Merge pull request 'Optimize wavetable synth' (#1613) from glossing/strudel:glossing/wavetable-optimizations into main

Reviewed-on: https://codeberg.org/uzu/strudel/pulls/1613

packages/superdough/wavetable.mjs

@@ -5,7 +5,6 @@ import {
   destroyAudioWorkletNode,
   getADSRValues,
   getFrequencyFromValue,
-  getLfo,
   getParamADSR,
   getPitchEnvelope,
   getVibratoOscillator,
@@ -14,7 +13,6 @@ import {
 } from './helpers.mjs';
 import { logger } from './logger.mjs';
 
-const WT_MAX_MIP_LEVELS = 6;
 export const Warpmode = Object.freeze({
   NONE: 0,
   ASYM: 1,
@@ -40,39 +38,25 @@ export const Warpmode = Object.freeze({
   FLIP: 21,
 });
 
-async function loadWavetableFrames(url, label, frameLen = 2048) {
-  const buf = await loadBuffer(url, label);
-  const ch0 = buf.getChannelData(0);
-  const total = ch0.length;
-  const numFrames = Math.max(1, 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);
+const seenKeys = new Set();
+async function getPayload(url, label, frameLen = 2048) {
+  const key = `${url},${frameLen}`;
+  if (!seenKeys.has(key)) {
+    const buf = await loadBuffer(url, label);
+    const ch0 = buf.getChannelData(0);
+    const total = ch0.length;
+    const numFrames = Math.max(1, 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);
+    }
+    seenKeys.add(key);
+    return { frames, frameLen, numFrames, key };
   }
-
-  // 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 };
+  return { frameLen, key }; // worklet will use the cached version
 }
 
-const loadCache = {};
-
 function humanFileSize(bytes, si) {
   var thresh = si ? 1000 : 1024;
   if (bytes < thresh) return bytes + ' B';
@@ -117,6 +101,7 @@ async function decodeAtNativeRate(arr) {
   return await tempAC.decodeAudioData(arr);
 }
 
+const loadCache = {};
 const loadBuffer = (url, label) => {
   url = url.replace('#', '%23');
   if (!loadCache[url]) {
@@ -222,7 +207,7 @@ export const tables = async (url, frameLen, json, options = {}) => {
 };
 
 export async function onTriggerSynth(t, value, onended, tables, cps, frameLen) {
-  const { s, n = 0, duration } = value;
+  const { s, n = 0, duration, clip } = value;
   const ac = getAudioContext();
   const [attack, decay, sustain, release] = getADSRValues([value.attack, value.decay, value.sustain, value.release]);
   let { warpmode } = value;
@@ -231,8 +216,11 @@ export async function onTriggerSynth(t, value, onended, tables, cps, frameLen) {
   }
   const frequency = getFrequencyFromValue(value);
   const { url, label } = getCommonSampleInfo(value, tables);
-  const payload = await loadWavetableFrames(url, label, frameLen);
-  const holdEnd = t + duration;
+  const payload = await getPayload(url, label, frameLen);
+  let holdEnd = t + duration;
+  if (clip !== undefined) {
+    holdEnd = Math.min(t + clip * duration, holdEnd);
+  }
   const endWithRelease = holdEnd + release;
   const envEnd = endWithRelease + 0.01;
   const source = getWorklet(
@@ -252,7 +240,7 @@ export async function onTriggerSynth(t, value, onended, tables, cps, frameLen) {
     },
     { outputChannelCount: [2] },
   );
-  source.port.postMessage({ type: 'tables', payload });
+  source.port.postMessage({ type: 'table', payload });
   if (ac.currentTime > t) {
     logger(`[wavetable] still loading sound "${s}:${n}"`, 'highlight');
     return;
@@ -322,13 +310,12 @@ export async function onTriggerSynth(t, value, onended, tables, cps, frameLen) {
   const vibratoOscillator = getVibratoOscillator(source.parameters.get('detune'), value, t);
   const envGain = ac.createGain();
   const node = source.connect(envGain);
-  getParamADSR(node.gain, attack, decay, sustain, release, 0, 1, t, holdEnd, 'linear');
+  getParamADSR(node.gain, attack, decay, sustain, release, 0, 0.3, t, holdEnd, 'linear');
   getPitchEnvelope(source.parameters.get('detune'), value, t, holdEnd);
   const handle = { node, source };
   const timeoutNode = webAudioTimeout(
     ac,
     () => {
-      source.disconnect();
       destroyAudioWorkletNode(source);
       vibratoOscillator?.stop();
       node.disconnect();

packages/superdough/worklets.mjs

@@ -137,7 +137,7 @@ class LFOProcessor extends AudioWorkletProcessor {
     }
   }
 
-  process(inputs, outputs, parameters) {
+  process(_inputs, outputs, parameters) {
     const begin = parameters['begin'][0];
     if (currentTime >= parameters.end[0]) {
       return false;
@@ -510,7 +510,7 @@ class SuperSawOscillatorProcessor extends AudioWorkletProcessor {
       },
     ];
   }
-  process(input, outputs, params) {
+  process(_input, outputs, params) {
     if (currentTime <= params.begin[0]) {
       return true;
     }
@@ -1043,6 +1043,7 @@ function brownian(x, oct = 4) {
   return (sum / norm) * 2 - 1;
 }
 
+const tablesCache = {};
 class WavetableOscillatorProcessor extends AudioWorkletProcessor {
   static get parameterDescriptors() {
     return [
@@ -1061,31 +1062,40 @@ class WavetableOscillatorProcessor extends AudioWorkletProcessor {
 
   constructor(options) {
     super(options);
-    this.tables = null;
     this.frameLen = 0;
     this.numFrames = 0;
     this.phase = [];
-    this.syncRatio = 1;
+    this.invSR = 1 / sampleRate;
 
     this.port.onmessage = (e) => {
       const { type, payload } = e.data || {};
-      if (type === 'tables') {
-        this.tables = payload.mipmaps;
+      if (type === 'table') {
+        const key = payload.key;
         this.frameLen = payload.frameLen;
+        if (!tablesCache[key]) {
+          const tables = [payload.frames];
+          let table = tables[0];
+          for (let level = 1; level < 1; level++) {
+            const nextLen = table.length >> 1;
+            const nextTable = table.map((frame) => {
+              const avg = new Float32Array(nextLen);
+              for (let i = 0; i < nextLen; i++) {
+                avg[i] = (frame[2 * i] + frame[2 * i + 1]) / 2;
+              }
+              return avg;
+            });
+            tables.push(nextTable);
+            table = nextTable;
+            if (nextLen <= 32) break;
+          }
+          tablesCache[key] = tables;
+        }
+        this.tables = tablesCache[key];
         this.numFrames = this.tables[0].length;
       }
     };
   }
 
-  _chooseMip(dphi) {
-    const approxHarm = Math.min(64, 1 / Math.max(1e-6, dphi));
-    let level = 0;
-    while (level + 1 < (this.tables?.length || 1) && approxHarm < this.tables[level][0].length / 8) {
-      level++;
-    }
-    return level;
-  }
-
   _mirror(x) {
     return 1 - Math.abs(2 * x - 1);
   }
@@ -1222,14 +1232,25 @@ class WavetableOscillatorProcessor extends AudioWorkletProcessor {
   }
 
   _sampleFrame(frame, phase) {
-    const pos = phase * frame.length;
+    const len = frame.length;
+    const pos = phase * len;
     const i = pos | 0;
     const frac = pos - i;
-    const a = frame[i % frame.length];
-    const b = frame[(i + 1) % frame.length];
+    const a = frame[i];
+    const i1 = i + 1 < len ? i + 1 : 0; // fast wrap
+    const b = frame[i1];
     return a + (b - a) * frac;
   }
 
+  _chooseMip(dphi) {
+    const approxHarm = clamp(dphi, 1e-6, 64);
+    let level = 0;
+    while (level + 1 < (this.tables?.length || 1) && approxHarm < this.tables[level][0].length / 8) {
+      level++;
+    }
+    return level;
+  }
+
   process(_inputs, outputs, parameters) {
     if (currentTime >= parameters.end[0]) {
       return false;
@@ -1239,29 +1260,27 @@ class WavetableOscillatorProcessor extends AudioWorkletProcessor {
     }
     const outL = outputs[0][0];
     const outR = outputs[0][1] || outputs[0][0];
-
     if (!this.tables) {
       outL.fill(0);
       if (outR !== outL) outR.set(outL);
       return true;
     }
-
     for (let i = 0; i < outL.length; i++) {
       const detune = pv(parameters.detune, i);
-      const tablePos = pv(parameters.position, i);
+      const tablePos = clamp(pv(parameters.position, i), 0, 1);
       const idx = tablePos * (this.numFrames - 1);
       const fIdx = idx | 0;
       const frac = idx - fIdx;
-      const warpAmount = pv(parameters.warp, i);
+      const warpAmount = clamp(pv(parameters.warp, i), 0, 1);
       const warpMode = pv(parameters.warpMode, i);
       const voices = pv(parameters.voices, i);
-      const phaseRand = pv(parameters.phaserand, i);
-      const spread = voices > 1 ? pv(parameters.spread, i) : 0;
+      const phaseRand = clamp(pv(parameters.phaserand, i), 0, 1);
+      const spread = voices > 1 ? clamp(pv(parameters.spread, i), 0, 1) : 0;
       const gain1 = Math.sqrt(0.5 - 0.5 * spread);
       const gain2 = Math.sqrt(0.5 + 0.5 * spread);
       let f = pv(parameters.frequency, i);
       f = applySemitoneDetuneToFrequency(f, detune / 100); // overall detune
-      const normalizer = 0.3 / Math.sqrt(voices);
+      const normalizer = 1 / Math.sqrt(voices);
       for (let n = 0; n < voices; n++) {
         const isOdd = (n & 1) == 1;
         let gainL = gain1;
@@ -1272,7 +1291,7 @@ class WavetableOscillatorProcessor extends AudioWorkletProcessor {
           gainR = gain1;
         }
         const fVoice = applySemitoneDetuneToFrequency(f, getUnisonDetune(voices, detune, n)); // voice detune
-        const dPhase = fVoice / sampleRate;
+        const dPhase = fVoice * this.invSR;
         const level = this._chooseMip(dPhase);
         const table = this.tables[level];