计时器、模型对象平移函数、枚举定义的使用
对应unity中的一些常用功能

import * as THREE from 'three';const scene = new THREE.Scene();
const camera = new THREE.PerspectiveCamera(60, 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(1, 1, 1);
const material = new THREE.MeshBasicMaterial({ color: 0x00ff00 });
const cube = new THREE.Mesh(geometry, material);
scene.add(cube);
camera.position.z = 50;//枚举定义
const direction = {UP: '上',DOWN: '下',LEFT: '左',RIGHT: '右'
};let state;
function changeState(dir) {console.log("dir=" + dir);if (state != dir) {state = dir;}
}//计时器
const clock = new THREE.Clock();
let timer = 0;
//枚举索引，不会js的int转枚举语法
let stateIndex = 1;
function updateChangeState() {timer += clock.getDelta();if (timer >= 3) {timer = 0;stateIndex++;if (stateIndex == 5) {stateIndex = 1;}changeState(convertToEnum(stateIndex));}
}//自定义int转枚举方法
function convertToEnum(value) {switch (value) {case 1:return direction.UP;case 2:return direction.LEFT;case 3:return direction.DOWN;case 4:return direction.RIGHT;}
}//更新模型位置
function updateSetObjPosition() {switch (state) {case direction.UP:cube.translateY(0.1);break;case direction.DOWN:cube.translateY(-0.1);break;case direction.LEFT:cube.translateX(-0.1);break;case direction.RIGHT:cube.translateX(0.1);break;}
}function animate() {requestAnimationFrame(animate);updateChangeState();updateSetObjPosition();renderer.render(scene, camera);
}animate();