p8-data-cart/dist/music.js

Simple tools for generating Pico-8 data carts.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.cartBytesToMusicData = cartBytesToMusicData;
exports.musicDataToCartBytes = musicDataToCartBytes;
exports.runtimeBytesToMusicData = runtimeBytesToMusicData;
exports.musicDataToRuntimeBytes = musicDataToRuntimeBytes;
function cartBytesToMusicData(bytes) {
    const frames = [];
    for (let i = 0; i < bytes.length; i += 5) {
        const firstByte = bytes[i + 0] ?? 0;
        const secondByte = bytes[i + 1] ?? 0;
        const thirdByte = bytes[i + 2] ?? 0;
        const fourthByte = bytes[i + 3] ?? 0;
        const fifthByte = bytes[i + 4] ?? 0;
        frames.push({
            channels: [secondByte & 0x7f, thirdByte & 0x7f, fourthByte & 0x7f, fifthByte & 0x7f],
            flags: {
                loopStart: (firstByte & 0x01) != 0,
                loopEnd: (firstByte & 0x02) != 0,
                stop: (firstByte & 0x04) != 0,
                unused: (firstByte & 0x08) != 0
            }
        });
    }
    return frames;
}
function musicDataToCartBytes(musicData) {
    const bytes = new Uint8Array(musicData.length * 5);
    for (let i = 0; i < musicData.length; i++) {
        const frame = musicData[i];
        const baseIndex = i * 5;
        bytes[baseIndex + 0] = (frame.flags.loopStart ? 0x01 : 0)
            | (frame.flags.loopEnd ? 0x02 : 0)
            | (frame.flags.stop ? 0x04 : 0)
            | (frame.flags.unused ? 0x08 : 0);
        bytes[baseIndex + 1] = frame.channels[0];
        bytes[baseIndex + 2] = frame.channels[1];
        bytes[baseIndex + 3] = frame.channels[2];
        bytes[baseIndex + 4] = frame.channels[3];
    }
    return bytes;
}
function runtimeBytesToMusicData(bytes) {
    const frames = [];
    for (let i = 0; i < bytes.length; i += 4) {
        const firstByte = bytes[i + 0] ?? 0;
        const secondByte = bytes[i + 1] ?? 0;
        const thirdByte = bytes[i + 2] ?? 0;
        const fourthByte = bytes[i + 3] ?? 0;
        frames.push({
            channels: [firstByte & 0x7f, secondByte & 0x7f, thirdByte & 0x7f, fourthByte & 0x7f],
            flags: {
                loopStart: (firstByte & 0x80) != 0,
                loopEnd: (secondByte & 0x80) != 0,
                stop: (thirdByte & 0x80) != 0,
                unused: (fourthByte & 0x80) != 0
            }
        });
    }
    return frames;
}
function musicDataToRuntimeBytes(musicData) {
    const bytes = new Uint8Array(musicData.length * 4);
    for (let i = 0; i < musicData.length; i++) {
        const frame = musicData[i];
        const baseIndex = i * 4;
        bytes[baseIndex + 0] = (frame.channels[0] & 0x7f) | (frame.flags.loopStart ? 0x80 : 0);
        bytes[baseIndex + 1] = (frame.channels[1] & 0x7f) | (frame.flags.loopEnd ? 0x80 : 0);
        bytes[baseIndex + 2] = (frame.channels[2] & 0x7f) | (frame.flags.stop ? 0x80 : 0);
        bytes[baseIndex + 3] = (frame.channels[3] & 0x7f) | (frame.flags.unused ? 0x80 : 0);
    }
    return bytes;
}