[Unity][찾기] 카메라에 마우스가 있는지 유무 판단.

  Vector3 viewMouse = Cam.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, -Cam.transform.position.z));
  Vector3 viewPos = Cam.WorldToViewportPoint(viewMouse);

                if (viewPos != null && viewPos.x >= 0 && viewPos.x <= 1 && viewPos.y >= 0 && viewPos.y <= 1 && viewPos.z > 0)
                {
                  
                }
                else
                {
                    return null;
                }