static subtract(vecA, vecB) {
    return new Vector2(vecA.x - vecB.x, vecA.y - vecB.y);
  }
Subtracts one vector from another and returns the result as a new vector.

@static
@param {Vector2} vecA The minuend.
@param {Vector2} vecB The subtrahend.
@returns {Vector2} Returns the difference of two vectors.