move core repl + add package

.gitignore

@@ -26,4 +26,5 @@ node_modules/
 .DS_Store
 repl-parcel
 mytunes.ts
-doc
+doc
+.parcel-cache

packages/webaudio/clockworker.mjs

@@ -4,17 +4,14 @@ const urlifyFunction = (func) => URL.createObjectURL(new Blob([stringifyFunction
 const createWorker = (func) => new Worker(urlifyFunction(func));
 
 // this class is basically the tale of two clocks
-class Metro {
+class ClockWorker {
   worker;
   audioContext;
-  startedAt = 0;
-  lastEnd;
-  lookahead = 0.2; // query offset
   interval = 0.2; // query span
-  constructor(audioContext, callback, interval = this.interval, lookahead = this.lookahead) {
+  lastEnd = 0;
+  constructor(audioContext, callback, interval = this.interval) {
     this.audioContext = audioContext;
     this.interval = interval;
-    this.lookahead = lookahead;
     this.worker = createWorker(() => {
       // we cannot use closures here!
       let interval;
@@ -46,25 +43,27 @@ class Metro {
       };
     });
     this.worker.postMessage({ interval });
+    // const round = (n, d) => Math.round(n * d) / d;
+    const precision = 100;
     this.worker.onmessage = (e) => {
       if (e.data === 'tick') {
-        const begin = this.lastEnd || this.startedAt + this.lookahead;
-        const end = begin + this.interval;
+        const begin = this.lastEnd || this.audioContext.currentTime;
+        const end = this.audioContext.currentTime + this.interval; // DONT reference begin here!
         this.lastEnd = end;
         // callback with query span, using clock #2 (the audio clock)
-        callback(begin, end, this.lookahead);
+        callback(begin, end);
       }
     };
   }
   start() {
+    console.log('start...');
     this.audioContext.resume();
-    delete this.lastEnd;
-    this.startedAt = this.audioContext.currentTime;
     this.worker.postMessage('start');
   }
   stop() {
+    console.log('stop...');
     this.worker.postMessage('stop');
   }
 }
 
-export default Metro;
+export default ClockWorker;

packages/webaudio/examples/repl.html

@@ -0,0 +1,62 @@
+<div style="position: absolute; top: 0; right: 0; padding: 4px">
+  <button id="start" style="margin-bottom: 4px; font-size: 2em">start</button><br />
+  <button id="stop" style="font-size: 2em">stop</button>
+</div>
+<textarea
+  style="font-size: 2em; background: #e8d565; color: #323230; height: 100%; width: 100%; outline: none; border: 0"
+  id="text"
+  spellcheck="false"
+>
+Loading...</textarea
+>
+<script type="module">
+  document.body.style = 'margin: 0';
+  import * as strudel from '@strudel.cycles/core';
+  import '@strudel.cycles/core/euclid.mjs';
+  import { Scheduler, getAudioContext } from '@strudel.cycles/webaudio';
+
+  const { cat, State, TimeSpan } = strudel;
+  Object.assign(window, strudel); // add strudel to eval scope
+
+  const audioContext = getAudioContext();
+  const interval = 0.1;
+  const lookahead = 0.5;
+  const scheduler = new Scheduler(audioContext, interval, lookahead);
+
+  let initialCode = `sequence(1,2).mul(55/2) // frequencies
+.mul(slowcat(1,2))
+.mul(slowcat(1,3/2,4/3,5/3).slow(8))
+.fast(3)
+.velocity(.5)
+.osc(cat('sawtooth','square').fast(2))
+.adsr(0.01,.02,.5,0.1)
+.filter('lowshelf',800,25)
+.out()`;
+
+  try {
+    const base64 = decodeURIComponent(window.location.href.split('#')[1]);
+    initialCode = atob(base64);
+  } catch (err) {
+    console.warn('failed to decode', err);
+  }
+  const input = document.getElementById('text');
+  input.value = initialCode;
+  const evaluate = () => {
+    try {
+      const pattern = eval(input.value);
+      console.log('value', input.value);
+
+      console.log('pattern', pattern);
+
+      scheduler.setPattern(pattern);
+      window.location.hash = '#' + encodeURIComponent(btoa(input.value)); // update url hash
+    } catch (err) {
+      console.warn(err);
+    }
+  };
+  evaluate();
+  input.addEventListener('input', () => evaluate());
+
+  document.getElementById('start').addEventListener('click', () => scheduler.start());
+  document.getElementById('stop').addEventListener('click', () => scheduler.stop());
+</script>

packages/webaudio/index.mjs

@@ -0,0 +1,3 @@
+export { default as ClockWorker } from './clockworker.mjs';
+export { default as Scheduler } from './scheduler.mjs';
+export * from './webaudio.mjs';

packages/webaudio/package.json

@@ -0,0 +1,32 @@
+{
+  "name": "@strudel.cycles/webaudio",
+  "version": "0.0.1",
+  "description": "Web Audio helpers for Strudel",
+  "main": "index.mjs",
+  "directories": {
+    "example": "examples"
+  },
+  "scripts": {
+    "example": "parcel examples/repl.html"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/tidalcycles/strudel.git"
+  },
+  "keywords": [
+    "tidalcycles",
+    "strudel",
+    "pattern",
+    "livecoding",
+    "algorave"
+  ],
+  "author": "Felix Roos <flix91@gmail.com>",
+  "license": "GPL-3.0-or-later",
+  "bugs": {
+    "url": "https://github.com/tidalcycles/strudel/issues"
+  },
+  "homepage": "https://github.com/tidalcycles/strudel#readme",
+  "devDependencies": {
+    "parcel": "^2.4.1"
+  }
+}

packages/webaudio/scheduler.mjs

@@ -1,10 +1,13 @@
+import ClockWorker from './clockworker.mjs';
+
 class Scheduler {
-  metro;
-  constructor(interval = 0.2, lookahead = 0.2) {
-    this.metro = new Metro(
+  worker;
+  pattern;
+  constructor(audioContext, interval = 0.2) {
+    this.worker = new ClockWorker(
       audioContext,
-      (begin, end, lookahead) => {
-        pattern.query(new State(new TimeSpan(begin - lookahead, end - lookahead))).forEach((e) => {
+      (begin, end) => {
+        this.pattern.query(new State(new TimeSpan(begin, end))).forEach((e) => {
           if (!e.part.begin.equals(e.whole.begin)) {
             return;
           }
@@ -16,13 +19,20 @@ class Scheduler {
         });
       },
       interval,
-      lookahead,
     );
   }
   start() {
-    this.metro.start();
+    if (!this.pattern) {
+      throw new Error('Scheduler: no pattern set! call .setPattern first.');
+    }
+    this.worker.start();
   }
   stop() {
-    this.metro.stop();
+    this.worker.stop();
+  }
+  setPattern(pat) {
+    this.pattern = pat;
   }
 }
+
+export default Scheduler;

packages/webaudio/webaudio.mjs

@@ -1,7 +1,12 @@
 import { Pattern } from '@strudel.cycles/core';
 
 let audioContext;
-export const getAudioContext = () => audioContext || new AudioContext();
+export const getAudioContext = () => {
+  if (!audioContext) {
+    audioContext = new AudioContext();
+  }
+  return audioContext;
+};
 
 const lookahead = 0.2;