Realtime distance check with enemies

Scripting
1

Hi,

I have a script (from the Unity docs) that checks the nearest enemy. The script works fine but it only checks every object (enemy) ones. When the player moves close to a previous object the script does not detect (update) it.

Script:

print(FindClosestEnemy().name);
// Find the name of the closest enemy
function FindClosestEnemy () : GameObject {
// Find all game objects with tag Enemy
var gos : GameObject[];
gos = GameObject.FindGameObjectsWithTag("Enemy");
var closest : GameObject;
var distance = Mathf.Infinity;
var position = transform.position;
// Iterate through them and find the closest one
for (var go : GameObject in gos) {
var diff = (go.transform.position - position);
var curDistance = diff.sqrMagnitude;
if (curDistance < distance) {
closest = go;
distance = curDistance;
}
}
return closest;
}

I think it has to do with the for loop that is not being reset. Can someone please help me with this?

Thanks!

2

Any code not in an event handler will be executed ONCE when the object is first activated, so there’s your problem.

If you put:

print(FindClosestEnemy().name);

inside:

function FixedUpdate(){
…
}

it would spam it constantly.

You could also put it in a coroutine that only wakes up periodically (e.g. every 0.5 seconds)

e.g.

function CheckForEnemies(){
  while( true ){
    print(FindClosestEnemy().name);
    yield new WaitForSeconds( 0.5 );
  }
}

Now, call this function once and it will keep checking for the nearest enemy periodically.

3

Thanks! What a fast reply! Both methods are working fine.

4

Hi,

This looks promising, I’m trying to make an auto-aim script for the player and it needs to look at the closest targets.

I’ll put it in a button function. Hope it will work. Probably going to post if it works, or if it doesn’t.

5

Hi I having a same issue Frido. but I tried the way that is being mentioned. like putting inside a fixedupdate but still nothing happened it still detect my first object only. Even i move near to the other object it still does not update to the other object that i am near it.

So frido can i ask how you solve the issue. Thanks.

6

Yeah, could you please post your script so we could see what you came up with ? I need this too :smile:

And I think it could be useful for more people too :slight_smile:

7

Okay, I got an error message for the part that says:

function FindClosestEnemy () : GameObject {

Seems like unity dislikes the “: GameObject”… :?

8

someone know how he did it, or how to make it work ?

9

I used this code, and it works perfectly. Of course, you have to actually do something with the GameObject that gets returned from calling this function, but here it is:

// Find the closest enemy 
function FindClosestEnemy () : GameObject { 
	// Find all game objects with tag Enemy 
	var gos : GameObject[]; 
	gos = GameObject.FindGameObjectsWithTag("Enemies"); 
	var closest : GameObject; 
	var distance = Mathf.Infinity; 
	var position = transform.position; 
	// Iterate through them and find the closest one 
	for (var go : GameObject in gos) { 
		var diff = (go.transform.position - position); 
		var curDistance = diff.sqrMagnitude; 
		if (curDistance < distance) { 
			closest = go; 
			distance = curDistance; 
		} 
	} 
	return closest; 
}
10

So for example, you could have something similar to this in Update:

function Update() {
	if (Input.GetMouseButton(1)) 
	{
			isEnemyTargeted = true;
			targetedEnemy = FindClosestEnemy();
			DeselectOtherEnemies();
			var script : MouseInteractionObject = targetedEnemy.GetComponent(MouseInteractionObject);
			script.isSelected = true;
   }		
}

This makes it so if you click the Right Mouse button it targets the closest enemy. It then sets isSelected to true on a script called MouseInteractionObject that is attached to all Enemies. You can then do something to the enemy if isSelected = true. I also have a function here called DeselectOtherEnemies() that goes through and deselects all of them before selecting the single correct one.

11

Ok thanks :smile: I don’t have the time to try this right now but does this code updates everytime ?

like if I move are the closest enemy updated ?