Fixing more bugs

public/worklets/fold-crush-processor.js

@@ -0,0 +1,109 @@
+class FoldCrushProcessor extends AudioWorkletProcessor {
+  constructor() {
+    super()
+
+    this.clipMode = 'wrap'
+    this.drive = 1
+    this.bitDepth = 16
+    this.crushAmount = 0
+    this.bitcrushPhase = 0
+    this.lastCrushedValue = 0
+
+    this.port.onmessage = (event) => {
+      const { type, value } = event.data
+      switch (type) {
+        case 'clipMode':
+          this.clipMode = value
+          break
+        case 'drive':
+          this.drive = value
+          break
+        case 'bitDepth':
+          this.bitDepth = value
+          break
+        case 'crushAmount':
+          this.crushAmount = value
+          break
+      }
+    }
+  }
+
+  wrap(sample) {
+    const range = 2.0
+    let wrapped = sample
+    while (wrapped > 1.0) wrapped -= range
+    while (wrapped < -1.0) wrapped += range
+    return wrapped
+  }
+
+  clamp(sample) {
+    return Math.max(-1.0, Math.min(1.0, sample))
+  }
+
+  fold(sample) {
+    let folded = sample
+    while (folded > 1.0 || folded < -1.0) {
+      if (folded > 1.0) {
+        folded = 2.0 - folded
+      }
+      if (folded < -1.0) {
+        folded = -2.0 - folded
+      }
+    }
+    return folded
+  }
+
+  processWavefolder(sample) {
+    switch (this.clipMode) {
+      case 'wrap':
+        return this.wrap(sample)
+      case 'clamp':
+        return this.clamp(sample)
+      case 'fold':
+        return this.fold(sample)
+      default:
+        return sample
+    }
+  }
+
+  processBitcrush(sample) {
+    if (this.crushAmount === 0 && this.bitDepth === 16) {
+      return sample
+    }
+
+    const step = Math.pow(0.5, this.bitDepth)
+    const phaseIncrement = 1 - (this.crushAmount / 100)
+
+    this.bitcrushPhase += phaseIncrement
+
+    if (this.bitcrushPhase >= 1.0) {
+      this.bitcrushPhase -= 1.0
+      const crushed = Math.floor(sample / step + 0.5) * step
+      this.lastCrushedValue = Math.max(-1, Math.min(1, crushed))
+      return this.lastCrushedValue
+    } else {
+      return this.lastCrushedValue
+    }
+  }
+
+  process(inputs, outputs) {
+    const input = inputs[0]
+    const output = outputs[0]
+
+    if (input.length > 0 && output.length > 0) {
+      const inputChannel = input[0]
+      const outputChannel = output[0]
+
+      for (let i = 0; i < inputChannel.length; i++) {
+        const driven = inputChannel[i] * this.drive
+        let processed = this.processWavefolder(driven)
+        processed = this.processBitcrush(processed)
+        outputChannel[i] = processed
+      }
+    }
+
+    return true
+  }
+}
+
+registerProcessor('fold-crush-processor', FoldCrushProcessor)