Files
topos/src/TransportNode.js

58 lines
1.8 KiB
JavaScript

import { tryEvaluate } from "./Evaluator";
const zeroPad = (num, places) => String(num).padStart(places, '0')
export class TransportNode extends AudioWorkletNode {
constructor(context, options, application) {
super(context, "transport", options);
this.app = application
this.port.addEventListener("message", this.handleMessage);
this.port.start();
this.logicalTime = 0;
}
/** @type {(this: MessagePort, ev: MessageEvent<any>) => any} */
handleMessage = (message) => {
if (message.data && message.data.type === "bang") {
this.logicalTime = message.data.logicalTime;
const futureTimeStamp = this.convertTicksToTimeposition(this.app.clock.tick);
// console.log("BANG", this.logicalTime, futureTimeStamp);
this.app.clock.time_position = futureTimeStamp;
tryEvaluate(this.app, this.app.global_buffer);
}
};
convertTicksToTimeposition(ticks) {
const beatsPerBar = this.app.clock.time_signature[0];
const ppqnPosition = (ticks % this.app.clock.ppqn)+1;
const beatNumber = Math.floor(ticks / this.app.clock.ppqn);
const barNumber = Math.floor(beatNumber / beatsPerBar)+1;
const beatWithinBar = Math.floor(beatNumber % beatsPerBar)+1;
this.app.clock.tick++
return {bar: barNumber, beat: beatWithinBar, pulse: ppqnPosition};
}
start() {
this.port.postMessage("start");
}
pause() {
this.port.postMessage("pause");
}
setBPM(bpm) {
this.port.postMessage({ type: "bpm", value: bpm });
}
setPPQN(ppqn) {
this.port.postMessage({ type: "ppqn", value: ppqn });
}
stop() {
this.port.postMessage("stop");
}
}