vecks/src/V3.js

2D and 3D Vector Algebra library

class V3 {
  constructor (x, y, z) {
    if (typeof x === 'object') {
      this.x = x.x
      this.y = x.y
      this.z = x.z
    } else if (x === undefined) {
      this.x = 0
      this.y = 0
      this.z = 0
    } else {
      this.x = x
      this.y = y
      this.z = z
    }
  }

  equals (other, eps) {
    if (eps === undefined) {
      eps = 0
    }
    return ((Math.abs(this.x - other.x) <= eps) &&
            (Math.abs(this.y - other.y) <= eps) &&
            (Math.abs(this.z - other.z) <= eps))
  }

  length () {
    return Math.sqrt(this.dot(this))
  }

  neg () {
    return new V3(-this.x, -this.y, -this.z)
  }

  add (b) {
    return new V3(this.x + b.x, this.y + b.y, this.z + b.z)
  }

  sub (b) {
    return new V3(this.x - b.x, this.y - b.y, this.z - b.z)
  }

  multiply (w) {
    return new V3(this.x * w, this.y * w, this.z * w)
  }

  norm () {
    return this.multiply(1 / this.length())
  }

  dot (b) {
    return this.x * b.x + this.y * b.y + this.z * b.z
  }

  cross (b) {
    return new V3(
      this.y * b.z - this.z * b.y,
      this.z * b.x - this.x * b.z,
      this.x * b.y - this.y * b.x)
  }
}

export default V3