three.js 源码注释（十三）Math/Ray.js

商域无疆 (http://blog.csdn.net/omni360/)

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俺也是刚开始学,好多地儿肯定不对还请见谅.

以下代码是THREE.JS 源码文件中Math/Ray.js文件的注释.

更多更新在 : https://github.com/omni360/three.js.sourcecode/blob/master/Three.js

今天把Three.js的Ray类注释完了,非常重要的一个类.在场景中拾取对象,经常会用到这个类.

// File:src/math/Ray.js/** * @author bhouston / http://exocortex.com *//*///Ray对象的构造函数.用来创建一个三维空间里的射线对象.Ray对象的功能函数采用///定义构造的函数原型对象来实现,ray主要是用来进行碰撞检测,在选择场景中的对象时经常会用到,判断当前鼠标是否与对象重合用来选择对象.//////用法: var origin = new Vector3(1,1,1),direction = new Vector3(9,9,9); var ray = new Ray(origin,direction);///创建一个原点为origin,方向为direction的射线.*////<summary>Ray</summary>///<param name ="origin" type="Vector3">射线的端点,Vector3对象</param>///<param name ="direction" type="Vector3">射线的方向,Vector3对象</param>THREE.Ray = function ( origin, direction ) {this.origin = ( origin !== undefined ) ? origin : new THREE.Vector3();this.direction = ( direction !== undefined ) ? direction : new THREE.Vector3();};/********************************************下面是Vector3对象提供的功能函数.****************************************/THREE.Ray.prototype = {constructor: THREE.Ray,//构造器,返回对创建此对象的Ray函数的引用/*///set方法用来从新设置射线的端点和方向(origin,direction).并返回新的射线.*////<summary>set</summary>///<param name ="origin" type="Vector3">x坐标</param>///<param name ="direction" type="Vector3">y坐标</param>///<returns type="Ray">返回新的射线</returns>set: function ( origin, direction ) {this.origin.copy( origin );this.direction.copy( direction );return this;//返回新的射线},/*///copy方法用来复制射线的端点,方向,origin,direction坐标值.并返回新的坐标值的射线.*////<summary>copy</summary>///<param name ="ray" type="Ray">射线</param>///<returns type="Ray">返回新坐标值的射线</returns>copy: function ( ray ) {this.origin.copy( ray.origin );this.direction.copy( ray.direction );return this;//返回新坐标值的射线},/*///at方法将返回沿当前射线方向的从端点起长度为t的点.如果传入了optionalTarget参数,将结果保存到optionalTarget中./// NOTE:optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象*////<summary>at</summary>///<param name ="t" type="Number">数值,到端点的长度</param>///<param name ="optionalTarget" type="Vector3">optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象</param>///<returns type="Ray">返回沿当前射线方向的从端点起长度为t的点/returns>at: function ( t, optionalTarget ) {var result = optionalTarget || new THREE.Vector3();return result.copy( this.direction ).multiplyScalar( t ).add( this.origin );//将返回沿当前射线方向的从端点起长度为t的点},/*///recast方法将调用at(t)方法返回沿当前射线方向的从端点起长度为t的点,并将范围的点设为端点.*////<summary>recast</summary>///<param name ="t" type="Number">数值,到端点的长度</param>///<returns type="Ray">返回新端点的射线/returns>recast: function () {var v1 = new THREE.Vector3();return function ( t ) {this.origin.copy( this.at( t, v1 ) );//调用at(t)方法返回沿当前射线方向的从端点起长度为t的点,并将范围的点设为端点.return this;//返回新端点的射线};}(),/*///closestPointToPoint方法将返回任意点point到射线上的垂足.如果传入了optionalTarget参数,将结果保存到optionalTarget中./// NOTE:optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象/// NOTE:注意closestPointToPoint()方法定义如果垂足不在射线上,返回原点.*////<summary>closestPointToPoint</summary>///<param name ="point" type="Vector3">任意点Vector3对象</param>///<param name ="optionalTarget" type="Vector3">optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象</param>///<returns type="Ray">返回任意点point到射线上的垂足/returns>closestPointToPoint: function ( point, optionalTarget ) {var result = optionalTarget || new THREE.Vector3();result.subVectors( point, this.origin );var directionDistance = result.dot( this.direction );//调用dot方法返回两个向量的点积,并赋值给directionDistance.if ( directionDistance < 0 ) {//如果directionDistance小于0,表示垂足不在射线上,return result.copy( this.origin );//返回原点}return result.copy( this.direction ).multiplyScalar( directionDistance ).add( this.origin );//返回任意点point到射线上的垂足},/*///distanceToPoint方法将返回任意点到该射线的距离./// NOTE:注意distanceToPoint()方法定义如果传入的参数point在端点后面,返回端点到该点的距离.*////<summary>distanceToPoint</summary>///<param name ="point" type="Vector3">任意点Vector3对象</param>///<returns type="Number">返回任意点point到射线的距离或到射线端点的距离./returns>distanceToPoint: function () {var v1 = new THREE.Vector3();return function ( point ) {var directionDistance = v1.subVectors( point, this.origin ).dot( this.direction );//调用dot方法返回两个向量的点积,并赋值给directionDistance.// point behind the ray// 判断端点是否在端点后面if ( directionDistance < 0 ) {//如果directionDistance小于0,表示参数point在射线端点后面return this.origin.distanceTo( point );//返回端点到该点的距离}v1.copy( this.direction ).multiplyScalar( directionDistance ).add( this.origin );//如果参数point在射线端点前面,return v1.distanceTo( point );//返回该点到射线的距离,即到垂足的距离.};}(),/*///distanceSqToSegment方法将返回有参数v0,v1组成的线段到当前射线的最小距离.可选参数optionalPointOnRay, optionalPointOnSegment,分别用来存储在射线上和在线段上的垂足.*////<summary>distanceToPoint</summary>///<param name ="v0" type="Vector3">任意点Vector3对象</param>///<param name ="v1" type="Vector3">任意点Vector3对象</param>///<param name ="optionalPointOnRay" type="Vector3">optionalPointOnRay是可选参数,如果没有设置,系统自动创建一个临时Vector3对象,用来存储在射线上的垂足</param>///<param name ="optionalPointOnSegment" type="Vector3">optionalPointOnSegment是可选参数,如果没有设置,系统自动创建一个临时Vector3对象,用来存储在线段上的垂足</param>///<returns type="Number">返回任意点point到射线的距离或到射线端点的距离./returns>distanceSqToSegment: function ( v0, v1, optionalPointOnRay, optionalPointOnSegment ) {// from http://www.geometrictools.com/LibMathematics/Distance/Wm5DistRay3Segment3.cpp// It returns the min distance between the ray and the segment// distanceSqToSegment()方法返回线段到当前射线的最小距离// defined by v0 and v1// 线段由v0,v1构成// It can also set two optional targets :// 可一传递两个可选参数optionalPointOnRay, optionalPointOnSegment// - The closest point on the ray// 参数optionalPointOnRay用来存储在射线上的垂足// - The closest point on the segment// 参数optionalPointOnSegment用来存储在线段上的垂足var segCenter = v0.clone().add( v1 ).multiplyScalar( 0.5 );//获得线段的中点var segDir = v1.clone().sub( v0 ).normalize();//获得线段的单位向量,var segExtent = v0.distanceTo( v1 ) * 0.5;//线段的长度的一半?var diff = this.origin.clone().sub( segCenter );//var a01 = - this.direction.dot( segDir );var b0 = diff.dot( this.direction );var b1 = - diff.dot( segDir );var c = diff.lengthSq();var det = Math.abs( 1 - a01 * a01 );var s0, s1, sqrDist, extDet;if ( det >= 0 ) {// The ray and segment are not parallel.// 线段和射线不平行s0 = a01 * b1 - b0;s1 = a01 * b0 - b1;extDet = segExtent * det;if ( s0 >= 0 ) {if ( s1 >= - extDet ) {if ( s1 <= extDet ) {// region 0// Minimum at interior points of ray and segment.var invDet = 1 / det;s0 *= invDet;s1 *= invDet;sqrDist = s0 * ( s0 + a01 * s1 + 2 * b0 ) + s1 * ( a01 * s0 + s1 + 2 * b1 ) + c;} else {// region 1s1 = segExtent;s0 = Math.max( 0, - ( a01 * s1 + b0 ) );sqrDist = - s0 * s0 + s1 * ( s1 + 2 * b1 ) + c;}} else {// region 5s1 = - segExtent;s0 = Math.max( 0, - ( a01 * s1 + b0 ) );sqrDist = - s0 * s0 + s1 * ( s1 + 2 * b1 ) + c;}} else {if ( s1 <= - extDet ) {// region 4s0 = Math.max( 0, - ( - a01 * segExtent + b0 ) );s1 = ( s0 > 0 ) ? - segExtent : Math.min( Math.max( - segExtent, - b1 ), segExtent );sqrDist = - s0 * s0 + s1 * ( s1 + 2 * b1 ) + c;} else if ( s1 <= extDet ) {// region 3s0 = 0;s1 = Math.min( Math.max( - segExtent, - b1 ), segExtent );sqrDist = s1 * ( s1 + 2 * b1 ) + c;} else {// region 2s0 = Math.max( 0, - ( a01 * segExtent + b0 ) );s1 = ( s0 > 0 ) ? segExtent : Math.min( Math.max( - segExtent, - b1 ), segExtent );sqrDist = - s0 * s0 + s1 * ( s1 + 2 * b1 ) + c;}}} else {// Ray and segment are parallel.// 线段和射线平行s1 = ( a01 > 0 ) ? - segExtent : segExtent;s0 = Math.max( 0, - ( a01 * s1 + b0 ) );sqrDist = - s0 * s0 + s1 * ( s1 + 2 * b1 ) + c;}if ( optionalPointOnRay ) {optionalPointOnRay.copy( this.direction.clone().multiplyScalar( s0 ).add( this.origin ) );}if ( optionalPointOnSegment ) {optionalPointOnSegment.copy( segDir.clone().multiplyScalar( s1 ).add( segCenter ) );}return sqrDist;//返回最小长度.},/*///isIntersectionSphere方法用来判断当前射线是否与参数sphere球体相交相交./// NOTE:isIntersectionSphere方法要求Sphere球体对象,必须有radius和center属性,sphereGeometry无效*////<summary>isIntersectionSphere</summary>///<param name ="sphere" type="Sphere">Sphere球体对象,必须有radius和center属性,sphereGeometry无效</param>///<returns type="Boolean">返回true 或者 false</returns>isIntersectionSphere: function ( sphere ) {return this.distanceToPoint( sphere.center ) <= sphere.radius;//返回true 或者 false},/*///intersectSphere方法用来判断当前射线是否与参数sphere球体相交,如果相交返回交点.如果不想交返回null/// NOTE:intersectSphere方法要求Sphere球体对象,必须有radius和center属性,sphereGeometry无效/// NOTE:intersectSphere方法经常用在鼠标拾取球体*////<summary>intersectSphere</summary>///<param name ="sphere" type="Sphere">Sphere球体对象,必须有radius和center属性,sphereGeometry无效</param>///<param name ="optionalTarget" type="Vector3">optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象,用来存储射线与球体的交点</param>///<returns type="Boolean">如果相交返回交点.如果不想交返回null</returns>intersectSphere: function () {// from http://www.scratchapixel.com/lessons/3d-basic-lessons/lesson-7-intersecting-simple-shapes/ray-sphere-intersection/var v1 = new THREE.Vector3();return function ( sphere, optionalTarget ) {v1.subVectors( sphere.center, this.origin );var tca = v1.dot( this.direction );var d2 = v1.dot( v1 ) - tca * tca;var radius2 = sphere.radius * sphere.radius;if ( d2 > radius2 ) return null;//如果不相交返回nullvar thc = Math.sqrt( radius2 - d2 );// t0 = first intersect point - entrance on front of sphere // t0射线与球体的第一个交点,从球体的前面进入var t0 = tca - thc;// t1 = second intersect point - exit point on back of sphere// t1射线与球体的第二个交点,从球体的背面射出var t1 = tca + thc;// test to see if both t0 and t1 are behind the ray - if so, return null// 如果t0,t1都小于0,说明球体在射线端点的后面,返回null.if ( t0 < 0 && t1 < 0 ) return null;// test to see if t0 is behind the ray:// 如果t0射线与球体的第一个交点在射线端点的后面,// if it is, the ray is inside the sphere, so return the second exit point scaled by t1,// 说明射线端点在球体的内部,所以返回射线与球体表面的交点是t1,从球体的背面射出的交点.// in order to always return an intersect point that is in front of the ray.// 一般情况下总是返回一个交点,这里返回的是从球体的背面射出的交点.if ( t0 < 0 ) return this.at( t1, optionalTarget );// else t0 is in front of the ray, so return the first collision point scaled by t0 // 另一种情况,球体在射线的前面,返回t0,射线从球体体正面射入的交点.return this.at( t0, optionalTarget );}}(),/*///isIntersectionPlane方法用来判断当前射线是否与参数Plane平面相交,经常用来判断用户是否选中了场景中的平面./// NOTE:isIntersectionPlane方法要求Plane平面对象,必须有normal属性*////<summary>isIntersectionPlane</summary>///<param name ="plane" type="Plane">Plane平面对象,必须有normal属性</param>///<returns type="Boolean">返回true 或者 false</returns>isIntersectionPlane: function ( plane ) {// check if the ray lies on the plane first// 检查射线原点是否在Plane平面上,var distToPoint = plane.distanceToPoint( this.origin );//获得平面到射线原点(就是鼠标所在位置)的距离if ( distToPoint === 0 ) {//如果在平面上return true;//返回true}var denominator = plane.normal.dot( this.direction );//调用normal.dot方法获得射线到平面法线的单位向量,并赋值给denominatorif ( denominator * distToPoint < 0 ) {//原点到平面的距离乘以单位向量小于0,说明平面在射线的前面.return true;//返回true}// ray origin is behind the plane (and is pointing behind it)// 射线原点在Plane平面的后面,return false;//返回false},/*///distanceToPlane方法将返回参数plane平面到当前射线的最小距离./// NOTE:distanceToPlane方法要求Plane平面对象,必须有normal属性*////<summary>distanceToPlane</summary>///<param name ="plane" type="Plane">Plane平面对象,必须有normal属性</param>///<returns type="Number">返回任意点point到射线的距离或到射线端点的距离t,如果射线在当前平面上返回0.射线与平面永不相交或其他未知定义返回null</returns>distanceToPlane: function ( plane ) {var denominator = plane.normal.dot( this.direction );if ( denominator == 0 ) {// line is coplanar, return origin// 射线和平面共面,返回原点0.if ( plane.distanceToPoint( this.origin ) == 0 ) {return 0;//如果射线在当前平面上返回0}// Null is preferable to undefined since undefined means.... it is undefined// 其他未知定义返回nullreturn null;//其他未知定义返回null}var t = - ( this.origin.dot( plane.normal ) + plane.constant ) / denominator;// Return if the ray never intersects the plane// 射线与平面永不相交返回nullreturn t >= 0 ? t :  null;//射线与平面永不相交返回null,或者返回距离t},/*///intersectPlane方法用来判断当前射线是否与参数plane平面相交,如果相交返回交点.如果不想交返回null/// NOTE:intersectSphere方法要求plane平面对象,必须有normal属性/// NOTE:intersectSphere方法经常用在鼠标拾取plane平面*////<summary>intersectPlane</summary>///<param name ="plane" type="Plane">Plane平面对象,必须有normal属性</param>///<param name ="optionalTarget" type="Vector3">optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象,用来存储射线与平面的交点</param>///<returns type="Boolean">如果相交返回交点.如果射线与平面永不相交或其他未知定义返回null</returns>intersectPlane: function ( plane, optionalTarget ) {var t = this.distanceToPlane( plane );//调用distanceToPlane方法将返回参数plane平面到当前射线的最小距离if ( t === null ) {//如果射线与平面永不相交或其他未知定义返回nullreturn null;//返回null}return this.at( t, optionalTarget );//如果相交返回交点},/*///isIntersectionBox方法用来判断当前射线是否与参数Box立方体相交,经常用来判断用户是否选中了场景中的Box立方体对象./// NOTE:isIntersectionPlane方法要求Box立方体对象,必须有min,max属性*////<summary>isIntersectionBox</summary>///<param name ="box" type="Box3">Box立方体对象,必须有min,max属性</param>///<returns type="Boolean">返回true 或者 false</returns>isIntersectionBox: function () {var v = new THREE.Vector3();return function ( box ) {return this.intersectBox( box, v ) !== null; //调用intersectBox()方法,判断是否不等于null,返回true 或者 false};}(),/*///intersectBox方法用来判断当前射线是否与参数Box立方体相交,如果相交返回交点.如果不想交返回null/// NOTE:intersectBox方法要求Box立方体对象,必须有min,max属性/// NOTE:intersectBox方法经常用在鼠标拾取Box立方体*////<summary>intersectBox</summary>///<param name ="box" type="Box3">Box立方体对象,必须有min,max属性</param>///<param name ="optionalTarget" type="Vector3">optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象,用来存储射线与立方体的交点</param>///<returns type="Boolean">如果相交返回交点.如果射线与Box立方体永不相交或其他未知定义返回null</returns>intersectBox: function ( box , optionalTarget ) {// http://www.scratchapixel.com/lessons/3d-basic-lessons/lesson-7-intersecting-simple-shapes/ray-box-intersection/var tmin,tmax,tymin,tymax,tzmin,tzmax;var invdirx = 1 / this.direction.x,invdiry = 1 / this.direction.y,invdirz = 1 / this.direction.z;var origin = this.origin;//下面的这些是判断射线的原点在立方体的前后左右,还是立方体内,还是永不相交.如果射线原点在立方体后面或者不相交,返回nullif ( invdirx >= 0 ) {tmin = ( box.min.x - origin.x ) * invdirx;tmax = ( box.max.x - origin.x ) * invdirx;} else {tmin = ( box.max.x - origin.x ) * invdirx;tmax = ( box.min.x - origin.x ) * invdirx;}if ( invdiry >= 0 ) {tymin = ( box.min.y - origin.y ) * invdiry;tymax = ( box.max.y - origin.y ) * invdiry;} else {tymin = ( box.max.y - origin.y ) * invdiry;tymax = ( box.min.y - origin.y ) * invdiry;}if ( ( tmin > tymax ) || ( tymin > tmax ) ) return null;// These lines also handle the case where tmin or tmax is NaN// (result of 0 * Infinity). x !== x returns true if x is NaNif ( tymin > tmin || tmin !== tmin ) tmin = tymin;if ( tymax < tmax || tmax !== tmax ) tmax = tymax;if ( invdirz >= 0 ) {tzmin = ( box.min.z - origin.z ) * invdirz;tzmax = ( box.max.z - origin.z ) * invdirz;} else {tzmin = ( box.max.z - origin.z ) * invdirz;tzmax = ( box.min.z - origin.z ) * invdirz;}if ( ( tmin > tzmax ) || ( tzmin > tmax ) ) return null;if ( tzmin > tmin || tmin !== tmin ) tmin = tzmin;if ( tzmax < tmax || tmax !== tmax ) tmax = tzmax;//return point closest to the ray (positive side)//返回射线到立方体的垂足(正面的).if ( tmax < 0 ) return null;return this.at( tmin >= 0 ? tmin : tmax, optionalTarget );//返回交点并设置给可选参数optionalTarget},/*///intersectTriangle方法用来判断当前射线是否与参数a,b,c组成的Triangle三角形对象相交,如果相交返回交点.如果不想交返回null/// NOTE:intersectTriangle方法要求Box立方体对象,必须有min,max属性/// NOTE:intersectTriangle方法经常用在鼠标拾取Triangle三角形/// NOTE:可以参考博客http://www.cnblogs.com/graphics/archive/2010/08/09/1795348.html*////<summary>intersectTriangle</summary>///<param name ="a" type="Vector3">Triangle三角形的角点a</param>///<param name ="b" type="Vector3">Triangle三角形的角点b</param>///<param name ="c" type="Vector3">Triangle三角形的角点c</param>///<param name ="backfaceCulling" type="Boolean">true 或者 false,用来表示是否选择背面</param>///<param name ="optionalTarget" type="Vector3">optionalTarget是可选参数,如果没有设置,系统自动创建一个临时Vector3对象,用来存储射线与立方体的交点</param>///<returns type="Boolean">如果相交返回交点.如果射线与Triangle三角形永不相交或其他未知定义返回null</returns>intersectTriangle: function () {// Compute the offset origin, edges, and normal.var diff = new THREE.Vector3();var edge1 = new THREE.Vector3();var edge2 = new THREE.Vector3();var normal = new THREE.Vector3();return function ( a, b, c, backfaceCulling, optionalTarget ) {// from http://www.geometrictools.com/LibMathematics/Intersection/Wm5IntrRay3Triangle3.cppedge1.subVectors( b, a );edge2.subVectors( c, a );normal.crossVectors( edge1, edge2 );// Solve Q + t*D = b1*E1 + b2*E2 (Q = kDiff, D = ray direction,// E1 = kEdge1, E2 = kEdge2, N = Cross(E1,E2)) by//   |Dot(D,N)|*b1 = sign(Dot(D,N))*Dot(D,Cross(Q,E2))//   |Dot(D,N)|*b2 = sign(Dot(D,N))*Dot(D,Cross(E1,Q))//   |Dot(D,N)|*t = -sign(Dot(D,N))*Dot(Q,N)var DdN = this.direction.dot( normal );var sign;//下面的这些是判断射线的原点在Triangle三角形的前后左右,还是立方体内,还是永不相交.如果射线原点在立方体后面或者不相交,返回nullif ( DdN > 0 ) {if ( backfaceCulling ) return null;sign = 1;} else if ( DdN < 0 ) {sign = - 1;DdN = - DdN;} else {return null;}diff.subVectors( this.origin, a );var DdQxE2 = sign * this.direction.dot( edge2.crossVectors( diff, edge2 ) );// b1 < 0, no intersection// b1 <0 ,不相交if ( DdQxE2 < 0 ) {return null;}var DdE1xQ = sign * this.direction.dot( edge1.cross( diff ) );// b2 < 0, no intersection// b2 <0 ,不相交if ( DdE1xQ < 0 ) {return null;}// b1+b2 > 1, no intersection// b1+b2 > 1 ,不相交if ( DdQxE2 + DdE1xQ > DdN ) {return null;}// Line intersects triangle, check if ray does.// 射线与三角形相交var QdN = - sign * diff.dot( normal );// t < 0, no intersection// t < 0, 不相交if ( QdN < 0 ) {return null;}// Ray intersects triangle.// 射线与三角形相交.return this.at( QdN / DdN, optionalTarget );//返回交点.};}(),/*///applyMatrix4方法通过传递参数matrix4(旋转,缩放,移动等变换矩阵)对当前射线对象的原点及方向矢量,应用变换.*////<summary>applyMatrix4</summary>///<param name ="matrix4" type="Matrix4">(旋转,缩放,移动等变换矩阵</param>///<returns type="Boolean">返回变换后的射线对象.</returns>applyMatrix4: function ( matrix4 ) {this.direction.add( this.origin ).applyMatrix4( matrix4 );//对射线的方向矢量应用变换this.origin.applyMatrix4( matrix4 );//对射线的原点应用变换this.direction.sub( this.origin );this.direction.normalize();return this;//返回变换后的射线对象},/*equals方法///equals方法相当于比较运算符===,将当前射线和参数ray中的(origin,direction)值进行对比,返回bool型值.*////<summary>equals</summary>///<param name ="ray" type="Ray">射线(origin,direction)</param>///<returns type="bool">返回true or false</returns>equals: function ( ray ) {return ray.origin.equals( this.origin ) && ray.direction.equals( this.direction );//返回true or false},/*clone方法///clone方法克隆一个射线对象.*////<summary>clone</summary>///<returns type="Ray">返回射线对象</returns>clone: function () {return new THREE.Ray().copy( this );//返回射线对象}};

商域无疆 (http://blog.csdn.net/omni360/)

本文遵循“署名-非商业用途-保持一致”创作公用协议

转载请保留此句：商域无疆 -  本博客专注于 敏捷开发及移动和物联设备研究：数据可视化、GOLANG、Html5、WEBGL、THREE.JS，否则，出自本博客的文章拒绝转载或再转载，谢谢合作。

以下代码是THREE.JS 源码文件中Math/Ray.js文件的注释.

更多更新在 : https://github.com/omni360/three.js.sourcecode/blob/master/Three.js