Question

来自THREEjs.org/docs提供的示例：

var geometry = new THREE.Geometry();

geometry.vertices.push(
    new THREE.Vector3( -10,  10, 0 ),
    new THREE.Vector3( -10, -10, 0 ),
    new THREE.Vector3(  10, -10, 0 )
);

geometry.faces.push( new THREE.Face3( 0, 1, 2 ) );

geometry.computeBoundingSphere();

通过指定三角形的顶点可以非常直接地创建三角形。如果我想继续使用这种方法制作一个四面体，我发现自己重复这个代码三次，一次为四面体的每个面，每次改变一个向量来定义构成四面体的三角形之一...

有没有一种简单的方法，如果我定义四面体的第四个向量，创建一个四面体而不必单独定义每个面？

类似的东西：

var geometry = new THREE.Geometry();

geometry.vertices.push(
    new THREE.Vector3( -10,  10, 0 ),
    new THREE.Vector3( -10, -10, 0 ),
    new THREE.Vector3(  10, -10, 0 ),
    new THREE.Vector3(  10, 10, 10 ),
);

geometry.faces.push( new THREE.Face3( 0, 1, 2 ) );

geometry.computeBoundingSphere();

var mesh = new THREE.Mesh( geometry, material );
scene.add( mesh )

当然这段代码不起作用，最后一个顶点被忽略了。

Answer 1

在three.js的代码中查看src / extras / geometry / TetrahedronGeometry.js

复制此处的代码以供参考：

THREE.TetrahedronGeometry = function ( radius, detail ) {

    var vertices = [ 1,  1,  1,   - 1, - 1,  1,   - 1,  1, - 1,    1, - 1, - 1];
    var indices = [ 2,  1,  0,    0,  3,  2,    1,  3,  0,    2,  3,  1];

    THREE.PolyhedronGeometry.call( this, vertices, indices, radius, detail );
};

THREE.TetrahedronGeometry.prototype = Object.create( THREE.Geometry.prototype );

使用THREE.geometry的简单四面体

1 个答案: