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React component is duplicated with p5.js canvas

I'm trying to create a React app with a single p5.js sketch. However, the component containing the p5 sketch is being duplicated on my page. Not sure why it would be rendered this way.

Here you can see the code: https://stackblitz.com/edit/react-ts-kocwqw?file=App.tsx,Sketch.tsx,index.tsx

enter image description here

Here are the react components definition:

App.tsx

import React = require('react');
import Sketch from './Sketch';

function App() {
  return (
    <div className="App">
      <Sketch />
    </div>
  );
}

export default App;

Sketch.tsx

import React = require('react');
import { useEffect } from 'react';
import p5 from 'p5';

const Sketch = () => {
  const p = (p5: any) => {
    let radius: number;
    p5.setup = () => {
      p5.createCanvas(p5.windowWidth / 2, p5.windowHeight / 2);
      p5.background(0);
      radius = 0;
    };

    p5.draw = () => {
      p5.ellipse(p5.width / 2, p5.height / 2, radius, radius);
      if (radius < 70) radius++;
    };
  };

  useEffect(() => {
    new p5(p);
  }, []);

  return <></>;
};

export default Sketch;

index.tsx

import * as React from 'react';
import { StrictMode } from 'react';
import { createRoot } from 'react-dom/client';

import App from './App';

const rootElement = document.getElementById('root');
const root = createRoot(rootElement);

root.render(
  <StrictMode>
    <App />
  </StrictMode>
);

What could I be missing here?

about 4 years ago · Juan Pablo Isaza
1 answers
Answer question

0

Solution was to remove <StrictMode> from index.tsx.

From the docs,

Strict mode can’t automatically detect side effects for you, but it can help you spot them by making them a little more deterministic. This is done by intentionally double-invoking...

Looks like Strict Mode is a safeguard to detect side effects.

about 4 years ago · Juan Pablo Isaza Report
Answer question
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