TelegramPWA/src/hooks/useOffscreenCanvasBlur.ts

37 lines
1.1 KiB
TypeScript

import { useLayoutEffect, useMemo, useRef } from '../lib/teact/teact';
import cycleRestrict from '../util/cycleRestrict';
import { MAX_WORKERS, requestMediaWorker } from '../util/launchMediaWorkers';
const RADIUS = 7;
let lastWorkerIndex = -1;
export default function useOffscreenCanvasBlur(
thumbData?: string, // data URI or blob URL
isDisabled = false,
radius = RADIUS,
) {
// eslint-disable-next-line no-null/no-null
const canvasRef = useRef<HTMLCanvasElement>(null);
const workerIndex = useMemo(() => cycleRestrict(MAX_WORKERS, ++lastWorkerIndex), []);
const offscreenRef = useRef<OffscreenCanvas>();
useLayoutEffect(() => {
if (!thumbData || isDisabled || offscreenRef.current) return;
const canvas = canvasRef.current;
if (!canvas) return;
offscreenRef.current = canvas.transferControlToOffscreen();
requestMediaWorker({
name: 'offscreen-canvas:blurThumb',
args: [offscreenRef.current, thumbData, radius],
transferables: [offscreenRef.current],
}, workerIndex);
}, [thumbData, isDisabled, radius, workerIndex]);
return canvasRef;
}