A way to randomly spawn at random times SOLVED

Unity Engine
1

Ok, so I’ve been trying to learn this stuff all day but nothing seems to work well. I have over 20 test scripts with the beginning title of RandomSpawn. :frowning:

I have about 10 objects. I want them to spawn in a random order. And they need to spawn at random times. BUT, it can’t be random enough that it can spawn in a matter of milliseconds and collide with a previous spawn.

This is what I’ve got so far.

var Car001 : GameObject;
var Car002 : GameObject;

var CarDecider = 0;
var WaitTime = 0;

var StartSpawn = false;

function Update () {
	if (StartSpawn == false) {
		CarDecider = 1 + (Random.value);
		WaitTime = 1 + (Random.value);
		StartSpawn = true;
	}
	if ( CarDecider > 1.5) {
		Invoke ("SpawnCar001", WaitTime);
		CarDecider = 0;
	}
	if ( CarDecider < 1.5) {
		Invoke ("SpawnCar002", WaitTime);
		CarDecider = 0;
	}
}

function SpawnCar001 () {
	clone = Instantiate(Car001, transform.position, transform.rotation);
}

function SpawnCar002 () {
	clone = Instantiate(Car002, transform.position, transform.rotation);
}

All it does is spawn Car002 infinity. Any idea how to fix this?

2

Hi,

I i rewrote your script the way i would but haven’t tested it, though it should work if there aren’t any typos lol.

//Minimum time to wait before spawning a random object (in seconds)
var min_wait_time = 0.5;

//max time to wait before spawning a random object (in seconds)
var max_wait_time = 10.0;

//We will use a array of game objects and assign them in the editor
var obj : GameObject[];

var start_spawn = false;

function spawn_random_object(id,wait_time)
{
	//Wait for wait_time
	yield WaitForSeconds(wait_time);
	//Spawn obj
	clone = Instantiate(obj[id], transform.position, transform.rotation); 
}

function Update()
{
	if(start_spawn == true)
	{	
		/*
		Call the spawn function with the id set to a random number between 0 and the length of the obj array -1 (since arrays start at 0)
		Then set the wait_time to a random float number between the min_wait_time and max_wait_time (Note: We add0.1 because the max in random.range
		is exclusive and in order to get the max value as a result the max must be greater.
		*/
		Spawn_Random_Object(Random.Range(0,obj.length)-1,Random.Range(min_wait_time,max_wait_time + 0.1))
	}
}
3

Update runs every frame; you should stay away from it unless you have code that you literally want to run every single frame, which is definitely not the case here. Also:

var CarDecider = 0; 
var WaitTime = 0;

This makes these variables into integers, so

CarDecider = 1 + (Random.value);

will always result in 1. Either specify floats explicitly or use 0.0 instead of 0.

Also, whenever you have more than one object of a similar type, use an array, not a collection of single variables.

var cars : GameObject[];
var minWaitTime = 1.0;
var maxWaitTime = 5.0;

function Start () {
	while (true) {
		yield WaitForSeconds (Random.Range(minWaitTime, maxWaitTime));
		Instantiate (cars[Random.Range(0, cars.Length)], transform.position, transform.rotation);
	}
}

–Eric

4

ok! its all sorted out! Thank you guys sooo much. INTERNET HUUUG!!!