几何体_顶点_索引_面之BufferGeometry

代码

import * as THREE from 'three'
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
import { GUI } from 'three/examples/jsm/libs/lil-gui.module.min.js';
const scene = new THREE.Scene();

const camera = new THREE.PerspectiveCamera(
  45,
  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.BufferGeometry()
// 使用顶点绘制：创建顶点数据, 顶点是有序的，每三个为一个顶点，逆时针为正面
// const vertices = new Float32Array([
//   // 三角形
//   // -1.0, -1.0, 0.0,
//   // 1.0, -1.0, 0.0,
//   // 1.0, 1.0, 0.0,

//   // 三角形
//   // -1.0, -1.0, 0.0,
//   // 1.0, 1.0, 0.0,
//   // 1.0, -1.0, 0.0,

//   // 正方形：两个三角形组成
//   -1.0, -1.0, 0.0,1.0, -1.0, 0.0, 1.0, 1.0, 0.0,
//   1.0, 1.0, 0.0, -1.0, 1.0, 0.0, -1.0, -1.0, 0.0,
// ])

// // 创建顶点属性
// geometry.setAttribute(
//   'position',
//   // 3个数据为一个顶点
//   new THREE.BufferAttribute(vertices, 3),
// )

// 使用索引绘制
const vertices = new Float32Array([
  -1.0, -1.0, 0.0, 1.0, -1.0, 0.0, 1.0, 1.0, 0.0, -1.0, 1.0, 0
])
// 创建顶点属性
geometry.setAttribute(
  'position',
  new THREE.BufferAttribute(vertices, 3),
)
// 创建索引
const indices = new Uint16Array([0, 1, 2, 2, 3, 0])
// 设置索引属性
geometry.setIndex(new THREE.BufferAttribute(indices, 1))

// 创建材质
const material = new THREE.MeshBasicMaterial({
  color: 0x00ff00,
  // side: THREE.DoubleSide, // 双面显示
  wireframe: true, // 线框模式
})

const plane = new THREE.Mesh(geometry, material)

scene.add(plane)
camera.position.z = 5;
camera.position.y = 2;
camera.position.x = 2;
camera.lookAt(0, 0, 0)

const axesHelper = new THREE.AxesHelper(5);
scene.add(axesHelper);

const controls = new OrbitControls(camera, renderer.domElement);

controls.enableDamping = true;

controls.dampingFactor = 0.05;

function animate() {
  requestAnimationFrame(animate)
  controls.update()

  renderer.render(scene, camera)
}

animate()

window.addEventListener('resize', () => {

  renderer.setSize(window.innerWidth, innerHeight)

  camera.aspect = window.innerWidth / window.innerHeight

  camera.updateProjectionMatrix()
})

let eventObj = {
  Fullscreen: function () {
    document.body.requestFullscreen()
  },
  ExitFullscreen: function () {
    document.exitFullscreen()
  }
}


const gui = new GUI()

gui.add(eventObj, 'Fullscreen').name('全屏')
gui.add(eventObj, 'ExitFullscreen').name('退出全屏')