unaryMinus
Overloads the unary minus operator (-).
Returns a new Vector3 instance where each component (x, y, and z) of this vector is negated. This operation does not modify the original vector.
For example, if v is Vector3(1f, -2f, 3f), then -v would result in Vector3(-1f, 2f, -3f).
Return
A new Vector3 with components (-x, -y, -z).