speice.io/posts/2023/06/flam3/0-canvas.tsx
2023-07-17 02:47:53 +00:00

72 lines
1.7 KiB
TypeScript

import React, { useEffect, useRef } from "react";
import { Renderer, 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} />;
};
export type CanvasParams = {
defaultUrl: string;
size: number;
qualityMax: number;
qualityStep: number;
renderer: Renderer;
};
export const CanvasRenderer: React.FC<{ params: CanvasParams }> = ({
params,
}) => {
const canvasRef = useRef<HTMLCanvasElement | null>(null);
var qualityCurrent: number = 0;
const animate = () => {
const ctx = canvasRef.current?.getContext("2d");
if (!ctx) {
return;
}
const image = ctx.createImageData(params.size, params.size);
params.renderer.run(params.qualityStep);
params.renderer.render(image);
ctx.putImageData(image, 0, 0);
qualityCurrent += params.qualityStep;
if (qualityCurrent < params.qualityMax) {
requestAnimationFrame(animate);
}
};
useEffect(() => {
if (canvasRef.current) {
requestAnimationFrame(animate);
}
}, []);
return <canvas ref={canvasRef} width={params.size} height={params.size} />;
};