[webGL学习]基于three.js构建WebGL实例第一讲
2016-10-06 23:22
501 查看
我们主要做些的基本功能:创建一个场景,相机,渲染器,控制器(OrbitControls)。我们也将创建简单的定向光,加上一些对象(不同的几何形状)的阴影。为了使事情更快,我们决定采取一个最流行的WebGL框架——three.js。为什么使用three.js? 事实上,它是开源的JavaScript框架,它也是增长最迅速的和讨论很热烈的引擎 。在这里,已经准备了很多会用到的东西,从基本的点和向量,到做准备工作的场景、着色器,甚至立体效果。
HTML结构
<!DOCTYPE html> <html lang="en" > <head> <meta charset="utf-8" /> <meta name="author" content="Script Tutorials" /> <title>WebGL With Three.js - Lesson 1 | Script Tutorials</title> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"> <link href="css/main.css" rel="stylesheet" type="text/css" /> </head> <body> <script src="js/three.min.js"></script> <script src="js/THREEx.WindowResize.js"></script> <script src="js/OrbitControls.js"></script> <script src="js/stats.min.js"></script> <script src="js/script.js"></script> <div style="position: absolute; top: 10px; left: 20px; text-align: center;"> </div> <!-- Only used for Script Tutorial's Demo site. Please ignore and remove. --> <script src="http://code.jquery.com/jquery-1.11.0.min.js"></script> <script src="http://www.script-tutorials.com/assets/ads.js" async></script> </body> </html>
场景渲染
var lesson1 = { scene: null, camera: null, renderer: null, container: null, controls: null, clock: null, stats: null, init: function() { // Initialization // create main scene this.scene = new THREE.Scene(); var SCREEN_WIDTH = window.innerWidth, SCREEN_HEIGHT = window.innerHeight; // prepare camera var VIEW_ANGLE = 45, ASPECT = SCREEN_WIDTH / SCREEN_HEIGHT, NEAR = 1, FAR = 10000; this.camera = new THREE.PerspectiveCamera( VIEW_ANGLE, ASPECT, NEAR, FAR); this.scene.add(this.camera); this.camera.position.set(-1000, 1000, 0); this.camera.lookAt(new THREE.Vector3(0,0,0)); // prepare renderer this.renderer = new THREE.WebGLRenderer({antialias:true, alpha: false}); this.renderer.setSize(SCREEN_WIDTH, SCREEN_HEIGHT); this.renderer.setClearColor(0xffffff); this.renderer.shadowMapEnabled = true; this.renderer.shadowMapSoft = true; // prepare container this.container = document.createElement('div'); document.body.appendChild(this.container); this.container.appendChild(this.renderer.domElement); // events THREEx.WindowResize(this.renderer, this.camera); // prepare controls (OrbitControls) this.controls = new THREE.OrbitControls(this.camera, this.renderer.domElement); this.controls.target = new THREE.Vector3(0, 0, 0); // prepare clock this.clock = new THREE.Clock(); // prepare stats this.stats = new Stats(); this.stats.domElement.style.position = 'absolute'; this.stats.domElement.style.bottom = '0px'; this.stats.domElement.style.zIndex = 10; this.container.appendChild( this.stats.domElement ); // add directional light var dLight = new THREE.DirectionalLight(0xffffff); dLight.position.set(1, 1000, 1); dLight.castShadow = true; dLight.shadowCameraVisible = true; dLight.shadowDarkness = 0.2; dLight.shadowMapWidth = dLight.shadowMapHeight = 1000; this.scene.add(dLight); // add particle of light particleLight = new THREE.Mesh( new THREE.SphereGeometry(10, 10, 10), new THREE.MeshBasicMaterial({ color: 0x44ff44 })); particleLight.position = dLight.position; this.scene.add(particleLight); // add simple ground var groundGeometry = new THREE.PlaneGeometry(1000, 1000, 1, 1); ground = new THREE.Mesh(groundGeometry, new THREE.MeshLambertMaterial({ color: this.getRandColor() })); ground.position.y = 0; ground.rotation.x = - Math.PI / 2; ground.receiveShadow = true; this.scene.add(ground); // add circle shape var circle = new THREE.Mesh(new THREE.CircleGeometry(70, 50), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); circle.rotation.x = - Math.PI / 2; circle.rotation.y = - Math.PI / 3; circle.rotation.z = Math.PI / 3; circle.position.x = -300; circle.position.y = 150; circle.position.z = -300; circle.castShadow = circle.receiveShadow = true; this.scene.add(circle); // add cube shape var cube = new THREE.Mesh(new THREE.CubeGeometry(100, 100, 100), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); cube.rotation.x = cube.rotation.z = Math.PI * 0.1; cube.position.x = -300; cube.position.y = 150; cube.position.z = -100; cube.castShadow = cube.receiveShadow = true; this.scene.add(cube); // add cylinder shape var cube = new THREE.Mesh(new THREE.CylinderGeometry(60, 80, 90, 32), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); cube.rotation.x = cube.rotation.z = Math.PI * 0.1; cube.position.x = -300; cube.position.y = 150; cube.position.z = 100; cube.castShadow = cube.receiveShadow = true; this.scene.add(cube); // add extrude geometry shape var extrudeSettings = { amount: 10, steps: 10, bevelSegments: 10, bevelSize: 10, bevelThickness: 10 }; var triangleShape = new THREE.Shape(); triangleShape.moveTo( 0, -50 ); triangleShape.lineTo( -50, 50 ); triangleShape.lineTo( 50, 50 ); triangleShape.lineTo( 0, -50 ); var extrude = new THREE.Mesh(new THREE.ExtrudeGeometry(triangleShape, extrudeSettings), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); extrude.rotation.y = Math.PI / 2; extrude.position.x = -300; extrude.position.y = 150; extrude.position.z = 300; extrude.castShadow = extrude.receiveShadow = true; this.scene.add(extrude); // add icosahedron shape var icosahedron = new THREE.Mesh(new THREE.IcosahedronGeometry(70), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); icosahedron.position.x = -100; icosahedron.position.y = 150; icosahedron.position.z = -300; icosahedron.castShadow = icosahedron.receiveShadow = true; this.scene.add(icosahedron); // add octahedron shape var octahedron = new THREE.Mesh(new THREE.OctahedronGeometry(70), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); octahedron.position.x = -100; octahedron.position.y = 150; octahedron.position.z = -100; octahedron.castShadow = octahedron.receiveShadow = true; this.scene.add(octahedron); // add ring shape var ring = new THREE.Mesh(new THREE.RingGeometry(30, 70, 32), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); ring.rotation.y = -Math.PI / 2; ring.position.x = -100; ring.position.y = 150; ring.position.z = 100; ring.castShadow = ring.receiveShadow = true; this.scene.add(ring); // add shape geometry shape var shapeG = new THREE.Mesh(new THREE.ShapeGeometry(triangleShape), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); shapeG.rotation.y = -Math.PI / 2; shapeG.position.x = -100; shapeG.position.y = 150; shapeG.position.z = 300; shapeG.castShadow = shapeG.receiveShadow = true; this.scene.add(shapeG); // add sphere shape var sphere = new THREE.Mesh(new THREE.SphereGeometry(70, 32, 32), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); sphere.rotation.y = -Math.PI / 2; sphere.position.x = 100; sphere.position.y = 150; sphere.position.z = -300; sphere.castShadow = sphere.receiveShadow = true; this.scene.add(sphere); // add tetrahedron shape var tetrahedron = new THREE.Mesh(new THREE.TetrahedronGeometry(70), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); tetrahedron.position.x = 100; tetrahedron.position.y = 150; tetrahedron.position.z = -100; tetrahedron.castShadow = tetrahedron.receiveShadow = true; this.scene.add(tetrahedron); // add torus shape var torus = new THREE.Mesh(new THREE.TorusGeometry(70, 20, 16, 100), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); torus.rotation.y = -Math.PI / 2; torus.position.x = 100; torus.position.y = 150; torus.position.z = 100; torus.castShadow = torus.receiveShadow = true; this.scene.add(torus); // add torus knot shape var torusK = new THREE.Mesh(new THREE.TorusKnotGeometry(70, 20, 16, 100), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); torusK.rotation.y = -Math.PI / 2; torusK.position.x = 100; torusK.position.y = 150; torusK.position.z = 300; torusK.castShadow = torusK.receiveShadow = true; this.scene.add(torusK); // add tube shape var points = []; for (var i = 0; i < 10; i++) { var randomX = -100 + Math.round(Math.random() * 200); var randomY = -100 + Math.round(Math.random() * 200); var randomZ = -100 + Math.round(Math.random() * 200); points.push(new THREE.Vector3(randomX, randomY, randomZ)); } var tube = new THREE.Mesh(new THREE.TubeGeometry(new THREE.SplineCurve3(points), 64, 20), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); tube.rotation.y = -Math.PI / 2; tube.position.x = 0; tube.position.y = 500; tube.position.z = 0; tube.castShadow = tube.receiveShadow = true; this.scene.add(tube); }, getRandColor: function() { return colors[Math.floor(Math.random() * colors.length)]; } }; // Animate the scene function animate() { requestAnimationFrame(animate); render(); update(); } // Update controls and stats function update() { lesson1.controls.update(lesson1.clock.getDelta()); lesson1.stats.update(); // smoothly move the particleLight var timer = Date.now() * 0.000025; particleLight.position.x = Math.sin(timer * 5) * 300; particleLight.position.z = Math.cos(timer * 5) * 300; } // Render the scene function render() { if (lesson1.renderer) { lesson1.renderer.render(lesson1.scene, lesson1.camera); } } // Initialize lesson on page load function initializeLesson() { lesson1.init(); animate(); }
这是用 three.js 建应用的常用结构。几乎所有的东西都将在init方法里创建。
场景创建、相机和渲染
// 创建主要场景 this.scene = new THREE.Scene(); var SCREEN_WIDTH = window.innerWidth, SCREEN_HEIGHT = window.innerHeight; // 准备相机 var VIEW_ANGLE = 45, ASPECT = SCREEN_WIDTH / SCREEN_HEIGHT, NEAR = 1, FAR = 10000; this.camera = new THREE.PerspectiveCamera( VIEW_ANGLE, ASPECT, NEAR, FAR); this.scene.add(this.camera); this.camera.position.set(-1000, 1000, 0); this.camera.lookAt(new THREE.Vector3(0,0,0)); // 准备渲染 this.renderer = new THREE.WebGLRenderer({antialias:true, alpha: false}); this.renderer.setSize(SCREEN_WIDTH, SCREEN_HEIGHT); this.renderer.setClearColor(0xffffff); this.renderer.shadowMapEnabled = true; this.renderer.shadowMapSoft = true; // 准备容器 this.container = document.createElement('div'); document.body.appendChild(this.container); this.container.appendChild(this.renderer.domElement); // 事件 // events THREEx.WindowResize(this.renderer, this.camera);
我们将相机把相机放在45度角,设为全屏幕大小,WebGLRenderer设为白色,再把我们的场景添加到HTML文档中,而且在浏览器窗口大小变化时,用THREEx.WindowResize 来控制渲染和相机的变化。
OrbitControls 和 Stats
为了能够在某种程度上控制相机的 —— three.js 给我们提供了现成的控件。其中之一是 OrbitControls,它能在场景中绕其轴线旋转。一个小插件stats.min.js将有助于我们看到场景的统计(FPS)。// 准备控制器 this.controls = new THREE.OrbitControls(this.camera, this.renderer.domElement); this.controls.target = new THREE.Vector3(0, 0, 0); // 开始计数 this.clock = new THREE.Clock(); //开始统计 this.stats = new Stats(); this.stats.domElement.style.position = 'absolute'; this.stats.domElement.style.bottom = '0px'; this.stats.domElement.style.zIndex = 10; this.container.a
光和场地的创作
光是一个场景中的重要元素,在我们的第一个教程,我们将创建最简单的定向光线,因为我们要添加基本的阴影:// 添加定向光线 var dLight = new THREE.DirectionalLight(0xffffff); dLight.position.set(1, 1000, 1); dLight.castShadow = true; dLight.shadowCameraVisible = true; dLight.shadowDarkness = 0.2; dLight.shadowMapWidth = dLight.shadowMapHeight = 1000; this.scene.add(dLight); // 添加粒子光线 particleLight = new THREE.Mesh( new THREE.SphereGeometry(10, 10, 10), new THREE.MeshBasicMaterial({ color: 0x44ff44 })); particleLight.position = dLight.position; this.scene.add(particleLight); // 添加简单的场地 var groundGeometry = new THREE.PlaneGeometry(1000, 1000, 1, 1); ground = new THREE.Mesh(groundGeometry, new THREE.MeshLambertMaterial({ color: this.getRandColor() })); ground.position.y = 0; ground.rotation.x = - Math.PI / 2; ground.receiveShadow = true; this.scene.add(ground);
当我们创建灯光时,用了两个参数 castShadow 和 shadowCameraVisible。这将使我们能够直观地看到光在哪里,理解构造的过程(和边界)的阴影。
你也可能会注意到,在添加光后,我们增加了一个球形物体——为你准备的,以便直观地知道我们的定向光源在什么位置。我们用一个平面作为地面去接收阴影——我们设置的receiveShadow参数为true。
颜色设置
var colors = [ 0xFF62B0, 0x9A03FE, 0x62D0FF, 0x48FB0D, 0xDFA800, 0xC27E3A, 0x990099, 0x9669FE, 0x23819C, 0x01F33E, 0xB6BA18, 0xFF800D, 0xB96F6F, 0x4A9586 ]; getRandColor: function() { return colors[Math.floor(Math.random() * colors.length)]; }
我们将在场景中添加额外的对象。我用一个方法来生成不同颜色的部件。这个方法将从颜色列表中随机返回一个预定义的颜色。
建模型
// add simple ground var groundGeometry = new THREE.PlaneGeometry(1000, 1000, 1, 1); ground = new THREE.Mesh(groundGeometry, new THREE.MeshLambertMaterial({ color: this.getRandColor() })); ground.position.y = 0; ground.rotation.x = - Math.PI / 2; ground.receiveShadow = true; this.scene.add(ground); // add circle shape var circle = new THREE.Mesh(new THREE.CircleGeometry(70, 50), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); circle.rotation.x = - Math.PI / 2; circle.rotation.y = - Math.PI / 3; circle.rotation.z = Math.PI / 3; circle.position.x = -300; circle.position.y = 150; circle.position.z = -300; circle.castShadow = circle.receiveShadow = true; this.scene.add(circle); // add cube shape var cube = new THREE.Mesh(new THREE.CubeGeometry(100, 100, 100), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); cube.rotation.x = cube.rotation.z = Math.PI * 0.1; cube.position.x = -300; cube.position.y = 150; cube.position.z = -100; cube.castShadow = cube.receiveShadow = true; this.scene.add(cube); // add cylinder shape var cube = new THREE.Mesh(new THREE.CylinderGeometry(60, 80, 90, 32), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); cube.rotation.x = cube.rotation.z = Math.PI * 0.1; cube.position.x = -300; cube.position.y = 150; cube.position.z = 100; cube.castShadow = cube.receiveShadow = true; this.scene.add(cube); // add extrude geometry shape var extrudeSettings = { amount: 10, steps: 10, bevelSegments: 10, bevelSize: 10, bevelThickness: 10 }; var triangleShape = new THREE.Shape(); triangleShape.moveTo( 0, -50 ); triangleShape.lineTo( -50, 50 ); triangleShape.lineTo( 50, 50 ); triangleShape.lineTo( 0, -50 ); var extrude = new THREE.Mesh(new THREE.ExtrudeGeometry(triangleShape, extrudeSettings), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); extrude.rotation.y = Math.PI / 2; extrude.position.x = -300; extrude.position.y = 150; extrude.position.z = 300; extrude.castShadow = extrude.receiveShadow = true; this.scene.add(extrude); // add icosahedron shape var icosahedron = new THREE.Mesh(new THREE.IcosahedronGeometry(70), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); icosahedron.position.x = -100; icosahedron.position.y = 150; icosahedron.position.z = -300; icosahedron.castShadow = icosahedron.receiveShadow = true; this.scene.add(icosahedron); // add octahedron shape var octahedron = new THREE.Mesh(new THREE.OctahedronGeometry(70), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); octahedron.position.x = -100; octahedron.position.y = 150; octahedron.position.z = -100; octahedron.castShadow = octahedron.receiveShadow = true; this.scene.add(octahedron); // add ring shape var ring = new THREE.Mesh(new THREE.RingGeometry(30, 70, 32), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); ring.rotation.y = -Math.PI / 2; ring.position.x = -100; ring.position.y = 150; ring.position.z = 100; ring.castShadow = ring.receiveShadow = true; this.scene.add(ring); // add shape geometry shape var shapeG = new THREE.Mesh(new THREE.ShapeGeometry(triangleShape), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); shapeG.rotation.y = -Math.PI / 2; shapeG.position.x = -100; shapeG.position.y = 150; shapeG.position.z = 300; shapeG.castShadow = shapeG.receiveShadow = true; this.scene.add(shapeG); // add sphere shape var sphere = new THREE.Mesh(new THREE.SphereGeometry(70, 32, 32), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); sphere.rotation.y = -Math.PI / 2; sphere.position.x = 100; sphere.position.y = 150; sphere.position.z = -300; sphere.castShadow = sphere.receiveShadow = true; this.scene.add(sphere); // add tetrahedron shape var tetrahedron = new THREE.Mesh(new THREE.TetrahedronGeometry(70), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); tetrahedron.position.x = 100; tetrahedron.position.y = 150; tetrahedron.position.z = -100; tetrahedron.castShadow = tetrahedron.receiveShadow = true; this.scene.add(tetrahedron); // add torus shape var torus = new THREE.Mesh(new THREE.TorusGeometry(70, 20, 16, 100), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); torus.rotation.y = -Math.PI / 2; torus.position.x = 100; torus.position.y = 150; torus.position.z = 100; torus.castShadow = torus.receiveShadow = true; this.scene.add(torus); // add torus knot shape var torusK = new THREE.Mesh(new THREE.TorusKnotGeometry(70, 20, 16, 100), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); torusK.rotation.y = -Math.PI / 2; torusK.position.x = 100; torusK.position.y = 150; torusK.position.z = 300; torusK.castShadow = torusK.receiveShadow = true; this.scene.add(torusK); // add tube shape var points = []; for (var i = 0; i < 10; i++) { var randomX = -100 + Math.round(Math.random() * 200); var randomY = -100 + Math.round(Math.random() * 200); var randomZ = -100 + Math.round(Math.random() * 200); points.push(new THREE.Vector3(randomX, randomY, randomZ)); } var tube = new THREE.Mesh(new THREE.TubeGeometry(new THREE.SplineCurve3(points), 64, 20), new THREE.MeshLambertMaterial({ color: this.getRandColor() })); tube.rotation.y = -Math.PI / 2; tube.position.x = 0; tube.position.y = 500; tube.position.z = 0; tube.castShadow = tube.receiveShadow = true; this.scene.add(tube); }, getRandColor: function() { return colors[Math.floor(Math.random() * colors.length)]; } };
设置运动样式
为了顺利地将光,我们只需要在update方法里添加以下代码:// Update controls and stats function update() { lesson1.controls.update(lesson1.clock.getDelta()); lesson1.stats.update(); // smoothly move the particleLight var timer = Date.now() * 0.000025; particleLight.position.x = Math.sin(timer * 5) * 300; particleLight.position.z = Math.cos(timer * 5) * 300; }
结束
源码下载请关注我的微信公众号相关文章推荐
- [webGL学习]基于three.js构建WebGL实例第一讲
- [webGL学习]基于three.js构建WebGL实例第六讲
- [webGL学习]基于three.js构建WebGL实例第三讲
- [webGL学习]基于three.js构建WebGL实例第二讲
- [webGL学习]基于three.js构建WebGL实例讲解大纲
- [webGL学习]基于three.js构建WebGL实例第五讲
- [webGL学习]基于three.js构建WebGL实例第四讲
- webgl+three.js,学习笔记,画一个立方体+解析
- webgl+three.js,学习笔记,调用摄像头,做成纹理
- Three.js讲解以及WEBGL实例(转)
- Three.js讲解以及WEBGL实例
- 学习笔记Webgl之Three.js (1)
- Three.js讲解以及WEBGL实例
- Three.JS-学习 The WebGL earth (1)---globe.html 分析
- Three.JS提升学习2:构建Three.js场景的基本组件
- 学习 WebGL 的开源库 Three.js
- WebGL之ThreeJS学习之旅01
- 小八——WebGL心路历程(2),一个基于Three.js的webGL程序解析
- Three.js讲解以及WEBGL实例
- three.js学习笔记 基于物理引擎的第一人称控件