Web3d Integration Patterns

# Web 3D Integration Patterns

## Overview

This meta-skill provides architectural patterns, best practices, and integration strategies for combining multiple 3D and animation libraries in web applications. It synthesizes knowledge from the threejs-webgl, gsap-scrolltrigger, react-three-fiber, motion-framer, and react-spring-physics skills into cohesive patterns for building complex, performant 3D web experiences.

**When to use this skill:**
- Building complex 3D applications that combine multiple libraries
- Creating scroll-driven 3D experiences with animation orchestration
- Implementing physics-based interactions with 3D scenes
- Managing state across 3D rendering and UI animations
- Optimizing performance in multi-library architectures
- Designing reusable component architectures for 3D applications
- Migrating between or combining animation approaches

**Core Integration Combinations:**
1. **Three.js + GSAP** - Scroll-driven 3D animations, timeline orchestration
2. **React Three Fiber + Motion** - State-based 3D with declarative animations
3. **React Three Fiber + GSAP** - Complex 3D sequences in React
4. **React Three Fiber + React Spring** - Physics-based 3D interactions
5. **Three.js + GSAP + React** - Hybrid imperative/declarative 3D

## Architecture Patterns

### Pattern 1: Layered Separation (Three.js + GSAP + React UI)

**Use case:** 3D scene with overlaid UI, scroll-driven animations

**Architecture:**
```
├── 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
```

**Implementation:**

```javascript
// 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>
  )
}
```

```javascript
// 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 = ne