1 files changed, 88 insertions, 0 deletions
diff --git a/sample_editor/processor.js b/sample_editor/processor.js
new file mode 100644
index 0000000..67d77ba
--- /dev/null
+++ b/sample_editor/processor.js
@@ -0,0 +1,88 @@
+class CustomProcessor extends AudioWorkletProcessor {
+    static get parameterDescriptors() {
+        return [
+            { name: 'gain', defaultValue: 1.0, minValue: 0.0, maxValue: 2000.0 },
+            // Add parameters for the 8 biquad filters here
+            ...Array.from({ length: 8 }, (_, index) => [
+                { name: `b0_${index}`, defaultValue: 1.0 },
+                { name: `b1_${index}`, defaultValue: 0.0 },
+                { name: `b2_${index}`, defaultValue: 0.0 },
+                { name: `a1_${index}`, defaultValue: 0.0 },
+                { name: `a2_${index}`, defaultValue: 0.0 }
+            ]).flat()
+        ];
+    }
+
+    constructor() {
+        super();
+        this.sampleRate = sampleRate; // `sampleRate` is available globally here
+        console.log('Sample rate:', this.sampleRate);
+        // Set up state variables for the 8 biquad filters, initialize to 0
+        this.biquadState = Array.from({ length: 8 }, () => ({ state1: 0.0, state2: 0.0 }));
+        this.volumeEnvelope = [];
+        this.wavetablemode = false;
+        this.envelopeIndex = 0;
+        this.currentSample = 0;
+        this.port.onmessage = (event) => {
+            if (event.data.type === 'volumeEnvelope') {
+                this.volumeEnvelope = event.data.envelope;
+                this.dx = event.data.dx;
+                this.envelopeIndex = 0;
+                this.currentSample = 0;
+                this.wavetablemode = event.data.wavetablemode;
+
+            }
+        };
+    }
+
+    process(inputs, outputs, parameters) {
+        const input = inputs[0];
+        const output = outputs[0];
+        const gainParam = parameters.gain;
+        const pregain = gainParam[0];
+        for (let channel = 0; channel < input.length; channel++) {
+            const inputChannel = input[channel];
+            const outputChannel = output[channel];
+            let cs = this.currentSample;
+            let dx = this.dx;
+            for (let i = 0; i < inputChannel.length; i++, cs++) {
+                let currentSample = inputChannel[i];
+
+                // Run through 8 biquad filters in series
+                if (1) for (let biquadIndex = 0; biquadIndex < 8; biquadIndex++) {
+                    const b0 = parameters[`b0_${biquadIndex}`][0];
+                    const b1 = parameters[`b1_${biquadIndex}`][0];
+                    const b2 = parameters[`b2_${biquadIndex}`][0];
+                    const a1 = parameters[`a1_${biquadIndex}`][0];
+                    const a2 = parameters[`a2_${biquadIndex}`][0];
+                    const state = this.biquadState[biquadIndex];
+                    // Apply Direct Form II Transposed structure
+                    const output = currentSample * b0 + state.state1;
+                    state.state1 = currentSample * b1 - a1 * output + state.state2;
+                    state.state2 = currentSample * b2 - a2 * output;
+                    currentSample = output;
+                }
+                let postgain = 1.0;
+                if (this.volumeEnvelope.length > 0) {
+                    let x = cs * dx;
+                    if (this.wavetablemode) x=x%1;
+                    while (this.envelopeIndex < this.volumeEnvelope.length - 2 && x >= this.volumeEnvelope[this.envelopeIndex + 1].x)
+                        this.envelopeIndex++;
+                    while (this.envelopeIndex > 0 && x < this.volumeEnvelope[this.envelopeIndex].x)
+                        this.envelopeIndex--;
+                    const p1 = this.volumeEnvelope[this.envelopeIndex];
+                    const p2 = this.volumeEnvelope[this.envelopeIndex + 1];
+                    const t = Math.min(1, (x - p1.x) / (p2.x - p1.x));
+                    postgain = p1.y + (p2.y - p1.y) * Math.pow(t, p1.power);
+                    //if (cs < 16) postgain *= cs / 16;
+                }
+                outputChannel[i] = /*Math.tanh*/(currentSample * pregain) * postgain;
+            }
+        }
+        if (input.length > 0)
+            this.currentSample += input[0].length;
+        return true;
+    }
+}
+
+registerProcessor('custom-processor', CustomProcessor);