update webaudio to main branch

packages/webaudio/webaudio.mjs

@@ -7,15 +7,19 @@ This program is free software: you can redistribute it and/or modify it under th
 import * as strudel from '@strudel/core';
 import {
   superdough,
-  setDefaultAudioContext,
   getAudioContext,
   setLogger,
   doughTrigger,
   registerWorklet,
+  setAudioContext,
+  initAudio,
+  setSuperdoughAudioController,
+  resetGlobalEffects,
+  errorLogger,
 } from 'superdough';
 import './supradough.mjs';
 import { workletUrl } from 'supradough';
-
+import { SuperdoughAudioController } from 'superdough/superdoughoutput.mjs';
 registerWorklet(workletUrl);
 
 const { Pattern, logger, repl } = strudel;
@@ -33,12 +37,76 @@ export const webaudioOutput = (hap, _deadline, hapDuration, cps, t) => {
   return superdough(hap2value(hap), t, hapDuration, cps, hap.whole?.begin.valueOf());
 };
 
-export function webaudioRepl(options = {}) {
-  if (options.existingAudioCtx) {
-    setDefaultAudioContext(options.existingAudioCtx);
+export async function renderPatternAudio(
+  pattern,
+  cps,
+  begin,
+  end,
+  sampleRate,
+  maxPolyphony,
+  multiChannelOrbits,
+  downloadName = undefined,
+) {
+  let audioContext = getAudioContext();
+  await audioContext.close();
+  audioContext = new OfflineAudioContext(2, ((end - begin) / cps) * sampleRate, sampleRate);
+  setAudioContext(audioContext);
+  setSuperdoughAudioController(new SuperdoughAudioController(audioContext));
+  await initAudio({
+    maxPolyphony,
+    multiChannelOrbits,
+  });
+  logger('[webaudio] preloading');
+
+  // Calling superdough(...) in ascending onset time order is important
+  // for controls that depend on the audio graph state like `cut`
+  let haps = pattern
+    .queryArc(begin, end, { _cps: cps })
+    .sort((a, b) => a.whole.begin.valueOf() - b.whole.begin.valueOf());
+  for (const hap of haps) {
+    if (hap.hasOnset()) {
+      try {
+        await superdough(
+          hap2value(hap),
+          (hap.whole.begin.valueOf() - begin) / cps,
+          hap.duration / cps,
+          cps,
+          (hap.whole?.begin.valueOf() - begin) / cps,
+        );
+      } catch (err) {
+        errorLogger(err, 'webaudio');
+      }
+    }
   }
+  logger('[webaudio] start rendering');
+
+  return audioContext
+    .startRendering()
+    .then((renderedBuffer) => {
+      const wavBuffer = audioBufferToWav(renderedBuffer);
+      const blob = new Blob([wavBuffer], { type: 'audio/wav' });
+      const url = URL.createObjectURL(blob);
+      const a = document.createElement('a');
+      a.href = url;
+      downloadName = downloadName ? `${downloadName}.wav` : `${new Date().toISOString()}.wav`;
+      a.download = `${downloadName}`;
+      document.body.appendChild(a);
+      a.click();
+      document.body.removeChild(a);
+      URL.revokeObjectURL(url);
+    })
+    .finally(async () => {
+      setAudioContext(null);
+      setSuperdoughAudioController(null);
+      resetGlobalEffects();
+    });
+}
+
+export function webaudioRepl(options = {}) {
+  const audioContext = options.audioContext ?? getAudioContext();
+  setAudioContext(audioContext);
   options = {
-    getTime: () => getAudioContext().currentTime,
+    getTime: () => audioContext.currentTime,
     defaultOutput: webaudioOutput,
     ...options,
   };
@@ -48,3 +116,98 @@ export function webaudioRepl(options = {}) {
 Pattern.prototype.dough = function () {
   return this.onTrigger(doughTrigger, 1);
 };
+
+function audioBufferToWav(buffer, opt) {
+  opt = opt || {};
+
+  var numChannels = buffer.numberOfChannels;
+  var sampleRate = buffer.sampleRate;
+  var format = opt.float32 ? 3 : 1;
+  var bitDepth = format === 3 ? 32 : 16;
+
+  var result;
+  if (numChannels === 2) {
+    result = interleave(buffer.getChannelData(0), buffer.getChannelData(1));
+  } else {
+    result = buffer.getChannelData(0);
+  }
+
+  return encodeWAV(result, format, sampleRate, numChannels, bitDepth);
+}
+
+function encodeWAV(samples, format, sampleRate, numChannels, bitDepth) {
+  var bytesPerSample = bitDepth / 8;
+  var blockAlign = numChannels * bytesPerSample;
+
+  var buffer = new ArrayBuffer(44 + samples.length * bytesPerSample);
+  var view = new DataView(buffer);
+
+  /* RIFF identifier */
+  writeString(view, 0, 'RIFF');
+  /* RIFF chunk length */
+  view.setUint32(4, 36 + samples.length * bytesPerSample, true);
+  /* RIFF type */
+  writeString(view, 8, 'WAVE');
+  /* format chunk identifier */
+  writeString(view, 12, 'fmt ');
+  /* format chunk length */
+  view.setUint32(16, 16, true);
+  /* sample format (raw) */
+  view.setUint16(20, format, true);
+  /* channel count */
+  view.setUint16(22, numChannels, true);
+  /* sample rate */
+  view.setUint32(24, sampleRate, true);
+  /* byte rate (sample rate * block align) */
+  view.setUint32(28, sampleRate * blockAlign, true);
+  /* block align (channel count * bytes per sample) */
+  view.setUint16(32, blockAlign, true);
+  /* bits per sample */
+  view.setUint16(34, bitDepth, true);
+  /* data chunk identifier */
+  writeString(view, 36, 'data');
+  /* data chunk length */
+  view.setUint32(40, samples.length * bytesPerSample, true);
+  if (format === 1) {
+    // Raw PCM
+    floatTo16BitPCM(view, 44, samples);
+  } else {
+    writeFloat32(view, 44, samples);
+  }
+
+  return buffer;
+}
+
+function interleave(inputL, inputR) {
+  var length = inputL.length + inputR.length;
+  var result = new Float32Array(length);
+
+  var index = 0;
+  var inputIndex = 0;
+
+  while (index < length) {
+    result[index++] = inputL[inputIndex];
+    result[index++] = inputR[inputIndex];
+    inputIndex++;
+  }
+  return result;
+}
+
+function writeFloat32(output, offset, input) {
+  for (var i = 0; i < input.length; i++, offset += 4) {
+    output.setFloat32(offset, input[i], true);
+  }
+}
+
+function floatTo16BitPCM(output, offset, input) {
+  for (var i = 0; i < input.length; i++, offset += 2) {
+    var s = Math.max(-1, Math.min(1, input[i]));
+    output.setInt16(offset, s < 0 ? s * 0x8000 : s * 0x7fff, true);
+  }
+}
+
+function writeString(view, offset, string) {
+  for (var i = 0; i < string.length; i++) {
+    view.setUint8(offset + i, string.charCodeAt(i));
+  }
+}