code: func (v Vec) Normalize() Vec {
  	l := 1.0 / v.Len()
  	return Vec{v.X * l, v.Y * l}
  }
docs: // Normalize normalizes the vector. Normalization is (1/|v|)*v,
  // making this equivalent to v.Scale(1/v.Len()). If the len is 0.0,
  // this function will return an infinite value for all elements due
  // to how floating point division works in Go (n/0.0 = math.Inf(Sign(n))).
  //
  // Normalization makes a vector's Len become 1.0 (within the margin of floating
  // point error), while maintaining its directionality.