package vectorimport (    "math"    "fmt")// 三维向量：(x,y,z)type Vector3 struct {    X float64    `json:"x"`    Y float64    `json:"y"`    Z float64    `json:"z"`}func (this *Vector3)Equal(v Vector3) bool {    return this.X == v.X && this.Y == v.Y && this.Z == v.Z}// 三维向量：设值func (this *Vector3)Set(x, y, z float64) {    this.X = x    this.Y = y    this.Z = z}// 三维向量：拷贝func (this *Vector3)Clone() Vector3 {    return NewVector3(this.X, this.Y, this.Z)}// 三维向量：加上// this = this + vfunc (this *Vector3)Add(v Vector3) {    this.X += v.X    this.Y += v.Y    this.Z += v.Z}// 三维向量：减去// this = this - vfunc (this *Vector3)Sub(v Vector3) {    this.X -= v.X    this.Y -= v.Y    this.Z -= v.Z}// 三维向量：数乘func (this *Vector3)Multiply(scalar float64) {    this.X *= scalar    this.Y *= scalar    this.Z *= scalar}func (this *Vector3)Divide(scalar float64) {    if scalar == 0 {        panic("分母不能为零！")    }    this.Multiply(1 / scalar)}// 三维向量：点积func (this *Vector3)Dot(v Vector3) float64 {    return this.X * v.X + this.Y * v.Y + this.Z * v.Z}// 三维向量：叉积func (this *Vector3)Cross(v Vector3) {    x, y, z := this.X, this.Y, this.Z    this.X = y * v.Z - z * v.Y;    this.Y = z * v.X - x * v.Z;    this.Z = x * v.Y - y * v.X;}// 三维向量：长度func (this *Vector3)Length() float64 {    return math.Sqrt(this.X * this.X + this.Y * this.Y + this.Z * this.Z)}// 三维向量：长度平方func (this *Vector3)LengthSq() float64 {    return this.X * this.X + this.Y * this.Y + this.Z * this.Z}// 三维向量：单位化func (this *Vector3)Normalize() {    this.Divide(this.Length())}// 返回：新向量func NewVector3(x, y, z float64) Vector3 {    return Vector3{X:x, Y:y, Z:z}}// 返回：零向量(0,0,0)func Zero3() Vector3 {    return Vector3{X:0, Y:0, Z:0}}// X 轴 单位向量func XAxis3() Vector3 {    return Vector3{X:1, Y:0, Z:0}}// Y 轴 单位向量func YAxis3() Vector3 {    return Vector3{X:0, Y:1, Z:0}}// Z 轴 单位向量func ZAxis3() Vector3 {    return Vector3{X:0, Y:0, Z:1}}func XYAxis3() Vector3 {    return Vector3{X:1, Y:1, Z:0}}func XZAxis3() Vector3 {    return Vector3{X:1, Y:0, Z:1}}func YZAxis3() Vector3 {    return Vector3{X:0, Y:1, Z:1}}func XYZAxis3() Vector3 {    return Vector3{X:1, Y:1, Z:1}}// 返回：a + b 向量func Add3(a, b Vector3) Vector3 {    return Vector3{X:a.X + b.X, Y:a.Y + b.Y, Z:a.Z + b.Z}}// 返回：a - b 向量func Sub3(a, b Vector3) Vector3 {    return Vector3{X:a.X - b.X, Y:a.Y - b.Y, Z:a.Z - b.Z}}// 返回：a X b 向量 (X 叉乘)func Cross3(a, b Vector3) Vector3 {    return Vector3{X:a.Y * b.Z - a.Z * b.Y, Y:a.Z * b.X - a.X * b.Z, Z:a.X * b.Y - a.Y * b.X}}func AddArray3(vs []Vector3, dv Vector3) []Vector3 {    for i,_ := range vs {        vs[i].Add(dv)    }    return vs}func Multiply3(v Vector3,scalars []float64) []Vector3 {    vs := []Vector3{}    for _,value := range scalars {        vector := v.Clone()        vector.Multiply(value)        vs = append(vs, vector)    }    return vs}// 返回：单位化向量func Normalize3(a Vector3) Vector3 {    b := a.Clone()    b.Normalize()    return b}//求两点间距离func GetDistance(a Vector3,b Vector3) float64{    return math.Sqrt(math.Pow(a.X - b.X, 2) + math.Pow(a.Y - b.Y, 2) + math.Pow(a.Z - b.Z, 2))}