Pick Up Object disapppears

Question

I'm trying to work with picking up and throwing objects. So far I've come up with a solution which does pick up the object but the same time disappears the object also. Please check to the functionality I've used.

public class pickupobject : MonoBehaviour {
     //GameObject mainCamera;
     bool carrying;
     GameObject carriedObject;
     Camera cam;
     public float distances;
     public float smooth;

     // Use this for initialization
     void Start()
     {
         cam = GameObject.Find("MainCamera").GetComponent<Camera>();
     }

     // Update is called once per frame
     void Update () {
         if(carrying)
         {
             carry(carriedObject);
         }
         else
         {
             pickup();
         }

     }

     private void pickup()
     {
         if(Input.GetKeyDown(KeyCode.E))
         {
             int x = Screen.width / 2;
             int y = Screen.height / 2;
             Ray ray = cam.ScreenPointToRay(new Vector3(x, y));
             RaycastHit hit;
             if(Physics.Raycast(ray, out hit))
             {
                 pickupable p = hit.collider.GetComponent<pickupable>();
                 if(p!=null)
                 {
                     carrying = true;
                     carriedObject = p.gameObject;
                 }
             }
         }
     }

     void carry(GameObject o)
     {
         o.GetComponent<Rigidbody>().isKinematic = true;
         o.transform.position = o.transform.position + cam.transform.position + cam.transform.forward * distances;
     }
 }

Answer 1

The problem here is, you're calling the function Carry in Update method, which means the position of your pickup object will keep increasing per frame by a factor of cam.transform.position + cam.transform.forward * distances , which will instantaneously shoot it off-screen.

If you just want to hold it, use the Carry function like this :

void carry(GameObject o)
     {
         o.GetComponent<Rigidbody>().isKinematic = true;
         o.transform.position = cam.transform.position + offset;
     }