speice.io/posts/2023/06/flam3/0-canvas.tsx
2023-07-15 22:48:06 +00:00

32 lines
752 B
TypeScript

import React, { useEffect, useRef } from "react";
import { renderFn } from "./0-utility";
export const Canvas: React.FC<{ f: renderFn }> = ({ f }) => {
const canvasRef = useRef<HTMLCanvasElement | null>(null);
let image: ImageData | null = null;
useEffect(() => {
if (canvasRef.current) {
const canvas = canvasRef.current;
const ctx = canvas.getContext("2d");
if (!ctx) {
return;
}
if (
!image ||
image.width !== canvas.width ||
image.height !== canvas.height
) {
image = ctx.createImageData(canvas.width, canvas.height);
}
f(image);
ctx.putImageData(image, 0, 0);
}
});
return <canvas ref={canvasRef} width={400} height={400} />;
};