Get last spawned object's position

Hi!
I'm using a for loop to spawn objects,and i would like to have x amount of space between the spawned objects.
But if i do it like this,it starts to make the given space bigger and bigger.

Code (CSharp):

1.  
2.  void Update()
3.     {
4.         randomSpace = Random.Range(minSpawnSpace, maxSpawnSpace);
5.     }
6.  
7. for (int i = 0; i < length; i++)
8.         {
9.             randomNumber = PickANumber(-1, 1);
10.             Vector3 pos = new Vector3(transform.position.x + randomNumber, transform.position.y, i * randomSpace);
11.             int index = Random.Range(0, objects.Length);
12.             cube = Instantiate(objects[index], pos, transform.rotation);
13.             cube.transform.parent = transform;
14.         }

I think it's because when the "i" variable starts to get bigger the gap between the objects multiplying in a wrong way.
So i think if i could get the last spawned object's position and added the random space to it's transform.position.z,it would work but i don't know how to do it.
Thanks in advance.

 

The problem seems to be here:

Code (CSharp):

1.  
2.             int index = Random.Range(0, objects.Length);
3.             cube = Instantiate(objects[index], pos, transform.rotation);
4.  

You use an object that already has an offset as a base for instantiating another object. I wouldn't be surprised if the instantiated object has the position

pos + objects[index].transform.position

.

Use a general prefab object instead. See also Prefabs (Unity Manual).

 

I tried it like this but it's still working the same way:

Code (CSharp):

1.             cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
2.             cube.transform.position = pos;

 

Hm, I see, could you post the whole code, please? It is not very clear in your initial code what is what.

I had that weird exponentially increasing offsets in the past, too, I am confident that at some point, you use a transform of an object that already has an offset. If you post the whole code, I can run some quick tests myself.

 

Yes of course,thank you for helping.

Code (CSharp):

1. using UnityEngine;
2.  
3. public class SpawnScript : MonoBehaviour
4. {
5.     private GameObject cube;
6.     public int length;
7.     public float randomSpace;
8.     float randomNumber;
9.  
10.     //-------------
11.     private float minSpawnSpace = 5f;
12.     private float maxSpawnSpace = 5f;
13.  
14.  
15.     //random rotation
16.     //spawn rate
17.  
18.     //position and rotation
19.     private Vector3 positionX;
20.     private Vector3 positionY;
21.  
22.     void Start()
23.     {
24.         Spawn();
25.     }
26.  
27.     void Update()
28.     {
29.         randomSpace = Random.Range(minSpawnSpace, maxSpawnSpace);
30.     }
31.  
32.     void SpawnX()
33.     {
34.  
35.         for (int i = 0; i < length; i++)
36.         {
37.             randomNumber = PickANumber(-1, 1);
38.             Vector3 pos = new Vector3(transform.position.x + randomNumber, transform.position.y, i * randomSpace);
39.             cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
40.             cube.transform.position = pos;
41.             cube.transform.parent = transform;
42.         }
43.     }
44.  
45.     void SpawnY()
46.     {
47.         for (int i = 0; i < length; i++)
48.         {
49.             randomNumber = PickANumber(-1, 1);
50.             Vector3 pos = new Vector3(transform.position.x, transform.position.y + randomNumber, i * randomSpace);
51.             cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
52.             cube.transform.position = pos;
53.             cube.transform.parent = transform;
54.         }
55.     }
56.  
57.     void Spawn()
58.     {
59.         SpawnX();
60.         SpawnY();
61.     }
62.  
63.     int PickANumber(int first, int second)
64.     {
65.         int[] numbers = new int[] { first, second };
66.         int index = Random.Range(0, numbers.Length);
67.         int result = numbers[index];
68.         return result;
69.     }
70. }
71.  

 

Thanks, I used it and it doesn't appear to increase the space, see the attachment. How does it look for you? I used a length of 100 with a space of 5. Even with setting minSpawnSpace and maxSpawnSpace to different values, to a range, didn't change that.

What Unity version are you using?

 

This is how it acts when i try it.
Did you try it with 3d objects?

 

Except for that red thingy, it does look exactly like mine. How should it look like?

PS: draw.io is a nice website for quickly drawing a sketch or construct a shape.

 

This is what i mean.
And i don't understand why it leaves out so much space sometimes.

 

Sorry, I genuinely don't get it.

With your spawn script, you create an array of two objects, every time with one being slightly off in x and the other one being slightly off in y. Between two of these cubes and two other ones, there is a random space in z direction. This random space is at least

minSpawnSpace

and no larger than

maxSpawnSpace

.

However, when I look at the screenshot that you posted, I see exactly that. I don't understand why you see the right space to the left and right and a supposedly huge amount of space in the middle.

Do you not want cubes sharing the same x and y coordinates to be too far off from each other?

 

No the offsets on the x and y are good,but it seems to me that it's leaving larger amount of spaces on the z axis than the maxSpawnSpace.But sometimes,as i drew on the picture,the spaces are the riight amount but sometimes it's not.At least it's seems like it.

 

You could log the difference in z between an previously spawned object and a just spawned object to see if it is true.
It could look something like this:

Code (CSharp):

1. GameObject previous = null;
2. for(int i = 0; i < length; ++i){
3.  
4.     // spawn object
5.  
6.     if(previous != null){
7.         Debug.Log(cube.transform.position.z-previous.transform.position.z);
8.     }
9.     previous = cube;
10. }

To ease your eyes and mind, you could also write:

Code (CSharp):

1.         float difference = cube.transform.position.z-previous.transform.position.z;
2.         Debug.Log(difference >= minSpawnSpace && difference <= maxSpawnSpace);

 

Yes it really did send back the right values.Thank you for replying!

 

You are welcome!