react-three-fiber

react-three-fiber is a React renderer for threejs.

npm install three @react-three/fiber

Why?

Build your scene declaratively with re-usable, self-contained components that react to state, are readily interactive and can tap into React's ecosystem.

Does it have limitations?

None. Everything that works in threejs will work here without exception.

Can it keep up with frequent updates to threejs?

Yes, because it merely expresses threejs in JSX: <mesh /> becomes new THREE.Mesh(), and that happens dynamically. There is no hard dependency on a particular threejs version, it does not wrap or duplicate a single threejs class.

Is it slower than plain threejs?

There is no additional overhead. Components participate in the renderloop outside of React.

What does it look like?

Let's make a re-usable component that has its own state, reacts to user-input and participates in the render-loop. (live demo).

import ReactDOM from 'react-dom'
import React, { useRef, useState } from 'react'
import { Canvas, useFrame } from '@react-three/fiber'

function Box(props) {
  // This reference will give us direct access to the mesh
  const mesh = useRef()
  // Set up state for the hovered and active state
  const [hovered, setHover] = useState(false)
  const [active, setActive] = useState(false)
  // Rotate mesh every frame, this is outside of React without overhead
  useFrame((state, delta) => (mesh.current.rotation.x += 0.01))
  // Return view, these are regular threejs elements expressed in JSX
  return (
    <mesh
      {...props}
      ref={mesh}
      scale={active ? 1.5 : 1}
      onClick={(event) => setActive(!active)}
      onPointerOver={(event) => setHover(true)}
      onPointerOut={(event) => setHover(false)}>
      <boxGeometry args={[1, 1, 1]} />
      <meshStandardMaterial color={hovered ? 'hotpink' : 'orange'} />
    </mesh>
  )
}

ReactDOM.render(
  <Canvas>
    <ambientLight />
    <pointLight position={[10, 10, 10]} />
    <Box position={[-1.2, 0, 0]} />
    <Box position={[1.2, 0, 0]} />
  </Canvas>,
  document.getElementById('root'),
)

Show TypeScript example

npm install @types/three

import * as THREE from 'three'
import ReactDOM from 'react-dom'
import React, { useRef, useState } from 'react'
import { Canvas, useFrame } from '@react-three/fiber'

function Box(props: JSX.IntrinsicElements['mesh']) {
  const mesh = useRef<THREE.Mesh>(null!)
  const [hovered, setHover] = useState(false)
  const [active, setActive] = useState(false)
  useFrame((state, delta) => (mesh.current.rotation.x += 0.01))
  return (
    <mesh
      {...props}
      ref={mesh}
      scale={active ? 1.5 : 1}
      onClick={(event) => setActive(!active)}
      onPointerOver={(event) => setHover(true)}
      onPointerOut={(event) => setHover(false)}>
      <boxGeometry args={[1, 1, 1]} />
      <meshStandardMaterial color={hovered ? 'hotpink' : 'orange'} />
    </mesh>
  )
}

ReactDOM.render(
  <Canvas>
    <ambientLight />
    <pointLight position={[10, 10, 10]} />
    <Box position={[-1.2, 0, 0]} />
    <Box position={[1.2, 0, 0]} />
  </Canvas>,
  document.getElementById('root'),
)

Live demo: https://codesandbox.io/s/icy-tree-brnsm?file=/src/App.tsx

Documentation

Fundamentals

You need to be versed in both React and Threejs before rushing into this. If you are unsure about React consult the official React docs, especially the section about hooks. As for Threejs, make sure you at least glance over the following links:

Make sure you have a basic grasp of Threejs. Keep that site open.
When you know what a scene is, a camera, mesh, geometry, material, fork the demo above.
Look up the JSX elements that you see (mesh, ambientLight, etc), all threejs exports are native to three-fiber.
Try changing some values, scroll though our Api to see what the various settings and hooks do.

Some reading material:

Threejs-docs
Threejs-examples
Threejs-fundamentals
Discover Threejs
Do's and don'ts for performance and best practices
react-three-fiber alligator.io tutorial by @dghez_

Ecosystem

@react-three/gltfjsx – turns GLTFs into JSX components
@react-three/drei – useful helpers for react-three-fiber
@react-three/postprocessing – post-processing effects
@react-three/flex – flexbox for react-three-fiber
@react-three/xr – VR/AR controllers and events
@react-three/cannon – physics based hooks
zustand – state management
react-spring – a spring-physics-based animation library
react-use-gesture – mouse/touch gestures

How to contribute

If you like this project, please consider helping out. All contributions are welcome as well as donations to Opencollective, or in crypto BTC: 36fuguTPxGCNnYZSRdgdh6Ea94brCAjMbH, ETH: 0x6E3f79Ea1d0dcedeb33D3fC6c34d2B1f156F2682.

Backers

Thank you to all our backers! 🙏

Contributors

This project exists thanks to all the people who contribute.

AlexandreBonaventure/react-three-fiber