this.alpha; | |
}; | |
function Syn(oscs, octs) { | |
if(!(this instanceof Syn)) return new Syn(oscs); | |
this.oscs = oscs; | |
this.octs = octs; | |
} | |
Syn.prototype.setOcts = function(arr) { | |
this.octs = arr; | |
} | |
Syn.prototype.mix = function(freq) { | |
var sum = 0; | |
var all = this.oscs.length; | |
for(var i=0; i< all; i++ ) { | |
var oct = this.octs[i]; | |
sum += this.oscs[i].play(freq,oct) * 1/all; | |
} | |
return sum; | |
} | |
function clock(_t){ | |
t = _t; | |
t *= bpm / 120; | |
tt = tau * t; | |
} | |
function sequence(measure, seq){ | |
return seq[(t / measure / 2 | 0) % seq.length]; | |
} | |
function ms2freq(ms) { | |
return (ms)*60/bpm; | |
} | |
function arp(measure, x, y, z){ | |
var ts = t / 2 % measure; | |
return Math.sin(x * (Math.exp(-ts * y))) * Math.exp(-ts * z); | |
} | |
function sin(freq, phase){ | |
return Math.sin((t * freq + (2 - (phase || 0) / 2)) * tau); | |
} | |
function saw(freq){ | |
return 1-2 * (t % (1 / freq)) * freq; | |
} | |
function tri(freq){ | |
return Math.abs(1 - (2 * t * freq) % 2) * 2 - 1; | |
} | |
function sqr(freq){ | |
return sin(freq, t) > 0 ? 1 : -1; | |
} | |
function Noise(){ | |
return Math.random() * 2 - 1; | |
} | |
function note(n, octave){ | |
return Math.pow(2, ( | |
n + transpose - 33 + (12 * (octave || 0)) | |
) / 12) * tuning; // A4 tuning | |
} | |
function clip(x){ | |
return x / (1 + Math.abs(x)); | |
} | |
function DiodeFilter(){ | |
this.k = 0; | |
this.A = 0; | |
this.z = [0,0,0,0,0]; | |
this.ah; | |
this.bh; | |
this.fc; | |
this.set_q(0); | |
this.set_hpf(0.5); | |
this.set_fc(.5); | |
} | |
DiodeFilter.prototype.set_hpf = function(fc){ | |
var K = fc * Math.PI; | |
this.ah = (K - 2) / (K + 2); | |
this.bh = 2 / (K + 2); | |
}; | |
DiodeFilter.prototype.reset = function(){ | |
if (this.k < 17) this.z = [0,0,0,0,0]; | |
}; | |
DiodeFilter.prototype.set_q = function(q){ | |
this.k = 20 * q; | |
this.A = 1 + 0.5 * this.k; | |
}; | |
DiodeFilter.prototype.set_fc = function(cutoff){ | |
cutoff = (cutoff * cutoff); | |
this.fc = cutoff <= 0 | |
? .02 | |
: (cutoff >= 1.0 ? .999 : cutoff); | |
}; | |
DiodeFilter.prototype.run = function(x){ | |
var a = Math.PI * this.fc; | |
a = 2 * Math.tan(0.5*a); // dewarping, not required with 2x oversampling | |
var ainv = 1 / a; | |
var a2 = a*a; | |
var b = 2*a + 1; | |
var b2 = b*b; | |
var c = 1 / (2*a2*a2 - 4*a2*b2 + b2*b2); | |
var g0 = 2*a2*a2*c; | |
var g = g0 * this.bh; | |
// current state | |
var s0 = (a2*a*this.z[0] + a2*b*this.z[1] + this.z[2]*(b2 - 2*a2)*a + this.z[3]*(b2 - 3*a2)*b) * c; | |
var s = this.bh*s0 - this.z[4]; | |
// solve feedback loop (linear) | |
var y5 = (g*x + s) / (1 + g*this.k); | |
// input clipping | |
var y0 = clip(x - this.k*y5); | |
y5 = g*y0 + s; | |
// compute integrator outputs | |
var y4 = g0*y0 + s0; | |
var y3 = (b*y4 - this.z[3]) * ainv; | |
var y2 = (b*y3 - a*y4 - this.z[2]) * ainv; | |
var y1 = (b*y2 - a*y3 - this.z[1]) * ainv; | |
// update filter state | |
this.z[0] += 4*a*(y0 - y1 + y2); | |
this.z[1] += 2*a*(y1 - 2*y2 + y3); | |
this.z[2] += 2*a*(y2 - 2*y3 + y4); | |
this.z[3] += 2*a*(y3 - 2*y4); | |
this.z[4] = this.bh*y4 + this.ah*y5; | |
return this.A*y4; | |
}; | |
// ----------------------------------------------------------- | |
var snare_patt = [ | |
0,0,0,0,0,0,0,0, | |
.3,0,0,0,0,0,0,0,//- | |
0,0,0,0,0,0,0,0, | |
.3,0,0,0,0,0,0,0,//- | |
0,0,0,0,0,0,0,0, | |
.3,0,0,0,0,0,0,0,//- | |
0,0,0,0,0,0,0,0, | |
.3,0,0,.3,0,0,.3,0//- | |
]; | |
var kick_patt = [ | |
1,0,0,0,0,0,0,0, | |
1,0,0,0,0,0,0,0,//- | |
1,0,0,1,0,0,1,0, | |
1,0,0,0,0,0,0,0,//- | |
1,0,0,0,0,0,0,0, | |
1,0,0,0,0,0,0,0,//- | |
1,0,0,1,0,0,1,0, | |
1,0,1,1,0,0,1,0//- | |
]; | |
var hat_patt = [ | |
0.01,0.1,0.5,0.01 | |
]; | |
var wob_state_init = [ | |
0,0,0,0,0,0,0,0, | |
0,0,0.25,0.5,1,1,1,1,//- | |
0,0,0,0,0,0,0,0, | |
0.25,0.5,1,0.5,1,0.5,1,0.5,//- | |
0,0,0,0,0,0,0,0, | |
0,0,0.25,0.5,1,1,1,1,//- | |
0,0,0,0,0,0,0,0, | |
1,1,1,1,1,1,1,1//- | |
]; | |
var wob_lfo = [ | |
8,8,8,8,16,16,16,16,8,8,8,8,4,4,16,8 | |
].map( function(n) { return ms2freq(n);} ); | |
var wob_note_init = [ | |
0,0,0,0,5,5,5,5,3,3,3,3,1,1,5,-2 | |
].map( function(n) { return note(n,1) }); | |
var wob_note_drop = [ | |
0,0,0,0,5,5,5,5,3,3,3,3,1,1,5,-2, | |
0,0,0,0,-2,-2,-2,-2,-3,-3,-3,-3,-4,-4,-2,-2, | |
0,0,0,0,-2,-2,-2,-2,3,3,3,3,2,2,3,2, | |
0,0,0,0,-2,-2,-2,-2,7,7,7,7,5,5,2,2 | |
].map( function(n) { return note(n,1) }); | |
var pling_note = [ | |
0,3,7,12,0,3,7,12,0,3,7,12,0,3,7,12, | |
5,9,12,17,5,9,12,17,5,9,12,17,5,9,12,17, | |
3,7,10,15,3,7,10,15,3,7,10,15,3,7,10,15, | |
1,5,8,13,1,5,8,13,1,5,8,13,1,5,8,13 | |
].map( function(n) {return note(n,1) }); | |
var fr8_note = [ | |
0,0,5,5,3,3,1,5 | |
].map( function(n) {return note(n,1) }); | |
var fr8_on = [ | |
0,0,1,0 | |
]; | |
var build_kick = [ | |
1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0, | |
1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0, | |
1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0, | |
1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1 | |
]; | |
// ------------------------------------------------------------- | |
//wobble setup | |
var wob_state, wob_note = [1]; | |
var osc1 = Osc('sqr'); | |
var osc2 = Osc('saw'); | |
var osc3 = Osc('saw'); | |
var fil = new DiodeFilter(); | |
fil.set_hpf(0.0); | |
fil.set_q(0.07); | |
var wobble = new Syn([osc1,osc2,osc3],[-1,0,-1]); | |
//hat setup | |
var hat_note = note(21,6); | |
var hat_osc = Osc('ramp'); | |
//pingplong setup | |
var arp1 = Osc('sqr'); | |
var arp2 = Osc('sin'); | |
var arp3 = Osc('saw'); | |
var pling = new Syn([arp1,arp2,arp3],[3,5,1]); | |
//skwear | |
var skw = Osc('saw',2); | |
export function dsp(t) { | |
clock(t); | |
var beat = Math.floor(t/(60/bpm))%336; | |
var noise = Noise(); | |
//ending | |
var end_muter = beat >= 256? 0:1; | |
//wibble wobble | |
var wob_on = (beat >= 16 && beat < 320)? 1 : 0; | |
var wob_vol = 1; | |
fil.set_q(0.13 + sin(0.5)*0.13); | |
fil.set_fc(0.29 + tri(sequence(1/4,wob_lfo))*0.289); | |
if(beat > 95) { | |
wob_state=[1]; | |
wob_note = wob_note_drop; | |
wob_vol = 0.75; | |
wobble.setOcts([-1,3,2]); | |
} else { // else clause prevent variables being sticky if you want to play it again | |
wob_state = wob_state_init; | |
wob_note = wob_note_init; | |
wob_vol = 1; | |
wobble.setOcts([-1,0,-1]); | |
} | |
var wob = fil.run(wobble.mix( sequence(1/4,wob_note) )) * sequence(1/16,wob_state) * wob_on; | |
//spacey plingplongs | |
var plings = pling.mix( sequence(1/16, pling_note )) * sqr(ms2freq(16)); | |
//4-8/16-skwr | |
var fr8 = skw.play(sequence(1/2, fr8_note), (2 + Math.floor(beat/16)%2)) * sequence(1/8,fr8_on); | |
fr8 = (fr8 > 0.85)? 1:0; | |
//all le drums | |
var drums_on = (beat >= 80 && beat < 96)? 0:1; | |
var drums = arp(1/16,60,40,20) * sequence(1/16,kick_patt) + arp(1/16,60,80,3) * noise * sequence(1/16,snare_patt); | |
var drums_build = arp(1/16,60,40 + (beat - 80)*2,20) * sequence(1/16,build_kick) * ( 1 - drums_on); | |
var hats_on = beat >= 32? 1: 0; | |
var hat = arp(1/16, hat_osc.play(hat_note) + noise * 1.4, 18, 70) * sequence(1/16,hat_patt) * hats_on; | |
return ( | |
wob * wob_vol | |
+ drums * 0.9 * drums_on | |
+ drums_build * 0.9 | |
+ hat * 0.7 * drums_on * end_muter | |
+ plings * 0.09 * end_muter | |
+ fr8 * 0.2 * drums_on* end_muter | |
); | |
} |
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Done! Won't be extended. 336 beats loop!