white brown pink noise + crackle alias for dust

packages/supradough/dough.mjs

@@ -108,6 +108,51 @@ export class Dust {
   update = (density) => (Math.random() < density * ISR ? Math.random() : 0);
 }
 
+export class WhiteNoise {
+  update() {
+    return Math.random() * 2 - 1;
+  }
+}
+
+export class BrownNoise {
+  constructor() {
+    this.out = 0;
+  }
+  update() {
+    let white = Math.random() * 2 - 1;
+    this.out = (this.out + 0.02 * white) / 1.02;
+    return this.out;
+  }
+}
+
+export class PinkNoise {
+  constructor() {
+    this.b0 = 0;
+    this.b1 = 0;
+    this.b2 = 0;
+    this.b3 = 0;
+    this.b4 = 0;
+    this.b5 = 0;
+    this.b6 = 0;
+  }
+
+  update() {
+    const white = Math.random() * 2 - 1;
+
+    this.b0 = 0.99886 * this.b0 + white * 0.0555179;
+    this.b1 = 0.99332 * this.b1 + white * 0.0750759;
+    this.b2 = 0.969 * this.b2 + white * 0.153852;
+    this.b3 = 0.8665 * this.b3 + white * 0.3104856;
+    this.b4 = 0.55 * this.b4 + white * 0.5329522;
+    this.b5 = -0.7616 * this.b5 - white * 0.016898;
+
+    const pink = this.b0 + this.b1 + this.b2 + this.b3 + this.b4 + this.b5 + this.b6 + white * 0.5362;
+    this.b6 = white * 0.115926;
+
+    return pink * 0.11;
+  }
+}
+
 export class Impulse {
   phase = 1;
   update(freq) {
@@ -369,7 +414,11 @@ let oscillators = {
   pulse: PulseOsc,
   pulze: PulzeOsc,
   dust: Dust,
+  crackle: Dust,
   impulse: Impulse,
+  white: WhiteNoise,
+  brown: BrownNoise,
+  pink: PinkNoise,
 };
 
 const defaultDefaultValues = {