47 lines
1.5 KiB
JavaScript
47 lines
1.5 KiB
JavaScript
class TransportProcessor extends AudioWorkletProcessor {
|
|
constructor(options) {
|
|
super(options);
|
|
this.port.addEventListener("message", this.handleMessage);
|
|
this.port.start();
|
|
this.nudge = 0;
|
|
this.started = false;
|
|
this.bpm = 120;
|
|
this.ppqn = 48;
|
|
this.currentPulsePosition = 0;
|
|
}
|
|
|
|
handleMessage = (message) => {
|
|
if (message.data && message.data.type === "ping") {
|
|
this.port.postMessage(message.data);
|
|
} else if (message.data.type === "start") {
|
|
this.started = true;
|
|
} else if (message.data.type === "pause") {
|
|
this.started = false;
|
|
} else if (message.data.type === "stop") {
|
|
this.started = false;
|
|
} else if (message.data.type === "bpm") {
|
|
this.bpm = message.data.value;
|
|
this.currentPulsePosition = currentTime;
|
|
} else if (message.data.type === "ppqn") {
|
|
this.ppqn = message.data.value;
|
|
} else if (message.data.type === "nudge") {
|
|
this.nudge = message.data.value;
|
|
}
|
|
};
|
|
|
|
process(inputs, outputs, parameters) {
|
|
if (this.started) {
|
|
const adjustedCurrentTime = currentTime + this.nudge / 100;
|
|
const beatNumber = adjustedCurrentTime / (60 / this.bpm);
|
|
const currentPulsePosition = Math.ceil(beatNumber * this.ppqn);
|
|
if (currentPulsePosition > this.currentPulsePosition) {
|
|
this.currentPulsePosition = currentPulsePosition;
|
|
this.port.postMessage({ type: "bang", bpm: this.bpm });
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
}
|
|
|
|
registerProcessor("transport", TransportProcessor);
|