wip

packages/superdough/worklets.mjs

@@ -11,6 +11,9 @@ const PI = Math.PI;
 const TWO_PI = 2 * PI;
 const INVSR = 1 / sampleRate;
 
+const timeToCoeff = (t) => 1 - Math.exp(-INVSR / t);
+const dbToLin = (db) => Math.pow(10, db / 20);
+
 const clamp = (num, min, max) => Math.min(Math.max(num, min), max);
 const mod = (n, m) => ((n % m) + m) % m;
 const lerp = (a, b, n) => n * (b - a) + a;
@@ -121,8 +124,8 @@ class LFOProcessor extends AudioWorkletProcessor {
       { name: 'shape', defaultValue: 0 },
       { name: 'curve', defaultValue: 1 },
       { name: 'dcoffset', defaultValue: 0 },
-      { name: 'min', defaultValue: 0 },
-      { name: 'max', defaultValue: 1 },
+      { name: 'min', defaultValue: -1e9 },
+      { name: 'max', defaultValue: 1e9 },
     ];
   }
 
@@ -140,7 +143,8 @@ class LFOProcessor extends AudioWorkletProcessor {
 
   process(_inputs, outputs, parameters) {
     const begin = parameters['begin'][0];
-    if (currentTime >= parameters.end[0]) {
+    const end = parameters['end'][0];
+    if (currentTime >= end) {
       return false;
     }
     if (currentTime <= begin) {
@@ -158,6 +162,7 @@ class LFOProcessor extends AudioWorkletProcessor {
     const curve = parameters['curve'][0];
 
     const dcoffset = parameters['dcoffset'][0];
+
     const min = parameters['min'][0];
     const max = parameters['max'][0];
     const shape = waveShapeNames[parameters['shape'][0]];
@@ -978,7 +983,9 @@ class EnvelopeProcessor extends AudioWorkletProcessor {
       { name: 'attackCurve', defaultValue: 0, minValue: -1, maxValue: 1 },
       { name: 'decayCurve', defaultValue: 0, minValue: -1, maxValue: 1 },
       { name: 'releaseCurve', defaultValue: 0, minValue: -1, maxValue: 1 },
-      { name: 'peak', defaultValue: 1 },
+      { name: 'depth', defaultValue: 1 },
+      { name: 'min', defaultValue: -1e9 },
+      { name: 'max', defaultValue: 1e9 },
       { name: 'retrigger', defaultValue: 1, minValue: 0, maxValue: 1 },
     ];
   }
@@ -1020,9 +1027,15 @@ class EnvelopeProcessor extends AudioWorkletProcessor {
   }
 
   process(_inputs, outputs, params) {
+    const begin = params['begin'][0];
+    const end = params['end'][0];
+    if (currentTime >= end) {
+      return false;
+    }
+    if (currentTime <= begin) {
+      return true;
+    }
     const out = outputs[0][0];
-    if (!out) return true;
-    const begin = pv(params.begin, 0);
     const retrigger = pv(params.retrigger, 0) >= 0.5; // convert to bool
     if (begin !== this.beginTime && (this.state === 0 || retrigger)) {
       // triggered
@@ -1040,7 +1053,9 @@ class EnvelopeProcessor extends AudioWorkletProcessor {
       const aCurve = pv(params.attackCurve, i);
       const dCurve = pv(params.decayCurve, i);
       const rCurve = pv(params.releaseCurve, i);
-      const peak = pv(params.peak, i);
+      const depth = pv(params.depth, i);
+      const min = pv(params.min, i);
+      const max = pv(params.max, i);
       const states = [
         { time: Number.POSITIVE_INFINITY, start: 0, target: 0 }, // idle
         { time: attack, start: this.attackStart, target: 1, curve: aCurve },
@@ -1054,7 +1069,7 @@ class EnvelopeProcessor extends AudioWorkletProcessor {
         this.state = (this.state + 1) % states.length;
         time = states[this.state].time;
       }
-      out[i] = this.val * peak;
+      out[i] = clamp(this.val * depth, min, max);
     }
     return true;
   }
@@ -1385,3 +1400,82 @@ class WavetableOscillatorProcessor extends AudioWorkletProcessor {
 }
 
 registerProcessor('wavetable-oscillator-processor', WavetableOscillatorProcessor);
+
+class TransientProcessor extends AudioWorkletProcessor {
+  static get parameterDescriptors() {
+    return [];
+  }
+
+  constructor(options) {
+    super();
+    this.gainCoeff = timeToCoeff(0.2);
+    this.avgGain = 1;
+    let {
+      attackTime = 0.003,
+      sustainTime = 0.08,
+      attack = 0,
+      sustain = 0,
+      sensitivity = 0.1,
+      mix = 1,
+      begin = 0,
+      end = 0,
+    } = options.processorOptions;
+    attackTime = clamp(attackTime, 0.0005, 0.05);
+    sustainTime = clamp(sustainTime, 0.01, 0.5);
+    this.attackCoeff = timeToCoeff(attackTime);
+    this.sustainCoeff = timeToCoeff(sustainTime);
+    this.attackAmt = clamp(attack, -1, 1);
+    this.sustainAmt = clamp(sustain, -1, 1);
+    this.scaling = 0.5 + 5 * clamp(sensitivity, 0, 1);
+    this.mix = clamp(mix, 0, 1);
+    this.begin = begin;
+    this.end = end;
+    this.attackEnv = new Float32Array(2); // assume stereo
+    this.sustainEnv = new Float32Array(2);
+  }
+
+  process(inputs, outputs, _params) {
+    const input = inputs[0];
+    const output = outputs[0];
+    if (currentTime >= this.end) {
+      return false;
+    }
+    if (currentTime <= this.begin) {
+      return true;
+    }
+    const channels = input.length;
+    if (channels > this.attackEnv.length) {
+      this.attackEnv = new Float32Array(channels);
+      this.sustainEnv = new Float32Array(channels);
+    }
+    let avgGain = this.avgGain;
+    for (let ch = 0; ch < channels; ch++) {
+      let attEnv = this.attackEnv[ch];
+      let susEnv = this.sustainEnv[ch];
+      for (let n = 0; n < blockSize; n++) {
+        const sample = input[ch][n];
+        const x = Math.abs(sample);
+        attEnv = lerp(attEnv, x, this.attackCoeff);
+        susEnv = lerp(susEnv, x, this.sustainCoeff);
+        const peakiness = clamp((this.scaling * (attEnv - susEnv)) / (susEnv + 1e-6), -1.5, 1.5);
+        const attScale = peakiness > 0 ? peakiness : 0;
+        const susScale = peakiness < 0 ? -peakiness : 0;
+        const attackGain = dbToLin(this.attackAmt * attScale * 18);
+        const sustainGain = dbToLin(this.sustainAmt * susScale * 36);
+        const gain = clamp(attackGain * sustainGain, 0, 8);
+        avgGain = lerp(avgGain, gain, this.gainCoeff);
+        const makeup = avgGain > 1e-3 ? 1 / avgGain : 1;
+        const wet = sample * gain * makeup;
+        let y = lerp(sample, wet, this.mix);
+        y /= 1 + Math.abs(y); // soft clip
+        output[ch][n] = y;
+      }
+      this.attackEnv[ch] = attEnv;
+      this.sustainEnv[ch] = susEnv;
+    }
+    this.avgGain = avgGain;
+    return true;
+  }
+}
+
+registerProcessor('transient-processor', TransientProcessor);