Unity 3D——射线的应用

RaycastHit raycastHit = new RaycastHit();
 Ray ray;

  ray = mainCamera.ScreenPointToRay(Input.GetTouch(0).position);

   if (Physics.Raycast(ray, out raycastHit, 6000f))
        {
            if (raycastHit.collider.GetComponent() != null)
             {
                  raycastHit.collider.GetComponent().Click();
             }
        }