浅析ThreeJs中如何实现动画效果

import * as THREE from 'three';

// 创建场景、相机和渲染器
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();
const material = new THREE.MeshBasicMaterial({ color: 0x00ff00 });
const cube = new THREE.Mesh(geometry, material);
scene.add(cube);

// 设置相机位置
camera.position.z = 5;

function animate() {
  requestAnimationFrame(animate);

  // 更新立方体的旋转
  cube.rotation.x += 0.01; // 绕 x 轴旋转
  cube.rotation.y += 0.01; // 绕 y 轴旋转

  renderer.render(scene, camera);
}

animate();

let direction = 1;

function animate() {
  requestAnimationFrame(animate);
  // 更新立方体的位置
  cube.position.y += 0.02 * direction; // 上下移动

  // 碰到边界反向移动
  if (cube.position.y > 2 || cube.position.y < -2) {
    direction *= -1; // 反向移动
  }
  renderer.render(scene, camera);
}

animate();

let clock = new THREE.Clock();

function animate() {
  requestAnimationFrame(animate);

  const elapsedTime = clock.getElapsedTime(); // 获取经过的时间
  cube.position.y = Math.sin(elapsedTime) * 2; // 使用正弦函数实现上下波动

  renderer.render(scene, camera);
}

animate();