Spline 3D Integration

Master guide for embedding interactive 3D scenes from Spline.design into web projects.

What Is Spline?

Spline is a browser-based 3D design tool — think of it as Figma, but for 3D. Designers create interactive 3D scenes (objects, materials, animations, physics, events) in the Spline editor, then export them for the web.

• Free tier available (with watermark)
• Scenes are hosted by Spline and loaded at runtime
• Supports mouse, scroll, keyboard, and touch interactions
• Built on WebGL — works in all modern browsers

Prerequisites

Before using any React examples, install the required packages:

npm install @splinetool/react-spline @splinetool/runtime

Always install both together — version mismatches cause blank screens or TypeErrors.

Integration Methods

There are 3 ways to embed a Spline scene. Choose based on your stack:

Decision Guide

Is this a React or Next.js project?
  → YES: Use @splinetool/react-spline (see REACT_INTEGRATION.md)
  → NO:
      Do you need programmatic control (events, variables, animations)?
        → YES: Use @splinetool/runtime (see VANILLA_INTEGRATION.md)
        → NO: Use iframe embed (simplest option)

Quick Start

Getting the Scene URL

1. Open your scene in the Spline editor
2. Click Export (top-right)
3. Select Code
4. Choose React or Vanilla JS
5. Copy the scene URL — it looks like:

   https://prod.spline.design/aBcDeFgHiJkLmNoP/scene.splinecode

Important: The URL contains a unique scene ID. Each time you re-export, Spline generates a new URL. Use the latest one.

React (10 lines)

npm install @splinetool/react-spline @splinetool/runtime

import Spline from '@splinetool/react-spline';

export default function MyScene() {
  return (
    <div style={{ width: '100%', height: '100vh' }}>
      <Spline scene="https://prod.spline.design/YOUR_SCENE_ID/scene.splinecode" />
    </div>
  );
}

Vanilla JS (10 lines)

<canvas id="canvas3d" style="width: 100%; height: 100vh;"></canvas>
<script type="module">
  import { Application } from 'https://esm.sh/@splinetool/runtime';

  const canvas = document.getElementById('canvas3d');
  const spline = new Application(canvas);
  spline.load('https://prod.spline.design/YOUR_SCENE_ID/scene.splinecode')
    .then(() => console.log('Scene loaded!'));
</script>

iframe (1 line)

<iframe src="https://my.spline.design/YOUR_SCENE_ID/" width="100%" height="600" frameborder="0"></iframe>

Runtime API — Key Methods

Once a scene is loaded, you can interact with it programmatically. These methods work in both React (via onLoad callback) and vanilla JS (via the Application instance).

Getting a Reference

React:

function handleLoad(splineApp) {
  // splineApp is your runtime reference
  const cube = splineApp.findObjectByName('Cube');
}

<Spline scene="..." onLoad={handleLoad} />

Vanilla JS:

spline.load('...').then(() => {
  const cube = spline.findObjectByName('Cube');
});

Object Queries

Triggering Events

You can trigger events that are already defined in the Spline editor:

// Trigger a mouseDown event on an object by name
splineApp.emitEvent('mouseDown', 'Cube');

// Trigger by object ID
splineApp.emitEventReverse('mouseDown', 'object-uuid');

Supported event types: mouseDown, mouseUp, mouseHover, keyDown, keyUp, start, lookAt, follow

Listening to Events

splineApp.addEventListener('mouseDown', (e) => {
  console.log('Clicked:', e.target.name);
  console.log('Position:', e.target.position);
});

splineApp.addEventListener('mouseHover', (e) => {
  document.body.style.cursor = 'pointer';
});

Variables

Spline scenes can have variables (defined in the editor). You can read and write them from code:

// Read
const score = splineApp.getVariable('score');

// Write — this updates the scene in real-time
splineApp.setVariable('score', 42);
splineApp.setVariable('isActive', true);
splineApp.setVariable('userName', 'Visitor');

Use case: Drive 3D animations from your app data. For example, set a progress variable that controls a loading bar animation inside the Spline scene.

Object Properties (Direct Manipulation)

Once you have an object reference, you can modify it directly:

const cube = splineApp.findObjectByName('Cube');

// Position
cube.position.x = 2;
cube.position.y = 0;
cube.position.z = -1;

// Rotation (radians)
cube.rotation.y = Math.PI / 4;

// Scale
cube.scale.x = 1.5;
cube.scale.y = 1.5;
cube.scale.z = 1.5;

Common Patterns

1. Hero Section with 3D Scene

The most popular pattern — a split layout with text on one side and a 3D scene on the other. See examples/react-spline-wrapper.tsx for the recommended lazy-loaded component.

<div className="hero">
  <div className="hero-text">
    <h1>Welcome</h1>
    <p>Some subtitle text</p>
  </div>
  <div className="hero-3d">
    <SplineScene scene="https://prod.spline.design/.../scene.splinecode" />
  </div>
</div>

Key tips:

• Always lazy-load the Spline component (it's a heavy library)
• Show a loading spinner/skeleton while the scene loads
• Use flex or grid for the split layout
• On mobile, stack vertically or consider hiding the 3D scene entirely

2. Interactive Product Viewer

Let users rotate, zoom, and interact with a 3D product:

function ProductViewer({ sceneUrl }) {
  const handleLoad = (app) => {
    // Listen for clicks on hotspots
    app.addEventListener('mouseDown', (e) => {
      if (e.target.name === 'Hotspot_1') {
        showProductDetail('screen');
      }
    });
  };

  return <Spline scene={sceneUrl} onLoad={handleLoad} />;
}

3. Scroll-Driven 3D

Connect scroll position to a Spline variable to create scroll-triggered 3D animations:

const splineApp = /* your loaded app */;

window.addEventListener('scroll', () => {
  const scrollPercent = window.scrollY / (document.body.scrollHeight - window.innerHeight);
  splineApp.setVariable('scrollProgress', scrollPercent);
});

Then in the Spline editor, use the scrollProgress variable to drive animations (0 to 1).

4. Data-Driven 3D Dashboard

Update 3D visualizations from live data:

async function updateDashboard() {
  const data = await fetch('/api/metrics').then(r => r.json());

  splineApp.setVariable('revenue', data.revenue);
  splineApp.setVariable('users', data.activeUsers);
  splineApp.setVariable('status', data.systemStatus);
}

// Update every 5 seconds
setInterval(updateDashboard, 5000);

Performance Best Practices

This is the #1 issue people hit with Spline. Follow these rules:

The Big 8

Lazy Loading Pattern (React)

Always lazy-load the Spline component. The @splinetool/runtime package is ~500KB+.

import { Suspense, lazy } from 'react';

const Spline = lazy(() => import('@splinetool/react-spline'));

export function SplineScene({ scene, className }) {
  return (
    <Suspense
      fallback={
        <div className="spline-loader">
          <div className="spinner" />
        </div>
      }
    >
      <Spline scene={scene} className={className} />
    </Suspense>
  );
}

Spline Editor Optimization Checklist

Before exporting, run through this in the Spline editor:

1. Open the Performance panel (View → Performance)
2. Check polygon count — aim for under 150k
3. Remove any hidden or off-screen objects
4. Reduce segments on smooth objects (spheres, cylinders)
5. Under Export settings:
   • Set Geometry Quality to "Performance"
   • Enable Image Compression
6. Test on mobile — if it's slow, simplify further

Gotchas & Troubleshooting

CORS Issues

Problem: Scene won't load, browser console shows CORS errors. Solution: Download the .splinecode file from Spline's export panel and self-host it. Serve it from your own domain or a CDN.

// Instead of Spline's URL
<Spline scene="https://prod.spline.design/abc123/scene.splinecode" />

// Self-hosted
<Spline scene="/assets/scene.splinecode" />

Version Mismatches

Problem: TypeError or blank screen after install. Solution: Make sure @splinetool/react-spline and @splinetool/runtime versions are compatible. Install them together:

npm install @splinetool/react-spline@latest @splinetool/runtime@latest

Scene Loads but Shows Blank White

Problem: Container has 0 height. Solution: The Spline component fills its parent. Make sure the parent has explicit dimensions:

.spline-container {
  width: 100%;
  height: 100vh; /* or any fixed/relative height */
  position: relative;
}

Mobile Performance

Problem: Scene is laggy or crashes on phones. Solutions:

• Reduce polygon count significantly (under 50k for mobile)
• Use fewer lights (1-2 max)
• Consider showing a static image on mobile instead:

function ResponsiveScene({ scene, fallbackImage }) {
  const isMobile = window.innerWidth < 768;

  if (isMobile) {
    return <img src={fallbackImage} alt="3D scene" />;
  }

  return <SplineScene scene={scene} />;
}

Loading UX

Problem: Users see a blank space for 2-5 seconds while the scene loads. Solution: Always show a loader. Use the onLoad callback to hide it:

function SceneWithLoader({ scene }) {
  const [loaded, setLoaded] = useState(false);

  return (
    <div className="scene-container">
      {!loaded && <div className="spinner" />}
      <Spline
        scene={scene}
        onLoad={() => setLoaded(true)}
        style={{ opacity: loaded ? 1 : 0, transition: 'opacity 0.5s' }}
      />
    </div>
  );
}

Detailed Guides

• React & Next.js Integration — Lazy loading, wrapper components, Next.js specifics, TypeScript
• Vanilla JS Integration — Canvas setup, CDN usage, event handling, animation loops
• Performance Optimization — Deep dive on scene optimization, export settings, mobile strategies

Examples

• react-spline-wrapper.tsx — Production-ready lazy-loaded React wrapper
• vanilla-embed.html — Minimal vanilla JS embed
• interactive-scene.tsx — Full interactive example with events, variables, and camera