private void GroundMove()
{
        gravity = -9f;

        GetDirectionFromWASD();

        movement = new Vector3(this.deltaX, 0, this.deltaZ) * currentSpeed;
        movement = Vector3.ClampMagnitude(movement, currentSpeed);
        movement.y = gravity;
        movement *= Time.deltaTime;
        movement = transform.TransformDirection(movement);

        characterController.Move(movement);
 }