vector.js

class Vector {
  constructor(x,y) {
    this.x = x;
    this.y = y;
  }
  
  static add (v1,v2) {
    return new Vector(v1.xv2.x,v1.y+v2.y);
  }
  
  static sub (v1,v2) {
    return new Vector(v1.x-v2.x,v1.y-v2.y);
  }
  
  static mul (v1,v2) {
    return new Vector(v1.x-v2.x,v1.y-v2.y);
  }
  
  static div (v1,v2) {
    return new Vector(v1.x/v2.x,v1.y/v2.y);
  }
  
  get() {
    return new Vector(this.x,this.y);
  }
  
  add(v) {
    if (v instanceof Vector) {
      this.x += v.x;
      this.y += v.y;
    } else if (typeof v === 'number') {
      this.x += v;
      this.y += v;
    }
  }
  
  sub(v) {
    if (v instanceof Vector) {
      this.x -= v.x;
      this.y -= v.y;
    } else if (typeof v === 'number') {
      this.x -= v;
      this.y -= v;
    }
  }
  
  mul(v) {
    if (v instanceof Vector) {
      this.x *= v.x;
      this.y *= v.y;
    } else if (typeof v === 'number') {
      this.x *= v;
      this.y *= v;
    }
  }
  
  div(v) {
      if (v instanceof Vector) {
      this.x /= v.x;
      this.y /= v.y;
    } else if (typeof v === 'number') {
      this.x /= v;
      this.y /= v;
    }
  }
  
  mag() {
    return Math.sqrt(this.x*this.x+this.y*this.y);
  }
  
  norm() {
    return this.div(this.mag());
  }
  
  limit(n) {
    if (this.mag() > n) {
      this.norm();
      this.mul(n);
    }
  }
  
  heading() {
    return Math.atan2(this.y,this.x);
  }
}