50 lines
1.4 KiB
JavaScript
50 lines
1.4 KiB
JavaScript
// @ts-check
|
|
|
|
const stream = require("stream")
|
|
const {PNG} = require("pngjs")
|
|
|
|
const SIZE = 160 // Discord's display size on 1x displays is 160
|
|
|
|
/**
|
|
* @typedef RlottieWasm
|
|
* @prop {(string) => boolean} load load lottie data from string of json
|
|
* @prop {() => number} frames get number of frames
|
|
* @prop {(frameCount: number, width: number, height: number) => Uint8Array} render render lottie data to bitmap
|
|
*/
|
|
|
|
const Rlottie = (async () => {
|
|
const Rlottie = require("./rlottie-wasm.js")
|
|
await new Promise(resolve => Rlottie.onRuntimeInitialized = resolve)
|
|
return Rlottie
|
|
})()
|
|
|
|
/**
|
|
* @param {string} text
|
|
* @returns {Promise<import("stream").Readable>}
|
|
*/
|
|
async function convert(text) {
|
|
const r = await Rlottie
|
|
/** @type RlottieWasm */
|
|
const rh = new r.RlottieWasm()
|
|
const status = rh.load(text)
|
|
if (!status) throw new Error(`Rlottie unable to load ${text.length} byte data file.`)
|
|
const rendered = rh.render(0, SIZE, SIZE)
|
|
let png = new PNG({
|
|
width: SIZE,
|
|
height: SIZE,
|
|
bitDepth: 8, // 8 red + 8 green + 8 blue + 8 alpha
|
|
colorType: 6, // RGBA
|
|
inputColorType: 6, // RGBA
|
|
inputHasAlpha: true,
|
|
})
|
|
png.data = Buffer.from(rendered)
|
|
// The transform stream is necessary because PNG requires me to pipe it somewhere before this event loop ends
|
|
const resultStream = png.pack()
|
|
const p = new stream.PassThrough()
|
|
resultStream.pipe(p)
|
|
return p
|
|
}
|
|
|
|
module.exports.convert = convert
|
|
module.exports.SIZE = SIZE
|