Coding the stars - an interactive constellation with Three.js and React Three Fiber

04 Aug 2023

16 minute read

Every Launch Week is an opportunity for Supabase to experiment, try some spicy new designs, and dogfood our own technology. During our previous Launch Week we took Generative AI for a spin. This time we decided to shoot for the stars.

For Launch Week 8, we wanted to make the user-generated tickets a central piece of the launch week theme. To do this, we built a “constellation” of stars - an animated night sky where every user signup was represented as a star, in the form of an “8” shape.

We could approach this animation in a few ways.

For example, animating the stroke-dashoffset on an SVG path, similar to this example, was a good option, but it would have been difficult to randomize and change the shape at a later stage. Other approaches included 2D animation libraries, like Framer Motion , gsap or PixiJS .

Ultimately we decided to take Three.js for a spin using React Three Fiber (R3F) giving us a more powerful toolset to enable us to achieve the best possible result.

Learning Three.js is not a walk in the park but R3F abstracted many of its complexities such as cameras and renderers, to name a few. If you're new to R3F, some of the core primitives they provide for a basic scene include:

  • Geometries: used to create and define shapes
  • Materials: manage the texture and color of objects
  • Mesh: used to instantiate polygonal objects by combining a Geometry with a Material
  • Lights: to shine bright like a diamond 💎🎵
  • Canvas: where you define your R3F Scene

If you want to dive a little deeper, here are a few good resources we found to get a solid grasp on the topic:

Setting up the scene

In this article, we’re going to break down the steps to reproduce the Launch Week 8 animation using React Three Fiber in NextJs.

These are the dependencies we’ll need:


_10
npm install three @react-three/fiber

If you’re using React 17, we’ll spare you the trouble of finding the last compatible R3F version:


_10
npm install three @react-three/[email protected]

All we need for each particle is a circle geometry with a minimal amount of sides to minimize complexity.


_10
import { useMemo } from 'react'
_10
_10
const Geometry = useMemo(() => () => <circleGeometry args={[1.5, 5]} />, [])

A basic standard material with a white color will do just fine. Using the AdditiveBlending module from three provides a more interesting touch when particles happen to overlap, making them shine brighter:


_10
import { AdditiveBlending } from 'three'
_10
_10
const Material = () =>
_10
useMemo(() => <meshStandardMaterial color="#ffffff" blending={AdditiveBlending} />, [])

Let’s put it together in an R3F Canvas element and wrap up the initial setup with an ambientLight, which will make objects visible, just as real light does:


_40
import { useMemo } from 'react'
_40
import { Canvas } from '@react-three/fiber'
_40
import { AdditiveBlending } from 'three'
_40
_40
const Geometry = useMemo(
_40
() => () => <circleGeometry args={[1.5, 5]} />,
_40
[]
_40
)
_40
_40
const Material = () =>
_40
useMemo(
_40
() => (
_40
<meshStandardMaterial
_40
color="#ffffff"
_40
blending={AdditiveBlending}
_40
/>
_40
),
_40
[]
_40
)
_40
_40
return (
_40
<div style={{ width: 100vw, height: 100vh, background: "#000000" }}>
_40
<Canvas
_40
dpr={[1, 2]}
_40
camera={{ fov: 75, position: [0, 0, 500] }}
_40
>
_40
<ambientLight intensity={0.3} />
_40
<group>
_40
{particles?.map((particle, index) => (
_40
<mesh
_40
key={particle.username}
_40
>
_40
<Geometry />
_40
<Material />
_40
</mesh>
_40
))}
_40
</group>
_40
</Canvas>
_40
</div>
_40
)

For more context, the dpr values help with pixelation issues and the camera [0, 0, 500] position means that the camera is moved 500 units back in the z-axis to actually see the center [0,0,0] of the scene.

One thing to note is that the R3F Canvas renders a transparent background, so in order to see the white particle, we need to set the background of the parent html element to a dark color.

We created a separate component for the Particle, which will later encapsulate the animation logic.


_10
import React, { useRef } from 'react'
_10
_10
const Particle = ({ children }) => {
_10
const particle = useRef(null)
_10
_10
return <mesh ref={particle}>{children}</mesh>
_10
}
_10
_10
export default Particle

Load users from Supabase

You might have noticed we haven’t instantiated the particles yet. As we mentioned earlier, we wanted each particle to represent a ticket generated by a user and stored in the database. Let’s fetch the signups from the tickets table in our Supabase project (you might need to start your own Launch Week to fill your table):


_10
const [particles, setParticles] = useState([])
_10
_10
const loadUsers = async () => {
_10
return await supabase.from('lw8_tickets').select('*')
_10
}
_10
_10
useEffect(() => {
_10
const { data: users } = loadUsers()
_10
setParticles(users)
_10
}, [])

We updated the constellation in realtime whenever a new ticket was generated, but we’ll skip over this part to keep the article shorter. Since it’s all open-source, you can dive deeper here if you wish.

Animating the particles

To move the particle around the screen we are going to leverage a few different concepts: useFrame and trigonometry 🤯

useFrame

Generally, the most optimal way to animate things in a browser viewport, using javascript, is by leveraging a method called requestAnimationFrame , which “tells the browser that you wish to perform an animation and requests that the browser calls a specified function to update an animation right before the next repaint.”. R3F has a similar hook called useFrame that lets you execute code on every frame of Fiber's render loop. We’ll use this to change the position of the particles over time in a few moments.

Using time as an animation variable

We can extract time information from the useFrame clock parameter, to know how much time has elapsed in our application, and use that time to animate a value. Updating the x position with Math.sin() generates a horizontal oscillating movement. Multiply it with a widthRadius variable to customize the amplitude of the movement.


_13
const particle = useRef(null)
_13
_13
const widthRadius = 100
_13
const heightRadius = 100
_13
_13
useFrame(({ clock }) => {
_13
const timer = clock.getElapsedTime()
_13
_13
particle.current.position.x = Math.sin(timer) * widthRadius
_13
}
_13
})
_13
_13
return <mesh ref={particle}>{children}</mesh>

Combine the previous horizontal movement with a Math.cos() on the y position to draw a circle:


_10
particle.current.position.y = Math.cos(timer) * heightRadius

Calculating the circumference we can get the time the x position takes to complete a full circle.


_10
const circumference = (config.widthRadius * Math.PI * 2) / 100

When that happens, we can invert the cos sign on every other loop to obtain a basic 8 shape.


_10
const isEven = Math.floor(timer / circumference) % 2 == 0
_10
_10
particle.current.position.x = Math.sin(timer) * widthRadius
_10
particle.current.position.y = isEven
_10
? Math.cos(timer) * heightRadius - heightRadius
_10
: -Math.cos(timer) * heightRadius + heightRadius

At this point, we played around with a number of parameters that made the animation more randomized and interesting.

For example, we randomized the speed and the delay of each particle:


_10
const minSpeed = -0.3
_10
const maxSpeed = 0.4
_10
const speed = Math.random() * (minSpeed - maxSpeed) + maxSpeed
_10
_10
const delayOffsetFactor = 100
_10
const delayOffset = Math.random() * delayOffsetFactor
_10
_10
[...]
_10
_10
const timer = clock.getElapsedTime() *** speed + delayOffset**

We offset the shape on the x-axis, to concentrate most of the particles in the core of the 8 shape and leave a smaller amount externally, by playing around with exponentials using Math.pow() in combination with some more randomization.


_13
const xThickness = 7
_13
const xRandomnessShape = 2.2
_13
const xRandomness = 5
_13
_13
const pathOffset =
_13
Math.pow(
_13
Math.random() * xRandomnessShape,
_13
xRandomness - xRandomness / 2
_13
) * xThickness
_13
_13
...
_13
_13
particle.current.position.x = Math.sin(timer) * widthRadius + pathOffset

Honestly, this was the result of a lot of playing and tweaking around, and we certainly didn’t hit the best possible result on the first try. Perhaps you want to take some time to experiment with the math - you might find even better and more configurable results.

GUI playground

What really helped to visualize the shape, gather feedback, and decide on a final design was adding a GUI to play around with the values. You can try for yourself by appending #debug to the supabase.com/launch-week#debug url. Go crazy with it.

We used the dat.gui library:


_10
npm install [email protected]

Which needs to be loaded asynchronously, otherwise it raises a window is not defined error.


_10
const init = async () => {
_10
const dat = await import('dat.gui')
_10
const gui = new dat.GUI()
_10
}
_10
_10
useEffect(() => {
_10
init()
_10
}, [])

Then we prepared a useParticlesConfig hook with all the configuration wired up to the GUI. Whenever the GUI updated, we also updated react state.


_66
import { useEffect, useState } from 'react'
_66
import { range } from 'lodash'
_66
_66
let defaultConfig = {
_66
particles: 1500,
_66
widthRadius: 100,
_66
topHeightRadius: 80,
_66
bottomHeightRadius: 100,
_66
xThickness: 7,
_66
xRandomnessFactor: 2.2,
_66
xRandomnessShape: 2.2,
_66
xRandomness: 5,
_66
yThickness: 20,
_66
max_speed: 0.1,
_66
min_speed: -0.1,
_66
}
_66
_66
const useParticlesConfig = (): any => {
_66
if (typeof window === 'undefined') return null
_66
const hash = window.location.hash
_66
const isDebugMode = hash.includes('#debug')
_66
const [particles, setParticles] = useState(range(0, defaultConfig.particles))
_66
_66
const [config, setConfig] = useState(defaultConfig)
_66
_66
const handleSetConfig = (name, value) => {
_66
setConfig((prevConfig) => ({ ...prevConfig, [name]: value }))
_66
}
_66
_66
const init = async () => {
_66
if (!isDebugMode) return
_66
const dat = await import('dat.gui')
_66
const gui = new dat.GUI()
_66
const particlesFolder = gui.addFolder('Particles')
_66
const shapeFolder = gui.addFolder('Shape')
_66
_66
particlesFolder
_66
.add(config, 'particles')
_66
.min(1)
_66
.max(5000)
_66
.step(1)
_66
.onChange((value) => {
_66
handleSetConfig('particles', value)
_66
setParticles(range(0, value))
_66
})
_66
shapeFolder
_66
.add(config, 'widthRadius')
_66
.min(1)
_66
.max(200)
_66
.step(1)
_66
.onChange((value) => handleSetConfig('widthRadius', value))
_66
_66
// add desired folders and parameters
_66
_66
particlesFolder.open()
_66
shapeFolder.open()
_66
}
_66
_66
useEffect(() => {
_66
init()
_66
}, [])
_66
_66
return { config, handleSetConfig, particles, setParticles, isDebugMode }
_66
}
_66
_66
export default useParticlesConfig

Here is the final code:


_84
import React, { useMemo, useEffect, useState } from 'react'
_84
import { Canvas, useFrame } from '@react-three/fiber'
_84
import { AdditiveBlending } from 'three'
_84
import useParticlesConfig from './hooks/useParticlesConfig'
_84
_84
const ParticlesCanvas = () => {
_84
if (typeof window === 'undefined') return null
_84
const { config, particles } = useParticlesConfig()
_84
_84
const Geometry = useMemo(
_84
() => () => <circleGeometry args={[config.particlesSize, config.particlesSides]} />,
_84
[]
_84
)
_84
_84
const Material = () =>
_84
useMemo(
_84
() => (
_84
<meshStandardMaterial
_84
color={config.color}
_84
blending={config.particlesBlending ? AdditiveBlending : undefined}
_84
/>
_84
),
_84
[]
_84
)
_84
_84
return (
_84
<div style={{ width: 100vw, height: 100vh, background: "#000000" }}>
_84
<Canvas
_84
dpr={[1, 2]}
_84
camera={{ fov: 75, position: [0, 0, 500] }}
_84
>
_84
<ambientLight intensity={config.lightIntensity} />
_84
<group>
_84
{particles?.map((particle, index) => (
_84
<Particle
_84
key={particle.username}
_84
>
_84
<Geometry />
_84
<Material />
_84
</Particle>
_84
))}
_84
</group>
_84
</Canvas>
_84
</div>
_84
)
_84
}
_84
_84
const Particle = ({ children }: Props) => {
_84
const particle = useRef(null)
_84
_84
const pathOffset =
_84
Math.pow(
_84
Math.random() * config.xRandomnessShape,
_84
config.xRandomness - config.xRandomness / 2
_84
) * config.xThickness
_84
_84
const verticalRandomness = Math.random() * (config.yThickness - 1) + 1 - config.yThickness / 2
_84
_84
const speed = Math.random() * (config.min_speed - config.max_speed) + config.max_speed
_84
_84
const circumference = (config.widthRadius * Math.PI * 2) / 100
_84
const delayOffsetFactor = 100
_84
const delayOffset = Math.random() * delayOffsetFactor
_84
_84
useFrame(({ clock }) => {
_84
const timer = clock.getElapsedTime() * speed + delayOffset
_84
const isEven = Math.floor(timer / circumference) % 2 == 0
_84
_84
// When the loop count is even, draw bottom 8 shape
_84
// if odd, draw top 8 shape
_84
particle.current.position.x = isEven
_84
? Math.sin(timer) * config.widthRadius * config.widthRatio + pathOffset
_84
: Math.sin(timer) * config.widthRadius + pathOffset
_84
particle.current.position.y = isEven
_84
? Math.cos(timer) * config.bottomHeightRadius -
_84
config.bottomHeightRadius +
_84
verticalRandomness
_84
: -Math.cos(timer) * config.topHeightRadius + config.topHeightRadius + verticalRandomness
_84
})
_84
_84
return <mesh ref={particle}>{children}</mesh>
_84
}
_84
_84
export default Particle

Now THAT’S how you create a new constellation ✨. Feel free to use the code and learnings to build your own.

Conclusion

In this journey, you saw how to use Three.js and harness the power of React Three Fiber and creative experimentation to craft an animation. We leveraged trigonometry, animation hooks, and GUI playgrounds to build a "8" shape formed by user-generated stars.

If you loved this and the new Launch Week 8 branding, make sure to tune in on Monday at 09 AM PT as we unveil the full landing 💥

More Supabase Design

Share this article

Build in a weekend, scale to millions