Having issues with a NullReferenceException error. Code does as expected in some instances but I receive the error in others. Debugger directs me to line where if(hit.collider.tag == (DestructibleCube")).
using UnityEngine;
using System.Collections;
using UnityEngine.EventSystems;
public class TimeDestroy : MonoBehaviour {
public GameObject bombToDestroy;
public GameObject explosion;
public GameObject CubeExplosion;
public int PowerUpLevel;
private float timeLeft = 4;
// Use this for initialization
// This is a 4 second time to have bombs blow up.
void FixedUpdate ()
{
//sets time on instantiated object(dropped bomb) which explodes after 4 seconds
timeLeft -= Time.deltaTime;
if ( timeLeft < 0)
{
CastFwd();
CastBack();
CastLeft();
CastRight();
Instantiate(explosion, transform.position, transform.rotation); // graphic for explosion
Destroy(bombToDestroy, 0f); //removes instantiated bomb
Bomb_Pickup.bombcount += 1;
}
}
void CastFwd() // Casts a ray in the forward direction to interact with cubes
{
RaycastHit hit;
Ray landingRay = new Ray(transform.position, Vector3.forward);
Debug.DrawRay(transform.position, Vector3.forward);
Debug.Log("1");
if (Physics.Raycast(landingRay, out hit, (.3f + (PowerUpLevel * .2f))));
{
Debug.Log("2");
if (hit.collider.tag == ("DestructibleCube")) //checks for if raycast hits collider with tag
{
Debug.Log("3");
Instantiate(CubeExplosion, hit.collider.gameObject.transform.position, Quaternion.identity); //replaces gameobject with a fragmented gameobject to explose
hit.collider.gameObject.SetActive(false); //deactivates original gameobject
}
}
}
Answer by btmedia14 · Aug 18, 2016 at 03:21 AM
On the line where the Raycast is cast, there is a semi-colon at the end. This is terminating the if statement. This means that sometimes the value of hit is defined in others it is not. But in both instances the subsequent statement checking hit.collider.tag will always execute since the previous if condition has been bypassed. Line 44 notice semi-colon:
if (Physics.Raycast(landingRay, out hit, (.3f + (PowerUpLevel * .2f))));
Thanks so much! I don't think I would have ever found that. I'm surprised though that this didn't raise an issue with the debugger.
@soccer1mt Stepping through the debugger most likely what happens is the if (Physics.Raycast... executes and returns either a true or false bool value. In either case the if statement completes at the semi-colon. In the debugger the next statement executed is the hit.collider.tag check. It would give the visual impression in the debugger that the Physics.Raycast returned a true value and was stepping into its if block when actually it had already completed.
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