Using raycast, find another object, send message.

[thisizmonster]

Hello, I’m trying do Bomberman game. My current problem is can’t send detonate message from one bomb to another bomb.

1. player place bomb, which have some detonate range.
2. player place other bomb, in range of first bomb’s detonate range.
3. first bomb will detonate after 3 seconds.
4. first bomb’s fire will hit second bomb and detonate it before it’s detonate time (3 sec).

I’m using Raycast for it. Current my bomb script:

using UnityEngine;
using System.Collections;

public class bomb : MonoBehaviour {
	
	float detonateTime = 3f; 
	public GameObject explosionBomb; 
	public GameObject bombRay; 
	private int detonateLength = 2; 
	private RaycastHit hit; 

	void Start () {
		
		StartCoroutine (destroyBomb());
	}
	
	IEnumerator destroyBomb() {

		// code for detonate it after 3 sec
		yield return new WaitForSeconds(detonateTime);
		Destroy (this.gameObject);
		Instantiate (explosionBomb, transform.position, Quaternion.identity);

		// checking left direction for 3 range
		// if there are no collider, which means it's empty air, make explosion
		for (int i = 1; i <= detonateLength; i++) {

			if (!Physics.Raycast(transform.position, Vector3.left, out hit, i)) {

				Vector3 posBombRay = new Vector3(Mathf.Round(transform.position.x - i), transform.position.y, Mathf.Round (transform.position.z));
				Instantiate(bombRay, posBombRay, Quaternion.identity);
			} else if (hit.collider.tag == "Bomb") {  

				// if there are bomb left to him send detonate message to him
				hit.collider.gameObject.SendMessage("DetonateNow");
			}
		}
	}

	void detonateNow() {

		Debug.Log ("detonate now");
	}
}

---

But error is:

SendMessage DetonateNow has no receiver!
UnityEngine.GameObject:SendMessage(String, Object)
<destroyBomb>c__Iterator0:MoveNext() (at Assets/Scripts/bomb.cs:43)

[iwaldrop]

I bet it’s because you’re looping back and forth between two bombs.

When one bomb tells another to explode then the second will tell the first, which will tell the second, and on and on forever. You’ll never leave the frame. You might even get a stack overflow.

You should have an isExploded flag, set it, and check it before doing anything.

private bool isExploded;

void DetonateNow()
{
    if (isExploded)
        return;
    isExploded = true;
    
    // the rest of the method as you have it.
}