Building a SketchUp-like Editor with Three.js

To create a SketchUp-like editor for custom shapes in Three.js, you'll need to combine several components from the library. Based on the available documentation, here are the key elements you should consider:

Core Components

Geometries

Three.js offers various built-in geometries that can serve as building blocks:

• BoxGeometry, SphereGeometry, CylinderGeometry for basic shapes
• ExtrudeGeometry for creating 3D shapes from 2D paths (essential for SketchUp-like extrusions)
• ShapeGeometry for 2D shapes

Addon Geometries

Consider these additional geometries from the addons:

• ConvexGeometry for creating shapes from points
• TextGeometry for adding text elements
• ParametricGeometry for custom mathematical surfaces

User Interaction Controls

The following controls will be essential for your editor:

• TransformControls - Allows users to translate, rotate, and scale objects directly in the scene
• DragControls - Enables dragging objects in the scene
• OrbitControls - Provides camera navigation similar to SketchUp's orbit functionality

Utilities

These utilities will help with geometry manipulation:

• BufferGeometryUtils - For merging, modifying, and optimizing geometries
• SceneUtils - Helpful for scene management

Implementation Approach

1. Basic Scene Setup:

   • Implement OrbitControls for navigation
   • Set up a grid and axes helpers for reference

2. Shape Creation Tools:

   • Create a toolbar with primitive shapes
   • Implement TransformControls for manipulating objects

3. Advanced Editing:

   • Implement extrusion tools using ExtrudeGeometry
   • Add boolean operations (union, subtract, intersect) for combining shapes
   • Create edge modification tools

4. User Interface:

   • Develop a properties panel for adjusting object parameters
   • Create layer management similar to SketchUp

Example Implementation Structure

JAVASCRIPTCopied
import * as THREE from 'three';
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js';
import { TransformControls } from 'three/examples/jsm/controls/TransformControls.js';
import { DragControls } from 'three/examples/jsm/controls/DragControls.js';

// Scene setup
const scene = new THREE.Scene();
const camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
const renderer = new THREE.WebGLRenderer({ antialias: true });
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);

// Controls
const orbitControls = new OrbitControls(camera, renderer.domElement);
const transformControls = new TransformControls(camera, renderer.domElement);
scene.add(transformControls);

// Grid helper
const gridHelper = new THREE.GridHelper(20, 20);
scene.add(gridHelper);

// Selected object tracking
let selectedObject = null;

// Function to create a new shape
function createShape(type, params) {
  let geometry;
  
  switch(type) {
    case 'box':
      geometry = new THREE.BoxGeometry(params.width, params.height, params.depth);
      break;
    case 'cylinder':
      geometry = new THREE.CylinderGeometry(params.radius, params.radius, params.height);
      break;
    // Add more shape types as needed
  }
  
  const material = new THREE.MeshStandardMaterial({ color: params.color || 0x00ff00 });
  const mesh = new THREE.Mesh(geometry, material);
  scene.add(mesh);
  
  return mesh;
}

// Example of attaching transform controls to an object
function selectObject(object) {
  selectedObject = object;
  transformControls.attach(object);
}

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

This is a starting point, and you would need to expand it significantly to achieve a full SketchUp-like experience. Consider looking at existing Three.js editors like Three.js Editor itself for inspiration on UI and functionality implementation.