59 lines
1.5 KiB
TypeScript
59 lines
1.5 KiB
TypeScript
import { decode } from 'blurhash';
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import React, { useRef, useEffect } from 'react';
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interface IBlurhash {
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/** Hash to render */
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hash: string | null | undefined
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/** Width of the blurred region in pixels. Defaults to 32. */
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width?: number
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/** Height of the blurred region in pixels. Defaults to width. */
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height?: number
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/**
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* Whether dummy mode is enabled. If enabled, nothing is rendered
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* and canvas left untouched.
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*/
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dummy?: boolean
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/** className of the canvas element. */
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className?: string
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}
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/**
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* Renders a blurhash in a canvas element.
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* @see {@link https://blurha.sh/}
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*/
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const Blurhash: React.FC<IBlurhash> = ({
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hash,
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width = 32,
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height = width,
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dummy = false,
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...canvasProps
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}) => {
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const canvasRef = useRef<HTMLCanvasElement>(null);
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useEffect(() => {
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const { current: canvas } = canvasRef;
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if (!canvas) return;
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// resets canvas
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canvas.width = canvas.width; // eslint-disable-line no-self-assign
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if (dummy || !hash) return;
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try {
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const pixels = decode(hash, width, height);
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const ctx = canvas.getContext('2d');
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const imageData = new ImageData(pixels, width, height);
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if (!ctx) return;
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ctx.putImageData(imageData, 0, 0);
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} catch (err) {
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console.error('Blurhash decoding failure', { err, hash });
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}
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}, [dummy, hash, width, height]);
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return (
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<canvas {...canvasProps} ref={canvasRef} width={width} height={height} />
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);
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};
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export default React.memo(Blurhash);
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