星系 ·Galaxy Star· ▶ 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-examples400个案例代码:网盘链接你将学到什么OrbitControls 相机轨道交互THREE.Points 粒子点渲染BufferGeometry 自定义顶点/索引数据requestAnimationFrame渲染循环与resize自适应效果说明本案例演示星系效果基于 WebGL 实现「星系」可视化效果附完整可运行源码核心用到 OrbitControls、THREE.Points、BufferGeometry。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()。THREE.Points将每个顶点渲染为可控大小的粒子可用自定义 attribute如u_index驱动片元/顶点动画。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 renderCesium 为viewer.render或自动渲染代码要点import * as THREE from three;import { GUI } from three/addons/libs/lil-gui.module.min.js; import Stats from three/examples/jsm/libs/stats.module.js; import { OrbitControls } from three/examples/jsm/controls/OrbitControls.js;const initializeScene ({ root, antialias true } {}) { // Create scene const scene new THREE.Scene();// Create camera const camera new THREE.PerspectiveCamera( 35, window.innerWidth / window.innerHeight, 0.1, 1000, ); camera.position.z 110;// Create renderer const renderer new THREE.WebGLRenderer({ antialias }); renderer.setSize(window.innerWidth, window.innerHeight); // renderer.setPixelRatio(Math.min(window.devicePixelRatio, 2)); const controls new OrbitControls(camera, renderer.domElement); controls.enableDamping true; root.appendChild(renderer.domElement);const onWindowResize () { // Adjust camera and renderer on window resize camera.aspect window.innerWidth / window.innerHeight; camera.updateProjectionMatrix(); controls.update(); renderer.setSize(window.innerWidth, window.innerHeight); renderer.render(scene, camera); }; onWindowResize(); window.addEventListener(resize, onWindowResize, false);// Create GUI const gui new GUI({ container: root });const stats new Stats(); stats.showPanel(0); root.appendChild(stats.domElement);return { scene, renderer, camera, controls, gui, stats, }; } const getRandomPolarCoordinate (radius) { const theta Math.random()Math.PI2; const phi Math.random()Math.PI2; const x radiusMath.sin(theta)Math.cos(phi); const y radiusMath.sin(theta)Math.sin(phi); const z radius * Math.cos(theta); return { x, y, z }; }const init (root) { const params { particleCount: 250000, particleSize: 0.02, branches: 6, branchRadius: 5, spin: 0.2, radialRandomness: 0.5, innerColor: #ff812e, outerColor: #a668ff, };const { scene, renderer, camera, gui, stats, controls } initializeScene({ root, });camera.position.set(7, 4, 7); controls.update();let spinDirection 1; let material null; let geometry null; let points null;const particleTexture new THREE.TextureLoader().load(FILE_HOST threeExamples/shader/star.png);const generateGalaxy () { // Remove old particles if (points) { geometry.dispose(); material.dispose(); scene.remove(points); }// Create new particles const positions new Float32Array(params.particleCount * 3); const colors new Float32Array(params.particleCount * 3); const innerColor new THREE.Color(params.innerColor); const outerColor new THREE.Color(params.outerColor); for (let i 0; i params.particleCount; i) { const i3 i * 3;const radius params.branchRadius * Math.random(); const branchAngle ((i % params.branches) / params.branches)Math.PI2; const spinAngle params.spinradiusMath.PI * 2;const randRadius Math.random()params.radialRandomnessradius; const { x: randX, y: randY, z: randZ, } getRandomPolarCoordinate(randRadius);positions[i3] radius * Math.cos(branchAngle spinAngle) randX; positions[i3 1] randY; positions[i3 2] radius * Math.sin(branchAngle spinAngle) randZ;const mixedColor innerColor .clone() .lerp(outerColor, radius / params.branchRadius); colors[i3] mixedColor.r; colors[i3 1] mixedColor.g; colors[i3 2] mixedColor.b; }material new THREE.PointsMaterial({ size: params.particleSize, sizeAttenuation: true, depthWrite: false, blending: THREE.AdditiveBlending, vertexColors: true, transparent: true, alphaMap: particleTexture, }); geometry new THREE.BufferGeometry(); geometry.setAttribute(position, new THREE.BufferAttribute(positions, 3)); geometry.setAttribute(color, new THREE.BufferAttribute(colors, 3));points new THREE.Points(geometry, material); scene.add(points);spinDirection params.spin 0 ? 1 : -1; };generateGalaxy();// Create GUI gui.width 360; gui .add(params, particleCount, 5000, 500000, 100) .onFinishChange(generateGalaxy); gui.add(params, particleSize, 0.005, 0.15).onFinishChange(generateGalaxy); gui.add(params, branches, 2, 15, 1).onFinishChange(generateGalaxy); gui.add(params, branchRadius, 1, 10).onFinishChange(generateGalaxy); gui.add(params, spin, -1, 1).onFinishChange(generateGalaxy); gui.add(params, radialRandomness, 0, 1).onFinishChange(generateGalaxy); gui.addColor(params, innerColor).onFinishChange(generateGalaxy); gui.addColor(params, outerColor).onFinishChange(generateGalaxy);const tick () { requestAnimationFrame(tick); stats.begin();controls.update();geometry.rotateY(0.001 * spinDirection);stats.end(); renderer.render(scene, camera); };tick(); };init(document.getElementById(box));完整源码GitHub小结本文提供星系完整 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
