Testing hot-swapping renderers, which requires destroying and rebuilding the canvas after all. Fixed a few other related bugs and moved the imports into "bundle-contents.js".

js/Matrix.js

@@ -1,13 +1,6 @@
-import inclusions from "./inclusions";
-
 import React, { useEffect, useState, useRef, memo } from "react";
-import * as reglRenderer from "./regl/main";
-import * as webgpuRenderer from "./webgpu/main";
 import makeConfig from "./utils/config";
 
-globalThis.inclusions = inclusions;
-console.log(webgpuRenderer.init, webgpuRenderer.formulate, webgpuRenderer.destroy);
-
 /**
  * @typedef {object} Colour
  * @property {"hsl"|"rgb"} space
@@ -115,33 +108,64 @@ export const Matrix = memo((props) => {
 	const { style, className, ...rest } = props;
 	const elProps = { style, className };
 	const matrix = useRef(null);
-	const [rain, setRain] = useState(null);
+	const [rCanvas, setCanvas] = useState(null);
+	const [rRenderer, setRenderer] = useState(null);
+	const [rRain, setRain] = useState(null);
+
+	const supportsWebGPU = () => {
+		return (
+			window.GPUQueue != null &&
+			navigator.gpu != null &&
+			navigator.gpu.getPreferredCanvasFormat != null
+		);
+	};
 
 	useEffect(() => {
+		const useWebGPU = supportsWebGPU() && ["webgpu"].includes(rest.renderer?.toLowerCase());
+		const isWebGPU = rRenderer?.type === "webgpu";
+
+		if (rRenderer != null && useWebGPU === isWebGPU) {
+			return;
+		}
+
+		if (rCanvas != null) {
+			matrix.current.removeChild(rCanvas);
+			setCanvas(null);
+		}
+
+		if (rRain != null) {
+			rRenderer?.destroy(rRain);
+			setRain(null);
+		}
+
+		if (rRenderer != null) {
+			setRenderer(null);
+		}
+
 		const canvas = document.createElement("canvas");
-		matrix.current.appendChild(canvas);
 		canvas.style.width = "100%";
 		canvas.style.height = "100%";
-		const init = async () => {
+		matrix.current.appendChild(canvas);
-			setRain(await reglRenderer.init(canvas));
+		setCanvas(canvas);
-		};
-		init();
 
-		return () => {
+		const loadRain = async () => {
-			reglRenderer.destroy(rain);
+			const renderer = await import(`./${useWebGPU ? "webgpu" : "regl"}/main.js`);
-			setRain(null);
+			setRenderer(renderer);
+			const rain = await renderer.init(canvas);
+			setRain(rain);
 		};
-	}, []);
+		loadRain();
+	}, [props.renderer]);
 
 	useEffect(() => {
-		if (rain == null) {
+		if (rRain == null || rRain.destroyed) {
 			return;
 		}
 		const refresh = async () => {
-			await reglRenderer.formulate(rain, makeConfig({ ...rest }));
+			await rRenderer.formulate(rRain, makeConfig({ ...rest }));
 		};
 		refresh();
-	}, [props, rain]);
+	}, [props, rRain]);
 
 	return <div ref={matrix} {...elProps}></div>;
 });

js/bundle-contents.js

@@ -0,0 +1,8 @@
+import { Matrix } from "./Matrix";
+import inclusions from "./inclusions";
+import * as reglRenderer from "./regl/main";
+import * as webgpuRenderer from "./webgpu/main";
+globalThis.inclusions = inclusions;
+globalThis.reglRenderer = reglRenderer;
+globalThis.webgpuRenderer = webgpuRenderer;
+globalThis.Matrix = Matrix;

js/index.js

@@ -1,7 +1,6 @@
 import React from "react";
 import { createRoot } from "react-dom/client";
 import { Matrix } from "./Matrix";
-//import { Matrix } from "react-matrix-rain";
 
 const root = createRoot(document.getElementById("root"));
 let idx = 1;
@@ -23,6 +22,7 @@ const versions = [
 const App = () => {
 	const [version, setVersion] = React.useState(versions[0]);
 	const [numColumns, setNumColumns] = React.useState(10);
+	const [rendererType, setRendererType] = React.useState(null);
 	const onButtonClick = () => {
 		setVersion((s) => {
 			const newVersion = versions[idx];
@@ -36,16 +36,20 @@ const App = () => {
 			return newColumns;
 		});
 	};
+	const onRendererButtonClick = () => {
+		setRendererType(() => (rendererType === "webgpu" ? "regl" : "webgpu"));
+	};
 
 	return (
 		<div>
 			<h1>Rain</h1>
-			<button onClick={onButtonClick}>Change</button>
+			<button onClick={onButtonClick}>Change properties</button>
-			{/* <button onClick={newNum}>change number</button> */}
+			<button onClick={onRendererButtonClick}>Renderer: {rendererType ?? "default (regl)"}</button>
 			<Matrix
 				style={{ width: "80vw", height: "45vh" }}
 				version={version}
 				numColumns={numColumns}
+				renderer={rendererType}
 				density={2.0}
 			/>
 		</div>

js/regl/main.js

@@ -69,6 +69,9 @@ export const init = async (canvas) => {
 };
 
 export const formulate = async (rain, config) => {
+	if (rain.destroyed) {
+		throw new Error("Cannot formulate a destroyed rain instance.");
+	}
 	const { resize, canvas, cache, regl } = rain;
 	rain.resolution = config.resolution;
 	resize();
@@ -150,10 +153,17 @@ export const formulate = async (rain, config) => {
 	rain.tick = tick;
 };
 
-export const destroy = ({ regl, cache, resize, doubleClick, tick, canvas }) => {
+export const destroy = (rain) => {
+	if (rain.destroyed) {
+		return;
+	}
+	const { regl, cache, resize, doubleClick, tick, canvas } = rain;
 	window.removeEventListener("resize", resize);
 	window.removeEventListener("dblclick", doubleClick);
 	cache.clear();
 	tick.cancel(); // stop RAF
 	regl.destroy(); // release all GPU resources & event listeners
+	rain.destroyed = true;
 };
+
+export const type = "regl";

js/webgpu/main.js

@@ -75,6 +75,9 @@ export const init = async (canvas) => {
 };
 
 export const formulate = async (rain, config) => {
+	if (rain.destroyed) {
+		throw new Error("Cannot formulate a destroyed rain instance.");
+	}
 	const { resize, canvas, cache, canvasContext, adapter, device } = rain;
 	rain.resolution = config.resolution;
 	resize();
@@ -197,10 +200,18 @@ export const formulate = async (rain, config) => {
 	rain.renderLoop = renderLoop;
 };
 
-export const destroy = ({ device, resize, doubleClick, cache, canvas }) => {
+export const destroy = (rain) => {
+	if (rain.destroyed) {
+		return;
+	}
+	const { device, resize, doubleClick, cache, canvas, renderLoop } = rain;
 	window.removeEventListener("resize", resize);
 	window.removeEventListener("dblclick", doubleClick);
 	cache.clear();
-	tick.cancel(); // stop RAF
+	cancelAnimationFrame(renderLoop); // stop RAF
 	// TODO: destroy WebGPU resources
+	device.destroy();
+	rain.destroyed = true;
 };
+
+export const type = "webgpu";

js/webgpu/rainPass.js

@@ -29,7 +29,6 @@ const makeConfigBuffer = (device, configUniforms, config, density, gridSize, gly
 	};
 	// console.table(configData);
 
-	console.log(configUniforms, configData);
 	return makeUniformBuffer(device, configUniforms, configData);
 };
 

rollup.config.mjs

@@ -9,7 +9,7 @@ import { string } from "rollup-plugin-string";
 import image from "@rollup/plugin-image";
 
 export default {
-	input: "js/Matrix.js",
+	input: "js/bundle-contents.js",
 	external: ["react", "react-dom"], // keep them out of your bundle
 	plugins: [
 		peerDepsExternal(), // auto-exclude peerDeps