webpd/dist/src/build/outputs/audio.js

WebPd is a compiler for audio programming language Pure Data allowing to run .pd patches on web pages.

import { WaveFile } from '../../../node_modules/wavefile/index.js';
import { getArtefact } from '../helpers.js';
import { createEngine as createEngine$1 } from '../../../node_modules/@webpd/compiler/dist/src/engine-assemblyscript/run/index.js';
import { createEngine as createEngine$2 } from '../../../node_modules/@webpd/compiler/dist/src/engine-javascript/run/index.js';
import { getFloatArrayType } from '../../../node_modules/@webpd/compiler/dist/src/run/run-helpers.js';

/*
 * Copyright (c) 2022-2023 Sébastien Piquemal <sebpiq@protonmail.com>, Chris McCormick.
 *
 * This file is part of WebPd
 * (see https://github.com/sebpiq/WebPd).
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
const renderWav = async (durationSeconds, artefacts, audioSettings) => {
    let target = 'assemblyscript';
    if (!artefacts.wasm && !artefacts.javascript) {
        throw new Error(`Need compiled wasm or compiled js to render wav`);
    }
    if (!artefacts.wasm) {
        target = 'javascript';
    }
    const engine = await createEngine(artefacts, target);
    const audioData = await renderAudioData(engine, durationSeconds, audioSettings);
    return audioDataToWav(audioData, audioSettings.sampleRate);
};
const audioDataToWav = (audioData, sampleRate) => {
    const channelCount = audioData.length;
    let wav = new WaveFile();
    wav.fromScratch(channelCount, sampleRate, '32f', audioData.map((channelData) => channelData.map((v) => v)));
    return wav.toBuffer();
};
const createEngine = async (artefacts, target) => {
    switch (target) {
        case 'javascript':
            return createEngine$2(getArtefact(artefacts, 'javascript'));
        case 'assemblyscript':
            return createEngine$1(getArtefact(artefacts, 'wasm'));
    }
};
const renderAudioData = (engine, durationSeconds, audioSettings) => {
    const { channelCount, sampleRate, blockSize } = audioSettings;
    const durationSamples = Math.round(durationSeconds * sampleRate);
    const blockInput = _makeBlock('in', audioSettings);
    const blockOutput = _makeBlock('out', audioSettings);
    const output = _makeBlock('out', audioSettings, durationSamples);
    engine.initialize(sampleRate, blockSize);
    let frame = 0;
    while (frame < durationSamples) {
        engine.dspLoop(blockInput, blockOutput);
        for (let channel = 0; channel < channelCount.out; channel++) {
            output[channel].set(blockOutput[channel].slice(0, Math.min(blockSize, durationSamples - frame)), frame);
        }
        frame += blockSize;
    }
    return output;
};
const _makeBlock = (inOrOut, audioSettings, blockSize) => {
    const { channelCount, blockSize: defaultBlockSize, bitDepth, } = audioSettings;
    if (blockSize === undefined) {
        blockSize = defaultBlockSize;
    }
    const floatArrayType = getFloatArrayType(bitDepth);
    const block = [];
    for (let channel = 0; channel < channelCount[inOrOut]; channel++) {
        block.push(new floatArrayType(Math.round(blockSize)));
    }
    return block;
};

export { renderWav };