three.js,教程,three.js,three.js,网格前言 小编之前发布过关于几何形状和材质，相信大家看过学习之后，我们就能使用他们来创建物体了。最常用的一种物体就是网格（Mesh），网格是由顶点、边、面等组成的物体；其他物体包括线段（Line）、骨骼（Bone）、粒子系统（ParticleSystem）等。创建物体需要指定几何形状和材质，其中，几何形状决定了物体的顶点位置等信息，材质决定了物体的颜色、纹理等信息。 1.创建网格 在前几篇中，我们学习了如何创建几何形状与材质，而网格的创建非常简单，只要把几何形状与材质传入其构造函数。最常用的物体是网格（Mesh），它代表包含点、线、面的几何体，其构造函数是： 下面，让我们通过一个具体的例子了解如何创建网格：
var material = new THREE.MeshLambertMaterial({ color: 0xffff00});var geometry = new THREE.CubeGeometry(1, 2, 3);var mesh = new THREE.Mesh(geometry, material);scene.add(mesh); 如果material和geometry之后不会复用的话，也可以合在一起写为：
var mesh = new THREE.Mesh(new THREE.CubeGeometry(1, 2, 3), new THREE.MeshLambertMaterial({ color: 0xffff00 }));scene.add(mesh); 添加光照后，得到的效果为： 
如果不指定material，则每次会随机分配一种wireframe为true的材质，每次刷新页面后的颜色是不同的，一种可能的效果是： 
源码：
<!DOCTYPE html><html> <head> <meta charset="UTF-8"> <title>3.js测试9.1</title> </head> <body onload="init()"> <canvas id="mainCanvas" width="400px" height="300px" ></canvas> </body> <script type="text/javascript" src="js/three.min.js"></script> <script type="text/javascript"> function init() { var renderer = new THREE.WebGLRenderer({ canvas: document.getElementById('mainCanvas') }); renderer.setClearColor(0x000000); var scene = new THREE.Scene(); // camera var camera = new THREE.OrthographicCamera(-2.5, 2.5, 1.875, -1.875, 0.1, 100); camera.position.set(5, 5, 20); camera.lookAt(new THREE.Vector3(0, 0, 0)); scene.add(camera); var material = new THREE.MeshLambertMaterial({ color: 0xffff00 });// var material = new THREE.MeshBasicMaterial({// color: 0xffff00,// wireframe: true// }); var geometry = new THREE.CubeGeometry(1, 2, 3); var mesh = new THREE.Mesh(geometry, material); scene.add(mesh); var light = new THREE.DirectionalLight(0xffffff); light.position.set(20, 10, 5); scene.add(light); // render renderer.render(scene, camera); } </script></html> 2.修改属性 2.1 修改材质 除了在构造函数中指定材质，在网格被创建后，也能对材质进行修改：
var material = new THREE.MeshLambertMaterial({ color: 0xffff00});var geometry = new THREE.CubeGeometry(1, 2, 3);var mesh = new THREE.Mesh(geometry, material); scene.add(mesh);mesh.material = new THREE.MeshLambertMaterial({ color: 0xff0000}); 最终显示的颜色是红色： 
源码：
<!DOCTYPE html><html> <head> <meta charset="UTF-8"> <title>3.js测试9.2</title> </head> <body onload="init()"> <canvas id="mainCanvas" width="400px" height="300px" ></canvas> </body> <script type="text/javascript" src="js/three.min.js"></script> <script type="text/javascript"> function init() { var renderer = new THREE.WebGLRenderer({ canvas: document.getElementById('mainCanvas') }); renderer.setClearColor(0x000000); var scene = new THREE.Scene(); // camera var camera = new THREE.OrthographicCamera(-2.5, 2.5, 1.875, -1.875, 0.1, 100); camera.position.set(5, 5, 20); camera.lookAt(new THREE.Vector3(0, 0, 0)); scene.add(camera); var material = new THREE.MeshLambertMaterial({ color: 0xffff00 }); var geometry = new THREE.CubeGeometry(1, 2, 3); var mesh = new THREE.Mesh(geometry, material); scene.add(mesh); mesh.material = new THREE.MeshLambertMaterial({ color: 0xff0000 }); var light = new THREE.DirectionalLight(0xffffff); light.position.set(20, 10, 5); scene.add(light); // render renderer.render(scene, camera); } </script></html> 2.2 位置、缩放、旋转 位置、缩放、旋转是物体三个常用属性。由于THREE.Mesh基础自THREE.Object3D，因此包含scale、rotation、position三个属性。它们都是THREE.Vector3实例，因此修改其值的方法是相同的，这里以位置为例。 THREE.Vector3有x、y、z三个属性，如果只设置其中一个属性，则可以用以下方法： 如果需要同时设置多个属性，可以使用以下两种方法： mesh.position.set(1.5, -0.5, 0); 或者： mesh.position = new THREE.Vector3(1.5, -0.5, 0); 缩放对应的属性是scale，旋转对应的属性是rotation，具体方法与上例相同，分别表示沿x、y、z三轴缩放或旋转。  源码：
<!DOCTYPE html><html> <head> <meta charset="UTF-8"> <title>3.js测试9.3</title> </head> <body onload="init()"> <canvas id="mainCanvas" width="400px" height="300px" ></canvas> </body> <script type="text/javascript" src="js/three.min.js"></script> <script type="text/javascript"> function init() { var renderer = new THREE.WebGLRenderer({ canvas: document.getElementById('mainCanvas') }); renderer.setClearColor(0x000000); var scene = new THREE.Scene(); // camera var camera = new THREE.OrthographicCamera(-2.5, 2.5, 1.875, -1.875, 0.1, 100); camera.position.set(5, 5, 20); camera.lookAt(new THREE.Vector3(0, 0, 0)); scene.add(camera); var material = new THREE.MeshLambertMaterial({ color: 0xffff00 }); var geometry = new THREE.CubeGeometry(1, 2, 3); var mesh = new THREE.Mesh(geometry, material); scene.add(mesh); mesh.position.set(1.5, -0.5, 0); mesh.position = new THREE.Vector3(1.5, -0.5, 0); mesh.position.z = 1; var light = new THREE.DirectionalLight(0xffffff); light.position.set(20, 10, 5); scene.add(light); drawAxes(scene); // render renderer.render(scene, camera); } function drawAxes(scene) { // x-axis var xGeo = new THREE.Geometry(); xGeo.vertices.push(new THREE.Vector3(0, 0, 0)); xGeo.vertices.push(new THREE.Vector3(1, 0, 0)); var xMat = new THREE.LineBasicMaterial({ color: 0xff0000 }); var xAxis = new THREE.Line(xGeo, xMat); scene.add(xAxis); // y-axis var yGeo = new THREE.Geometry(); yGeo.vertices.push(new THREE.Vector3(0, 0, 0)); yGeo.vertices.push(new THREE.Vector3(0, 1, 0)); var yMat = new THREE.LineBasicMaterial({ color: 0x00ff00 }); var yAxis = new THREE.Line(yGeo, yMat); scene.add(yAxis); // z-axis var zGeo = new THREE.Geometry(); zGeo.vertices.push(new THREE.Vector3(0, 0, 0)); zGeo.vertices.push(new THREE.Vector3(0, 0, 1)); var zMat = new THREE.LineBasicMaterial({ color: 0x00ccff }); var zAxis = new THREE.Line(zGeo, zMat); scene.add(zAxis); } </script></html>本文的内容到这就结束了，文章通过详细实例及图片介绍了Three.js中的网格，希望本文对大家学习Three.js有所帮助。
three.js,教程,three.js,three.js,网格
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