three.js(7)-几何体

作者: 姜治宇 | 来源:发表于2021-11-17 11:14 被阅读0次

three.js基础
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three.js(7)-几何体
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Three.js学习规划
Three.js笔记（十）几何体
threejs--初创项目
个人Three.js网页端项目展示
THREE.js_的使用(例子)
UG编程CAM教程，型腔铣Cavity_Mill几何体精讲

几何体其实就是由一系列的顶点组成，我们在坐标系打几个点看看：

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="http://www.yanhuangxueyuan.com/versions/threejsR92/build/three.js"></script>
</head>

<body>
    <div id="webgl"></div>
</body>

</html>
<script>
    var scene = new THREE.Scene();
    var axes = new THREE.AxesHelper(200);//50表示xyz轴的长度，红:x,绿:y,蓝:z
    scene.add(axes);//添加坐标轴
    var geometry = new THREE.BufferGeometry(); //创建一个Buffer类型几何体对象
    var vertices = new Float32Array([
        0, 0, 0, //顶点1坐标
        50, 0, 0, //顶点2坐标
        0, 100, 0, //顶点3坐标
        0, 0, 10, //顶点4坐标
        0, 0, 100, //顶点5坐标
        50, 0, 10, //顶点6坐标

    ]);
    //创建属性缓冲区对象
    var attr = new THREE.BufferAttribute(vertices, 3);//3个为一组，表示一个顶点的xyz坐标
    geometry.attributes.position = attr;

    // 点渲染模式
    var material = new THREE.PointsMaterial({
        color: 0xffff00,
        size: 10.0 //点对象像素尺寸
    }); //材质对象
    var points = new THREE.Points(geometry, material); //点模型对象
    scene.add(points); //点对象添加到场景中

    //创建相机对象
    var camera = new THREE.PerspectiveCamera(45, 2, 0.1, 2000);
    camera.position.set(300, 300, 100); //设置相机位置
    camera.lookAt(scene.position); //设置相机方向(指向的场景对象)


    /**
     * 创建渲染器对象
     */
    var renderer = new THREE.WebGLRenderer({
        antialias: true //消除锯齿
    });
    renderer.setSize(1000, 500);//设置渲染区域尺寸
    renderer.setClearColor(0xb9d3ff, 1); //设置背景颜色
    renderer.render(scene, camera);//渲染必须有场景和相机两个对象

    var cont = document.getElementById('webgl');
    cont.appendChild(renderer.domElement);
</script>

point.png

我们将顶点连起来：

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="http://www.yanhuangxueyuan.com/versions/threejsR92/build/three.js"></script>
</head>

<body>
    <div id="webgl"></div>
</body>

</html>
<script>
    var scene = new THREE.Scene();
    var axes = new THREE.AxesHelper(200);//50表示xyz轴的长度，红:x,绿:y,蓝:z
    scene.add(axes);//添加坐标轴
    var geometry = new THREE.BufferGeometry(); //创建一个Buffer类型几何体对象
    var vertices = new Float32Array([
        0, 0, 0, //顶点1坐标
        50, 0, 0, //顶点2坐标
        0, 100, 0, //顶点3坐标
        0, 0, 10, //顶点4坐标
        0, 0, 100, //顶点5坐标
        50, 0, 10, //顶点6坐标

    ]);
    //创建属性缓冲区对象
    var attr = new THREE.BufferAttribute(vertices, 3);//3个为一组，表示一个顶点的xyz坐标
    geometry.attributes.position = attr;

    // 线条渲染模式
    var material = new THREE.LineBasicMaterial({
        color: 0xffff00 //线条颜色
    });//材质对象
    var line = new THREE.Line(geometry, material);//线条模型对象
    scene.add(line);//线条对象添加到场景中

    //创建相机对象
    var camera = new THREE.PerspectiveCamera(45, 2, 0.1, 2000);
    camera.position.set(300, 300, 100); //设置相机位置
    camera.lookAt(scene.position); //设置相机方向(指向的场景对象)


    /**
     * 创建渲染器对象
     */
    var renderer = new THREE.WebGLRenderer({
        antialias: true //消除锯齿
    });
    renderer.setSize(1000, 500);//设置渲染区域尺寸
    renderer.setClearColor(0xb9d3ff, 1); //设置背景颜色
    renderer.render(scene, camera);//渲染必须有场景和相机两个对象

    var cont = document.getElementById('webgl');
    cont.appendChild(renderer.domElement);
</script>

line.png

如果将这些点连起来形成面：

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="http://www.yanhuangxueyuan.com/versions/threejsR92/build/three.js"></script>
</head>

<body>
    <div id="webgl"></div>
</body>

</html>
<script>
    var scene = new THREE.Scene();
    var axes = new THREE.AxesHelper(200);//50表示xyz轴的长度，红:x,绿:y,蓝:z
    scene.add(axes);//添加坐标轴
    var geometry = new THREE.BufferGeometry(); //创建一个Buffer类型几何体对象
    var vertices = new Float32Array([
        0, 0, 0, //顶点1坐标
        50, 0, 0, //顶点2坐标
        0, 100, 0, //顶点3坐标
        0, 0, 10, //顶点4坐标
        0, 0, 100, //顶点5坐标
        50, 0, 10, //顶点6坐标

    ]);
    //创建属性缓冲区对象
    var attr = new THREE.BufferAttribute(vertices, 3);//3个为一组，表示一个顶点的xyz坐标
    geometry.attributes.position = attr;
    // 三角面(网格)渲染模式
    var material = new THREE.PointsMaterial({
        color: 0xffff00, //三角面颜色
    }); //材质对象
    var mesh = new THREE.Mesh(geometry, material); //网格模型对象Mesh
    scene.add(mesh);
    //创建相机对象
    var camera = new THREE.PerspectiveCamera(45, 2, 0.1, 2000);
    camera.position.set(300,300, 100); //设置相机位置
    camera.lookAt(scene.position); //设置相机方向(指向的场景对象)


    /**
     * 创建渲染器对象
     */
    var renderer = new THREE.WebGLRenderer({
        antialias: true //消除锯齿
    });
    renderer.setSize(1000, 500);//设置渲染区域尺寸
    renderer.setClearColor(0xb9d3ff, 1); //设置背景颜色
    renderer.render(scene, camera);//渲染必须有场景和相机两个对象

    var cont = document.getElementById('webgl');
    cont.appendChild(renderer.domElement);
</script>

polygon.png