My enemies won't die when I hit them with harpoons

Unity Engine
1

Hey all,

I posted about this previously but have not been able to get something in my game to work. I am making an underwater FPS style game where the player can shoot harpoon objects. I want the enemies to take damage when the harpoon collides with them. Unfortunately, I cannot seem to get the harpoondamage script to talk to the damagetaker script that I am using. I am very very new to scripting (having primarily worked as an artist) but on this project I’m pretty much the only one crazy enough to take on the task. Here are both of them:

HarpoonDamage:

var harpoonDamage = 10.0;
var hitEffect : GameObject;
private var hit : Collision;

function OnCollisionEnter() {

		
		//Send a damage message to the hit object
		if (hit.collider.tag == "Enemy" || hit.collider.tag == "Projectile")
		{
			/*Instantiate(hitEffect, hit.point, Quaternion.identity);*/
			hit.collider.SendMessage("ApplyDamage", harpoonDamage, SendMessageOptions.DontRequireReceiver);

}
}

DamageReceiver:

var hitPoints = 100.0;
var detonationDelay = 0.0;
var explosion : Transform;
var deadReplacement : Rigidbody;

function ApplyDamage(damage : float){
	
	//We already have less than 0 hitpoints, maybe we got killed already?
	if(hitPoints <= 0.0)
	return;
	
	hitPoints -= damage;
	if(hitPoints <= 0.0){
		//Start emitting particles
		var emitter : ParticleEmitter = GetComponentInChildren(ParticleEmitter);
		if(emitter)
		emitter.emit = true; 
		
		Invoke("DelayedDetonate", detonationDelay);
	}
}

function DelayedDetonate(){
	BroadcastMessage("Detonate");
}

function Detonate(){
	
	//Destroy ourselves
	Destroy(gameObject);
	
	//Create the explosion
	if(explosion)
	Instantiate(explosion, transform.position, transform.rotation);
	
	//If we have a dead barrel then replace ourselves with it!
	if(deadReplacement){
		var dead : Rigidbody = Instantiate(deadReplacement, transform.position, transform.rotation);
		
		//For better effect we assign the same velocity to the exploded barrel
		dead.rigidbody.velocity = rigidbody.velocity;
		dead.angularVelocity = rigidbody.angularVelocity;
	}
	
	//If there is a particle emitter stop emitting and detach it so it doesnt get destroyed right away
	
	var emitter : ParticleEmitter = GetComponentInChildren(ParticleEmitter);
	
	if(emitter){
		emitter.emit = false;
		emitter.transform.parent = null;
	}
}

//We require the barrel to be a rigidbody, so that it can do nice physics

@script RequireComponent(Rigidbody)

I always seem to get this error message: NullReferenceException: Object reference not set to an instance of an object
HarpoonDamage.OnCollisionEnter () (at Assets/Scripts/HarpoonDamage.js:9)

Whenever my harpoons hit anything. Can someone please help?

BTW…I have done both the FPS and platformer tutorials. Some of the scripts are derived from them but I still cannot get them to work.

2

For your information, “hit” is usually the name of the variable used to retrieve the collisions informations for a character controller.

When a character controller collide with a collider, OnCharacterControllerHit function is triggered. The data of that event (ControllerColliderHit) is usually sent in a variable called “hit”, as in the example (you could change its name as you want, dataCollision : ControllerColliderHit, for example).

In your Harpoon script, you are using hit (hit.collider.tag). It is up to you to choose the word (it is just a name). But you must specify the name of the data.

Usually, OnCollisionEnter 's data is called collisionInfo, its type is Collision. If you are going for the word hit, so be it.

function OnCollisionEnter (hit : Collision)

3

HOLY COW THAT DID IT!

Thank you so much the viper fish in my game die now! Now to move on to making my player character die…