three.js官方CSS2DRender案例学习

import * as THREE from 'three';
import { CSS2DRenderer, CSS2DObject } from 'three/examples/jsm/renderers/CSS2DRenderer.js';
 
let scene, camera, renderer, labelRenderer, mesh;
 
function init() {
    scene = new THREE.Scene();
 
    camera = new THREE.PerspectiveCamera(70, window.innerWidth / window.innerHeight, 0.01, 10);
    camera.position.z = 1;
 
    renderer = new THREE.WebGLRenderer({ antialias: true });
    renderer.setSize(window.innerWidth, window.innerHeight);
    document.body.appendChild(renderer.domElement);
 
    // 创建CSS2DRenderer
    labelRenderer = new CSS2DRenderer();
    labelRenderer.setSize(window.innerWidth, window.innerHeight);
    labelRenderer.domElement.style.position = 'absolute';
    labelRenderer.domElement.style.top = 0;
    document.body.appendChild(labelRenderer.domElement);
 
    // 创建3D对象
    let geometry = new THREE.PlaneGeometry(0.5, 0.5);
    let material = new THREE.MeshBasicMaterial({ color: 0x00ff00, transparent: true });
    mesh = new THREE.Mesh(geometry, material);
    scene.add(mesh);
 
    // 创建CSS2DObject
    let label = document.createElement('div');
    label.style.color = 'red';
    label.textContent = 'Hello, CSS2D!\n3D object!';
    let labelObject = new CSS2DObject(label);
    labelObject.position.set(0, 0, 0);
    scene.add(labelObject);
 
    // 监听窗口大小变化
    window.addEventListener('resize', onWindowResize, false);
 
    animate();
}
 
function onWindowResize() {
    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();
 
    renderer.setSize(window.innerWidth, window.innerHeight);
    labelRenderer.setSize(window.innerWidth, window.innerHeight);
}
 
function animate() {
    requestAnimationFrame(animate);
 
    renderer.render(scene, camera);
    labelRenderer.render(scene, camera);
}
 
init();

这段代码初始化了Three.js场景，并使用CSS2DRenderer渲染了一个2D标签，它会随着3D对象一起旋转。这个例子简单地展示了如何将HTML元素与3D场景中的对象相关联，这在创建交互式数据可视化时非常有用。