视频碎片 ·Video Effect· ▶ 在线运行案例
- 案例合集:三维可视化功能案例(threehub.cn)
- 开源仓库github地址:https://github.com/z2586300277/three-cesium-examples
- 400个案例代码:网盘链接
你将学到什么
- OrbitControls 相机轨道交互
requestAnimationFrame渲染循环与resize自适应
效果说明
本案例演示视频碎片效果:基于 WebGL 实现「视频碎片」可视化效果,附完整可运行源码;核心用到 OrbitControls。建议先打开文首在线案例查看动态画面,再对照下方源码逐步理解。
核心概念
- Scene / Camera / WebGLRenderer构成最小渲染闭环;大场景可开
logarithmicDepthBuffer缓解 Z-fighting。 - OrbitControls提供轨道旋转/缩放;开启
enableDamping后需在 animate 中controls.update()。 - 阅读下方完整源码时,建议从
init/load/animate三条主线入手,再深入 shader 与工具函数。
实现步骤
- 搭建 Scene、PerspectiveCamera、WebGLRenderer,挂载 canvas 并处理
resize - 创建 OrbitControls(及 Raycaster 等交互控件,若源码包含)
- 在
requestAnimationFrame循环中更新状态并 render(Cesium 为viewer.render或自动渲染) 代码要点
import * as THREE from 'three'import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
const box = document.getElementById('box')
const scene = new THREE.Scene()
const camera = new THREE.PerspectiveCamera(50, box.clientWidth / box.clientHeight, 0.1, 1000)
camera.position.set(0, 0, 20)
const renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true, logarithmicDepthBuffer: true })
renderer.setSize(box.clientWidth, box.clientHeight)
box.appendChild(renderer.domElement)
const controls = new OrbitControls(camera, renderer.domElement)
controls.enableDamping = true
const video = document.createElement('video')
video.crossOrigin = 'anonymous' // 跨域
video.src = 'https://z2586300277.github.io/3d-file-server/video/test.mp4'
video.loop = true // 循环播放
video.muted = true // 静音
video.play()
const texture = await new Promise(r => video.onloadeddata = () => r(new THREE.VideoTexture(video))) // 创建视频纹理
const group = new THREE.Group() const config = { width: 16, height: 9, xGrid: 4, yGrid: 3, offset: 0.1 } const ux = 1 / config.xGrid const uy = 1 / config.yGrid const planeWidth = config.width / config.xGrid - config.offset const planeHeight = config.height / config.yGrid - config.offset for (let i = 0; i < config.xGrid; i++) { for (let j = 0; j < config.yGrid; j++) { // 创建 4 * 3 子平面实现整体效果 const geometry = new THREE.PlaneGeometry(planeWidth, planeHeight) const material = new THREE.MeshBasicMaterial({ map: texture, side: THREE.DoubleSide })
// 切割uv来实现纹理映射到全部平面 const uvs = geometry.attributes.uv.array for (let index = 0; index < uvs.length; index += 2) { uvs[index] = (uvs[index] + i) * ux uvs[index + 1] = (uvs[index + 1] + j) * uy }
const mesh = new THREE.Mesh(geometry, material)
mesh.dx = 0.004 * (0.5 - Math.random()) mesh.dy = 0.004 * (0.5 - Math.random())
const x = (i - config.xGrid / 2)planeWidth + planeWidth0.5 + (i * config.offset) / 2 const y = (j - config.yGrid / 2)planeHeight + planeHeight0.5 + (j * config.offset) / 2 mesh.position.set(x, y, 0) group.add(mesh)
}
} scene.add(group)
const clock = new THREE.Clock() animate()
function animate() {
const elapsedTime = clock.getElapsedTime()
for (const mesh of group.children) { mesh.rotation.x += Math.sin(elapsedTime0.1)mesh.dx; mesh.rotation.y += Math.sin(elapsedTime0.2)mesh.dy;
mesh.position.x -= Math.sin(elapsedTime0.1)mesh.dx; mesh.position.y += Math.sin(elapsedTime0.3)mesh.dy; mesh.position.z += Math.cos(elapsedTime0.2)mesh.dx; }
requestAnimationFrame(animate)
controls.update()
renderer.render(scene, camera)
}
window.onresize = () => {
renderer.setSize(box.clientWidth, box.clientHeight)
camera.aspect = box.clientWidth / box.clientHeight
camera.updateProjectionMatrix()
}完整源码:GitHub
小结
- 本文提供视频碎片完整 Three.js 源码与在线 Demo,建议先运行案例再改 uniform/参数做二次实验
- 更多 Three.js 实战案例见 three-cesium-examples 合集 与 GitHub 开源仓库