How to reference a multidimensional list?

Questions & Answers
1

I have been following a tutorial on creating a minecraft like world, but want to change an array to a list to allow for infinite generation.

I want to be able to pass a “chunks[x, y, z].Init” or something to that effect from the world but I’m struggling. using the array it works but when changing to either of the two lists I just cant get it to work. I have the following;

using System.Linq;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class World : MonoBehaviour
{
    /*List<Chunk[,,]> chunks = new List<Chunk[,,]>();*/
    List<Chunk> chunks = new List<Chunk>();
    /*Chunk[,,] chunks = new Chunk[20, 20, 20];*/
    List<ChunkCoord> chunksToCreate = new List<ChunkCoord>();
    private bool isCreatingChunks;
    private void Start()
    {
        GenerateWorld();   
    }
    private void Update()
    {
        CreateChunks();
    }
    void GenerateWorld()
    {
        for (int x = 0; x < 2; x++)
        {
            for (int y = 0; y < 2; y++)
            {
                for (int z = 0; z < 2; z++)
                {
                    chunks.Add(new Chunk(new ChunkCoord(x, y, z), this, false));
                    chunksToCreate.Add(new ChunkCoord(x, y, z));
                }
            }
        }
    }
    IEnumerator CreateChunks()
    {
        isCreatingChunks = true;
        while (chunksToCreate.Count > 0)
        {
            chunks.Init();
            chunksToCreate.RemoveAt(0);
            yield return null;
        }
        isCreatingChunks = false;
    }
}

and

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Chunk
{
	public ChunkCoord coord;
	World world;
	GameObject chunkObject;
	public Chunk(ChunkCoord _coord, World _world, bool generateOnLoad)
	{
		coord = _coord;
		world = _world;
		if (generateOnLoad)
			Init();
	}
	public void Init()
	{
		chunkObject = new GameObject();
		chunkObject.transform.SetParent(world.transform);
		chunkObject.transform.position = new Vector3(coord.x * Settings.ChunkSize, coord.y * Settings.ChunkSize, coord.z * Settings.ChunkSize);
		chunkObject.name = coord.x + ", " + coord.y + ", " + coord.z;
		Debug.Log("Chunk: " + coord.x + ", " + coord.y + ", " + coord.z + " generated.");
	}
}
public class ChunkCoord
{
	public int x;
	public int y;
	public int z;
	public ChunkCoord()
	{
		x = 0;
		y = 0;
		z = 0;
	}
	public ChunkCoord(int _x, int _y, int _z)
	{
		x = _x;
		y = _y;
		z = _z;
	}
	public bool Equals(ChunkCoord other)
	{
		if (other == null)
			return false;
		else if (other.x == x && other.y == y && other.z == z)
			return true;
		else
			return false;
	}
}
2

I’d suggest using a nested List. It can be a little difficult to parse, but basically you want a List of Lists of Lists of Chunks. This will effectively give you a three dimensional List of Chunks and, if initialized correctly, it can be accessed using indices that line up with your Chunk’s coord field.
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The declaration would look like this:

List<List<List<Chunk>>> chunks = new List<List<List<Chunk>>>();

&nbsp
And an individual element at coords (x, y, z) would be accessed like this:

chunks[x][y][z].Init();

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I’ve made a couple of changes to your World class to get rid of the redundant secondary list (just use nested foreach loops for initialization) and correctly implement the CreateChunks() coroutine; hopefully this should be more or less what you’re looking for:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class World : MonoBehaviour
{
    private List<List<List<Chunk>>> chunks = new List<List<List<Chunk>>>();

    private bool isCreatingChunks = false;

    private void Start()
    {
        GenerateWorld();
    }

    private void Update()
    {
        if (!isCreatingChunks)
        {
            StartCoroutine(CreateChunks());
        }
    }

    void GenerateWorld()
    {
        for (int x = 0; x < 2; x++)
        {
            chunks.Add(new List<List<Chunk>>());

            for (int y = 0; y < 2; y++)
            {
                chunks[x].Add(new List<Chunk>());

                for (int z = 0; z < 2; z++)
                {
                    chunks[x][y].Add(new Chunk(new ChunkCoord(x, y, z), this, false));
                }
            }
        }
    }

    private IEnumerator CreateChunks()
    {
        isCreatingChunks = true;
        
        foreach (List<List<Chunk>> xChunks in chunks)
        {
            foreach (List<Chunk> yChunks in xChunks)
            {
                foreach(Chunk chunk in yChunks)
                {
                    chunk.Init();

                    yield return null;
                }
            }
        }
    }
}