Randomizing Objects Positions When Scene is Loaded (memorygame)

Hi!

I'm really just couple of weeks into C# and Unity so don't laugh if I don't understand.
I tried to go through all threads with similar questions but it didn't really work for me.

So I'm making a 3D memory game where 3rd Person can walk on objects and the objects play a sound. The player is supposed to find 8 pairs of the same sound to win. The 16 objects are in 4 by 4 formation on the scene.

The problem is that I would like the 16 object to be randomly placed in the same 4 by 4 formation when the scene is loaded.

I've made a public Vector3[] ObjectPositions, of all the 16 possible positions
I've also tried making public GameObject[] Plates of all the 16 objects but I really don't know how to proceed with this.

Code (CSharp):

1.  
2. public class positions : MonoBehaviour
3. {
4.     public Vector3[] Objectpositions;
5.     public GameObject[] Plates;
6.     private void Start()
7.     {
8.        
9.            
10.        
11.     }
12. }
13.     }

 

I think the easiest way to do this is by mix up the indexes:

Code (CSharp):

1.  
2. int[] rndIdx { get; set; }
3.  
4. void Start()
5. {
6.     var size = Plates.Length;
7.     rndIdx = new int[size];
8.     for (int i = 0; i < size; i++)
9.     {
10.         rndIdx[i] = i;
11.     }
12.     RandomIndexes(size, 2);//here is mixing up indexes 2 times
13. }
14.  
15.  
16. void RandomIndexes(int size, int mixesUp)
17. {
18.     Random rnd = new Random();// this is from .NET
19.     //var rnd = Random.Range(0,size); <- you can use this
20.     for (int mix = 0; mix < mixesUp; mix++)
21.     {
22.         for (int i = 0; i < size; i++)
23.         {
24.             var x = rnd.Next(0, size);
25.             var t = rndIdx[i];
26.             rndIdx[i] = rndIdx[x];
27.             rndIdx[x] = t;
28.         }
29.     }
30. }
31.  

Later on you need to use

Code (csharp):

1.  
2. Objectpositions[rndIdx[ yourIndex ]];
3.  
4. //like
5. for (int i = 0; i < n; i++)
6. {
7.   Vector3 pos = Objectpositions[rndIdx[i]];
8.   //pos is a random position from your Objectpositions
9.   GameObject plate = Plates[i];//you took the plate
10.   plate.tranform.position = pos;// and place it at your random position
11. }
12.  

 

A similar idea to the above that might be a bit easier to understand, C# has built-in types that make some of this easier. In particular, List<T> is a collection that's similar to an array, but it has some nicer properties like being able to add elements to it whenever you want. So I would modify your code slightly to use those:

Code (csharp):

1. using System.Collections.Generic;
2.  
3. public class positions : MonoBehaviour
4. {
5.    public List<Vector3> objectPositions; // The <> brackets here specify what type of List this is, or what each element's type is. So, this is a list of vectors.
6.    public List<GameObject> plates; // This is a list of GameObjects. I'm guessing these aren't prefabs, so they are objects that already exist in the scene. If you dragged them in from the Project panel, they are prefabs; if you dragged them from the scene view or hierarchy, they are scene objects.
7.  
8.    public void Start()
9.    {
10.       // First, we'll make a temporary list that holds all of the plates. This won't change the list that already exists.
11.       List<GameObject> remainingObjects = new List<GameObject>(plates);
12.  
13.       // for loops are one of the most important control structures for programmers. If you haven't seen them before, check out the learn section. Loops are one of the main super-powers of a computer.
14.       // Loop through each object position, pick a random object, and put that object in the given position
15.       for(int i = 0; i < objectPositions.Count; i++)
16.       {
17.           // Pick a random remaining object
18.           int index = Random.Range(0, remainingObjects.Count);
19.           GameObject randomObject = remainingObjects[index];
20.  
21.           // Remove the object we chose from the pool of remaining objects
22.           remainingObjects.RemoveAt(index);
23.          
24.           // Move the object to the position we are currently trying to fill
25.           randomObject.transform.postion = objectPositions[i];
26.       }
27.    }
28. }

 

Hey!
Thanks so much for the answers, you're amazing!

I got it working even though to be honest I don't absolutely understand everything that's going on.
But I'm now definitely inspired to go learn c# more so I will understand it in the future.