Add wavetable oscillator with scanning, warps, and detune

packages/superdough/wavetable.mjs

@@ -0,0 +1,253 @@
+import { getAudioContext, registerSound } from './index.mjs';
+import { clamp, getSoundIndex, valueToMidi } from './util.mjs';
+import {
+  destroyAudioWorkletNode,
+  getADSRValues,
+  getFrequencyFromValue,
+  getParamADSR,
+  getPitchEnvelope,
+  getVibratoOscillator,
+  getWorklet,
+  webAudioTimeout,
+} from './helpers.mjs';
+import { logger } from './logger.mjs';
+
+const WT_MAX_MIP_LEVELS = 6;
+export const WarpMode = Object.freeze({
+  NONE: 0,
+  ASYM: 1,
+  MIRROR: 2,
+  BENDP: 3,
+  BENDM: 4,
+  BENDMP: 5,
+  SYNC: 6,
+  QUANT: 7,
+  FOLD: 8,
+  PWM: 9,
+  ORBIT: 10,
+  SPIN: 11,
+  CHAOS: 12,
+  PRIMES: 13,
+  BINARY: 14,
+  BROWNIAN: 15,
+  RECIPROCAL: 16,
+  WORMHOLE: 17,
+  LOGISTIC: 18,
+  SIGMOID: 19,
+  FRACTAL: 20,
+  FLIP: 21,
+});
+
+async function loadWavetableFrames(url, label, frameLen = 256) {
+  const ac = getAudioContext();
+  const buf = await loadBuffer(url, ac, label);
+  const ch0 = buf.getChannelData(0);
+  const total = ch0.length;
+  const numFrames = Math.floor(total / frameLen);
+  const frames = new Array(numFrames);
+  for (let i = 0; i < numFrames; i++) {
+    const start = i * frameLen;
+    frames[i] = ch0.subarray(start, start + frameLen);
+  }
+
+  // build mipmaps
+  const mipmaps = [frames];
+  let levelFrames = frames;
+  for (let level = 1; level < WT_MAX_MIP_LEVELS; level++) {
+    const prevLen = levelFrames[0].length;
+    if (prevLen <= 32) break;
+    const nextLen = prevLen >> 1;
+    const next = levelFrames.map((src) => {
+      const out = new Float32Array(nextLen);
+      for (let j = 0; j < nextLen; j++) {
+        out[j] = (src[2 * j] + src[2 * j + 1]) / 2;
+      }
+      return out;
+    });
+    mipmaps.push(next);
+    levelFrames = next;
+  }
+  return { frames, mipmaps, frameLen, numFrames };
+}
+
+const loadCache = {};
+
+function humanFileSize(bytes, si) {
+  var thresh = si ? 1000 : 1024;
+  if (bytes < thresh) return bytes + ' B';
+  var units = si
+    ? ['kB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB']
+    : ['KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB'];
+  var u = -1;
+  do {
+    bytes /= thresh;
+    ++u;
+  } while (bytes >= thresh);
+  return bytes.toFixed(1) + ' ' + units[u];
+}
+
+export function getTableInfo(hapValue, bank) {
+  const { wt, n = 0 } = hapValue;
+  let midi = valueToMidi(hapValue, 36);
+  let transpose = midi - 36; // C3 is middle C;
+  const index = getSoundIndex(n, bank.length);
+  const tableUrl = bank[index];
+  const label = `${wt}:${index}`;
+  return { transpose, tableUrl, index, midi, label };
+}
+
+const loadBuffer = (url, ac, wt, n = 0) => {
+  const label = wt ? `table "${wt}:${n}"` : 'table';
+  url = url.replace('#', '%23');
+  if (!loadCache[url]) {
+    logger(`[wavetable] load ${label}..`, 'load-table', { url });
+    const timestamp = Date.now();
+    loadCache[url] = fetch(url)
+      .then((res) => res.arrayBuffer())
+      .then(async (res) => {
+        const took = Date.now() - timestamp;
+        const size = humanFileSize(res.byteLength);
+        logger(`[wavetable] load ${label}... done! loaded ${size} in ${took}ms`, 'loaded-table', { url });
+        const decoded = await ac.decodeAudioData(res);
+        return decoded;
+      });
+  }
+  return loadCache[url];
+};
+
+function githubPath(base, subpath = '') {
+  if (!base.startsWith('github:')) {
+    throw new Error('expected "github:" at the start of pseudoUrl');
+  }
+  let [_, path] = base.split('github:');
+  path = path.endsWith('/') ? path.slice(0, -1) : path;
+  if (path.split('/').length === 2) {
+    // assume main as default branch if none set
+    path += '/main';
+  }
+  return `https://raw.githubusercontent.com/${path}/${subpath}`;
+}
+
+const _processTables = (json, baseUrl, frameLen) => {
+  return Object.entries(json).forEach(([key, value]) => {
+    if (typeof value === 'string') {
+      value = [value];
+    }
+    if (typeof value !== 'object') {
+      throw new Error('wrong json format for ' + key);
+    }
+    baseUrl = value._base || baseUrl;
+    if (baseUrl.startsWith('github:')) {
+      baseUrl = githubPath(baseUrl, '');
+    }
+    value = value.map((v) => baseUrl + v);
+    registerSound(key, (t, hapValue, onended) => onTriggerSynth(t, hapValue, onended, value, frameLen), {
+      type: 'wavetable',
+      tables: value,
+      baseUrl,
+      frameLen,
+    });
+  });
+};
+
+/**
+ * Loads a collection of wavetables to use with `wt`
+ *
+ * @name tables
+ */
+export const tables = async (url, frameLen, json) => {
+  if (json !== undefined) return _processTables(json, url, frameLen);
+  if (url.startsWith('github:')) {
+    url = githubPath(url, 'strudel.json');
+  }
+  if (url.startsWith('local:')) {
+    url = `http://localhost:5432`;
+  }
+  if (typeof fetch !== 'function') {
+    // not a browser
+    return;
+  }
+  const base = url.split('/').slice(0, -1).join('/');
+  if (typeof fetch === 'undefined') {
+    // skip fetch when in node / testing
+    return;
+  }
+  return fetch(url)
+    .then((res) => res.json())
+    .then((json) => _processTables(json, url, frameLen))
+    .catch((error) => {
+      console.error(error);
+      throw new Error(`error loading "${url}"`);
+    });
+};
+
+async function onTriggerSynth(t, value, onended, bank, frameLen) {
+  let { s, n = 0, duration } = value;
+  const ac = getAudioContext();
+  let [attack, decay, sustain, release] = getADSRValues([value.attack, value.decay, value.sustain, value.release]);
+  let sourceDesc, holdEnd, envEnd;
+  let { unison = 5, spread = 0.6, detune, wtPos, wtWarp, wtWarpMode } = value;
+  if (typeof wtWarpMode === 'string') {
+    wtWarpMode = WarpMode[wtWarpMode.toUpperCase()] ?? WarpMode.NONE;
+  }
+  detune = detune ?? 0.18;
+  const frequency = getFrequencyFromValue(value);
+  const voices = clamp(unison, 1, 100);
+  let { tableUrl, label } = getTableInfo(value, bank);
+  const payload = await loadWavetableFrames(tableUrl, label, frameLen);
+  holdEnd = t + duration;
+  envEnd = holdEnd + release + 0.01;
+  const worklet = getWorklet(
+    ac,
+    'wavetable-oscillator-processor',
+    {
+      begin: t,
+      end: envEnd,
+      frequency,
+      detune,
+      position: wtPos,
+      warp: wtWarp,
+      warpMode: wtWarpMode,
+      voices,
+      spread,
+    },
+    { outputChannelCount: [2] },
+  );
+  worklet.port.postMessage({ type: 'tables', payload });
+  sourceDesc = { source: worklet };
+  const { source } = sourceDesc;
+  if (ac.currentTime > t) {
+    logger(`[wavetable] still loading sound "${s}:${n}"`, 'highlight');
+    return;
+  }
+  if (!source) {
+    logger(`[wavetable] could not load "${s}:${n}"`, 'error');
+    return;
+  }
+  let vibratoOscillator = getVibratoOscillator(source.detune, value, t);
+  const envGain = ac.createGain();
+  const node = source.connect(envGain);
+  getParamADSR(node.gain, attack, decay, sustain, release, 0, 1, t, holdEnd, 'linear');
+  getPitchEnvelope(source.detune, value, t, holdEnd);
+
+  const out = ac.createGain(); // we need a separate gain for the cutgroups because firefox...
+  node.connect(out);
+  let handle = { node: out, bufferSource: source };
+  let timeoutNode = webAudioTimeout(
+    ac,
+    () => {
+      source.disconnect();
+      destroyAudioWorkletNode(source);
+      vibratoOscillator?.stop();
+      node.disconnect();
+      out.disconnect();
+      onended();
+    },
+    t,
+    envEnd,
+  );
+  handle.stop = (time) => {
+    timeoutNode.stop(time);
+  };
+  return handle;
+}