Web3d Integration Patterns

├── 3D Layer (Three.js)
│   ├── Scene management
│   ├── Camera controls
│   └── Render loop
├── Animation Layer (GSAP)
│   ├── ScrollTrigger for 3D properties
│   ├── Timelines for sequences
│   └── UI transitions
└── UI Layer (React + Motion)
    ├── HTML overlays
    ├── State management
    └── User interactions

// App.jsx - React root
import { useEffect, useRef } from 'react'
import { initThreeScene } from './three/scene'
import { initScrollAnimations } from './animations/scroll'
import { motion } from 'framer-motion'

function App() {
  const canvasRef = useRef()
  const sceneRef = useRef()

  useEffect(() => {
    // Initialize Three.js scene
    sceneRef.current = initThreeScene(canvasRef.current)

    // Initialize GSAP ScrollTrigger animations
    initScrollAnimations(sceneRef.current)

    // Cleanup
    return () => {
      sceneRef.current.dispose()
    }
  }, [])

  return (
    <div className="app">
      <canvas ref={canvasRef} />

      <motion.div
        className="overlay"
        initial={{ opacity: 0 }}
        animate={{ opacity: 1 }}
      >
        <section className="hero">
          <h1>3D Experience</h1>
        </section>
        <section className="content">
          {/* Scrollable content */}
        </section>
      </motion.div>
    </div>
  )
}

// three/scene.js - Three.js setup
import * as THREE from 'three'
import { OrbitControls } from 'three/addons/controls/OrbitControls.js'

export function initThreeScene(canvas) {
  const scene = new THREE.Scene()
  const camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000)
  const renderer = new THREE.WebGLRenderer({ canvas, antialias: true, alpha: true })

  renderer.setSize(window.innerWidth, window.innerHeight)
  renderer.setPixelRatio(Math.min(window.devicePixelRatio, 2))

  const controls = new OrbitControls(camera, canvas)
  controls.enableDamping = true

  // Setup scene objects
  const geometry = new THREE.BoxGeometry(2, 2, 2)
  const material = new THREE.MeshStandardMaterial({ color: 0x00ff00 })
  const cube = new THREE.Mesh(geometry, material)
  scene.add(cube)

  // Lighting
  const ambientLight = new THREE.AmbientLight(0xffffff, 0.5)
  scene.add(ambientLight)

  const directionalLight = new THREE.DirectionalLight(0xffffff, 1)
  directionalLight.position.set(5, 10, 7.5)
  scene.add(directionalLight)

  camera.position.set(0, 2, 5)

  // Animation loop
  function animate() {
    requestAnimationFrame(animate)
    controls.update()
    renderer.render(scene, camera)
  }
  animate()

  // Resize handler
  window.addEventListener('resize', () => {
    camera.aspect = window.innerWidth / window.innerHeight
    camera.updateProjectionMatrix()
    renderer.setSize(window.innerWidth, window.innerHeight)
  })

  return { scene, camera, renderer, cube }
}

// animations/scroll.js - GSAP ScrollTrigger integration
import gsap from 'gsap'
import { ScrollTrigger } from 'gsap/ScrollTrigger'

gsap.registerPlugin(ScrollTrigger)

export function initScrollAnimations(sceneRefs) {
  const { camera, cube } = sceneRefs

  // Animate camera on scroll
  gsap.to(camera.position, {
    x: 5,
    y: 3,
    z: 10,
    scrollTrigger: {
      trigger: '.content',
      start: 'top top',
      end: 'bottom center',
      scrub: 1,
      onUpdate: () => camera.lookAt(cube.position)
    }
  })

  // Animate mesh rotation
  gsap.to(cube.rotation, {
    y: Math.PI * 2,
    x: Math.PI,
    scrollTrigger: {
      trigger: '.content',
      start: 'top bottom',
      end: 'bottom top',
      scrub: true
    }
  })

  // Animate material properties
  gsap.to(cube.material, {
    opacity: 0.3,
    scrollTrigger: {
      trigger: '.content',
      start: 'top center',
      end: 'center center',
      scrub: 1
    }
  })
}

React Component Tree
├── <Canvas> (R3F)
│   ├── 3D Scene Components
│   ├── Lights
│   ├── Camera
│   └── Effects
└── <motion.div> (UI overlays)
    ├── HTML content
    └── Animations

// App.jsx - Unified React approach
import { Canvas } from '@react-three/fiber'
import { Suspense } from 'react'
import { motion } from 'framer-motion'
import { Scene } from './components/Scene'
import { Loader } from './components/Loader'

function App() {
  return (
    <div className="app">
      <Canvas
        camera={{ position: [0, 2, 5], fov: 75 }}
        dpr={[1, 2]}
        shadows
      >
        <Suspense fallback={<Loader />}>
          <Scene />
        </Suspense>
      </Canvas>

      <motion.div
        className="ui-overlay"
        initial={{ opacity: 0 }}
        animate={{ opacity: 1 }}
        transition={{ duration: 1 }}
      >
        <h1>React-First 3D Experience</h1>
      </motion.div>
    </div>
  )
}

// components/Scene.jsx - R3F scene
import { useRef, useState } from 'react'
import { useFrame } from '@react-three/fiber'
import { OrbitControls, Environment } from '@react-three/drei'
import { motion } from 'framer-motion-3d'

export function Scene() {
  return (
    <>
      <ambientLight intensity={0.5} />
      <directionalLight position={[5, 10, 7.5]} castShadow />

      <AnimatedCube />
      <Floor />

      <OrbitControls enableDamping dampingFactor={0.05} />
      <Environment preset="sunset" />
    </>
  )
}

function AnimatedCube() {
  const [hovered, setHovered] = useState(false)
  const [active, setActive] = useState(false)

  return (
    <motion.mesh
      scale={active ? 1.5 : 1}
      onClick={() => setActive(!active)}
      onPointerOver={() => setHovered(true)}
      onPointerOut={() => setHovered(false)}
      animate={{
        rotateY: hovered ? Math.PI * 2 : 0
      }}
      transition={{ type: 'spring', stiffness: 200, damping: 20 }}
    >
      <boxGeometry args={[2, 2, 2]} />
      <meshStandardMaterial color={hovered ? 'hotpink' : 'orange'} />
    </motion.mesh>
  )
}

function Floor() {
  return (
    <mesh rotation={[-Math.PI / 2, 0, 0]} position={[0, -1, 0]} receiveShadow>
      <planeGeometry args={[100, 100]} />
      <meshStandardMaterial color="#222" />
    </mesh>
  )
}

// components/AnimatedScene.jsx
import { useRef, useEffect } from 'react'
import { useFrame } from '@react-three/fiber'
import gsap from 'gsap'

export function AnimatedScene() {
  const groupRef = useRef()
  const timelineRef = useRef()

  useEffect(() => {
    // Create GSAP timeline for complex sequence
    const tl = gsap.timeline({ repeat: -1, yoyo: true })

    tl.to(groupRef.current.position, {
      y: 2,
      duration: 1,
      ease: 'power2.inOut'
    })
    .to(groupRef.current.rotation, {
      y: Math.PI * 2,
      duration: 2,
      ease: 'none'
    }, 0) // Start at same time

    timelineRef.current = tl

    return () => tl.kill()
  }, [])

  return (
    <group ref={groupRef}>
      <mesh>
        <boxGeometry />
        <meshStandardMaterial color="cyan" />
      </mesh>
    </group>
  )
}

// components/PhysicsCube.jsx
import { useRef } from 'react'
import { useFrame } from '@react-three/fiber'
import { useSpring, animated, config } from '@react-spring/three'

const AnimatedMesh = animated('mesh')

export function PhysicsCube() {
  const [springs, api] = useSpring(() => ({
    scale: 1,
    position: [0, 0, 0],
    config: config.wobbly
  }), [])

  const handleClick = () => {
    api.start({
      scale: 1.5,
      position: [0, 2, 0]
    })

    // Return to original after delay
    setTimeout(() => {
      api.start({
        scale: 1,
        position: [0, 0, 0]
      })
    }, 1000)
  }

  return (
    <AnimatedMesh
      scale={springs.scale}
      position={springs.position}
      onClick={handleClick}
    >
      <boxGeometry />
      <meshStandardMaterial color="orange" />
    </AnimatedMesh>
  )
}

import gsap from 'gsap'
import { ScrollTrigger } from 'gsap/ScrollTrigger'

gsap.registerPlugin(ScrollTrigger)

// Smooth camera path through multiple points
const cameraPath = [
  { x: 0, y: 2, z: 5, lookAt: { x: 0, y: 0, z: 0 } },
  { x: 5, y: 3, z: 10, lookAt: { x: 0, y: 0, z: 0 } },
  { x: -3, y: 1, z: 8, lookAt: { x: 0, y: 0, z: 0 } }
]

const tl = gsap.timeline({
  scrollTrigger: {
    trigger: '#container',
    start: 'top top',
    end: 'bottom bottom',
    scrub: 1,
    pin: true
  }
})

cameraPath.forEach((point, i) => {
  tl.to(camera.position, {
    x: point.x,
    y: point.y,
    z: point.z,
    duration: 1,
    onUpdate: () => camera.lookAt(point.lookAt.x, point.lookAt.y, point.lookAt.z)
  }, i)
})

import { ScrollControls, Scroll, useScroll } from '@react-three/drei'
import { useFrame } from '@react-three/fiber'

function CameraRig() {
  const scroll = useScroll()

  useFrame((state) => {
    const offset = scroll.offset

    state.camera.position.x = Math.sin(offset * Math.PI * 2) * 5
    state.camera.position.z = Math.cos(offset * Math.PI * 2) * 5
    state.camera.lookAt(0, 0, 0)
  })

  return null
}

export function App() {
  return (
    <Canvas>
      <ScrollControls pages={3} damping={0.5}>
        <CameraRig />
        <Scroll>
          <Scene />
        </Scroll>
      </ScrollControls>
    </Canvas>
  )
}

import { motion } from 'framer-motion-3d'

function DraggableObject() {
  return (
    <motion.mesh
      drag
      dragElastic={0.1}
      dragConstraints={{ left: -5, right: 5, top: 5, bottom: -5 }}
      whileHover={{ scale: 1.1 }}
      whileTap={{ scale: 0.9 }}
      animate={{
        rotateY: [0, Math.PI * 2],
        transition: { repeat: Infinity, duration: 4, ease: 'linear' }
      }}
    >
      <sphereGeometry args={[1, 32, 32]} />
      <meshStandardMaterial color="hotpink" />
    </motion.mesh>
  )
}

// store.js
import create from 'zustand'

export const useStore = create((set) => ({
  selectedObject: null,
  cameraMode: 'orbit',
  setSelectedObject: (obj) => set({ selectedObject: obj }),
  setCameraMode: (mode) => set({ cameraMode: mode })
}))

// components/InteractiveObject.jsx
import { useRef, useEffect } from 'react'
import { useStore } from '../store'
import gsap from 'gsap'

export function InteractiveObject({ id }) {
  const meshRef = useRef()
  const selectedObject = useStore((state) => state.selectedObject)
  const setSelectedObject = useStore((state) => state.setSelectedObject)

  const isSelected = selectedObject === id

  useEffect(() => {
    if (isSelected) {
      gsap.to(meshRef.current.scale, {
        x: 1.2,
        y: 1.2,
        z: 1.2,
        duration: 0.3,
        ease: 'back.out'
      })
      gsap.to(meshRef.current.material, {
        emissiveIntensity: 0.5,
        duration: 0.3
      })
    } else {
      gsap.to(meshRef.current.scale, {
        x: 1,
        y: 1,
        z: 1,
        duration: 0.3,
        ease: 'power2.inOut'
      })
      gsap.to(meshRef.current.material, {
        emissiveIntensity: 0,
        duration: 0.3
      })
    }
  }, [isSelected])

  return (
    <mesh
      ref={meshRef}
      onClick={() => setSelectedObject(isSelected ? null : id)}
    >
      <boxGeometry />
      <meshStandardMaterial color="cyan" emissive="cyan" />
    </mesh>
  )
}

// store/scene.js
import create from 'zustand'

export const useSceneStore = create((set, get) => ({
  // State
  camera: { position: [0, 2, 5], target: [0, 0, 0] },
  objects: {},
  selectedId: null,
  isAnimating: false,

  // Actions
  updateCamera: (updates) => set((state) => ({
    camera: { ...state.camera, ...updates }
  })),

  addObject: (id, object) => set((state) => ({
    objects: { ...state.objects, [id]: object }
  })),

  selectObject: (id) => set({ selectedId: id }),

  setAnimating: (isAnimating) => set({ isAnimating })
}))

import { useSceneStore } from '../store/scene'

function Object3D({ id }) {
  const selectedId = useSceneStore((state) => state.selectedId)
  const selectObject = useSceneStore((state) => state.selectObject)

  const isSelected = selectedId === id

  return (
    <mesh onClick={() => selectObject(id)}>
      <boxGeometry />
      <meshStandardMaterial color={isSelected ? 'hotpink' : 'orange'} />
    </mesh>
  )
}

// Unified render loop with conditional rendering
import { Clock } from 'three'

const clock = new Clock()
let needsRender = true

function animate() {
  requestAnimationFrame(animate)

  const delta = clock.getDelta()
  const elapsed = clock.getElapsedTime()

  // Only render when needed
  if (needsRender || controls.enabled) {
    // Update GSAP animations (handled automatically)

    // Update Three.js
    controls.update()
    renderer.render(scene, camera)

    // Reset flag
    needsRender = false
  }
}

// Trigger re-render on interactions
ScrollTrigger.addEventListener('update', () => {
  needsRender = true
})

import { Canvas } from '@react-three/fiber'

function App() {
  return (
    <Canvas
      frameloop="demand" // Only renders when needed
      dpr={[1, 2]} // Adaptive pixel ratio
    >
      <Scene />
    </Canvas>
  )
}

function Scene() {
  const invalidate = useThree((state) => state.invalidate)

  // Trigger render on state change
  const handleClick = () => {
    // Update state...
    invalidate() // Manually trigger render
  }

  return <mesh onClick={handleClick}>...</mesh>
}

// ❌ Wrong: GSAP and React Spring both animating position
gsap.to(meshRef.current.position, { x: 5 })
api.start({ position: [10, 0, 0] }) // Conflict!

// ✅ Correct: Separate properties
gsap.to(meshRef.current.position, { x: 5 }) // GSAP handles position
api.start({ scale: 1.5 }) // Spring handles scale

// ❌ Wrong: Updating Three.js without updating React state
mesh.position.x = 5 // Three.js updated
// But React state still shows old value!

// ✅ Correct: Update both
const updatePosition = (x) => {
  mesh.position.x = x
  setPosition(x) // Update React state
}

// ❌ Wrong: No cleanup
useEffect(() => {
  gsap.to(meshRef.current.rotation, { y: Math.PI * 2, repeat: -1 })
}, [])

// ✅ Correct: Cleanup on unmount
useEffect(() => {
  const tween = gsap.to(meshRef.current.rotation, { y: Math.PI * 2, repeat: -1 })

  return () => {
    tween.kill()
  }
}, [])