Replay AI for Building a Three.js 3D Interface

TL;DR: Replay AI allows developers to quickly prototype and generate Three.js 3D interfaces from video recordings of desired interactions, significantly accelerating development time.

From Video to 3D: Building Three.js Interfaces with Replay AI#

Building interactive 3D interfaces with Three.js can be a complex and time-consuming process. Defining the scene, handling user interactions, and managing state all require significant effort. What if you could simply show the desired behavior and have the code generated for you? Replay AI makes this a reality.

Traditional code generation tools often rely on static screenshots, which lack the dynamic context of user interactions. Replay AI, on the other hand, analyzes video recordings to understand the intent behind the user's actions, enabling it to generate more accurate and functional code. This is especially powerful for complex 3D interfaces where subtle movements and interactions are crucial.

The Problem: Traditional 3D Development Bottlenecks#

Developing 3D interfaces with Three.js typically involves:

• •Scene Setup: Manually defining the 3D environment, including objects, lighting, and camera.
• •Interaction Handling: Writing code to respond to user input, such as mouse clicks, keyboard presses, and touch gestures.
• •State Management: Tracking the state of the 3D scene and updating it in response to user actions.
• •Performance Optimization: Ensuring smooth and responsive performance, especially on lower-powered devices.

These steps can be tedious and error-prone, especially for complex interfaces. Replay AI addresses these bottlenecks by automating the code generation process.

Replay: Behavior-Driven Reconstruction for 3D#

Replay uses "Behavior-Driven Reconstruction" to analyze video recordings and generate working Three.js code. Here's how it works:

1. •Video Input: You provide a video recording of the desired 3D interface behavior. This could be a demonstration of a user interacting with a prototype, or a recording of an existing application.
2. •Behavior Analysis: Replay analyzes the video to understand the user's actions and the corresponding changes in the 3D scene. This includes identifying objects, tracking their movements, and recognizing user gestures.
3. •Code Generation: Replay generates Three.js code that replicates the observed behavior. This includes code for scene setup, interaction handling, and state management.

Key Features for 3D Interface Generation#

Replay offers several key features that are particularly useful for building 3D interfaces:

• •Multi-page generation: For complex workflows that span multiple views or states, Replay can generate code that seamlessly transitions between them. Imagine demonstrating a multi-step animation sequence – Replay can capture and recreate the entire flow.
• •Style injection: Replay can infer styling information from the video and apply it to the generated code, ensuring a visually consistent result. This includes colors, fonts, and other visual properties.
• •Product Flow Maps: Replay automatically generates diagrams visualizing the user flow captured in the video, providing a valuable overview of the application's structure. This is extremely useful for understanding complex interactions and debugging issues.

Comparing Replay to Traditional Methods#

Building a Simple 3D Scene with Replay: A Step-by-Step Guide#

Let's walk through a simplified example of using Replay to generate a Three.js scene. Imagine you want to create a scene with a rotating cube that changes color when clicked.

Step 1: Record the Interaction#

Record a video of yourself interacting with a simple prototype. The prototype can be a basic HTML page with a placeholder for the 3D scene. Show yourself clicking on the cube, and its color changing. Focus on clearly demonstrating the desired behavior.

Step 2: Upload to Replay#

Upload the video to Replay. Replay will analyze the video and identify the key elements and interactions.

Step 3: Review and Refine#

Review the generated code. Replay provides a visual interface for inspecting the generated code and making adjustments. You can fine-tune the code to match your specific requirements.

Step 4: Integrate into Your Project#

Integrate the generated code into your Three.js project. The code will include the scene setup, interaction handling, and state management logic.

Here's an example of the kind of code Replay might generate for this scenario:

typescript
// Generated by Replay AI
import * as THREE from 'three';

const scene = new THREE.Scene();
const camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight, 0.1, 1000 );

const renderer = new THREE.WebGLRenderer();
renderer.setSize( window.innerWidth, window.innerHeight );
document.body.appendChild( renderer.domElement );

const geometry = new THREE.BoxGeometry();
let material = new THREE.MeshBasicMaterial( { color: 0x00ff00 } );
const cube = new THREE.Mesh( geometry, material );
scene.add( cube );

camera.position.z = 5;

let isRotating = true;

const animate = () => {
  requestAnimationFrame( animate );

  if (isRotating) {
    cube.rotation.x += 0.01;
    cube.rotation.y += 0.01;
  }

  renderer.render( scene, camera );
};

animate();

const onClick = () => {
  material.color.setHex(Math.random() * 0xffffff);
  isRotating = !isRotating;
};

window.addEventListener('click', onClick);

💡 Pro Tip: For best results, ensure your video is clear, well-lit, and demonstrates the desired behavior as explicitly as possible. The clearer the input, the more accurate the output.

Advanced Use Cases#

Replay's capabilities extend far beyond simple rotating cubes. Consider these advanced use cases:

• •Interactive Product Configurators: Generate code for complex product configurators where users can customize various aspects of a 3D model.
• •Virtual Reality (VR) Interfaces: Create VR interfaces by recording interactions with a VR headset and using Replay to generate the corresponding code.
• •Game Development Prototypes: Quickly prototype game mechanics by recording gameplay footage and using Replay to generate the core game logic.

📝 Note: Replay is constantly evolving, with new features and capabilities being added regularly. Check the documentation for the latest updates.

Integrating with Supabase#

Replay seamlessly integrates with Supabase, allowing you to easily store and manage the state of your 3D interfaces. You can use Supabase to store user preferences, game scores, and other data.

For example, Replay can generate code that automatically saves the cube's color to Supabase when it's changed:

typescript
// Example Supabase integration (requires Supabase setup)
import { createClient } from '@supabase/supabase-js';

const supabaseUrl = 'YOUR_SUPABASE_URL';
const supabaseKey = 'YOUR_SUPABASE_ANON_KEY';
const supabase = createClient(supabaseUrl, supabaseKey);

const onClick = async () => {
  const newColor = Math.random() * 0xffffff;
  material.color.setHex(newColor);
  isRotating = !isRotating;

  // Save the color to Supabase
  const { data, error } = await supabase
    .from('cube_state')
    .upsert([{ color: newColor }]);

  if (error) {
    console.error('Error saving color to Supabase:', error);
  } else {
    console.log('Color saved to Supabase:', data);
  }
};

window.addEventListener('click', onClick);

⚠️ Warning: Remember to replace

text

YOUR_SUPABASE_URL

and

text

YOUR_SUPABASE_ANON_KEY

with your actual Supabase credentials. Never commit your Supabase key directly to your repository. Use environment variables instead.

The Future of 3D Development#

Replay represents a significant step forward in the evolution of 3D development. By leveraging the power of AI to understand user behavior, Replay enables developers to build complex and interactive 3D interfaces with unprecedented speed and ease.

• •Faster prototyping
• •Reduced development costs
• •Increased innovation

Frequently Asked Questions#

Is Replay free to use?#

Replay offers a free tier with limited usage. Paid plans are available for increased usage and access to advanced features. Check the Replay pricing page for the latest details.

How is Replay different from v0.dev?#

While both Replay and v0.dev aim to accelerate UI development, they differ significantly in their approach. V0.dev relies primarily on text-based prompts and code generation, whereas Replay analyzes video recordings to understand user behavior and generate code based on observed interactions. Replay excels at capturing dynamic interactions and complex workflows, which are difficult to describe with text alone. Replay focuses on behavior, not just appearance.

What frameworks does Replay support?#

Currently, Replay has been optimized for React and Three.js, but the team is rapidly expanding support for other frameworks and libraries.

Ready to try behavior-driven code generation? Get started with Replay - transform any video into working code in seconds.