godot-ultimate-tutorial/web/Tutorial.audio.worklet.js
2023-08-15 22:51:29 +02:00

214 lines
7.0 KiB
JavaScript

/**************************************************************************/
/* audio.worklet.js */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
class RingBuffer {
constructor(p_buffer, p_state, p_threads) {
this.buffer = p_buffer;
this.avail = p_state;
this.threads = p_threads;
this.rpos = 0;
this.wpos = 0;
}
data_left() {
return this.threads ? Atomics.load(this.avail, 0) : this.avail;
}
space_left() {
return this.buffer.length - this.data_left();
}
read(output) {
const size = this.buffer.length;
let from = 0;
let to_write = output.length;
if (this.rpos + to_write > size) {
const high = size - this.rpos;
output.set(this.buffer.subarray(this.rpos, size));
from = high;
to_write -= high;
this.rpos = 0;
}
if (to_write) {
output.set(this.buffer.subarray(this.rpos, this.rpos + to_write), from);
}
this.rpos += to_write;
if (this.threads) {
Atomics.add(this.avail, 0, -output.length);
Atomics.notify(this.avail, 0);
} else {
this.avail -= output.length;
}
}
write(p_buffer) {
const to_write = p_buffer.length;
const mw = this.buffer.length - this.wpos;
if (mw >= to_write) {
this.buffer.set(p_buffer, this.wpos);
this.wpos += to_write;
if (mw === to_write) {
this.wpos = 0;
}
} else {
const high = p_buffer.subarray(0, mw);
const low = p_buffer.subarray(mw);
this.buffer.set(high, this.wpos);
this.buffer.set(low);
this.wpos = low.length;
}
if (this.threads) {
Atomics.add(this.avail, 0, to_write);
Atomics.notify(this.avail, 0);
} else {
this.avail += to_write;
}
}
}
class GodotProcessor extends AudioWorkletProcessor {
constructor() {
super();
this.threads = false;
this.running = true;
this.lock = null;
this.notifier = null;
this.output = null;
this.output_buffer = new Float32Array();
this.input = null;
this.input_buffer = new Float32Array();
this.port.onmessage = (event) => {
const cmd = event.data['cmd'];
const data = event.data['data'];
this.parse_message(cmd, data);
};
}
process_notify() {
if (this.notifier) {
Atomics.add(this.notifier, 0, 1);
Atomics.notify(this.notifier, 0);
}
}
parse_message(p_cmd, p_data) {
if (p_cmd === 'start' && p_data) {
const state = p_data[0];
let idx = 0;
this.threads = true;
this.lock = state.subarray(idx, ++idx);
this.notifier = state.subarray(idx, ++idx);
const avail_in = state.subarray(idx, ++idx);
const avail_out = state.subarray(idx, ++idx);
this.input = new RingBuffer(p_data[1], avail_in, true);
this.output = new RingBuffer(p_data[2], avail_out, true);
} else if (p_cmd === 'stop') {
this.running = false;
this.output = null;
this.input = null;
this.lock = null;
this.notifier = null;
} else if (p_cmd === 'start_nothreads') {
this.output = new RingBuffer(p_data[0], p_data[0].length, false);
} else if (p_cmd === 'chunk') {
this.output.write(p_data);
}
}
static array_has_data(arr) {
return arr.length && arr[0].length && arr[0][0].length;
}
process(inputs, outputs, parameters) {
if (!this.running) {
return false; // Stop processing.
}
if (this.output === null) {
return true; // Not ready yet, keep processing.
}
const process_input = GodotProcessor.array_has_data(inputs);
if (process_input) {
const input = inputs[0];
const chunk = input[0].length * input.length;
if (this.input_buffer.length !== chunk) {
this.input_buffer = new Float32Array(chunk);
}
if (!this.threads) {
GodotProcessor.write_input(this.input_buffer, input);
this.port.postMessage({ 'cmd': 'input', 'data': this.input_buffer });
} else if (this.input.space_left() >= chunk) {
GodotProcessor.write_input(this.input_buffer, input);
this.input.write(this.input_buffer);
} else {
this.port.postMessage('Input buffer is full! Skipping input frame.');
}
}
const process_output = GodotProcessor.array_has_data(outputs);
if (process_output) {
const output = outputs[0];
const chunk = output[0].length * output.length;
if (this.output_buffer.length !== chunk) {
this.output_buffer = new Float32Array(chunk);
}
if (this.output.data_left() >= chunk) {
this.output.read(this.output_buffer);
GodotProcessor.write_output(output, this.output_buffer);
if (!this.threads) {
this.port.postMessage({ 'cmd': 'read', 'data': chunk });
}
} else {
this.port.postMessage('Output buffer has not enough frames! Skipping output frame.');
}
}
this.process_notify();
return true;
}
static write_output(dest, source) {
const channels = dest.length;
for (let ch = 0; ch < channels; ch++) {
for (let sample = 0; sample < dest[ch].length; sample++) {
dest[ch][sample] = source[sample * channels + ch];
}
}
}
static write_input(dest, source) {
const channels = source.length;
for (let ch = 0; ch < channels; ch++) {
for (let sample = 0; sample < source[ch].length; sample++) {
dest[sample * channels + ch] = source[ch][sample];
}
}
}
}
registerProcessor('godot-processor', GodotProcessor);