From 90624abf2e2d1f9b3ad7a7b8e7725f1cd4b10ddb Mon Sep 17 00:00:00 2001
From: "Jade (Rose) Rowland" <jaderowlanddev@gmail.com>
Date: Sun, 4 Feb 2024 13:54:40 -0500
Subject: [PATCH] added worker, cleaned up, added setcps function

---
 packages/core/clockworker.mjs  | 129 ++++++++++++++
 packages/core/cyclist.mjs      | 301 +++++++++++++++++++++++++--------
 packages/core/cyclistworker.js | 154 -----------------
 packages/core/repl.mjs         | 140 ++++++++-------
 packages/core/zyklus.mjs       |  49 ------
 5 files changed, 426 insertions(+), 347 deletions(-)
 create mode 100644 packages/core/clockworker.mjs
 delete mode 100644 packages/core/cyclistworker.js
 delete mode 100644 packages/core/zyklus.mjs

diff --git a/packages/core/clockworker.mjs b/packages/core/clockworker.mjs
new file mode 100644
index 00000000..906e914f
--- /dev/null
+++ b/packages/core/clockworker.mjs
@@ -0,0 +1,129 @@
+function getTime(precision) {
+  const seconds = performance.now() / 1000;
+  return Math.round(seconds * precision) / precision;
+}
+const allPorts = [];
+let num_cycles_at_cps_change = 0;
+let num_ticks_since_cps_change = 0;
+let cps = 0.5;
+const duration = 0.1;
+
+const sendMessage = (type, payload) => {
+  allPorts.forEach((port) => {
+    port.postMessage({ type, payload });
+  });
+};
+
+const sendTick = ({ phase, duration, time }) => {
+  sendMessage('tick', {
+    phase,
+    duration,
+    time,
+    cps,
+    num_cycles_at_cps_change,
+    num_ticks_since_cps_change,
+  });
+  num_ticks_since_cps_change++;
+};
+
+const clock = createClock(sendTick, duration);
+let started = false;
+
+const startClock = () => {
+  if (started) {
+    return;
+  }
+  clock.start();
+  started = true;
+};
+const stopClock = () => {
+  //dont stop the clock if mutliple instances are using it...
+  if (!started || numClientsConnected() > 1) {
+    return;
+  }
+  clock.stop();
+  setCycle(0);
+  started = false;
+};
+
+const setCycle = (cycle) => {
+  num_ticks_since_cps_change = 0;
+  num_cycles_at_cps_change = cycle;
+};
+
+const numClientsConnected = () => allPorts.length;
+const processMessage = (message) => {
+  const { type, payload } = message;
+
+  switch (type) {
+    case 'cpschange': {
+      if (payload.cps !== cps) {
+        num_cycles_at_cps_change = num_cycles_at_cps_change + num_ticks_since_cps_change * duration * cps;
+        cps = payload.cps;
+        num_ticks_since_cps_change = 0;
+      }
+      break;
+    }
+    case 'setcycle': {
+      setCycle(payload.cycle);
+      break;
+    }
+    case 'toggle': {
+      if (payload.started) {
+        startClock();
+      } else {
+        stopClock();
+      }
+      break;
+    }
+  }
+};
+
+self.onconnect = function (e) {
+  // the incoming port
+  const port = e.ports[0];
+  allPorts.push(port);
+  port.addEventListener('message', function (e) {
+    processMessage(e.data);
+  });
+  port.start(); // Required when using addEventListener. Otherwise called implicitly by onmessage setter.
+};
+
+function createClock(
+  callback, // called slightly before each cycle
+  duration,
+) {
+  const interval = 0.1;
+  const overlap = interval / 2;
+  const precision = 10 ** 4; // used to round phase
+  const minLatency = 0.01;
+  let phase = 0; // next callback time
+
+  const onTick = () => {
+    const t = getTime(precision);
+    const lookahead = t + interval + overlap; // the time window for this tick
+    if (phase === 0) {
+      phase = t + minLatency;
+    }
+    // callback as long as we're inside the lookahead
+    while (phase < lookahead) {
+      phase = Math.round(phase * precision) / precision;
+      phase >= t && callback({ phase, duration, time: t });
+      phase < t && console.log('TOO LATE', phase); // what if latency is added from outside?
+      phase += duration; // increment phase by duration
+    }
+  };
+  let intervalID;
+  const start = () => {
+    clear(); // just in case start was called more than once
+    onTick();
+    intervalID = setInterval(onTick, interval * 1000);
+  };
+  const clear = () => intervalID !== undefined && clearInterval(intervalID);
+  const stop = () => {
+    phase = 0;
+    clear();
+  };
+
+  return { start, stop };
+}
diff --git a/packages/core/cyclist.mjs b/packages/core/cyclist.mjs
index 2afbe9c7..f44b015e 100644
--- a/packages/core/cyclist.mjs
+++ b/packages/core/cyclist.mjs
@@ -1,96 +1,133 @@
 /*
-cyclist.mjs - <short description TODO>
+cyclist.mjs - recieves clock pulses from clockworker, and schedules the next events
 Copyright (C) 2022 Strudel contributors - see <https://github.com/tidalcycles/strudel/blob/main/packages/core/cyclist.mjs>
 This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-import createClock from './zyklus.mjs';
 import { logger } from './logger.mjs';
 
 export class Cyclist {
-  constructor({ interval, onTrigger, onToggle, onError, getTime, latency = 0.1 }) {
+  constructor({ onTrigger, onToggle, getTime }) {
     this.started = false;
     this.cps = 0.5;
-    this.num_ticks_since_cps_change = 0;
     this.lastTick = 0; // absolute time when last tick (clock callback) happened
-    this.lastBegin = 0; // query begin of last tick
-    this.lastEnd = 0; // query end of last tick
     this.getTime = getTime; // get absolute time
+
     this.num_cycles_at_cps_change = 0;
     this.onToggle = onToggle;
-    this.latency = latency; // fixed trigger time offset
-    this.nextCycleStartTime = 0;
+    this.latency = 0.1; // fixed trigger time offset
+    this.cycle = 0;
 
-    this.clock = createClock(
-      getTime,
-      // called slightly before each cycle
-      (phase, duration, tick) => {
-        if (tick === 0) {
-          this.origin = phase;
+    this.worker = new SharedWorker(new URL('./clockworker.mjs', import.meta.url));
+    this.worker.port.start();
+    let worker_time_dif = 0; // time difference between audio context clock and worker clock
+    let weight = 0; // the amount of weight that is applied to the current average when averaging a new time dif
+    const maxWeight = 400;
+    const precision = 10 ** 3; //round off time diff to prevent accumulating outliers
+
+    // the clock of the worker and the audio context clock can drift apart over time
+    // aditionally, the message time of the worker pinging the callback to process haps can be inconsistent.
+    // we need to keep a rolling weighted average of the time difference between the worker clock and audio context clock
+    // in order to schedule events consistently.
+    const setTimeReference = (time, workertime) => {
+      const time_dif = workertime - time;
+      if (worker_time_dif === 0) {
+        worker_time_dif = time_dif;
+      } else {
+        const w = 1; //weight of new time diff;
+        const new_dif = Math.round(((worker_time_dif * weight + time_dif * w) / (weight + w)) * precision) / precision;
+
+        if (new_dif != worker_time_dif) {
+          // reset the weight so the clock recovers faster from an audio context freeze/dropout if it happens
+          weight = 4;
         }
-        if (this.num_ticks_since_cps_change === 0) {
-          this.num_cycles_at_cps_change = this.lastEnd;
+        worker_time_dif = new_dif;
+      }
+    };
+
+    const getTickDeadline = (phase, time) => {
+      return phase - time - worker_time_dif;
+    };
+
+    const tickCallback = (payload) => {
+      const workertime = payload.time;
+      const time = this.getTime();
+      const { duration, phase, num_ticks_since_cps_change, num_cycles_at_cps_change, cps } = payload;
+      setTimeReference(time, workertime);
+      this.cps = cps;
+
+      //calculate begin and end
+      const eventLength = duration * cps;
+      const num_cycles_since_cps_change = num_ticks_since_cps_change * eventLength;
+      const begin = num_cycles_at_cps_change + num_cycles_since_cps_change;
+      const tickdeadline = getTickDeadline(phase, time);
+      const end = begin + eventLength;
+
+      //calculate current cycle
+      const lastTick = time + tickdeadline;
+      const secondsSinceLastTick = time - lastTick - duration;
+      this.cycle = begin + secondsSinceLastTick * cps;
+
+      //set the weight of average time diff and processs haps
+      weight = Math.min(weight + 1, maxWeight);
+      processHaps(begin, end, tickdeadline);
+      this.time_at_last_tick_message = this.getTime();
+    };
+
+    const processHaps = (begin, end, tickdeadline) => {
+      if (this.started === false) {
+        return;
+      }
+      const haps = this.pattern.queryArc(begin, end, { _cps: this.cps });
+
+      haps.forEach((hap) => {
+        if (hap.part.begin.equals(hap.whole.begin)) {
+          const deadline = (hap.whole.begin - begin) / this.cps + tickdeadline + this.latency;
+          const duration = hap.duration / this.cps;
+          onTrigger?.(hap, deadline, duration, this.cps);
         }
-        this.num_ticks_since_cps_change++;
-        try {
-          const time = getTime();
-          const begin = this.lastEnd;
-          this.lastBegin = begin;
-          //convert ticks to cycles, so you can query the pattern for events
-          const eventLength = duration * this.cps;
-          const num_cycles_since_cps_change = this.num_ticks_since_cps_change * eventLength;
-          const end = this.num_cycles_at_cps_change + num_cycles_since_cps_change;
-          this.lastEnd = end;
+      });
+    };
 
-          // query the pattern for events
-          const haps = this.pattern.queryArc(begin, end, { _cps: this.cps });
+    // receive messages from worker clock and process them
+    this.worker.port.addEventListener('message', (message) => {
+      if (!this.started) {
+        return;
+      }
+      const { payload, type } = message.data;
 
-          const tickdeadline = phase - time; // time left until the phase is a whole number
-
-          this.lastTick = time + tickdeadline;
-
-          haps.forEach((hap) => {
-            if (hap.part.begin.equals(hap.whole.begin)) {
-              const deadline = (hap.whole.begin - begin) / this.cps + tickdeadline + latency;
-              const duration = hap.duration / this.cps;
-              onTrigger?.(hap, deadline, duration, this.cps);
-            }
-          });
-        } catch (e) {
-          logger(`[cyclist] error: ${e.message}`);
-          onError?.(e);
+      switch (type) {
+        case 'tick': {
+          tickCallback(payload);
         }
-      },
-      interval, // duration of each cycle
-    );
+      }
+    });
   }
+  sendMessage(type, payload) {
+    this.worker.port.postMessage({ type, payload });
+  }
+
   now() {
-    const secondsSinceLastTick = this.getTime() - this.lastTick - this.clock.duration;
-    return this.lastBegin + secondsSinceLastTick * this.cps; // + this.clock.minLatency;
+    const gap = (this.getTime() - this.time_at_last_tick_message) * this.cps;
+    return this.cycle + gap;
   }
-  setStarted(v) {
-    this.started = v;
-    this.onToggle?.(v);
+  setCps(cps = 1) {
+    this.sendMessage('cpschange', { cps });
+  }
+  setCycle(cycle) {
+    this.sendMessage('setcycle', { cycle });
+  }
+  setStarted(started) {
+    this.sendMessage('toggle', { started });
+    this.started = started;
+    this.onToggle?.(started);
   }
   start() {
-    this.num_ticks_since_cps_change = 0;
-    this.num_cycles_at_cps_change = 0;
-    if (!this.pattern) {
-      throw new Error('Scheduler: no pattern set! call .setPattern first.');
-    }
     logger('[cyclist] start');
-    this.clock.start();
     this.setStarted(true);
   }
-  pause() {
-    logger('[cyclist] pause');
-    this.clock.pause();
-    this.setStarted(false);
-  }
   stop() {
     logger('[cyclist] stop');
-    this.clock.stop();
-    this.lastEnd = 0;
     this.setStarted(false);
   }
   setPattern(pat, autostart = false) {
@@ -99,15 +136,139 @@ export class Cyclist {
       this.start();
     }
   }
-  setCps(cps = 0.5) {
-    if (this.cps === cps) {
-      return;
-    }
-    this.cps = cps;
-    this.num_ticks_since_cps_change = 0;
-  }
+
   log(begin, end, haps) {
     const onsets = haps.filter((h) => h.hasOnset());
     console.log(`${begin.toFixed(4)} - ${end.toFixed(4)} ${Array(onsets.length).fill('I').join('')}`);
   }
 }
+
+function getTime(precision) {
+  const seconds = performance.now() / 1000;
+  return Math.round(seconds * precision) / precision;
+}
+const allPorts = [];
+let num_cycles_at_cps_change = 0;
+let num_ticks_since_cps_change = 0;
+let cps = 0.5;
+const duration = 0.1;
+
+const sendMessage = (type, payload) => {
+  allPorts.forEach((port) => {
+    port.postMessage({ type, payload });
+  });
+};
+
+const sendTick = ({ phase, duration, time }) => {
+  sendMessage('tick', {
+    phase,
+    duration,
+    time,
+    cps,
+    num_cycles_at_cps_change,
+    num_ticks_since_cps_change,
+  });
+  num_ticks_since_cps_change++;
+};
+
+const clock = createClock(sendTick, duration);
+let started = false;
+
+const startClock = () => {
+  if (started) {
+    return;
+  }
+  clock.start();
+  started = true;
+};
+const stopClock = () => {
+  //dont stop the clock if mutliple instances are using it...
+  if (!started || numClientsConnected() > 1) {
+    return;
+  }
+  clock.stop();
+  setCycle(0);
+  started = false;
+};
+
+const setCycle = (cycle) => {
+  num_ticks_since_cps_change = 0;
+  num_cycles_at_cps_change = cycle;
+};
+
+const numClientsConnected = () => allPorts.length;
+const processMessage = (message) => {
+  const { type, payload } = message;
+
+  switch (type) {
+    case 'cpschange': {
+      if (payload.cps !== cps) {
+        num_cycles_at_cps_change = num_cycles_at_cps_change + num_ticks_since_cps_change * duration * cps;
+        cps = payload.cps;
+        num_ticks_since_cps_change = 0;
+      }
+      break;
+    }
+    case 'setcycle': {
+      setCycle(payload.cycle);
+      break;
+    }
+    case 'toggle': {
+      if (payload.started) {
+        startClock();
+      } else {
+        stopClock();
+      }
+      break;
+    }
+  }
+};
+
+self.onconnect = function (e) {
+  // the incoming port
+  const port = e.ports[0];
+  allPorts.push(port);
+  port.addEventListener('message', function (e) {
+    processMessage(e.data);
+  });
+  port.start(); // Required when using addEventListener. Otherwise called implicitly by onmessage setter.
+};
+
+function createClock(
+  callback, // called slightly before each cycle
+  duration,
+) {
+  const interval = 0.1;
+  const overlap = interval / 2;
+  const precision = 10 ** 4; // used to round phase
+  const minLatency = 0.01;
+  let phase = 0; // next callback time
+
+  const onTick = () => {
+    const t = getTime(precision);
+    const lookahead = t + interval + overlap; // the time window for this tick
+    if (phase === 0) {
+      phase = t + minLatency;
+    }
+    // callback as long as we're inside the lookahead
+    while (phase < lookahead) {
+      phase = Math.round(phase * precision) / precision;
+      phase >= t && callback({ phase, duration, time: t });
+      phase < t && console.log('TOO LATE', phase); // what if latency is added from outside?
+      phase += duration; // increment phase by duration
+    }
+  };
+  let intervalID;
+  const start = () => {
+    clear(); // just in case start was called more than once
+    onTick();
+    intervalID = setInterval(onTick, interval * 1000);
+  };
+  const clear = () => intervalID !== undefined && clearInterval(intervalID);
+  const stop = () => {
+    phase = 0;
+    clear();
+  };
+
+  return { start, stop };
+}
diff --git a/packages/core/cyclistworker.js b/packages/core/cyclistworker.js
deleted file mode 100644
index 2357c0df..00000000
--- a/packages/core/cyclistworker.js
+++ /dev/null
@@ -1,154 +0,0 @@
-const allPorts = [];
-let cps = 1;
-let num_ticks_since_cps_change = 0;
-let lastTick = 0; // absolute time when last tick (clock callback) happened
-let lastBegin = 0; // query begin of last tick
-let lastEnd = 0; // query end of last tick
-let num_cycles_at_cps_change = 0;
-let interval = 0.1;
-let started = false;
-
-//incoming
-//cps message
-// {type: 'cpschange', payload: {cps}}
-
-//toggle
-// {type: toggle, payload?: {started: boolean}}
-
-//sending
-//{type: 'tick', payload: {begin, end, tickdeadline, cps, time }}
-//{type: 'log', payload: {type, text}}
-
-const getTime = () => {
-  return performance.now() / 1000;
-};
-
-const sendMessage = (type, payload) => {
-  allPorts.forEach((port) => {
-    port.postMessage({ type, payload });
-  });
-};
-const log = (text, type) => {
-  sendMessage('log', { text, type });
-};
-
-const numClientsConnected = () => allPorts.length;
-
-const getCycle = () => {
-  const secondsSinceLastTick = getTime() - lastTick - clock.duration;
-  const cycle = lastBegin + secondsSinceLastTick * cps;
-  return cycle;
-};
-// let prevtime = 0;
-let clock = createClock(
-  getTime,
-  // called slightly before each cycle
-  (phase, duration, tick) => {
-    if (num_ticks_since_cps_change === 0) {
-      num_cycles_at_cps_change = lastEnd;
-    }
-    num_ticks_since_cps_change++;
-    // const now = Date.now();
-    // console.log('interval', now - prevtime);
-    // prevtime = now;
-    try {
-      const time = getTime();
-      const begin = lastEnd;
-      lastBegin = begin;
-      //convert ticks to cycles, so you can query the pattern for events
-      const eventLength = duration * cps;
-      const num_cycles_since_cps_change = num_ticks_since_cps_change * eventLength;
-      const end = num_cycles_at_cps_change + num_cycles_since_cps_change;
-      lastEnd = end;
-      const tickdeadline = phase - time; // time left until the phase is a whole number
-      lastTick = time + tickdeadline;
-      sendMessage('tick', { begin, end, tickdeadline, cps, cycle: getCycle() });
-    } catch (e) {
-      log(`[cyclist] error: ${e.message}`, 'error');
-    }
-  },
-  interval, // duration of each cycle
-);
-
-self.onconnect = function (e) {
-  // the incoming port
-  const port = e.ports[0];
-  allPorts.push(port);
-  port.addEventListener('message', function (e) {
-    processMessage(e.data);
-  });
-  port.start(); // Required when using addEventListener. Otherwise called implicitly by onmessage setter.
-};
-
-const processMessage = (message) => {
-  const { type, payload } = message;
-
-  switch (type) {
-    case 'cpschange': {
-      if (payload.cps !== cps) {
-        cps = payload.cps;
-        num_ticks_since_cps_change = 0;
-      }
-      break;
-    }
-    case 'toggle': {
-      if (payload.started && !started) {
-        started = true;
-        clock.start();
-        //dont stop the clock if others are using it...
-      } else if (numClientsConnected() === 1) {
-        started = false;
-        clock.stop();
-      }
-      break;
-    }
-  }
-};
-
-function createClock(
-  getTime,
-  callback, // called slightly before each cycle
-  duration = 0.05, // duration of each cycle
-  interval = 0.1, // interval between callbacks
-  overlap = 0.1, // overlap between callbacks
-) {
-  let tick = 0; // counts callbacks
-  let phase = 0; // next callback time
-  let precision = 10 ** 4; // used to round phase
-  let minLatency = 0.01;
-
-  const setDuration = (setter) => (duration = setter(duration));
-  overlap = overlap || interval / 2;
-  const onTick = () => {
-    const t = getTime();
-    const lookahead = t + interval + overlap; // the time window for this tick
-    if (phase === 0) {
-      phase = t + minLatency;
-    }
-
-    // callback as long as we're inside the lookahead
-    while (phase < lookahead) {
-      phase = Math.round(phase * precision) / precision;
-      phase >= t && callback(phase, duration, tick);
-      phase < t && console.log('TOO LATE', phase); // what if latency is added from outside?
-      phase += duration; // increment phase by duration
-      tick++;
-    }
-  };
-  let intervalID;
-  const start = () => {
-    clear(); // just in case start was called more than once
-    onTick();
-    intervalID = setInterval(onTick, interval * 1000);
-  };
-  const clear = () => intervalID !== undefined && clearInterval(intervalID);
-  const pause = () => clear();
-  const stop = () => {
-    tick = 0;
-    phase = 0;
-    clear();
-  };
-  const getPhase = () => phase;
-
-  return { setDuration, start, stop, pause, duration, interval, getPhase, minLatency };
-}
diff --git a/packages/core/repl.mjs b/packages/core/repl.mjs
index 41a7d691..db58e61e 100644
--- a/packages/core/repl.mjs
+++ b/packages/core/repl.mjs
@@ -4,12 +4,10 @@ import { logger } from './logger.mjs';
 import { setTime } from './time.mjs';
 import { evalScope } from './evaluate.mjs';
 import { register, Pattern, isPattern, silence, stack } from './pattern.mjs';
-import { NeoCyclist } from './neocyclist.mjs';
 
 export function repl({
-  interval,
   defaultOutput,
-  onSchedulerError,
+
   onEvalError,
   beforeEval,
   afterEval,
@@ -38,28 +36,14 @@ export function repl({
     onUpdateState?.(state);
   };
 
-  // const scheduler = new Cyclist({
-  //   interval,
-  //   onTrigger: getTrigger({ defaultOutput, getTime }),
-  //   onError: onSchedulerError,
-  //   getTime,
-  //   onToggle: (started) => {
-  //     updateState({ started });
-  //     onToggle?.(started);
-  //   },
-  // });
-
-  const scheduler = new NeoCyclist({
-    // interval,
+  const scheduler = new Cyclist({
     onTrigger: getTrigger({ defaultOutput, getTime }),
-    onError: onSchedulerError,
-    // latency: 0.22,
+    getTime,
     onToggle: (started) => {
       updateState({ started });
       onToggle?.(started);
     },
   });
-
   let pPatterns = {};
   let allTransform;
 
@@ -74,67 +58,12 @@ export function repl({
     scheduler.setPattern(pattern, autostart);
   };
   setTime(() => scheduler.now()); // TODO: refactor?
-
-  const stop = () => scheduler.stop();
-  const start = () => scheduler.start();
-  const pause = () => scheduler.pause();
-  const toggle = () => scheduler.toggle();
-  const setCps = (cps) => scheduler.setCps(cps);
-  const setCpm = (cpm) => scheduler.setCps(cpm / 60);
-  const all = function (transform) {
-    allTransform = transform;
-    return silence;
-  };
-
-  // set pattern methods that use this repl via closure
-  const injectPatternMethods = () => {
-    Pattern.prototype.p = function (id) {
-      pPatterns[id] = this;
-      return this;
-    };
-    Pattern.prototype.q = function (id) {
-      return silence;
-    };
-    try {
-      for (let i = 1; i < 10; ++i) {
-        Object.defineProperty(Pattern.prototype, `d${i}`, {
-          get() {
-            return this.p(i);
-          },
-          configurable: true,
-        });
-        Object.defineProperty(Pattern.prototype, `p${i}`, {
-          get() {
-            return this.p(i);
-          },
-          configurable: true,
-        });
-        Pattern.prototype[`q${i}`] = silence;
-      }
-    } catch (err) {
-      console.warn('injectPatternMethods: error:', err);
-    }
-    const cpm = register('cpm', function (cpm, pat) {
-      return pat._fast(cpm / 60 / scheduler.cps);
-    });
-    evalScope({
-      all,
-      hush,
-      cpm,
-      setCps,
-      setcps: setCps,
-      setCpm,
-      setcpm: setCpm,
-    });
-  };
-
   const evaluate = async (code, autostart = true, shouldHush = true) => {
     if (!code) {
       throw new Error('no code to evaluate');
     }
     try {
       updateState({ code, pending: true });
-      injectPatternMethods();
       await beforeEval?.({ code });
       shouldHush && hush();
       let { pattern, meta } = await _evaluate(code, transpiler);
@@ -162,11 +91,74 @@ export function repl({
       afterEval?.({ code, pattern, meta });
       return pattern;
     } catch (err) {
+      // console.warn(`[repl] eval error: ${err.message}`);
       logger(`[eval] error: ${err.message}`, 'error');
       updateState({ evalError: err, pending: false });
       onEvalError?.(err);
     }
   };
+  const stop = () => scheduler.stop();
+  const start = () => scheduler.start();
+  const pause = () => scheduler.pause();
+  const toggle = () => scheduler.toggle();
+  const setCps = (cps) => scheduler.setCps(cps);
+  const setCpm = (cpm) => scheduler.setCps(cpm / 60);
+
+  // the following functions use the cps value, which is why they are defined here..
+  const loopAt = register('loopAt', (cycles, pat) => {
+    return pat.loopAtCps(cycles, scheduler.cps);
+  });
+
+  Pattern.prototype.p = function (id) {
+    pPatterns[id] = this;
+    return this;
+  };
+  Pattern.prototype.q = function (id) {
+    return silence;
+  };
+
+  const all = function (transform) {
+    allTransform = transform;
+    return silence;
+  };
+  try {
+    for (let i = 1; i < 10; ++i) {
+      Object.defineProperty(Pattern.prototype, `d${i}`, {
+        get() {
+          return this.p(i);
+        },
+      });
+      Object.defineProperty(Pattern.prototype, `p${i}`, {
+        get() {
+          return this.p(i);
+        },
+      });
+      Pattern.prototype[`q${i}`] = silence;
+    }
+  } catch (err) {
+    // already defined..
+  }
+
+  const fit = register('fit', (pat) =>
+    pat.withHap((hap) =>
+      hap.withValue((v) => ({
+        ...v,
+        speed: scheduler.cps / hap.whole.duration, // overwrite speed completely?
+        unit: 'c',
+      })),
+    ),
+  );
+
+  evalScope({
+    loopAt,
+    fit,
+    all,
+    hush,
+    setCps,
+    setcps: setCps,
+    setCpm,
+    setcpm: setCpm,
+  });
   const setCode = (code) => updateState({ code });
   return { scheduler, evaluate, start, stop, pause, setCps, setPattern, setCode, toggle, state };
 }
diff --git a/packages/core/zyklus.mjs b/packages/core/zyklus.mjs
deleted file mode 100644
index 3d25b054..00000000
--- a/packages/core/zyklus.mjs
+++ /dev/null
@@ -1,49 +0,0 @@
-// will move to https://github.com/felixroos/zyklus
-// TODO: started flag
-
-function createClock(
-  getTime,
-  callback, // called slightly before each cycle
-  duration = 0.05, // duration of each cycle
-  interval = 0.1, // interval between callbacks
-  overlap = 0.1, // overlap between callbacks
-) {
-  let tick = 0; // counts callbacks
-  let phase = 0; // next callback time
-  let precision = 10 ** 4; // used to round phase
-  let minLatency = 0.01;
-  const setDuration = (setter) => (duration = setter(duration));
-  overlap = overlap || interval / 2;
-  const onTick = () => {
-    const t = getTime();
-    const lookahead = t + interval + overlap; // the time window for this tick
-    if (phase === 0) {
-      phase = t + minLatency;
-    }
-    // callback as long as we're inside the lookahead
-    while (phase < lookahead) {
-      phase = Math.round(phase * precision) / precision;
-      phase >= t && callback(phase, duration, tick);
-      phase < t && console.log('TOO LATE', phase); // what if latency is added from outside?
-      phase += duration; // increment phase by duration
-      tick++;
-    }
-  };
-  let intervalID;
-  const start = () => {
-    clear(); // just in case start was called more than once
-    onTick();
-    intervalID = setInterval(onTick, interval * 1000);
-  };
-  const clear = () => intervalID !== undefined && clearInterval(intervalID);
-  const pause = () => clear();
-  const stop = () => {
-    tick = 0;
-    phase = 0;
-    clear();
-  };
-  const getPhase = () => phase;
-  // setCallback
-  return { setDuration, start, stop, pause, duration, interval, getPhase, minLatency };
-}
-export default createClock;